THE STATE OF CLIMATE CHANGE SCIENCE 2007

HEARINGS

BEFORE THE

COMMITTEE ON SCIENCE AND

TECHNOLOGY

ONE HUNDRED TENTH CONGRESS

FIRST SESSION

February 8, April 17, and May 15, 2007

Serial Nos. 110–2, 110–20, and 110–30

Printed for the use of the Committee on Science and Technology

(

THE STATE OF CLIMATE CHANGE SCIENCE 2007

U.S. GOVERNMENT PRINTING OFFICE

WASHINGTON : 

For sale by the Superintendent of Documents, U.S. Government Printing Office

Internet: bookstore.gpo.gov Phone: toll free (866) 512–1800; DC area (202) 512–1800

Fax: (202) 512–2104 Mail: Stop IDCC, Washington, DC 20402–0001

32–966PS 2007

THE STATE OF CLIMATE CHANGE SCIENCE 2007

HEARINGS

BEFORE THE

COMMITTEE ON SCIENCE AND

TECHNOLOGY

ONE HUNDRED TENTH CONGRESS

FIRST SESSION

February 8, April 17, and May 15, 2007

Serial Nos. 110–2, 110–20, and 110–30

Printed for the use of the Committee on Science and Technology

(

Available via the World Wide Web: http://www.science.house.gov

(II)

COMMITTEE ON SCIENCE AND TECHNOLOGY

HON. BART GORDON, Tennessee, Chairman

JERRY F. COSTELLO, Illinois

EDDIE BERNICE JOHNSON, Texas

LYNN C. WOOLSEY, California

MARK UDALL, Colorado

DAVID WU, Oregon

BRIAN BAIRD, Washington

BRAD MILLER, North Carolina

DANIEL LIPINSKI, Illinois

NICK LAMPSON, Texas

GABRIELLE GIFFORDS, Arizona

JERRY MCNERNEY, California

PAUL KANJORSKI, Pennsylvania

DARLENE HOOLEY, Oregon

STEVEN R. ROTHMAN, New Jersey

MICHAEL M. HONDA, California

JIM MATHESON, Utah

MIKE ROSS, Arkansas

BEN CHANDLER, Kentucky

RUSS CARNAHAN, Missouri

CHARLIE MELANCON, Louisiana

BARON P. HILL, Indiana

HARRY E. MITCHELL, Arizona

CHARLES A. WILSON, Ohio

RALPH M. HALL, Texas

F. JAMES SENSENBRENNER JR.,

Wisconsin

LAMAR S. SMITH, Texas

DANA ROHRABACHER, California

KEN CALVERT, California

ROSCOE G. BARTLETT, Maryland

VERNON J. EHLERS, Michigan

FRANK D. LUCAS, Oklahoma

JUDY BIGGERT, Illinois

W. TODD AKIN, Missouri

JO BONNER, Alabama

TOM FEENEY, Florida

RANDY NEUGEBAUER, Texas

BOB INGLIS, South Carolina

MICHAEL T. MCCAUL, Texas

MARIO DIAZ-BALART, Florida

PHIL GINGREY, Georgia

BRIAN P. BILBRAY, California

ADRIAN SMITH, Nebraska

VACANCY

(III)

The State of Climate Change Science 2007: The Findings

of the Fourth Assessment Report by the Intergovernmental Panel on Climate Change (IPCC), Working

Group I Report

C O N T E N T S

February 8, 2007

Page

Witness List ............................................................................................................. 2

Hearing Charter ...................................................................................................... 3

Opening Statements

Statement by Representative Bart Gordon, Chairman, Committee on Science

and Technology, U.S. House of Representatives ............................................... 7

Written Statement ............................................................................................ 8

Statement by Representative Ralph M. Hall, Minority Ranking Member,

Committee on Science and Technology, U.S. House of Representatives ......... 9

Written Statement ............................................................................................ 11

Prepared Statement by Representative Jerry F. Costello, Member, Committee

on Science and Technology, U.S. House of Representatives ............................. 12

Prepared Statement by Representative Eddie Bernice Johnson, Member, Committee on Science and Technology, U.S. House of Representatives ................. 13

Prepared Statement by Representative Daniel Lipinski, Member, Committee

on Science and Technology, U.S. House of Representatives ............................. 13

Prepared Statement by Representative Mike Ross, Member, Committee on

Science and Technology, U.S. House of Representatives .................................. 13

Prepared Statement by Representative Russ Carnahan, Member, Committee

on Science and Technology, U.S. House of Representatives ............................. 14

Prepared Statement by Representative Harry E. Mitchell, Member, Committee on Science and Technology, U.S. House of Representatives ................. 14

Prepared Statement by Representative Vernon J. Ehlers, Member, Committee

on Science and Technology, U.S. House of Representatives ............................. 15

Prepared Statement by Representative Randy Neugebauer, Member, Committee on Science and Technology, U.S. House of Representatives ................. 15

Panel I:

The Honorable Nancy Pelosi, Speaker of the House of Representatives

Oral Statement ................................................................................................. 16

Written Statement ............................................................................................ 19

Discussion

Economic Impacts of Climate Change ................................................................ 21

Select Committee on Energy Independence and Global Warming .................. 22

Nuclear Energy .................................................................................................... 23

The International Banking Environmental Protection Act .............................. 24

Question and Answer Session: Congressional Customs .................................... 25

Page

IV

Panel II:

Dr. Susan Solomon, Co-Chair, IPCC, Working Group I: The Physical Basis

of Climate Change; Senior Scientist, Earth System Research Laboratory,

Office of Oceanic and Atmospheric Research, National Oceanic and Atmospheric Administration, U.S. Department of Commerce

Oral Statement ................................................................................................. 28

Written Statement ............................................................................................ 30

Biography .......................................................................................................... 46

Dr. Kevin E. Trenberth, Coordinating Lead Author, IPCC, Working Group

I, Chapter 3: Observations: Surface and Atmospheric Climate Change;

Head, Climate Analysis Section, National Center for Atmospheric Research

Oral Statement ................................................................................................. 46

Written Statement ............................................................................................ 49

Biography .......................................................................................................... 55

Dr. Richard B. Alley, Lead Author, IPCC, Working Group I, Chapter 4:

Observations: Changes in Snow, Ice and Frozen Ground; Evan Pugh Professor of Geosciences and Associate of the Earth and Environmental Systems Institute, Pennsylvania State University

Oral Statement ................................................................................................. 56

Written Statement ............................................................................................ 57

Biography .......................................................................................................... 61

Dr. Gerald A. Meehl, Coordinating Lead Author, IPCC, Working Group I,

Chapter 10: Global Climate Projections; Senior Scientist, National Center

for Atmospheric Research

Oral Statement ................................................................................................. 61

Written Statement ............................................................................................ 63

Biography .......................................................................................................... 66

Discussion

The IPCC Process ................................................................................................. 67

Glacier Melt Accelerations .................................................................................. 67

Global Warming Trends ...................................................................................... 70

More on the IPCC Process ................................................................................... 73

More on Global Warming Trends ....................................................................... 74

Greenhouse Gas Production: Country Comparisons ......................................... 77

Climate Research ................................................................................................. 77

Carbon Sequestration .......................................................................................... 79

Advancements in Climate Research ................................................................... 81

Cooling in Antarctica ........................................................................................... 81

Impact on the Western United States ................................................................ 81

Thermal Expansion of Seawater ......................................................................... 82

Mitigating Climate Change ................................................................................. 82

Ocean Circulation Changes ................................................................................. 83

Tropical Storms .................................................................................................... 85

Social and Economic Impacts of Climate Change ............................................. 86

More on the IPCC Process ................................................................................... 86

Global Impacts of Climate Change ..................................................................... 87

Managing Water Resources ................................................................................. 88

More on Climate Research .................................................................................. 89

Opposition to Climate Change ............................................................................ 90

Climate Change Scenarios ................................................................................... 93

More Climate Change Scenarios ......................................................................... 93

Scientific Consensus ............................................................................................ 94

Impact on the Southwestern United States ....................................................... 96

Regional vs. Global Modeling .............................................................................. 97

U.S. Leadership in Mitigating Climate Change ................................................ 98

More on Climate Science ..................................................................................... 100

Appendix: Answers to Post-Hearing Questions

Dr. Susan Solomon, Co-Chair, IPCC, Working Group I: The Physical Basis

of Climate Change; Senior Scientist, Earth System Research Laboratory,

Office of Oceanic and Atmospheric Research, National Oceanic and Atmospheric Administration, U.S. Department of Commerce .................................... 106

Page

V

Joint responses by Dr. Richard B. Alley, Lead Author, IPCC, Working Group

I, Chapter 4: Observations: Changes in Snow, Ice and Frozen Ground;

Evan Pugh Professor of Geosciences and Associate of the Earth and Environmental Systems Institute, Pennsylvania State University; Dr. Kevin E.

Trenberth, Coordinating Lead Author, IPCC, Working Group I, Chapter

3: Observations: Surface and Atmospheric Climate Change; Head, Climate

Analysis Section, National Center for Atmospheric Research; Dr. Gerald

A. Meehl, Coordinating Lead Author, IPCC, Working Group I, Chapter

10: Global Climate Projections; Senior Scientist, National Center for Atmospheric Research; and Dr. Susan Solomon, Co-Chair, IPCC, Working Group

I: The Physical Basis of Climate Change; Senior Scientist, Earth System

Research Laboratory, Office of Oceanic and Atmospheric Research, National

Oceanic and Atmospheric Administration, U.S. Department of Commerce .... 107

The State of Climate Change Science 2007: The Findings

of the Fourth Assessment Report by the Intergovernmental Panel on Climate Change (IPCC), Working

Group II: Climate Change Impacts, Adaptation and

Vulnerability

C O N T E N T S

April 17, 2007

Page

Witness List ............................................................................................................. 112

Hearing Charter ...................................................................................................... 113

Opening Statements

Statement by Representative Bart Gordon, Chairman, Committee on Science

and Technology, U.S. House of Representatives ............................................... 119

Written Statement ............................................................................................ 119

Statement by Representative Ralph M. Hall, Minority Ranking Member,

Committee on Science and Technology, U.S. House of Representatives ......... 120

Written Statement ............................................................................................ 121

Prepared Statement by Representative Jerry F. Costello, Member, Committee

on Science and Technology, U.S. House of Representatives ............................. 122

Prepared Statement by Representative Nick Lampson, Chairman, Subcommittee on Energy and Environment, Committee on Science and Technology, U.S. House of Representatives ............................................................... 122

Prepared Statement by Representative Harry E. Mitchell, Member, Committee on Science and Technology, U.S. House of Representatives ................. 123

Prepared Statement by Representative Vernon J. Ehlers, Member, Committee

on Science and Technology, U.S. House of Representatives ............................. 123

Witnesses:

Dr. Cynthia Rosenzweig, Senior Research Scientist, NASA Goddard Institute

for Space Studies, The Earth Institute at Columbia University

Oral Statement ................................................................................................. 125

Written Statement ............................................................................................ 126

Biography .......................................................................................................... 130

Dr. William E. Easterling, Professor of Geography and Agronomy; Director,

Penn State Institutes of Energy and the Environment, Pennsylvania State

University

Oral Statement ................................................................................................. 130

Written Statement ............................................................................................ 134

Biography .......................................................................................................... 137

Dr. Virginia Burkett, Chief Scientist for Global Change Research, U.S. Geological Survey, U.S. Department of the Interior

Oral Statement ................................................................................................. 138

Page

VI

Dr. Virginia Burkett, Chief Scientist for Global Change Research, U.S. Geological Survey, U.S. Department of the Interior—Continued

Written Statement ............................................................................................ 143

Dr. Shardul Agrawala, Princeton University and Organisation for Economic

Co-operation and Development (OECD)

Oral Statement ................................................................................................. 154

Written Statement ............................................................................................ 156

Biography .......................................................................................................... 158

Dr. Roger S. Pulwarty, Program Director, National Integrated Drought Information System (NIDIS), Office of Oceanic and Atmospheric Research, National Oceanic and Atmospheric Administration, U.S. Department of Commerce

Oral Statement ................................................................................................. 158

Written Statement ............................................................................................ 160

Biography .......................................................................................................... 164

Dr. Stephen H. Schneider, Melvin and Joan Lane Professor for Interdisciplinary Environmental Studies; Professor, Department of Biological Sciences;

Senior Fellow, Center for Environmental Science and Policy at the Woods

Institute for the Environment, Stanford University

Oral Statement ................................................................................................. 165

Written Statement ............................................................................................ 170

Biography .......................................................................................................... 179

Discussion

Dangerous Anthropogenic Interference .............................................................. 180

Potential Mitigation of Climate Change ............................................................ 181

Climate Change Impacts ..................................................................................... 181

Anthropogenic Causes of Climate Change ......................................................... 181

Climate Change Impacts: Drought ..................................................................... 182

Climate Change Impacts: The Great Lakes ....................................................... 183

Carbon Sinks ........................................................................................................ 184

Impacts on the Fishing Industry ........................................................................ 184

Energy Concerns .................................................................................................. 186

International Efforts ............................................................................................ 187

Adaptation and Mitigation Strategies ................................................................ 189

Climate Change Impacts: Agriculture ................................................................ 191

Climate Change Impacts: Water Availability .................................................... 191

Climate Change Impacts: Coastal Louisiana ..................................................... 194

Air Indexing in Third World Countries .............................................................. 196

Global Dimming ................................................................................................... 197

Climate Change Impacts: Southern Arizona ..................................................... 198

Sunspots ................................................................................................................ 199

Sea Walls .............................................................................................................. 201

The IPCC Process ................................................................................................. 201

Appendix 1: Answers to Post-Hearing Questions

Dr. Cynthia Rosenzweig, Senior Research Scientist, NASA Goddard Institute

for Space Studies, The Earth Institute at Columbia University ...................... 206

Dr. Virginia Burkett, Chief Scientist for Global Change Research, U.S. Geological Survey, U.S. Department of the Interior ................................................ 208

Dr. Roger S. Pulwarty, Physical Scientist, Climate Program Office, Office

of Oceanic and Atmospheric Research, National Oceanic and Atmospheric

Administration, U.S. Department of Commerce ................................................ 212

Dr. Stephen H. Schneider, Melvin and Joan Lane Professor for Interdisciplinary Environmental Studies; Professor, Department of Biological Sciences;

Senior Fellow, Center for Environmental Science and Policy at the Woods

Institute for the Environment, Stanford University ......................................... 217

Appendix 2: Additional Material for the Record

More Trees, Less Global Warming, Right?—Not Exactly, Scientific American,

April 10, 2007 ....................................................................................................... 222

Why So Gloomy?, by Richard S. Lindzen, Special to Newsweek, April 16,

2007 ....................................................................................................................... 224

Page

VII

The State of Climate Change Science 2007: The Findings

of the Fourth Assessment Report by the Intergovernmental Panel on Climate Change (IPCC), Working

Group III: Mitigation of Climate Change

C O N T E N T S

May 16, 2007

Page

Witness List ............................................................................................................. 228

Hearing Charter ...................................................................................................... 229

Opening Statements

Statement by Representative Bart Gordon, Chairman, Committee on Science

and Technology, U.S. House of Representatives ............................................... 237

Written Statement ............................................................................................ 238

Statement by Representative Ralph M. Hall, Ranking Minority Member,

Committee on Science and Technology, U.S. House of Representatives ......... 238

Written Statement ............................................................................................ 240

Prepared Statement by Representative Jerry F. Costello, Member, Committee

on Science and Technology, U.S. House of Representatives ............................. 241

Prepared Statement by Representative Eddie Bernice Johnson, Member, Committee on Science and Technology, U.S. House of Representatives ................. 241

Witnesses:

Dr. Mark D. Levine, Division Director of the Environmental Energy Technology Division at Lawrence Berkeley Laboratory

Oral Statement ................................................................................................. 242

Written Statement ............................................................................................ 244

Biography .......................................................................................................... 247

Dr. William A. Pizer, Fellow at Resources for the Future and Senior Economist at the National Commission on Energy Policy

Oral Statement ................................................................................................. 247

Written Statement ............................................................................................ 250

Biography .......................................................................................................... 259

Mr. Steven E. Plotkin, Transportation Energy Analyst with the Center of

Transportation Research at the Argonne National Laboratory

Oral Statement ................................................................................................. 260

Written Statement ............................................................................................ 262

Biography .......................................................................................................... 265

Dr. Roger A. Pielke, Jr., Professor of Environmental Studies Program at

the University of Colorado and Director of the Center for Science and

Technological Policy Research

Oral Statement ................................................................................................. 265

Written Statement ............................................................................................ 270

Biography .......................................................................................................... 280

Discussion

Biofuels ................................................................................................................. 280

Fuel Economy Standards in China ..................................................................... 280

International Efforts ............................................................................................ 281

The Advanced Research Projects Agency–Energy (ARPA–E) .......................... 282

Adaptation and Mitigation Strategies ................................................................ 282

The IPCC Process ................................................................................................. 283

Adaptation and Mitigation Strategies in China ................................................ 284

Green Employment Opportunities ...................................................................... 285

Building Efficiency ............................................................................................... 285

More on International Efforts ............................................................................. 286

Efficiency Technologies ........................................................................................ 288

More on Building Efficiency ................................................................................ 289

Page

VIII

Anthropogenic Causes of Climate Change ......................................................... 290

Mitigation Obstacles ............................................................................................ 292

Mitigation Costs ................................................................................................... 293

Developing Countries ........................................................................................... 294

More on Building Efficiency ................................................................................ 294

China’s Coal Energy Production ......................................................................... 295

Energy Efficiency Priorities ................................................................................ 297

Nuclear Energy .................................................................................................... 299

Future IPCC Reports ........................................................................................... 301

Appendix: Answers to Post-Hearing Questions

Dr. Mark D. Levine, Division Director of the Environmental Energy Technology Division at Lawrence Berkeley Laboratory ............................................ 304

Dr. William A. Pizer, Fellow at Resources for the Future and Senior Economist at the National Commission on Energy Policy ......................................... 306

Mr. Steven E. Plotkin, Transportation Energy Analyst with the Center of

Transportation Research at the Argonne National Laboratory ....................... 310

Dr. Roger A. Pielke, Jr., Professor of Environmental Studies Program at

the University of Colorado and Director of the Center for Science and

Technological Policy Research ............................................................................. 314

(1)

THE STATE OF CLIMATE CHANGE SCIENCE

2007: THE FINDINGS OF THE FOURTH ASSESSMENT REPORT BY THE INTERGOVERNMENTAL PANEL ON CLIMATE CHANGE

(IPCC), WORKING GROUP I REPORT

THURSDAY, FEBRUARY 8, 2007

HOUSE OF REPRESENTATIVES, COMMITTEE ON SCIENCE AND TECHNOLOGY, Washington, DC.

The Committee met, pursuant to call, at 10:00 a.m., in Room

2318 of the Rayburn House Office Building, Hon. Bart Gordon

[Chairman of the Committee] presiding.

2

3

HEARING CHARTER

COMMITTEE ON SCIENCE AND TECHNOLOGY

U.S. HOUSE OF REPRESENTATIVES

The State of Climate Change Science 2007:

The Findings of the Fourth Assessment

Report by the Intergovernmental Panel

on Climate Change (IPCC),

Working Group I Report

THURSDAY, FEBRUARY 8, 2007

10:00 A.M.–12:00 P.M.

2318 RAYBURN HOUSE OFFICE BUILDING

Purpose

On February 8, 2007, the Committee on Science and Technology will hold a hearing on the first section of the 2007 Assessment Report, Climate Change 2007: The

Physical Science Basis of Climate Change, prepared by Working Group I of the

Intergovernmental Panel on Climate Change (IPCC). Released in Paris, France, on

February 2, 2007, this document presents a comprehensive appraisal of the current

state of scientific knowledge of climate change.

The Committee will hear testimony from four witnesses who were involved in the

preparation of the Working Group I Report. The witnesses will present the findings

of the Report and discuss the relationship between the current findings and those

of past IPCC reports on the state of climate change science.

Key Findings of the 2007 Working Group I Report

On February 2, 2007 the Intergovernmental Panel on Climate Change (IPCC) released the first section of its Fourth Assessment Report, entitled ‘‘The Physical

Science Basis of Climate Change.’’

This first section of the IPCC Fourth Assessment Report builds upon information

contained in the previous reports. It updates information from the Third Assessment

Report based upon research conducted over the past six years. Uncertainties in

some areas have been reduced (e.g., quantitative estimates of radiative forcing). Climate models have improved, and expanded observations, data and information have

enabled the IPCC to increase the level of confidence in some earlier findings (e.g.,

attribution of warming to human-induced increases in greenhouse gas concentrations). In other areas (e.g., changes in frequency of tropical cyclones) uncertainties

remain and further research is needed to determine what patterns, if any, exist.

Despite remaining uncertainties, the Fourth Assessment Report represents a significant expansion in our knowledge of the influence of human activity on the

Earth’s climate. It is almost 30 years since the first international scientific conference on climate suggested that human activity could be impacting the Earth’s climate. This report confirms the original suspicions raised by scientists participating

in the 1979 climate conference as has every report of the IPCC from the first report

in 1990 to the present.

The 10 key findings in the 2007 report are:

• Atmospheric concentrations of greenhouse gases have increased significantly

due to human activities since 1750 due to fossil fuel use and land-use change.

• Our understanding of human-induced influences on climate has improved

since the 2001 Assessment. There is now very high confidence that Earth is

warming.

• Evidence that Earth is warmer includes: increase in global average air temperature and ocean temperature, widespread melting of snow and ice, and rising global average sea level.

• Long-term changes in climate have been observed including: changes in Arctic

temperatures and ice, changes in the amounts of precipitation, ocean salinity,

4

and wind patterns and changes in extreme weather events such as droughts,

heavy precipitation, heat waves, and intensity of hurricanes and typhoons.

• Changes in diurnal temperature ranges, Antarctic sea ice extent, meridional

overturning circulation of the global ocean, and localized extreme weather

events such as tornadoes, lightning, and dust storms have not been observed.

• The interpretation that the warming of the last 50 years is unusual in at

least the previous 1,300 years is consistent with paleoclimate information.

During the last period when polar regions were significantly warmer than

present for an extended period of time (about 125,000 years ago), reduced volume of polar ice led to sea level rise of four to six meters.

• Most of the observed increase in globally averaged temperatures since the

mid-twentieth century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations. Discernible human influences now extend to other aspects of climate, including ocean warming, continental-average temperatures, temperature extremes and wind patterns.

• Analysis of climate models coupled with constraints of observations enables

an assessed likely range to be given for climate sensitivity for the first time

and provides increased confidence in the understanding of the climate system

response to radiative forcing. The likely global average surface warming associated with a doubling of CO2 concentration is in the range 2 to 4.5°C. It is

very unlikely that climate changes of at least the seven centuries prior to

1950 were due to variability generated within the climate system alone.

• For the next 20 years a warming of 0.2°C per decade is projected for a range

of emission scenarios. Even if the concentrations of all greenhouse gases and

aerosols had been kept constant at year 2000 levels, a further warming of

about 0.1°C per decade would be expected.

• Continued greenhouse gas emissions at or above current rates would cause

further warming and induce many changes in the global climate system during the twenty-first century that would very likely be larger than those observed during the twentieth century.

Background

Prior to the establishment of the IPCC, the World Meteorological Organization

(WMO) convened two international meetings on greenhouse gas emissions and global climate. In 1979, the first World Climate Conference issued the following concern:

‘‘continued expansion of man’s activities on Earth may cause significant extended

regional and even global changes in climate.’’ In 1985 the United Nations Environment Program (UNEP), WMO, and the International Council for Science (ICSU) organized a joint conference on the ‘‘Assessment of the Role of Carbon Dioxide and

of Other Greenhouse Gases in Climate Variations and Associated Impacts.’’ This

conference concluded that ‘‘as a result of the increasing greenhouse gases it is now

believed that in the first half of the next century (twenty-first century) a rise of

global mean temperature could occur which is greater than in any man’s history.’’

In response to the findings of these earlier conferences, the IPCC was created by

WMO and UNEP in 1988. The IPCC was created to provide assessments of scientific, technical and socio-economic information relevant to understanding the risk

of human-induced climate change, its potential impacts and options for adaptation

and mitigation.

The IPCC is organized into a Plenary which meets once a year and is attended

by officials and experts from relevant ministries, agencies, and research institutions

from member countries and from participating organizations. This body makes the

decisions about preparation of new reports, their scope and content, and accepts reports prepared by expert teams. It elects the IPCC Chair, currently Rajendra K.

Pachauri, and the members of the IPCC Bureau. It also establishes IPCC principles

and procedures, designs the work plan and budget for the Panel and its activities.

The IPCC Secretariat is located in Geneva, Switzerland.

The IPCC relies upon primarily peer reviewed, published scientific and technical

literature. The IPCC also prepares special reports and technical papers on topics

where independent scientific information and advice is deemed necessary. The panel

operates within extensive peer review and governmental review, thus ensuring a

high level of transparency, scientific credibility, and policy relevance. Hundreds of

experts from around the world contribute to the assessment reports as authors, contributors, and reviewers. Participants are selected by the members of the IPCC Bureau (30 members each from a different nation) who are all elected for five to six

years and who are all experts in climate change. Participants may be nominated by

5

governments or participating organizations or they may be chosen due to their recognized expertise.

The IPCC published the First Assessment Report in 1990, Supplementary Reports

in 1992, a Special Report in 1994, a Second Assessment Report (SAR) in 1995, and

a Third Assessment Report (TAR) in 2001. Each of the assessment reports are comprised of three volumes from three corresponding working groups (I, II and III).

First Assessment Report

The First IPCC Assessment Report was completed in 1990 and provided policymakers with a comprehensive assessment of what was then known, and not known,

about human influence on climate. The report provided the main scientific basis for

the negotiation of the Framework Convention on Climate Change (UNFCCC). The

1992 United Nations Framework Convention on Climate Change was ratified by the

United States and called for a ‘‘non-binding,’’ voluntary goal for industrialized countries to stabilize their emissions of greenhouse gases at 1990 levels by the year

2000.

The 1990 IPCC report, as well as two Supplementary Reports (1992 and 1994)

supplied critical information for the United Nations Conference on Environment and

Development in Rio de Janeiro in June 1992. The Convention went into effect in

March 1994 and the first session of the Conference of the Parties (COP) was held

in Berlin in April 1995.

In the 1990 assessment, the authors’ wrote, ‘‘The size of the warming is broadly

consistent with predictions of climate models, . . .but the unequivocal detection of

the enhanced greenhouse effect from observations is not likely for a decade or

more.’’ The report projected an increase in average global temperature during the

twenty-first century of 0.3 degrees Celsius per decade and discussed the possible

consequences of that temperature change in relation to rising sea levels, increase

in extreme weather events, and serious pressure on aquatic and terrestrial ecosystems.

Second Assessment Report

Completed in 1995, the Second IPCC Assessment Report expanded on the findings

of the 1990 assessment. The Second Assessment Report stated that the climate of

the Earth had changed over the past century, increasing the global mean surface

air temperature somewhere between 0.3 and 0.6 degrees Celsius. The report stated

that climate was expected to change further in the future and projected an increase

of 1.0 to 3.5 degrees Celsius by 2100.

In the 1995 report, the IPCC concluded that ‘‘. . .the balance of evidence suggests

that there is a discernible human influence on global climate.’’ This second assessment provided key input to the negotiations that led to the adoption of the Kyoto

Protocol in 1997. More than 160 nations, parties to the Framework Convention on

Climate Change, adopted the Kyoto Protocol, with legally binding obligations to

limit emissions of industrialized nations for the years 2008 to 2012. The Protocol’s

emissions targets are hailed as important first steps toward the Framework Convention’s objective of avoiding dangerous climate change.

Third Assessment Report

The Third Assessment Report, ‘‘Climate Change 2001’’ consisted of three working

group reports on ‘‘The Scientific Basis,’’ ‘‘Impacts, Adaptation and Vulnerability,’’

and ‘‘Mitigation.’’ The findings also contained a synthesis report, which addressed

a range of policy relevant scientific and technical questions. This third report emphasized the findings from the previous five years and projected that average global

temperature would rise from 1.4 to 5.8 degrees Celsius over the next century. In

addition, authors explained how precipitation patterns are expected to change, the

degree to which sea level is expected to rise, and the possibility of the increases in

extreme weather events.

By the release of the 2001 report, confidence in the ability of models to project

future climate increased and authors concluded, ‘‘There is new and stronger evidence that most of the warming observed over the last 50 years is attributable to

human activities.’’ Furthermore, extensive and wide-spread evidence is present demonstrating that the Earth is warming and clear signals of a changing climate exist.

Witnesses

Dr. Susan Solomon of the National Oceanic and Atmospheric Administration (NOAA):

Dr. Susan Solomon serves as Co-Chair of Working Group I of the Intergovernmental Panel on Climate Change (IPCC), providing scientific information to the

United Nations Framework Convention on Climate Change. Her current research

6

includes climate change and ozone depletion, and she served as an overall coordinator for the report. After receiving her Ph.D. in chemistry from the University of

California at Berkeley in l98l, she has been employed by the National Oceanic and

Atmospheric Administration as a research scientist. Her scientific papers have provided not only key measurements but also theoretical understanding regarding

ozone destruction, especially the role of surface chemistry.

Dr. Solomon will provide an overview of the key findings of the report. Working

Group I’s contribution to the Fourth Assessment Report includes 11 chapters. Each

chapter has two Coordinating Lead Authors who are responsible for pulling together

the material for the chapter. In addition to the Coordinating Lead Authors, there

are a number of Lead Authors as well as numerous contributors and reviewers associated with each chapter.

Each of the other IPCC authors, Dr. Trenberth, Dr. Alley, and Dr. Meehl will discuss the findings with a focus on their respective chapters.

Dr. Kevin Trenberth of the National Center for Atmospheric Research

(NCAR):

Dr. Kevin Trenberth served as a Coordinating Lead Author for Chapter 3 of the

report entitled: Observations: Surface and Atmospheric Climate Change. Currently,

Dr. Trenberth is Head of the Climate Analysis Section at the National Center for

Atmospheric Research (NCAR) in Boulder, Colorado. From New Zealand, he completed his undergraduate degree in mathematics at the University of Canterbury,

Christchurch, New Zealand, and obtained his Sc.D. in meteorology in 1972 from

Massachusetts Institute of Technology, Cambridge, Massachusetts.

Dr. Richard Alley of the Department of Geosciences, Pennsylvania State

University:

Dr. Richard Alley served as a Lead Author for Chapter 4 of the report entitled:

Observations: Changes in Snow, Ice, and Frozen Ground. Dr. Alley is Evan Pugh

Professor of Geosciences and Associate of the Earth and Environmental Systems Institute at The Pennsylvania State University, University Park, where he has

worked since 1988. He received his Ph.D. in 1987 from the University of Wisconsin–

Madison and his M.Sc. (1983) and B.Sc. (1980) degrees from The Ohio State University–Columbus, all in Geology. Dr. Alley teaches, and conducts research on the climatic records, flow behavior, and sedimentary deposits of large ice sheets, to aid in

prediction of future changes in climate and sea level.

Dr. Gerald Meehl of the National Center for Atmospheric Research (NCAR):

Dr. Meehl is a Coordinating Lead Author for Chapter 10 of the report: Global Climate Projections. Dr. Meehl received his Ph.D. in Climate Dynamics from the University of Colorado in 1987. His expertise is in the field of climate modeling. He has

been a scientist on staff at NCAR since 1979. He has been a member of the Working

Group I Report Group since 1989 and has participated in the development of previous IPCC assessment reports.

Definitions:

Radiative forcing—an external disturbance in the radiative energy budget of

Earth’s climate system brought about by changes in atmospheric concentrations of

greenhouse gases, changes in solar radiation, or changes in the surface reflective

properties of Earth.

Meridional overturning circulation—the circulation system of the world’s

oceans driven by variations in temperature and salinity. Cold, dense water formed

in polar oceans sinks and is replaced by warmer, less dense surface water from temperate latitudes.

7

Chairman GORDON. Well, good morning, and welcome to this

hearing on the Intergovernmental Panel on Climate Change, or

IPCC, Report on the current state of our knowledge on climate

change.

This is the first opportunity Congress has to examine the findings of this important report.

The first warnings about the potential for climate change came

in 1979 when the first international conference on climate change

expressed the concern that human activity might lead to significant

regional and global changes in climate.

Now, almost 30 years later, increasing evidence confirms this

warning is real.

The importance of this report cannot be overstated. The Report

provides overwhelming evidence that global warming is real and

that human activity is the driving force.

The Report’s findings may be alarming, but it is not the work of

alarmists. The Report’s findings were endorsed unanimously by the

representatives of 113 nations, including the United States, and it

is the product of the work of nearly 300 scientists. In short, this

is a unanimous, definitive statement that global warming is real

and it is very likely that humans have contributed to it.

And let me just make that clear. This is a unanimous, definitive

statement. That meant that every nation, every scientist had to

agree to that. And so the Nation that might be the most naysaying,

the scientists that might be the most skeptical still had to agree

to this Report. So, at a minimum, this is a conservative report

about climate change.

The scientific experts have provided us with a diagnosis of the

problem and a prognosis for our nation’s health. If we continue

along our current path, the prognosis is ominous.

The scientists have done their job. Now, it is time for us, the policy-makers, to do ours.

We face a big challenge. We must explore ways to reduce emissions, to adapt to coming changes, and to mitigate the negative effects of climate change. We cannot accomplish all this overnight,

but we must begin in earnest now to address this serious issue.

And with some bit of irony, today, the Science Committee has a bill

of mine on the Floor in about an hour that will be the first bill that

will address renewable energy. We hope it will be—we don’t hope,

we know it will be the first of many bills.

The IPCC Report tells us that if we fail to act, our children, my

five-year old daughter, Dana’s triplets, Brian’s twins, and Madame

Speaker, your little four-month-old son, or grandson—you look

wonderful—they are all going to be affected, and they are going to

live in a very different world. And let me just say, this is not hypothetical. When you start talking about 10 years, 20 years, 50 years,

maybe 100 years, it seems like it is a long time off, but the actuaries tell us that our children are all going to live to the end of this

century. And certainly, our grandchildren are going to live beyond

that. So this is real. This is not hypothetical. We are talking about

something that is going to affect all of us in a very personal way,

because they are going to inherit a world which has much more severe droughts in some regions, greater flooding in others, and very

different coastlines due to a higher sea level.

8

And two days ago, my daughter spent the afternoon in my office.

We were looking out at the Capitol and I am hoping that when she

is older she is going to remember that view.

And I don’t want to look in my daughter’s eyes in 10 or 20 years

and try to explain why I didn’t take advantage of the opportunity

to address global warming while I was in Congress.

We need to improve existing technologies and to develop new

technologies and to reduce emissions and to make our economy and

our society more energy efficient. And we must understand the impacts of climate change on our ecosystems that support all life on

Earth.

Continued scientific research is imperative. We need better, more

refined regional assessments to understand the climatic

vulnerabilities of communities, ecosystems, and our economy. We

must continue to gather information on greenhouse gas emissions

and the Earth’s response to them and to further expand our understanding of climate and weather.

These four eminent scientists are a select few representing the

efforts of thousands of scientists from all over the world. And as

I said earlier, they have done their job. They have set the scientific

information before us. We must now move forward and act upon

this information.

We, on the Science and Technology Committee, can and must

play a role by ensuring that the science and research continue to

provide us the information we need to understand climate change

and to respond to it.

However, we must also begin with the information and tools in

hand today to adapt to the changing climate and to buy ourselves

time to adapt and to innovate by reducing emissions and energy

use.

We are world leaders in science and innovation. I intend for this

committee to ensure we maintain that leadership and lead the

world to address it with us.

On behalf of the Committee, I want to thank all of our witnesses

for joining us today and for the work you have done in preparing

this paper.

[The prepared statement of Chairman Gordon follows:]

PREPARED STATEMENT OF CHAIRMAN BART GORDON

Good morning and welcome to this hearing on the Intergovernmental Panel on

Climate Change (IPCC) report on the current state of our knowledge on climate

change.

This is the first opportunity Congress has to examine the findings of this important report.

The first warning about the potential for climate change came in 1979 when the

first international conference on climate change expressed the concern that human

activity might lead to significant regional and global changes in climate.

Now, almost 30 years later increasing evidence confirms this warning is real.

The importance of this report cannot be overstated.

The Report provides overwhelming evidence that global warming is real and that

human activity is driving this change.

The Report’s findings may be alarming, but it is not the work of alarmists.

The Report’s findings were endorsed unanimously by the representatives of 113

countries, including the United States.

And is the product of the work of nearly 600 scientists.

In short, it is a unanimous, definitive statement that global warming is real and

that it is very likely humans have contributed to it.

9

The scientific experts have provided us with a diagnosis of the problem and a

prognosis for our planet’s health. If we continue along our current path, the prognosis is ominous.

The scientists have done their job. Now, it is time for us—the policy-makers—to

do ours.

We face a big challenge. We must explore ways to reduce emissions, to adapt to

coming changes, and to mitigate the negative effects of a changing climate.

We cannot accomplish all this overnight, but we must begin in earnest now to address this serious issue.

The IPCC Report tells us that, if we fail to act, our children—my five-year-old

daughter, Dana’s triplets, and Brian’s twins—will live in a much different world.

A world with more severe droughts in some regions and greater flooding in others.

And much different coastlines due to a higher sea level.

Two days ago, my daughter spent the afternoon with me in my office. We were

looking out at the Capitol and I am hoping that when she is older, she will remember that view.

I don’t want to look in my daughter’s eyes in 10 or 20 years and try to explain

why I didn’t take advantage of an opportunity to address global warming while I

was in Congress.

We need to improve existing technologies and to develop new technologies to reduce emissions and make our economy and society more energy efficient.

And we must understand the impacts of climate change on the ecosystems that

support all life on Earth.

Continued scientific research is imperative. We need better, more refined regional

assessments to understand the climatic vulnerabilities of communities, ecosystems,

and our economy.

We must continue to gather information on greenhouse gas emissions and the

Earth’s response to them to further expand our understanding of climate and weather.

These four eminent scientists are a select few representing the efforts of thousands of scientists from around the world. As I said earlier—they have done their

job. They have set the scientific information before us. We must now move forward

and act upon this information.

We, on the Science and Technology Committee can and must play a role by ensuring that the science and research continue to provide us the information we need

to understand climate change and to respond to it.

However, we must also begin with the information and tools in hand today to

adapt to the changing climate and to buy ourselves time to adapt and innovate by

reducing emissions and energy use.

We are world leaders in science and innovation. I intend to ensure this committee

works to ensure we maintain that leadership. I believe we can meet this challenge

and we can, and should, lead the world to address it with us.

On behalf of the Committee, I want to thank all of our witnesses for agreeing to

come before us this morning. I believe most of you have just returned from the

meeting in Paris. We appreciate the work you have done and your willingness to

appear today.

Chairman GORDON. And at this time, I will recognize our very

distinguished Ranking Member, Mr. Hall, for an opening statement.

Mr. HALL. Good morning. And I thank you, and I thank the

Chairman for organizing this hearing about the very important

topic of global warming, or as some prefer to call it, climate change.

Let me start by thanking all of the witnesses for being here

today. This will be a key issue in the 110th Congress, and I hope

that I speak for all of the Committee Members in saying that we

appreciate the time that you all give us. Madame Speaker, we appreciate your appearing before us. I was amazed at the crowds outside there. At my age, I was fearful that someone had discovered

I might have been one of the Lindbergh kidnappers. I didn’t know

what everybody was doing there. But you are all welcome. I see

Sherry Boehlert, our former Chairman, in attendance, a great leader and a man that gave much of his time to this committee, and

to this Congress, and to this nation. Thank you, Sherry.

10

There will be a lot of debate in this Congress about what policies

the United States should adopt to deal with the potential impacts

of climate change. While today’s hearing is focused primarily on the

latest science related to climate change, it also is a public forum,

and I expect Members will stray from the science and offer their

opinions on various policy options that have been proposed.

So in that vein, let me set the record straight from the beginning.

I am skeptical about mandatory regulation of greenhouse gases,

which some of my colleagues are promoting as the best solution to

the problem of climate change.

As a nation, we can’t figure out how to write a cap-and-trade bill

that does not cause an immediate spike in natural gas prices, a

spike that endures for several years at the very least. The result

would be the closing of more factories, the closing of steel mills,

paper mills, lumber mills, and many others. Gas price increases

over the last six years, even without carbon regulation, have already caused millions of permanent layoffs. Factories won’t compete with utilities to buy gas. Rather, they will move to China and

India where there are no pollution controls, inevitably worsening

global emissions. In the meantime, Americans will be paying the

price.

Clearly, we need to make the American people fully aware of the

cost of mandatory emission caps. The discussion of mandatory caps

comes down to one question: what is the maximum cost to the U.S.

economy in dollars per family in a global warming bill, and what

is the minimum effect on world-wide temperatures our country is

willing to accept at such cost?

Of course, in order to fully answer that question, we will need

to factor into the equation the contribution, or lack of contribution,

of those countries who produce much of the pollution problems and

seem unwilling to be a part of the solution. I would like to see this

committee address this important equation in the near future.

We have an historic opportunity to use American innovation to

help address the problem, and our committee is poised to offer competitive solutions. I would like to see more discussions on how technology, especially alternative energy technologies, can help address

the issue of energy independence and climate change. I would also

like to explore how we can encourage the development of technologies to use existing domestic resources more cleanly, effectively, and efficiently. In fact, later this morning, we will be considering an alternative energy technology bill on the House Floor.

There is no limit to American innovation. When we put our minds

to solving a problem, we find answers that not only benefit our

country, but also the world. We have always been leaders in technology. This should be no exception. I would like to see this committee promote the development of a wide range of new technologies to help America become energy independent while maintaining our competitive edge in the world economy. In the end, innovation can do a lot, but only so much. World powers must absolutely do their part. Without this, there can be no true success in

solving the problem of global warming.

I look forward to hearing from our witnesses today and yield

back my time.

[The prepared statement of Mr. Hall follows:]

11

PREPARED STATEMENT OF REPRESENTATIVE RALPH M. HALL

Good morning. I am glad the Chairman organized this hearing about the important topic of global warming, or as some prefer to call it, climate change. Let me

start by thanking all of the witnesses for being here today. This will be a key issue

in the 110th Congress and I hope I speak for all the Committee Members in saying

we appreciate your time and the expertise that you can provide to our discussions.

There will be much debate this Congress about what policies the United States

should adopt to deal with the potential impacts of climate change. While today’s

hearing is focused primarily on the latest science related to climate change, it is also

a public forum and I expect Members will stray from the science and offer their own

opinions on various policy options that have been proposed. So, in that vein, let me

set the record straight from the beginning. I aim skeptical that mandatory regulation of greenhouse gasses, which some of my colleagues are promoting, is the best

solution to the problem of climate change.

As a nation, we can’t figure out how to write a cap-and-trade bill that does not

cause an immediate spike in natural gas prices—a spike that endures for several

years at the very least. The result will be the closing of more factories—steel, paper,

lumber and many others. Gas price increases over the last six years, even without

carbon regulation, have already caused millions of permanent lay-offs. Factories

won’t compete with utilities to buy gas. Rather, they will move to China and India

where there are no pollution controls, inevitably worsening global emissions. In the

meantime, Americans will pay the price.

Clearly, we need to make the American people fully aware of the costs of mandatory emission caps. The discussion of mandatory caps comes down to one question—

What is the maximum cost to the U.S. economy (in dollars per family) in a global

warming bill, and what is the minimum effect on worldwide temperature our country is willing to accept at such cost? Of course, in order to fully answer that question, we will need to factor into the equation the contribution, or lack of contribution, of those countries who produce much of the pollution problems and seem unwilling to be a part of the solution. I would like to see this committee address this

important equation in the near future.

We have an historic opportunity to use American innovation to help address this

problem, and our committee is poised to offer competitive solutions. I would like to

see more discussion of how technology, especially alternative energy technologies,

can help address the issue of energy independence and climate change. I would also

like to explore how we can encourage the development of technologies to use existing domestic resources more cleanly, effectively, and efficiently. In fact, later this

morning we will consider an alternative energy technology bill on the House Floor.

There is no limit to American innovation. When we put our minds to solving a problem, we find answers that not only benefit our country, but also the world. We have

always been leaders in technology—this should be no exception. I would like to see

this committee promote the development of a wide range of new technologies to help

America become energy independent while maintaining our competitive edge in the

world economy. In the end, innovation can do a lot, but only so much. World powers

must absolutely do their part. Without this, there can be no true success in solving

the problem of global warming.

I look forward to hearing from our witnesses today and yield back the balance

of my time.

Mr. SENSENBRENNER. Mr. Chairman, I have a parliamentary inquiry.

Chairman GORDON. The gentleman from Wisconsin.

Mr. SENSENBRENNER. My parliamentary inquiry, Mr. Chairman,

is are all of the witnesses that will appear today, including the distinguished Speaker, going to be subjected to questioning under the

five-minute rule, as required by House Rule 11?

Chairman GORDON. The gentleman raises a good question, but I

will excuse the Speaker after her opening remarks.

Mr. SENSENBRENNER. A further parliamentary inquiry. Is the

Chair aware that House Rule XI 2.(j)(2)(A) reads as follows: ‘‘Subject to subdivisions B and C, each Committee shall apply the fiveminute rule during the questioning of witnesses and the hearing

until such time as each Member of the Committee, who so desires,

has had an opportunity to question each witness.’’

12

Chairman GORDON. I am aware of it, and I ask unanimous consent that the Speaker be allowed to leave after her opening statement.

Mr. SENSENBRENNER. Mr. Chairman, I object, and I request that

House Rule 11, as cited, be applied, because it is mandatory.

Chairman GORDON. As the gentleman knows, anything can be

waived by unanimous consent.

Mr. SENSENBRENNER. Mr. Chairman, I object.

Chairman GORDON. Well, if that is your choice, then you will be

able to do that, and I am sure that the Speaker will give you a very

good answer.

Thank you, Mr. Hall. And Sherry Boehlert, as you can see,

things still don’t always change around here, but we welcome you

back. And you prove that you can come home, and that we are very

glad you are here.

I ask unanimous consent that all additional opening statements

submitted by the Committee Members be included in the record.

Without objection, so ordered.

[The prepared statement by Mr. Costello follows:]

PREPARED STATEMENT OF REPRESENTATIVE JERRY F. COSTELLO

Good morning. I want to thank the witnesses for appearing before our committee

to discuss the first section of the 2007 assessment report, Climate Change 2007: The

Physical Science Basis of Climate Change, prepared by the Working Group I of the

Intergovernmental Panel on Climate Change. This is a sobering report that demands our attention and I commend Chairman Gordon for moving quickly to hold

today’s hearing.

This report gives the Congress added momentum to take meaningful action to

combat global warming, and I look forward to working with my colleagues as we

craft such legislation. This process needs to be one of consensus, taking a wide view

of our current energy realities as well as the goals we need to reach in the future.

As the Working Group’s report states, ‘‘continued greenhouse gas emissions at or

above the current rates will cause further warming causing changes in the global

climate system.’’ Given the current state of scientific knowledge of climate change

and prior reports based upon six years of research, we need to work together to find

responsible solutions to take action to slow this trend.

Toward this end, we cannot ignore the reality that coal is going to play a role in

our nation’s energy supply and the world energy supply for years to come. Coal generates half of the electricity in this country and is a reliable domestic source of

power with a 250-year supply of coal in the U.S. alone.

To fully maximize our use of coal, we must continue to take steps that reduce

emissions. The only way to achieve this goal is through advancements in technology.

I have been a strong supporter of clean coal initiatives and programs to advance

the research and development needed to improve coal-based electricity generation.

Congress must continue to support the clean coal programs in the President’s FY08

budget, which includes the FutureGen Project, slated to be the world’s first zeroemissions coal plant. Among other things, FutureGen will demonstrate the ability

to sequester carbon dioxide emissions safely underground. The more coal plants

using clean coal technology equals less harmful emissions in our atmosphere and

a reduction of greenhouse gases.

Clean coal technologies do exist; however, they need the support and backing from

Congress to further develop and demonstrate their commercial viability. As we consider climate change legislation, I encourage my colleagues to include coal as part

of our energy solution. Again, I look forward to working with my colleagues as we

find practical solutions that lead us down the path of energy independence and protection of our environment.

I welcome the panel of witnesses and look forward to their testimony.

[The prepared statement by Ms. Johnson follows:]

13

PREPARED STATEMENT OF REPRESENTATIVE EDDIE BERNICE JOHNSON

Thank you, Mr. Chairman. Today’s hearing brings representatives of an important body of scientific knowledge on the state of science regarding climate change.

The Intergovernmental Panel on Climate Change (IPCC) has spent hundreds,

maybe thousands of hours preparing this report. The Panel gathered the world’s

leading experts on Earth science and surveyed the literature.

The Panel took comments from the greater scientific community. All of this work

has resulted in a high quality product that policy-makers should take seriously.

I have been frustrated by the lack of action—real action—in dealing with climate

change from the legislative standpoint.

Why don’t we mandate stricter standards to that all automobiles run on a greater

number of miles per gallon of gasoline? Why haven’t we passed into law good ideas

such as the Chairman’s on alternative fuel research and development?

Why haven’t we explored and utilized more of our domestic oil resources in the

short-term, while investing heavily in solar, wind, nuclear, hydrogen fuel research

and development?

Why haven’t we provided more incentives for the American people to buy fuel-efficient or hybrid vehicles?

The number of unanswered questions of this nature keeps growing.

I am eager to hear what today’s witnesses have to say, and I thank the Chairman

for inviting them to testify today.

[The prepared statement by Mr. Lipinski follows:]

PREPARED STATEMENT OF REPRESENTATIVE DANIEL LIPINSKI

I am pleased that with this hearing today, we will continue the discussion on the

issue of global climate change in the House Committee on Science and Technology.

The science on climate change has come a long way since the first international

scientific conference on climate almost 30 years ago. This fourth assessment report

by the IPCC represents a significant expansion in our knowledge of the influence

of human activity on the Earth’s climate. The solid scientific conclusions reached in

this report allow us to move beyond debating whether humans are affecting climate

change, and let us begin the discussion of how to resolve the dilemma before us.

The challenges we face, which are documented in dramatic scientific detail within

this report, highlight the need to act and act now. The need to find cleaner, less

polluting sources of energy to reduce our impacts on climate change offers us a future of great opportunities, especially as we seek to compete in the global economy

of the 21st Century.

Fortunately, feasible approaches to reducing carbon dioxide emissions are no

longer out of reach. In the 109th Congress, the House Committee on Science heard

from U.S. businesses that had implemented energy efficient practices and manufacturing changes to reduce greenhouse gas emissions. I applauded the voluntary actions of these businesses for taking the lead even in the absence of mandatory requirements.

This is a global challenge, and we must do our part to see that the health of our

planet does not deteriorate further. As such, we must work on providing greater incentives to all U.S. businesses so they will continue to develop new environmentally

friendly technologies and implement further reductions in greenhouse gas emissions.

I look forward to the release of the Working Group II and Working Group III reports later this spring and welcome the chance to learn how we might go about mitigating global climate change. It is my hope that creative and vigorous dialogue in

the 110th Congress will yield concrete results that will put us on the right path toward a more sustainable future.

[The prepared statement by Mr. Ross follows:]

PREPARED STATEMENT OF REPRESENTATIVE MIKE ROSS

I would like to first thank Chairman Gordon and Ranking Member Hall for holding today’s hearing on climate change. I would also like to thank Speaker Pelosi for

coming before the Committee today and all of the witnesses who have come here

to discuss their findings on this topic.

I am honored that our committee will be the first to hear from the authors of the

Intergovernmental Panel on Climate Change’s Report on Global Climate Change.

I strongly believe that our nation must develop a comprehensive plan that combats climate change by investing in alternative and renewable fuels and reducing

greenhouse gas emissions and I am hopeful that today’s hearing will continue the

14

discussion of climate change to aid in this process. I also believe in a common sense

approach to imposing regulations that will help to improve our environment and

combat the harmful effects of global warming, while maintaining jobs and strengthening our nation’s economy.

I am hopeful that all of these goals can be met and I look forward to today’s discussion of the IPCC’s report, which will provide great insight into this topic.

[The prepared statement by Mr. Carnahan follows:]

PREPARED STATEMENT OF REPRESENTATIVE RUSS CARNAHAN

Mr. Chairman, thank you for placing this important hearing first on the calendar

of the Committee on Science and Technology for the 110th Congress. By prioritizing

it on our agenda, you have helped to emphasize the growing importance of climate

change on the national debate.

Speaker Pelosi, it is a tremendous honor to have you appear before us today and

I look forward to hearing your testimony on the state of climate change. Your presence speaks loudly to your commitment to bipartisan action on this very important

issue. Thank you for joining us.

The conclusions of the Intergovernmental Panel on Climate Change (IPCC) have

clarified that human-induced influences impact the climate. With very high confidence, the IPCC now tells us that the Earth is warming as is indicated by an increase in global average air and ocean temperature, widespread melting of snow and

ice, and rising global average sea level. While this news is unfortunate, the certainty with which science now warns that human actions are impacting the climate

should motivate the Congress to move forward on legislative solutions.

I am proud to say that last Congress I was very active on the issue of global

warming, introducing a bipartisan and bicameral Sense of Congress resolution,

H.Con.Res. 453, aimed at addressing global warming through the negotiation of

international treaties. Furthermore, during debate on the 2005 Energy bill, I attempted to amend the bill by redrafting and extending the Hybrid tax credit, a credit that was eventually enacted into law and is a step forward in our efforts to stem

harmful emissions.

St. Louis has one of the highest rates of asthma and respiratory diseases in the

country, the causes of which are directly related to global warming. For this reason,

climate change is an issue of vital importance to my constituents.

I look forward to hearing the testimony of Speaker Pelosi and the IPCC witnesses

and participating in the conversation of climate change as we deliberate over legislative solutions in the 110th Congress. Thank you all for being here today.

[The prepared statement by Mr. Mitchell follows:]

PREPARED STATEMENT OF REPRESENTATIVE HARRY E. MITCHELL

Thank you, Mr. Chairman.

I think one of the things the American people are hoping from this Congress is

for Democrats and Republicans to work together to take the threat of global warming to our environment and our national security seriously.

We are watching our planet rapidly change before our eyes. Once majestic ice caps

are melting. Weather patterns are changing in very troubling ways. The temperature of our atmosphere is on the rise. The intensity of rains and drought are more

extreme. Hurricanes, such as Katrina, are becoming more powerful, and more deadly.

The scientific evidence that global warming exists—and that humans are largely

responsible for the change in our climate—is overwhelming.

The report by the Intergovernmental Panel on Climate Change—which we are

hearing more about today—continues to confirm our fears about global warming.

I hope that as the American people and the international community continue to

learn about this report and the effects of global warming, our renewed interest in

the topic will turn into action.

The United States is the world leader in the emission of greenhouse gases. That

means we have a moral obligation to lead the world to a solution.

I believe that America’s ingenuity, and our unique spirit can be an incredible

asset in this cause. Our action on global warming can also help restore our authority as a respected global leader.

Developing sound policy on global warming—and investing in new technologies

and clean energy—can help grow our economy too.

This Congress, the President and the American people have a responsibility, and

I hope that we re-dedicate ourselves to meeting that responsibility.

15

[The prepared statement by Mr. Ehlers follows:]

PREPARED STATEMENT OF REPRESENTATIVE VERNON J. EHLERS

I am pleased that the Science and Technology Committee is hearing from scientists who participated in the Intergovernmental Panel on Climate Change, especially so soon after the Summary for Policy-makers was released. We’re fortunate

to receive this information ‘‘hot off the presses’’ (if I am allowed to think that anything ‘‘hot’’ is a good thing given today’s topic).

In my mind, there are three big questions related to climate change. One, is climate change happening? Two, to what extent is it anthropogenic? And three, what

are we going to do about it? I believe that the research the panelists will discuss

today advances our knowledge of the answers on the first and second of these questions. We need to hear how the methods of monitoring changes in the Earth have

improved, and what the most recent data indicates, especially since the last major

assessment was finalized in 2001. But an even bigger task for this committee and

our colleagues is to answer the third question: what are we going to do about climate change? Comprehensive and continuing science is critical for us to be able to

answer that question. The additional working groups of the IPCC also will help address the broader policy questions of climate change strategy, and I look forward

to reviewing those results in the spring.

Our planet is a dynamic system, and any attempts to mitigate warming, adapt

to sea level rise, or any other response to climate change will rely on scientific research and researchers, like those testifying before us today. These individuals have

dedicated not just hours, but years to the process that results in the full assessment

of climate science due in May. I thank them for that commitment, and look forward

to the opportunity to hearing what they have to say.

[The prepared statement by Mr. Neugebauer follows:]

PREPARED STATEMENT OF REPRESENTATIVE RANDY NEUGEBAUER

Mr. Chairman:

Thank you for holding this hearing. I welcome the opportunity to take part in this

important discussion and look forward to hearing from our distinguished panelists.

Like everyone else, and despite the recent record cold temperatures here in DC

and around the country, I believe the Earth has gotten warmer over the past century. I don’t doubt that there is consensus on that fact. Beyond that, however, I see

a lot of disagreement.

On the one hand, we have the distinguished scientists before us who have authored key findings of the IPCC’s report. They—and others—believe ‘‘with more

than 90 percent confidence’’ that, based on their models and data, human activity

is chiefly responsible for global warming since the 1950s.

On the other hand, we have other distinguished scientists who disagree with that

assessment. Some believe that humans, to varying degrees, have played a role in

global warming. Others believe that solar activity has been the primary factor, given

their models and data.

The bottom line, Mr. Chairman, is that the scientific community does not speak

with one voice on this important issue. And that’s not unusual. It happens all the

time with scientific inquiry. New models are developed; data is re-examined; new

hypotheses are tested. That’s normal and healthy—when you have a robust scientific community free of political or ideological interference.

But Mr. Chairman, what I’ve seen lately has been disturbing—and it should concern every American. Scientists who disagree with the popular view on global warming are being ostracized. They are being labeled ‘‘global warming deniers.’’ We have

politicians and activists—most of whom are not scientists themselves—working to

silence highly trained and accredited scientists. Some call for silencing their disagreement by revoking professional certifications and removing them from key positions.

Mr. Chairman, why has the reaction to these differing scientific findings been so

extreme and so reckless? I strongly suspect that ideology, not scientific disagreement, is behind this reaction.

Mr. Chairman, it is an inconvenient truth that we run a terrible danger when scientific debate is stifled because it gets in the way of political goals.

We in Congress, and in this committee especially, are called upon to make scientific and environmental policy that will affect our economy, our security, and our

general welfare; and not just for us, but for future generations of Americans, as

well.

16

To the best of my knowledge, none of us sitting on this committee are climatologists or meteorologists or otherwise competent on our own merits to claim full

knowledge of this complex issue. So, we deserve to have all the scientific information before us—to consider it, and to make the wisest policy choices based on all

the findings before us.

Mr. Chairman, you have indicated that it’s time to end the debate on this issue.

But I respectfully disagree with that assessment. It is plain that the debate has just

begun.

I hope future hearings on global warming will provide the opportunity to hear opposing views and have a full healthy debate and dialogue on this issue.

Thank you.

Chairman GORDON. I ask unanimous consent that Representative Gilchrest, who was a former Member of this committee, be permitted, at his request, to sit at the dais for this hearing and that

he be permitted to ask questions after all Members of the Committee have an opportunity to question the witnesses. Mr. Sensenbrenner, is that okay with you?

Mr. SENSENBRENNER. I just want to see the rules followed.

Chairman GORDON. All right. Thank you. Without objection, so

ordered.

Now it is my pleasure and privilege to welcome the Speaker of

the House of Representatives, Nancy Pelosi, to be with us today.

I know this is an issue that you are both informed about and have

a passion about. And we welcome you here for this hearing and

welcome to hear your remarks.

Panel I:

STATEMENT OF THE HONORABLE NANCY PELOSI, SPEAKER

OF THE HOUSE OF REPRESENTATIVES

Speaker PELOSI. Thank you very much, Mr. Chairman.

I thank you and your distinguished Ranking Member, Mr. Hall,

for the courtesy extended here today for me to present my views

before this very important committee.

The last time I was in this room was for the unveiling of the portrait of Mr. Boehlert, and here we are, portrait and Mr. Boehlert,

as well, and I join you in thanking him for his great leadership to

our country and in working in a bipartisan way to use science as

a basis for progress in our country.

I want to also join in commending the witnesses who will be presenting today. I thank them for their extraordinary contribution to

understanding of climate change. Their new report confirms that

climate change is indisputably underway and states with 90 percent certainty that greenhouse gases released by human activities

are the main cause of global warming.

I am very pleased to see on the wall, which in the excitement of

Mr. Boehlert’s unveiling, I didn’t see that day several months ago,

that you quote Tennyson, who is my favorite poet, Alfred Lord Tennyson. And it says, ‘‘For I dipped into the future, as far as human

eyes could see, saw the vision of the world and all the wonder that

would be.’’ What a wonderful inspiration to the work of this committee.

You, on this committee, are opening a window into our future.

Looking through that window, we see a future in which global

warming will reshape our planet and our society. We also see a fuVerDate 11-MAY-2000 16:09 May 12, 2008 Jkt 032966 PO 00000 Frm 00028 Fmt 6633 Sfmt 6601 C:\WORKD\FULL07\020807\32966.TXT SCIENCE1 PsN: SCIENCE1
17

ture in which harsh consequences could be blunted by prompt action. That is the good news.

This is an issue that is as immediate to the American people as

their own neighborhoods and as global as the planet itself. It was

interesting to me that on a recent visit from the Executive Committee of the U.S. Conference of Mayors, a bipartisan Committee,

they brought forth their 10-point program for strong cities, strong

families, a strong America. And point number one in the Conference of Mayors’ 10-point proposal was energy independence, climate change, global warming. That was their top priority. They

had best practices, that they, in a bipartisan way, are sharing with

each other and instituting in their communities. Again, this is as

immediate to the lives of the American people as their own neighborhoods, and again, it is as global as the planet. And that—more

on that in just a moment.

On the science of global warming, the level of carbon dioxide in

the atmosphere is by far the highest in 650,000 years. Temperatures are estimated to rise anywhere from two degrees Fahrenheit

to as high as 11.5 degrees by the end of the century. We can expect

rising sea levels, more intense storms, increased drought in some

areas and more floods in others, heat waves, spread of tropical diseases, extinction of species, changes in ocean salinity, and melting

ice in the polar regions, and that is already happening.

The catastrophic hurricanes of 2005, Katrina and Rita, foreshadow the challenges we will face. All along our coastlines, our

great cities and small towns will be threatened by rising sea levels

and intensifying storms.

Not only coastal areas will be affected. Inland communities will

be gravely affected as well by drought and flood. Movement of climate change refugees from one country to another could increase

political instability in many regions of the world. These environmental refugees are a real, real concern.

Looking through the window into the future that you have

opened, we also see that we can reshape our activities now and

prevent catastrophic global warming. Where once we thought the

effects of global warming would occur decades away, change is already underway.

We hold our children’s future in our hands, not our grandchildren, or great-grandchildren, but our own children. As the most

adaptable creatures on the planet, it is time for us to continue to

adapt.

Scientific evidence suggests that to prevent the most severe effects of global warming, we will need to cut global greenhouse gas

emissions roughly in half from today’s levels by 2050. The Bush

Administration continues to oppose mandatory limits on greenhouse gases, restating this position immediately upon the release

of the IPCC report. I respectfully disagree with the distinguished

Ranking Member in his comments, and this is a wonderful venue

for the debate, this very important committee with these very informed Members.

I do believe, though, Mr. Hall and Mr. Chairman, we cannot

achieve the transformation we need, both in the United States and

throughout the international community, without mandatory action

to reduce greenhouse gas pollution. Many of the technologies to

18

revolutionize our use of energy are already at hand, as the distinguished gentleman mentioned, and we can develop others, waiting

on the shelf, or under development. Restrictions on greenhouse gas

emissions will drive these technologies into the marketplace quickly and cost-effectively, while simultaneously creating the next generation of good-paying new jobs.

In addition, we must address land-use policies in the U.S. and

worldwide, since the loss of forests currently contributes about 25

percent of global carbon dioxide emissions. Older forests can store

more carbon while also providing fuel for biomass energy in a sustainable manner.

We have a responsibility to work together with countries, as the

distinguished Ranking Member Mr. Hall said, but these other

countries, India and China, to name two, to work with them for

them to reduce the level of carbon dioxide in the atmosphere. That

may be as important to our grandchildren and our children’s future

as anything we do here. The United States and China, as well as

India, are the largest contributors of carbon dioxide emissions in

the world, and it is estimated that China will surpass the United

States in three years.

We need to engage the Chinese government by working cooperatively to develop clean and renewable sources of energy.

I have asked the Chairs of the committees of jurisdiction to work

with their Ranking Members in a bipartisan way with the Members of the Committees to develop legislation over energy, environment, and technology policy and to report that legislation to us no

later than June 1 so that we can have an energy independence

global warming package by the 4th of July.

This committee is way ahead of the rest. It has legislation, as

has been mentioned, on the Floor today, and I commend you for

that, Chairman Gordon and Mr. Hall and Members of the Committee. I know that you have other legislation that relates to innovation and the innovation agenda, which is directly related to this

issue that will help advance the technologies needed to help save

our planet.

We hope to have legislation that will be a starting point on global

warming and energy independence soon. Again, you have taken the

lead.

I also want to mention that we are creating a Select Committee

on Energy Independence and Global Warming to raise the visibility

of these urgent issues and gather critical information to protect

America’s security. This is a national security issue. The Select

Committee will not have legislative jurisdiction, but will develop

policy strategies, technologies and other innovations intended to reduce the dependence of the United States on foreign sources of energy, and to achieve substantial and permanent reductions in emissions and other activities that contribute to climate change and

global warming. The Select Committee will share its findings with

the legislative committees of the House and with the public, and

they will make a special effort to communicate with younger Americans by using the most cutting-edge technologies. Young people

are very concerned about the issue of global warming. It is natural,

because the future is theirs, and this has a big impact on the future.

19

For 12 years, the leadership in the House of Representatives has

stifled all discussion and debate on global warming. The long rejection of reality is over, to the relief of Members, I believe, on both

sides of the aisle.

We teach our children, Mr. Chairman and Ranking and other

Members of the Committee, that everything in nature is connected,

and indeed, it is. The Bible tells us in the Old Testament that, ‘‘To

minister to the needs of God’s creation is an act of worship. To ignore those needs is to dishonor the God who made us.’’ Indeed, this

planet is God’s creation. That is why large segments of the evangelical movement have become part of this effort to curb and stop

global warming. We have a responsibility to make an act of worship by protecting God’s creation.

There is a growing chorus of voices, including evangelicals, in

favor of taking serious and sustained action on global warming,

from scientists to Fortune 100 CEOs, from evangelical Christians

to environmentalists, from farmers to hunters and anglers. We will

work together, holding hearings, developing legislation, and tackling one of America’s—humanity’s—greatest challenges yet: global

warming.

With that, Mr. Chairman, I thank you, once again, for the opportunity to present my views as Speaker of the House to you and to

Mr. Hall with the promise that this is not about taking one point

of view and going forward but in trying to work in a bipartisan way

for sustainable initiatives that we can agree upon and make a difference for our children and see ‘‘the vision of the world and all the

wonder that would be’’ in this important committee. Thank you,

Mr. Chairman.

[The prepared statement of Ms. Pelosi follows:]

PREPARED STATEMENT OF SPEAKER NANCY PELOSI

Thank you, Chairman Gordon, for holding this important hearing on the findings

of the Fourth Assessment Report by the Intergovernmental Panel on Climate

Change (IPCC). Thank you, Ranking Member Hall, and my colleagues on the

Science and Technology Committee for your attention to the pressing issue of climate change.

To the witnesses appearing today, thank you for your extraordinary contributions

to our understanding of climate science. Your new report confirms that climate

change is indisputably underway and states with 90 percent certainty that greenhouse gases released by human activities are the main cause of global warming.

You have opened a window into our future. Looking through that window, we see

a future in which global warming will reshape our planet and society. We also see

a future in which harsh consequences could be blunted by our prompt action.

The level of carbon dioxide in the atmosphere is by far the highest in 650,000

years. Temperatures are estimated to rise anywhere from two degrees Fahrenheit

to as high as 11.5 degrees by the end of the century. We can expect rising sea levels,

more intense storms, increased drought in some areas and more floods in others,

heat waves, spread of tropical diseases, extinction of regions.

The catastrophic hurricanes of 2005, Katrina and Rita, foreshadow the challenges

we will face. All along our coastlines, our great cities and small towns will be threatened by rising sea levels and intensifying storms.

Not only coastal areas will be affected. Inland communities will be gravely affected as well by drought and flood. Movement of climate change refugees from one

country to another could increase political instability in many regions of the world.

Looking through the window into the future that you have opened, we also see

that we can reshape our activities now and prevent catastrophic global warming.

Where once we thought the effects of global warming would occur decades underway.

20

We hold our children’s future in our hands—not our grandchildren, or greatgrandchildren, but our own children. As the most adaptable creatures on time for

us to adapt.

Scientific evidence suggests that to prevent the most severe effects of global

warming, we will need to cut global greenhouse gas emissions roughly in half from

today’s levels species, changes in ocean salinity, and melting ice in the polar away,

change is already the planet, it is by 2050. The Bush Administration continues to

oppose mandatory limits on greenhouse gases, restating this position immediately

upon the release of the IPCC report.

We cannot achieve the transformation we need, both in the United States and

throughout the international community, without mandatory action to reduce greenhouse gas pollution. Many of the technologies to revolutionize our use of energy are

already at hand, waiting on the shelf, or under development. Restrictions on greenhouse gas emissions will drive these technologies into the marketplace quickly and

cost-effectively, while simultaneously creating the next generation of good-paying

new jobs.

In addition, we must address land-use policies in the U.S. and worldwide, since

the loss of forests currently contributes about 25 percent of global carbon dioxide

emissions. Older forests can store more carbon while also providing fuel for biomass

energy in a sustainable manner.

We have a responsibility to work together with countries such as China to reduce

the level of carbon dioxide in the atmosphere. The United States and China are the

two largest contributors of carbon dioxide emissions in the world and it is estimated

that China will surpass the U.S. in just three years.

We need to engage the Chinese Government by working cooperatively to develop

clean and renewable sources of energy.

I have also asked the committees that have jurisdiction over energy, environment

and technology policy to report legislation on these issues by June. We hope to have

legislation that will be a starting point on global warming and energy independence

through the committees by July 4th, so that this year, Independence Day is also Energy Independence Day.

We are creating a Select Committee on Energy Independence and Global Warming to raise the visibility of these urgent issues and gather critical information to

protect America’s security. The Select Committee will not have legislative jurisdiction, but they will develop recommendations on policies, strategies, technologies and

other innovations intended to reduce the dependence of the United States on foreign

sources of energy, and to achieve substantial and permanent reductions in emissions

and other activities that contribute to climate change and global warming. The Select Committee will share its findings with the legislative committees of the House

and with the public, and they will make a special effort to communicate with younger Americans by using the most cutting-edge technology.

For twelve years, the leadership in the House of Representatives stifled all discussion and debate of global warming. That long rejection of reality is over, to the relief

of Members on both sides of the aisle.

The Bible tells us in the Old Testament, ‘To minister to the needs of God’s creation is an act of worship. To ignore those needs is to dishonor the God who made

us.’

There is a growing chorus of voices in favor of taking serious and sustained action

on global warming: from scientists to Fortune 100 CEOs, from evangelical Christians to environmentalists, from farmers to hunters and anglers. We will work together, holding hearings, developing legislation, and tackling one of humanity’s

greatest challenges yet global warming.

DISCUSSION

Chairman GORDON. Speaker, thank you for joining us today. You

are the first Speaker to be before this committee. I have only been

here 22 years, but you are the first Speaker that I know of in those

22 years to make a presentation before any committee, and I suspect this may be groundbreaking in the history of the Congress,

which I think demonstrates your passion and leadership on this

issue, and we appreciate you being here.

My Ranking Member Hall and I have no questions. We are going

to let Mr. Sensenbrenner have his question, and then I am going

21

to ask that we have unanimous consent that any further questions

be submitted by writing.

Mr. Sensenbrenner.

Well, then Mr. Sensenbrenner will have the first question.

ECONOMIC IMPACTS OF CLIMATE CHANGE

Mr. SENSENBRENNER. Thank you very much, Madame Speaker.

Speaker PELOSI. Thank you, Mr. Sensenbrenner.

Mr. SENSENBRENNER. I welcome you here today.

Speaker PELOSI. Thank you.

Mr. SENSENBRENNER. I hope that you and your successors engage

in the debate on the issues before the Congress, and I think that

this is a very welcome development.

I really do have to take issue with your comment in your statement that for 12 years there was no discussion of global warming,

because during my chairmanship of this committee, and particularly in 1998 and 1999, we had a number of hearings at the Full

and Subcommittee level relative to the Kyoto protocol, the science

behind it, and the economic consequences this ratification would

entail to the United States and its workers. One of those witnesses

was the head of the Energy Information Agency in the Department

of Energy who was a direct appointee of President Clinton. And

this man testified that the ratification of Kyoto and the caps that

are similar to that which you are advocating, would cause a 60 to

80 percent increase in the cost of natural gas, electricity, and fuel

oil to the American consumer. And given the fact that China is not

under any caps and as late as last week said that they didn’t want

to do that, I would ask you to look at the impact on American jobs,

because we do not want to have anything we do result in the

outsourcing of American jobs to countries like China and India and

Mexico that have not capped or even slowed down their growth in

greenhouse gas emissions. What are you planning to do, Madame

Speaker, to make sure that we don’t legislate on this area in a way

that wrecks the American economy and costs our workers jobs?

Speaker PELOSI. Thank you, Mr. Sensenbrenner.

Whatever actions we take have to be based, I believe, on science

and on the facts. And one fact is that America must innovate in

this arena for us to be ahead. We look forward to doing this in a

bipartisan way. We know that there will be impacts on the coal industry, on other sources of energy, and we want to hear what those

industries have to say. So this isn’t about running roughshod. This

is about working together. And hopefully we can work in a bipartisan way with the President of the United States in order to do

this. I see it as an economic opportunity, a place where green can

be gold for our country where the technologies we develop for dealing with the coal industry and other industries in our country on

which we are dependent now for energy using their initiatives, because they are making change, and we have to listen to them as

well, to Mr. Rahall and Mr. Boucher, who represent these districts,

Members of the Republican party who represent them as well.

So what we want to do is do something where we have as much

unity as possible, and we certainly are sensitive to the issue of economic growth in our country.

22

Mr. SENSENBRENNER. Well, Madame Speaker, just to follow up,

I would make the observation that there are two sides to the equation. One is the scientific side and relative to emissions of greenhouse gases. The other is the economic consequences of any actions

that we take. And you know, I am very fearful the way this debate

has been joined and, given who the witnesses are following you,

that we are looking at one side of the equation and ignoring the

other side, and we can’t do that for the sake of American jobs.

And I yield back the balance of my time.

Speaker PELOSI. Yes, I agree with that, Mr. Sensenbrenner. We

can’t ignore it, but we also can’t ignore the consequences of not

doing something, because that will have an economic impact as

well.

SELECT COMMITTEE ON ENERGY INDEPENDENCE AND

GLOBAL WARMING

Chairman GORDON. Thank you. Mr. Sensenbrenner, I will point

out that the Minority had the right to submit witnesses. I think

that you had one. You withdrew him. And so this was not a rigged

jury, but rather it may be by default. Maybe no one else wanted

to come up and speak. But that is where we are.

Madame Speaker, as we gather together here, I know you had

mentioned earlier, again, your passion for this and that you wanted

to develop a Select Committee. Could you tell us more about that

Select Committee and why it is so important and what you want

to do with it?

Speaker PELOSI. Thank you, Mr. Chairman.

There are eight or nine committees of jurisdiction on this issue

ranging from this important committee, the Ways and Means Committee, the International Relations Committee, as has been pointed

out by Mr. Sensenbrenner, and the distinguished Ranking Member,

other countries have a big impact on how we go forward on this

issue. And so this Select Committee was designed to try to get

some of the best information possible by communicating directly in

the cities of America where, again, best practices are being used to

address this issue, where the bipartisan Conference of Mayors is

putting forth global warming and energy independence as their top

priority in their 10-point program, working with the governors,

working with leaders around the world. The European Union is

way ahead of us on this issue. They see it as an economic issue,

Mr. Sensenbrenner. They see it as an economic issue. They know

that they want to be out there in front with the technologies that

will enable us to curb global warming, and that is in our economic

interest. The United Nations, of course we have this report, but the

United Nations has this as a priority as well.

I have asked this—a Select Committee to—whether it is as local

as a neighborhood, as global as the planet, to help communicate

this message, get the best possible information. I could have done

it as a task force within the Democratic party, but I wanted it to

be bipartisan so we had every point of view represented, different

views in our own party as well as views within the Republican

party so that as we go forward, we are doing so in a way that is

understanding the consequences of it.

23

So it is a way for us to communicate with the next generation

of leaders in our country, to communicate with countries that have

a big impact on global warming like China and India, communicate

to the neighborhoods of America that everyone is involved in this

decision, because everyone is affected by it. And we want to go forward in a temperate way but in a bold way to make a difference

for our children.

So that is the purpose of it. It does not have legislative authority.

It will end at the end of this Congress, and I think it will be a force

for good.

Chairman GORDON. Mr. Hall.

Mr. HALL. Mr. Chairman, I have no questions for this speaker.

And we did invite, from the United States Chamber of Commerce

one of the great bodies of advice for this committee. They said they

did not have the time to answer the political questions. They

thought it was going to be on science alone. It is not that. And we

will have them before you later.

I yield back any time that you might yield to me.

Chairman GORDON. Well, Mr. Hall, I think you will find that the

IPCC Report is the scientific definitive statement on this issue and

we look forward to hearing that.

Let us see. Is there anyone else on the top row?

Mr. Akin.

NUCLEAR ENERGY

Mr. AKIN. Thank you, Mr. Chairman.

And I appreciate your allowing us to ask a few questions. And

it is a very interesting debate. Madame Speaker, thank you for

joining us this morning.

Speaker PELOSI. Thank you.

Mr. AKIN. Your comments, you laid out a couple of basic premises that you were assuming. The first premise is that the Earth

is getting warmer. I don’t think there is a lot of debate on that. I

think the Earth is getting warmer.

The second one is maybe another question that is interesting. It

is being caused by our burning hydrocarbons. If, in fact, you apparently believe that to be true, my question is, do you endorse the

expansion of nuclear energy, because that does not burn hydrocarbons?

Speaker PELOSI. Mr. Akin, in the early days of my life in the

Congress, I was an opponent of nuclear energy, because I didn’t

know what was going to be done—how we would dispose of the

waste from it.

Your question is a good one, because the technology has changed,

and I bring a more open mind to that subject now, because I think

we have to look at the technology and really compare it to what

the alternatives. If they are looking at India and we are looking at

China and looking at them putting on more coal-burning plants

than we have in the United States, that they are just going to even

add now, and the alterative might be nuclear, we have to weigh

what that does to the environment. But I think that the answer is

always with technology. If we can’t—if the technology is at a place

where we can dispose of the waste, well, let us at least try to move

24

it to that place. But I have a different view of nuclear energy than

I did, say, 20 years ago when I came to this——

Mr. AKIN. I think what I hear you saying is that you would—assuming that a reasonable proposal could be made, that nuclear

could be the substitute for burning hydrocarbons.

Speaker PELOSI. Well, I would say I would not, as I did in my

youth, be an active opponent of such a thing, but hope that we

would work together to take it to a place where we can dispose of

the waste. That is the big challenge. But I will say this. Again, we

have to always compare it to if not this, then what, and what does

that do in terms of global warming. So I think it has to be on the

table.

Mr. AKIN. That is interesting. I appreciate your open-mindedness

to that alternative.

Speaker PELOSI. I do have an open mind.

THE INTERNATIONAL BANKING ENVIRONMENTAL

PROTECTION ACT

Mr. AKIN. That is something from an engineering perspective—

I am one of the few engineers, I guess, that managed to get into

Congress. Perhaps by mistake, but that is something that has always seemed very logical, even though there was sort of a political

prejudice against it. The global or geophysical research letters estimated in 1997 that if the Earth, that is all of the nations, lived up

to the United Nation’s Kyoto protocol on global warming, that we

would prevent no more than 0.1 to 6 degrees Fahrenheit of warming in 50 years. That says that you are talking about some pretty

strong actions that are going to have to be taken. I think this

makes fixing Social Security look easy by comparison. And I guess

I am wondering, you talk about the fact that we have got the highest level of CO2 in 650,000 years. I guess my question is, how was

it that Greenland was harvesting corn in the year, what, 900 or

1000 if the CO2 was so high? Or was there something else making

the world warm? And is it so bad if it gets warmer?

Speaker PELOSI. Well, that is a very good question. About 19 or

18 years ago, early in my term in Congress, I had a piece of legislation that was called the International Banking Environmental Protection Act, and it goes right to your final question. That was a bill

that said—that talked about the International Bank, the World

Bank, the Interamerican Bank, the Asian—all of the multi-development banks. It was a piece of legislation that I introduced on the

Banking Committee. And at the time, I had opposition from my fellow Democrats on the legislation because it called for an environmental impact statement to be made on any projects that the

United States would vote on and that the results of that impact

statement would be made known to the indigenous people of the region as well as internationally. So that is the bottom line of it.

At the very same time—now this had to be—President Bush was

President, so it was after President Reagan, so it was, say, 1990,

something like that. At that time, the President of the World Bank

said, a very distinguished gentleman, but this is what he said. He

said, ‘‘What difference does it make if there is global warming, if

there is climate change? We can just go develop those countries

where the snow—those areas where the snow is melting.’’ It wasn’t

25

really a very informed statement, and that was, again, like 1990,

and it did more to pass my bill than anything I could do, even getting past the Democrats on the Committee who were not particularly well inclined, and President Bush signed it into law.

Mr. AKIN. I guess——

Speaker PELOSI. But there was a reality at the time, and there

are serious consequences to global warming, and we have to face

that reality.

Chairman GORDON. The gentleman’s time is up. I would——

Mr. AKIN. Thank you, Mr. Chairman.

Chairman GORDON.—suggest that it may not matter to Missouri

about global warming, but if Greenland loses all of its ice and

snow, then our friends around the coast are going to be concerned

about it, because there will be an enormous amount of flooding. I

recognize——

Mr. HALL. Mr. Chairman, would you yield?

Chairman GORDON. Yes, Mr. Hall.

Mr. HALL. I think what you are really saying is if we really want

to alter the warming trend significantly, we are going to have to

cut emissions by a very large amount, even beyond Kyoto. And the

question is, that I think the gentleman is asking down there, is do

we currently have affordable technologies for significantly reducing

greenhouse gas emissions, and is there any estimate of cost, and

who pays? I think that is the major question. That is the reason

the gentleman from——

Speaker PELOSI. That is a good answer.

Chairman GORDON. That is a good——

Mr. HALL. The U.S. Chamber did not want to come on such short

notice.

Chairman GORDON. Well, I have a high regard for the Chamber

and their intelligence and their ability, and I think that they could

have made a good statement, but you have raised a good question.

The good news is we have a panel of scientists that just got

through working on a report with 113 nations, I think 6,000 scientists, approved by this country and this President, and we are

going to hear from them with those very specific answers, and I am

glad we are going to be able to do that.

Mr. Costello.

QUESTION AND ANSWER SESSION: CONGRESSIONAL

CUSTOMS

Mr. COSTELLO. Mr. Chairman, thank you.

Mr. Chairman, I do not have any questions for the distinguished

Speaker, but let me say that I am very disappointed and very surprised that we have not extended to this witness, to the Speaker

of the House, the same courtesy that we have extended to many

Members of the House of Representatives since I have served on

this committee.

I have served on the Science Committee for 18 years. As I recall

under the leadership, I think the record will reflect, under the distinguished Chairman Sherry Boehlert, under Mr. Sensenbrenner,

under every Chairman of this committee since I have been there

serving on this committee, I can recall many Members of Congress

testifying, presenting their statement before this committee, and

26

we extended the courtesy to them because of demanding schedules,

let alone the Speaker of the House of Representatives, allowed

them to submit their testimony and to leave without going through

the long ordeal of questions.

I serve on the Transportation and Infrastructure Committee, as

Mr. Boehlert did in his service in the Congress. We extended the

same courtesy there to countless Members of Congress, and I just

have to tell you that I am extremely surprised. This is the first,

but it won’t be the last time that we are going to debate this issue

in this committee and a whole host of other committees. So I just

have to tell you, I am very disappointed and very surprised.

Mr. ROHRABACHER. Would the gentleman yield?

Mr. COSTELLO. We are—I will in just one second. That we are

subjecting the Speaker of the House of Representatives to a higher

standard than we have extended the courtesy to other Members.

Again, I——

Mr. ROHRABACHER. Would the gentleman yield?

Mr. COSTELLO. Yes, I will.

Mr. ROHRABACHER. I agree with you.

Speaker PELOSI. Thank you, Dana.

Chairman GORDON. Well, the good news is that we have a great

Speaker who can handle herself very well.

Speaker PELOSI. I do have to leave.

Chairman GORDON.We have to reset our timer, and so as we do

that, I am going to recess this committee.

Speaker PELOSI. And may I just—may I thank you, Mr. Chairman?

Chairman GORDON. Yes, you may.

Speaker PELOSI. May I thank the distinguished Chairman and

Ranking Member, Members of the Committee. It is the first committee that I have testified before as Speaker of the House. And

because you are a committee about the future, I think that is perfectly appropriate. I wish you much success in your deliberations.

Thank you, Mr. Chairman.

Chairman GORDON. You made this a better hearing. Thank you.

Speaker PELOSI. Thank you.

Chairman GORDON. And we are in recess.

[Recess.]

Chairman GORDON. Thank you all. We have our clocks working

again. And now that we have our equipment back in shape, we will

recommence. And I will call this committee back to order, and I

would like to call our panel of witnesses to the table. Thank you.

We are very pleased to have this distinguished panel of climate

scientists here for this morning. All of our four witnesses have just

returned from Paris where they have participated in the preparation of the Summary for Policy-makers release by the IPCC last

Friday.

I will begin by introducing Mr. Richard Alley. Mr. Alley is a Professor of geosciences and an associate of Earth and Environmental

Systems Institute at the Pennsylvania State University. Mr. Alley

is an expert in the area of glaciers and ice sheets and their potential to cause changes in the sea level. He serves on the National

Academy of Sciences’ Polar Research Board and chaired the NAS

Panel on Abrupt Climate Change. Mr. Alley was a Lead Author of

27

Chapter 4 of the IPCC Report dealing with changes in snow, ice,

and frozen ground.

I will now yield to Representative Udall, if Mr. Udall is here, yes,

to introduce the remaining three panelists who are members and

constituents from his district.

Mr. Udall.

Mr. UDALL. Thank you, Mr. Chairman. And many of you on the

Committee know that Boulder is home to many outstanding climate science facilities, including NOAA’s Earth System Research

Laboratory and the National Center for Atmospheric Research.

And I want to start with Dr. Susan Solomon. She serves as the

Co-Chair of Working Group I of the IPCC, and she provided overall

coordination for the report. Dr. Solomon received her Ph.D. in

chemistry from the University of California at Berkeley in 1981

and currently is a senior scientist at NOAA’s Earth System Research Laboratory. A couple of interesting background facts about

Dr. Solomon, she has a glacier named after her in the Antarctic because of her work on the causes of the ozone hole. She is a member

of the National Academy of Sciences. And in March of 2000, she received the National Medal of Science, the United States’ highest

scientific honor, for her ‘‘Key on Insights in Explaining the Cause

of the Antarctic Ozone Hole.’’ She has also written a book, which

is of great interest to me as an aging mountaineer, called ‘‘The

Coldest March,’’ which covers the tragic story of Captain Robert

Falcon Scott and his British team, who in November 1911, began

a trek across the snows of the Antarctic, striving to be the first to

reach the South Pole. And Dr. Solomon, I can’t help but wonder if

the lessons learned from Scott’s and Amundsen’s expeditions to the

South Pole could be applied to this similarly long, challenging, and

crucial journey to stabilize and reduce greenhouse gases.

Next to Dr. Solomon is Dr. Kevin Trenberth. Dr. Trenberth

served as a Coordinating Lead Author for Chapter 3 of the report,

‘‘Observations, Surface, and Atmospheric Climate Change.’’ Currently, he is the head of the climate analysis section at the National Center for Atmospheric Research (NCAR), originally from

New Zealand, who obtained his doctorate in meteorology in 1972

from MIT. He was named a fellow of the American Meteorological

Society in 1985 and the American Association for the Advancement

of Science in 1994. He has published over 400 scientific articles or

papers, including 40 books or book chapters and over 175 referee

journal articles, and he is listed among the top 20 authors in Hyatt

citations and all of geophysics. He has also recently served as a

member of the National Oceanic and Atmospheric Administration

Climate Working Group from 1987 to 2006 and is a member of

NOAA’s Climate Observing System Council and NOAA’s Advisory

Panel for Climate Change Data and Detection.

At the end of the table is Dr. Gerald Meehl. Dr. Meehl is the Coordinating Lead Author for Chapter 10 of the report, ‘‘Global Climate Projections.’’ Dr. Meehl received his Ph.D. in climate dynamics from the University of Colorado in 1987. His expertise is in the

field of climate modeling. He has been a scientist on staff at NCAR

since 1979. Dr. Meehl has long been involved with the IPCC, having been a member of the Working Group I Report group since

1989 and has participated in the development of several IPCC asVerDate 11-MAY-2000 16:09 May 12, 2008 Jkt 032966 PO 00000 Frm 00039 Fmt 6633 Sfmt 6601 C:\WORKD\FULL07\020807\32966.TXT SCIENCE1 PsN: SCIENCE1
28

sessment reports. He is the author of more than 140 scientific papers and peer-review journals. He has also, since 1979, as a scientist in the Climate and Global Dynamics Division, studied the

interactions between El Nin ̃ o, the Southern Oscillation, and the Indian monsoon, analyzed the results from global-coupled ocean atmosphere general circulation models at NCAR, and examined the

possible effects of increased carbon dioxide, sulfate, aerosols, and

other forcings on global climate.

We are really proud to have you three here today. Thank you for

taking your valuable time to share your conclusions and your observations.

Thank you, Mr. Chairman.

Chairman GORDON. Thank you, Mr. Udall.

This is a very, very distinguished panel, and we know this has

been a hectic period for you, and we do appreciate you being here.

Each of you will be allowed five minutes, but in the spirit of our

former Chairman, I don’t know whether he was embarrassed and

left, but Sherry Boehlert was here earlier, he would say to witnesses of your nature that 300 seconds is not very much to talk

about these very serious problems, so we hope you will be quick,

because we want to have questions, but we want you to take the

time that you need to make the points that need to be.

So Dr. Solomon, please begin.

Panel II:

STATEMENT OF DR. SUSAN SOLOMON, CO-CHAIR, IPCC, WORKING GROUP I: THE PHYSICAL BASIS OF CLIMATE CHANGE;

SENIOR SCIENTIST, EARTH SYSTEM RESEARCH LABORATORY, OFFICE OF OCEANIC AND ATMOSPHERIC RESEARCH,

NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION,

U.S. DEPARTMENT OF COMMERCE

Dr. SOLOMON. Thank you. I would like to thank Chairperson

Gordon, Ranking Member Hall, and the other Members of the

Committee for the opportunity to talk with you today on the Working Group I Report of the IPCC. I appreciate very much the generous introduction by Mr. Udall. I would just like to add that I

have served as an author on various reports of the IPCC beginning

in 1992.

In 2002, I was greatly honored to be formally nominated by the

United States of America to Co-Chair the Fourth Assessment of

Working Group I, the part that deals with physical climate science.

The IPCC was established under the World Meteorological Organization and the United Nations Environment Program to provide

regular assessments for policy-makers on the scientific, technical,

and socio-economic aspects of climate change. Today, we will be

talking about the scientific aspects of climate change, the physical

science basis. IPCC does not do, nor does it manage, research. It

provides assessment reports covering the state of scientific understanding based upon the scientific literature. Each report is written

by international experts on a volunteer basis. IPCC’s past reports

have been highly praised by many organizations, such as scientific

academies around the world, including our own U.S. National

Academy of Sciences.

29

The 152 primary authors of the Working Group I’s Fourth Assessment Report come from every inhabited continent in the world.

About 75 percent of those authors did not work on the Third Assessment Report, the last previous report, guaranteeing a fresh

look. About a quarter of the authors are young, in the professional

sense, having had their highest degree for less than 10 years at the

time that we started our work. Over 600 experts participated in

two rounds of open review. And in addition to the experts, dozens

of governments also provided formal coordinated reviews, including

our own government. In total, the Working Group I scientific assessment received over 30,000 comments. To put those numbers in

perspective, a typical research paper published in a scientific journal is subject to review by two or three experts. It may receive a

few dozen comments. A distinguished team of 27 review editors,

who are independent of the author teams, played an oversight role,

ensuring that all substantive review comments were given appropriate consideration. It took over two years to write, review, revise

and finalize the document, giving us a product that we believe is

unique in many ways; not least the fact that it is not the view of

any one scientist or a few scientists but rather reflects an extremely broad-ranging synthesis of scientific viewpoints. It indicates what is known, and also what is not known, and remaining

uncertainties.

A different Working Group covers impacts and adaptation and

another covers mitigation and policy options. The reports of these

other two groups will be delivered later this spring.

And now I would like to briefly turn to some key highlights of

our own Report, the key messages of this document.

Greenhouse gases have increased markedly since 1750 and are

now at levels unprecedented in many thousands of years. The

warming is unequivocal. Our planet is warming. That is evident in

many different types of observations. Most of the warming of the

past 50 years is very likely due to greenhouse gas increases. We

believe that has a 9-out-of-10 chance based on a very careful detailed assessment that accounts for solar and volcanic effects, that

takes into account many factors, including the simple fact that the

recent years have been remarkably warm, and the chances of that

happening at random are quite small.

We are already committed to further warming. Even if we were

to stabilize all greenhouse gases now, instead of having continuing

increases. And in that regard, the rate of increase of carbon dioxide

of the past 10 years was the largest since direct measurements

began in 1960.

Continued emissions at or above current rates will very likely

lead to larger changes in the 21st century than those of the 20th.

The effects expected include: more heavy rain, more drought, more

heat waves, and more sea level rise. How much depends on how

much we choose to emit on a global basis.

Sea level rise is expected to increase due to expansion of water

in a warmer world. Changes in ice sheets are currently contributing about 12 percent to the total sea level rise of the past decade.

That could grow or it could decrease in the future. And I will leave

it to Dr. Alley to talk more about that.

30

And thank you very, very much for the invitation and for your

attention.

[The prepared statement of Dr. Solomon follows:]

PREPARED STATEMENT OF SUSAN SOLOMON

I thank Chairperson Gordon, Ranking Member Hall, and the other Members of

the Committee for the opportunity to speak with you today on the Working Group

I report of the Intergovernmental Panel on Climate Change 2007 Report (IPCC,

2007). My name is Susan Solomon and I am a Senior Scientist at NOAA’s Earth

System Research Laboratory in Boulder, Colorado. I’ve been a scientist at NOAA for

more than 26 years. Much of my work over that time has focused on understanding

the cause of ozone depletion. In 2000, I received this nation’s highest scientific

award, the National Medal of Science, in recognition of that work. I’ve also been

honored with membership in the U.S. National Academy of Sciences and I am a foreign associate of the French Academy of Sciences and the Acadamiae Europaea. In

addition to my research on ozone depletion, I also do personal research on climate

change, in particular on the range of chemicals that contribute to climate change.

I’m the author or co-author of more than 150 scientific publications, and I’ve served

as an author on various reports of the Intergovernmental Panel on Climate Change

beginning in 1992.

In 2002, I had the honor of being formally nominated by the United States of

America to co-chair Working Group I, the part of the IPCC that deals with physical

climate science. I was selected by the IPCC Panel of governments to serve in that

role, and for almost the past five years have accordingly co-chaired the process that

resulted in the 2007 Working Group I Assessment Report, together with Dr. Qin

Dahe of China. We are assisted by six able vice-chairs from around the world and

by a technical support unit that provides logistical and related functions.

The Intergovernmental Panel on Climate Change was established under the auspices of the World Meteorological Organization and the United Nations Environment Program to provide regular assessments for policy-makers of the scientific,

technical and socio-economic aspects climate change. IPCC does not do or manage

research. It provides assessment reports covering the state of scientific understanding based upon the scientific literature. Each report is written by international

experts on a volunteer basis. IPCC has produced its major assessments every five

to six years since 1990, and the 2007 report is the fourth in that series. The Working Group Co-Chairs and Vice-Chairs select authors on the basis of their scientific

publications and products from among nominees proposed by governments, with due

regard for geographic balance. IPCC’s reports have been highly praised by many organizations such as scientific academies around the world including our own U.S.

National Academy of Sciences.

The 152 authors of the Working Group I Fourth Assessment Report hail from

every inhabited continent in the world. About 75 percent of these authors did not

work on the previous 2001 report. About a quarter of the authors are young in the

professional sense, having had their highest degree for less than 10 years at the

time we began our work. Over 400 other scientists have served as contributing authors. Over 600 experts participated in two rounds of open review. In addition to

the experts, dozens of governments also provided formal coordinated reviews. In

total, the Working Group I assessment received over 30,000 comments. To put these

numbers in perspective, a typical research paper published in a scientific journal is

subject to review by two or three experts. It may receive a few dozen comments.

A distinguished team of 27 review editors, who are independent of the author

teams, played an oversight role ensuring that all substantive review comments were

given appropriate consideration. It took over two years to write, review, revise and

finalize the document. The product is unique in many ways, not least the fact that

it is not the view of any one scientist or a few scientists but rather reflects an extremely broad-ranging synthesis of scientific viewpoints.

A different Working Group (Working Group II), covers impacts and adaptation

and another (Working Group III) covers mitigation and policy options. The reports

of these other two groups are due to be released later this spring. There will also

be a Synthesis Report released in November, 2007, which endeavors to provide a

synthesis of all three Working Group reports.

The Summary for Policy-makers of the Working Group I was approved by the governments of the IPCC Panel in Paris last week. That document is appended here

as the scientific basis of my testimony.

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

BIOGRAPHY FOR SUSAN SOLOMON

Susan Solomon is widely recognized as one of the leaders in the field of atmospheric science. Since receiving her Ph.D. degree in chemistry from the University

of California at Berkeley in l98l, she has been employed by the National Oceanic

and Atmospheric Administration as a research scientist. Her scientific papers have

provided not only key measurements but also theoretical understanding regarding

ozone destruction, especially the role of surface chemistry. In l986 and l987, she

served as the Head Project Scientist of the National Ozone Expedition at McMurdo

Station, Antarctica and made some of the first measurements there that pointed towards chlorofluorocarbons as the cause of the ozone hole. In l994, an Antarctic glacier was named in her honor in recognition of that work. In March of 2000, she received the National Medal of Science, the United States’ highest scientific honor, for

‘‘key insights in explaining the cause of the Antarctic ozone hole.’’ In 2004 she received the prestigious Blue Planet Prize for ‘‘pioneering research identifying the

causative mechanisms producing the Antarctic ozone hole.’’

She is the recipient of many other honors and awards, including the J.B.

MacElwane award of the American Geophysical Union, the Department of Commerce Gold Medal for Exceptional Service, the Henry G. Houghton and Carl-Gustaf

Rossby awards of the American Meteorological Society for excellence in research, the

Arthur S. Flemming Award for exceptional government service, the Common Wealth

Award of the Common Wealth Trust, and the ozone award from the United Nations

Environment Programme. In l992, R&D Magazine honored her as its ‘‘scientist of

the year.’’ She is a recipient of honorary doctoral degrees from Tulane University,

Williams College, the State University of New York at Stony Brook, the Illinois Institute of Technology, the University of Miami, the University of Colorado, and the

University of East Anglia in the UK. She is a member of the U.S. National Academy

of Sciences and a Foreign Associate of both the French Academy of Sciences and

the European Academy of Sciences. Her current research includes climate change

and ozone depletion, and she serves as Co-Chair of Working Group I of the Intergovernmental Panel on Climate Change (IPCC), providing scientific information to the

United Nations Framework Convention on Climate Change.

Chairman GORDON. Thank you, Doctor. And now Dr. Trenberth.

STATEMENT OF DR. KEVIN E. TRENBERTH, COORDINATING

LEAD AUTHOR, IPCC, WORKING GROUP I, CHAPTER 3: OBSERVATIONS: SURFACE AND ATMOSPHERIC CLIMATE

CHANGE; HEAD, CLIMATE ANALYSIS SECTION, NATIONAL

CENTER FOR ATMOSPHERIC RESEARCH

Dr. TRENBERTH. Thank you, Mr. Chairman. I thank Representative Udall for introducing me, and as he said, I am the Coordinating Lead Author of Chapter 3 of the IPCC Report, which Susan

has introduced, and that deals with the observations in the atmosphere and at the surface and also does a synthesis across all observations, and that is what I am going to focus on here.

And essentially, what we have done in the IPCC, perhaps as a

medical analogy, is to do a diagnosis of the vital signs of the planet

Earth. And what we have found, then, is that the planet is running

a fever, so to speak, and the prognosis is that it is apt to become

much worse.

Now to paraphrase the Report, ‘‘Warming of the climate system

is unequivocal.’’ That is actually a quote, and it is very likely due

to human activities.

In my written testimony, a summary is given of the main findings for Chapter 3, and it is linked to the other observational chapters. And the overall summary statement of one of the highlight

points in the policy-maker’s summary is, to quote, ‘‘Warming of the

climate system is unequivocal, as is now evident from observations

of increases in global-averaged air and ocean temperatures, widespread melting of snow and ice, and rising global mean sea level.’’

47

And then there is another item, which goes on to elaborate on more

regional aspects and other variables as well. And that is what I am

going to focus on in my following remarks.

And so we say that the warming of the climate system is unequivocal because it is now clear from an increasing body of evidence showing discernable, physically-consistent changes. In other

words, we can relate all of these changes to warming. And there

are many more variables listed than in the brief IPCC statement.

Now these include, firstly, global average air temperature, and I

am going to come back to that.

If I could have the first slide, if I might, please.

This just shows you global warming is unequivocal, and what I

have done here is to put the main bullets that I am going to talk

about on here, the different variables and the items.

And so as well as global surface air temperature, there are the

air temperatures above the surface, and this refers to what is

called often the satellite temperatures. Sea surface temperatures

are also increasing, and they are very important for things like

storms over the oceans and hurricanes. Subsurface ocean water

temperatures are increasing, below the surface. We can measure

those, and that leads to expansion of the ocean, contributing to sea

level. There is widespread melting of snow in the Northern Hemisphere. There are decreases in Arctic sea ice extent and thickness.

There are decreases in glacier and small ice cap extent and mass.

And as a result, there is a global mean sea level rise at a rate in

the last 12 years of more than a foot a century, and that is contributed to by the expansion of the ocean and the melting of land ice.

The observed surface warming at both global and continental

scales is also consistent with the reduced duration of freeze seaVerDate 11-MAY-2000 16:09 May 12, 2008 Jkt 032966 PO 00000 Frm 00059 Fmt 6633 Sfmt 6601 C:\WORKD\FULL07\020807\32966.TXT SCIENCE1 PsN: SCIENCE1
48

sons, less frost, increases in heat waves, and increased atmospheric

water vapor in the atmosphere, and this is very important, because

it feeds into heavier precipitation events, and this includes, ironically, perhaps, heavier snowfall events, because the atmosphere

can hold more water vapor when it is warmer.

There are also changes in precipitation around the world, and

part of that leads to increases in drought, especially in the tropics,

and this is already evident in the observational record. Increases

in the intensity of hurricane activity are also evident, and there are

changes in the large-scale patterns of atmospheric winds, changes

in where storms are actually going in middle latitudes.

So if I can look at the second—or the next slide, here it is here.

This is the global average temperatures, the time series from

1850 up until 2006. The dots are the annual values. The heavy

blue curve is the decadal smooth values, and the yellow is the sort

of uncertainty around that. And what we frequently do with a

curve like this is to put a straight line through it. And if we do

that, you get this line here for the last 150 years, and on the bottom right, I don’t know if you can see the numbers here, there is

actually—the rate of change is given. And what we can also do is

then put a line through it for the last 100 years, and it looks like

this. And you can see that it is considerably steeper. And then for

the last 50 years, it looks like this. And then for the last 25 years,

it looks like this. And listed at the top there is a list of the last

12 years. Indeed, 11 out of the last 12 years are the warmest on

record.

And so the rate of warming has increased over time, and indeed,

this is the direction we are going in the immediate future.

49

1 Any opinions, findings, conclusions, or recommendations expressed in this publication are

those of the author and do not necessarily reflect those of the National Science Foundation. 2The National Center for Atmospheric Research (NCAR) is sponsored by the National Science

Foundation.

And so the Fourth Assessment Report of IPCC finds that the

Earth is warming and that the major components of the Earth’s climate system are already responding to that warming.

Now the wide variety of observations gives a very high degree of

confidence in the overall findings, and moreover, these changes are

now simulated in climate models for the past 100 years to a reasonable degree, as my colleague Jerry Meehl is likely to talk about,

and this adds confidence to the future projections.

Mr. Chairman, one interpretation of this is that, you know, as

with a fiscal budget, we are running a deficit and building a debt

for the future generations. And our current generation is now running what we might refer to as an environmental deficit, and it

will, indeed, be paid for by the future generations.

I appreciate the opportunity to address the Committee concerning the science of global climate change, and I look forward to

answering any questions.

Thank you.

[The prepared statement of Dr. Trenberth follows:]

PREPARED STATEMENT OF KEVIN E. TRENBERTH

Observations of climate change:

The 2007 IPCC Assessment

Summary

Following a detailed diagnosis of the vital signs of the planet Earth, it has become

evident that the planet is running a ‘‘fever’’ and the prognosis is that it is apt to

get much worse. ‘‘Warming of the climate system is unequivocal’’ and it is

‘‘very likely’’ due to human activities. This is the verdict of the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC), known as

AR4. In the following, I provide a brief introduction to the IPCC and its processes.

A summary is then given of the main findings from the AR4 for Chapter 3, ‘‘Observations: Surface and Atmospheric Climate Change,’’ and its links to other observational chapters. Warming of the climate system is unequivocal as is now clear from

an increasing body of evidence showing discernible physically consistent changes.

These include increases in global average air temperature; atmospheric temperatures above the surface, surface and sub-surface ocean water temperature; widespread melting of snow; decreases in Arctic sea-ice extent and thickness; decreases

in glacier and small ice cap extent and mass; and rising global mean sea level. The

observed surface warming at global and continental scales is also consistent with

reduced duration of freeze seasons; increased heat waves; increased atmospheric

water vapor content and heavier precipitation events; changes in patterns of precipitation; increased drought; increases in intensity of hurricane activity, and changes

in atmospheric winds. That is, the IPCC Fourth Assessment finds that the Earth

is warming, and that major components of the Earth’s climate system are already

responding to that warming. This wide variety of observations gives a very high degree of confidence to the overall findings. Moreover these changes are now simulated

in climate models for the past 100 years to a reasonable degree, adding confidence

to future projections. The summary is followed by a few personal remarks about the

meaning of these findings.

Introduction

My name is Kevin Trenberth.1 I am a senior scientist and the Head of the Climate Analysis Section at NCAR, the National Center for Atmospheric Research.2 I

have authored over 400 publications in the area of climate, and given hundreds of

talks on the subject. I am among the most highly cited researchers in all of geophysics. I am especially interested in global-scale climate dynamics; the observaVerDate 11-MAY-2000 16:09 May 12, 2008 Jkt 032966 PO 00000 Frm 00061 Fmt 6633 Sfmt 6621 C:\WORKD\FULL07\020807\32966.TXT SCIENCE1 PsN: SCIENCE1
50

tions, processes and modeling of climate changes from inter-annual to centennial

time scales. I have particular expertise in El Nin ̃ o, the hydrological and energy cycles, and hurricanes and climate change. I have served on many national and international committees including National Research Council/National Academy of

Science committees, panels and/or boards. I co-chaired the international Climate

Variability and Predictability (CLIVAR) Scientific Steering Group of the World Climate Research Programme (WCRP) from 1996 to 1999 and I have served as a member and officer of the Joint Scientific Committee that oversees the WCRP as a whole

from 1998 to 2006. I chair the WCRP Observations and Assimilation Panel. I have

been involved in global warming science and I have been extensively involved in the

Intergovernmental Panel on Climate Change (IPCC) scientific assessment activity

as a Lead Author of individual chapters, the Technical Summary, and Summary for

Policy-makers (SPM) of Working Group (WG) I for both the Second and Third Assessment Reports (SAR and TAR; IPCC 1996, 2001). I am a Coordinating Lead Author of Chapter 3 of the Fourth IPCC Assessment (AR4) that deals with observations of the surface and atmospheric climate change.

The IPCC is a body of scientists from around the world convened by the United

Nations jointly under the United Nations Environment Programme (UNEP) and the

World Meteorological Organization (WMO) and initiated in 1988. Its mandate is to

provide policy-makers with an objective assessment of the scientific and technical

information available about climate change, its environmental and socio-economic

impacts, and possible response options. The IPCC reports on the science of global

climate and the effects of human activities on climate in particular. Major assessments were made in 1990, 1995, 2001, and now 2007. Each new IPCC report reviews all the published literature over the previous five to seven years, and assesses

the state of knowledge, while trying to reconcile disparate claims and resolve discrepancies, and document uncertainties.

WG I deals with how the climate has changed and the possible causes. It considers how the climate system responds to various agents of change and our ability

to model the processes involved as well as the performance of the whole system. It

further seeks to attribute recent changes to the possible various causes, including

the human influences, and thus it goes on to make projections for the future. WG

II deals with impacts of climate change, vulnerability, and options for adaptation

to such changes, and WG III deals with options for mitigating and slowing the climate change, including possible policy options. Each WG is made up of participants

from the United Nations countries, and for the 2007 assessment there are over 450

Lead Authors, 800 contributing authors, and over 2,500 reviewers from over 130

countries. In my chapter, as well as the two Coordinating Lead Authors, we have

10 Lead Authors, 66 contributing authors, about 100 pages of text, 126 figure panels

in 47 figures, and 863 references. The IPCC process is very open. Two major reviews

were carried out in producing the report, and climate ‘‘skeptics’’ can and do participate, some as authors. For our chapter we received over 2230 comments on the expert review and 1270 on the governmental review, all of which were responded to

in writing and by changing the report. The process is overseen by two Review Editors. The strength is that it is a consensus report. The SPM was approved line by

line by governments in a major meeting in Paris from 29 January to 1 February,

2007. The rationale is that the scientists determine what can be said, but the governments help determine how it can best be said. Negotiations occur over wording

to ensure accuracy, balance, clarity of message, and relevance to understanding and

policy. The latest report (IPCC 2007) reaffirms in much stronger language that the

climate is changing in ways that cannot be accounted for by natural variability and

that ‘‘global warming’’ is happening.

Observed Climate Change

The iconic summary statement of the observations section of the IPCC (2007) report is ‘‘Warming of the climate system is unequivocal, as is now evident

from observations of increases in global average air and ocean temperatures, widespread melting of snow and ice, and rising global mean sea

level.’’ The language here is carefully chosen to reinforce the view that

1) There are multiple lines of evidence from many variables

2) There is a wide body of evidence and multiple analyses of each variable

3) The variables and evidence are physically consistent with warming

4) The human signal has clearly emerged from noise of natural variability, i.e.,

it is large.

Since the TAR, progress in understanding how the current climate is changing in

space and in time has been gained through improvements and extensions of numerVerDate 11-MAY-2000 16:09 May 12, 2008 Jkt 032966 PO 00000 Frm 00062 Fmt 6633 Sfmt 6621 C:\WORKD\FULL07\020807\32966.TXT SCIENCE1 PsN: SCIENCE1
51

ous data sets and data analyses, broader geographical coverage, better understanding of uncertainties, and a wider variety of measurements. Increasingly comprehensive observations are available for glaciers and snow cover since the 1960s,

and for sea level and ice sheets since about the past decade. Numerous changes in

climate have been observed at the scales of continents or ocean basins. These include wind patterns, precipitation, ocean salinity, sea ice, ice sheets, and aspects of

extreme weather.

a. Temperature and related

Instrumental observations over the past 157 years show that temperatures at the

surface (Fig. 1) have risen globally, with important regional variations. For the global average, warming in the last century has occurred in two phases, from the 1910s

to the 1940s (0.35°C or 0.63°F), and more strongly from the 1970s to the present

(0.55°C or 1.0°F) at a rate of about 0.16°C (0.3°F) per decade. An increasing rate of

warming has taken place over the last 25 years, and 11 of the 12 warmest years

on record have occurred in the past 12 years. Indeed, the six years since the TAR

are among the seven warmest years on record. The total warming since the 1800s

is about 0.76°C (1.4°F). Globally, 2006 ranks sixth and it was the warmest on record

in the United States. Sea surface temperatures (SSTs) are also increasing, however

land areas are warming much faster than the oceans since 1970.

Two possible issues with the surface temperature record—urban heat island effects, and discrepancies with balloon-based and satellite measurements—have been

extensively studied in the 2007 IPCC report. The urban heat island effects are real

but local, and have been found to have a negligible influence on the overall surface

temperature record. New analyses of balloon-borne and satellite measurements of

lower- and mid-tropospheric temperature show warming rates that are similar to

the surface temperature record and consistent within their respective uncertainties,

largely reconciling a discrepancy noted in the TAR. The 2007 IPCC report essentially removes these two issues as serious sources of uncertainty for the global surface temperature record.

Regional temperature observations do not always track the global average warming because of atmospheric wave patterns, as well as increased natural variability

at smaller geographic scales. For example, the eastern half of the United States has

not warmed as much as other areas, especially during the daytime, owing to increases in cloud and precipitation associated with changes in atmospheric circulation as the climate changes. On the other hand, average Arctic temperatures increased at almost twice the global average rate in the past 100 years and also since

1960. However, Arctic temperatures have high decadal variability and a warm period was observed from 1925 to 1945, but that was focused in the North Atlantic

and not global as in the recent warming.

52

Since 1950, the number of heat waves globally has increased and widespread increases have occurred in the numbers of warm nights. Cold days, cold nights and

frost have generally become rarer.

Decreases are found in the length of the freeze season of river and lake ice. Temperature at the top of the permafrost layer has increased by up to 3°C since the

1980s in the Arctic. The maximum area covered by seasonally frozen ground has

decreased by about seven percent in the Northern Hemisphere since 1900 and this

value is up to 15 percent in spring.

The average temperature of global ocean water from the surface to a depth of

700m increased significantly from 1961 to 2003, indicating that the ocean is absorbing most of the heat being added to the climate system. This causes seawater to

expand and is estimated to have contributed 0.42mm per year to the average sea

level rise from 1961 to 2003, and 1.8mm per year from 1993 to 2003.

Sea-ice extents have decreased in the Arctic since 1978, particularly in spring and

summer (7.4 percent per decade), and patterns of the changes are consistent with

regions showing a temperature increase, although changes in winds are also a major

factor. Sea-ice extents were at record low values in 2005, which was also the warmest year since records began in 1850 for the Arctic north of 65 N. There have also

been decreases in sea-ice thickness. In contrast to the Arctic, Antarctic sea ice does

not exhibit any significant trend since the end of the 1970s, which is consistent with

the lack of trend in surface temperature south of 65 S over that period. However,

along the Antarctic Peninsula, where significant warming has occurred, progressive

break up of ice shelves has occurred beginning in the late 1980s, culminating in the

break up of the Larsen-B ice shelf in 2002.

The observed surface temperature increases are consistent with the observed

nearly worldwide reduction in glacier and small ice cap mass and extent in the 20th

century. In addition, flow speed has recently increased for some Greenland and Antarctic outlet glaciers, which drain ice from the interior, and melting of Greenland

has increased after about 2000. Glaciers and ice caps respond not only to temperatures but also to changes in precipitation, and both winter accumulation and summer melting have increased over the last half century in association with temperature increases. In some regions moderately increased accumulation observed in recent decades is consistent with changes in atmospheric circulation and associated

increases in winter precipitation (e.g., southwestern Norway, parts of coastal Alaska, Patagonia, and the South Island of New Zealand) even though increased ablation has led to marked declines in mass balances in Alaska and Patagonia. Tropical

glacier changes are synchronous with higher latitude ones and all have shown declines in recent decades. Decreases in glaciers and ice caps contributed to sea level

rise by 0.5mm per year from 1961 to 2003 and 0.8mm per year from 1993 to 2003.

Taken together, shrinkage of the ice sheets of Greenland and Antarctica has contributed 0.4mm per year to sea level rise over 1993 to 2003.

Global average sea level rose at an average rate of 1.8mm per year over 1961 to

2003. The rate was faster during 1993–2003, when truly global values have been

measured from altimeters in space, at about 3.1mm per year. Hence about 60 percent of this is from ocean warming and expansion, and 40 percent is from melting

land ice, adding to the ocean volume. The observation of consistent sea level rise

over several decades, and also an increasing rate of sea level rise in the last decade

or so, is probably the single best metric of the cumulative global warming that we

have experienced to date. There is really no explanation other than global warming

for the observed sea level rise.

The average atmospheric water vapor content has increased over land and ocean

as well as in the upper troposphere, and over the global oceans this is estimated

to be four percent since 1970. The increase is broadly consistent with the extra

water that warmer air can hold and amounts to a fairly constant relative humidity.

The added water vapor also adds to the greenhouse effect and roughly doubles that

due to carbon dioxide, providing a powerful positive feedback to climate change.

The observed surface warming at global and continental scales is consistent with

observed changes in sub-surface ocean water temperature; decreases in sea-ice extent and thickness; decreases in glacier and small ice cap extent and mass; sea-level

rise; reduced duration of freeze seasons, increased heat waves; and increased atmospheric water vapor content. That is, the IPCC Fourth Assessment finds that the

Earth is warming, and that major components of the Earth’s climate system are already responding to that warming. This wide variety of observations gives a very

high degree of confidence to the overall findings.

b. Precipitation and related

The 2007 IPCC report finds that changes are occurring in the amount, intensity,

frequency, and type of precipitation in ways that are also consistent with a warming

53

planet. These aspects of precipitation generally exhibit large natural variability

(compared to temperature trends), and El Nin ̃ o and changes in atmospheric circulation patterns have a substantial influence, making it harder to detect trends in the

observational record.

A key ingredient in changes in character of precipitation is the observed increase

in water vapor and thus the supply of atmospheric moisture to all storms, increasing the intensity of precipitation events. Indeed, widespread increases in heavy precipitation events and risk of flooding have been observed, even in places where total

amounts have decreased. Hence the frequency of heavy rain events has increased

in most places but so too has episodic heavy snowfall events that are thus associated

with warming. Snow cover has decreased in many Northern Hemisphere regions,

particularly in spring, and more precipitation is falling as rain instead of snow.

These changes are consistent with changes in permafrost, noted above.

Long-term trends from 1900 to 2005 have been observed in total precipitation

amounts over many large regions. Significantly increased precipitation has been observed in eastern parts of North and South America, northern Europe and northern

and central Asia. Drying has been observed in the Sahel, the Mediterranean, southern Africa and parts of southern Asia. Precipitation is highly variable spatially and

temporally. Robust long-term trends have not been observed for other large regions.

The pattern of precipitation change is one of increases generally at higher northern

latitudes (because as the atmosphere warms it holds more moisture) and drying in

the tropics and subtropics over land. Basin-scale changes in ocean salinity provide

further evidence of changes in the Earth’s water cycle, with freshening at high latitudes and increased salinity in the subtropics.

More intense and longer droughts have been observed over wider areas since the

1970s, particularly in the tropics and subtropics. Increased drying due to higher

temperatures and decreased precipitation have contributed to these changes, with

the latter the dominant factor. The regions where droughts have occurred are determined largely by changes in sea surface temperature (SST), especially in the tropics

(such as during El Nin ̃ o), through changes in the atmospheric circulation and precipitation. In the western United States, diminishing snow pack and subsequent

summer soil moisture reductions have also been a factor. In Australia and Europe,

direct links to warming have been inferred through the extreme nature of high temperatures and heat waves accompanying drought.

Satellite records suggest a global trend towards more intense and longer lasting

tropical cyclones (including hurricanes and typhoons) since about 1970, correlated

with observed warming of tropical SSTs. There is no clear trend in the annual number of tropical cyclones globally although a substantial increase has occurred in the

North Atlantic after 1994. There are concerns about the quality of tropical cyclone

data, particularly before the satellite era. Further, strong multi-decadal variability

is observed and complicates detection of long-term trends in tropical cyclone activity.

c. Synthesis across variables

In summary, global mean temperatures have increased since the 19th century, especially since the mid-1970s. Temperatures have increased nearly everywhere over

land, and SSTs have also increased, reinforcing the evidence from land. However,

global warming does not mean that temperatures increase steadily or uniformly, indeed temperatures have increased neither monotonically, nor in a spatially uniform

manner, especially over shorter time intervals. The atmospheric circulation has also

changed: in particular increasing westerly wind flow is observed in most seasons in

both hemispheres. In the Northern Hemisphere this brought milder maritime air

into Europe and much of high-latitude Asia from the North Atlantic in winter, enhancing warming there. In the Southern Hemisphere, where the ozone hole has

played a role, it has resulted in cooling over 1971–2000 for parts of the interior of

Antarctica but large warming in the Antarctic Peninsula region and Patagonia.

Temperatures generally have risen more than average where flow has become more

poleward, and less than average or even cooled where flow has become more

equatorward, reflecting atmospheric patterns of variability.

Over land in low latitudes and in summer more generally, there is a strong tendency for either hot and dry or cool and wet. Hence areas that have become wetter,

such as the eastern United States and Argentina, have not warmed as much as

other land areas. Increased precipitation is associated with increases in cloud and

surface wetness. Thus more heat goes into increased evapotranspiration and less

into raising temperature at the surface in wetter conditions.

The three main ocean basins are unique and contain very different wind systems,

SST patterns and ocean currents, leading to vastly different variability associated,

for instance, with El Nin ̃ o in the Pacific, and the ocean currents including the Gulf

Stream in the Atlantic. Consequently the oceans have not warmed uniformly, espeVerDate 11-MAY-2000 16:09 May 12, 2008 Jkt 032966 PO 00000 Frm 00065 Fmt 6633 Sfmt 6621 C:\WORKD\FULL07\020807\32966.TXT SCIENCE1 PsN: SCIENCE1
54

cially at depth. SSTs in the tropics have warmed at different rates and help drive,

through coupling with tropical convection and winds, distinctive wave patterns

known as teleconnections around the world. This has changed the atmospheric circulation and the monsoons. Changes in precipitation and storm tracks are not as

well documented but clearly respond to these changes on inter-annual and decadal

timescales. When precipitation increases over the ocean, as it has in recent years

in the tropics, it decreases over land, although it has increased over land at higher

latitudes. Droughts have increased over many tropical and mid-latitude land areas,

in part because of decreased precipitation over land since the 1970s but also from

increased drying arising from increased atmospheric demand associated with warming.

Many of these observed changes are now simulated in climate models run for the

past 100 years, adding confidence to understanding of the relationship with the

agents that alter the climate, and human-induced changes in atmospheric composition, in particular, as is documented in other IPCC chapters.

Some implications

The scientific understanding of climate change is now sufficiently clear to show

that specific global and regional changes resulting from global warming are already

upon us. Uncertainties remain, and new efforts at reprocessing past satellite records

for phenomena such as hurricanes are required, but the 2007 IPCC report definitively shows that the climate is changing. ‘‘Warming is unequivocal’’ and it is ‘‘very

likely’’ caused by human activities.

In my personal opinion as a climate scientist, the IPCC report strongly implies

the need for a three pronged approach of mitigation, adaptation, and maintaining

and improving climate observing and information systems.

While there are uncertainties (although these cut both ways) and some changes

arising from global warming may be benign or even beneficial, at least in some

places and in the short run, the IPCC report shows that the rate of change as projected exceeds anything seen in nature in the past 10,000 years. Moreover, the inertia of the climate system and the long life of carbon dioxide in the atmosphere mean

that we are already committed to a significant level of climate change. I believe that

mitigation actions are certainly needed to significantly reduce the build-up of greenhouse gases in the atmosphere and lessen the magnitude and rate of climate

change.

At the same time, the 2007 IPCC report makes clear that even aggressive mitigation would yield benefits many decades in the future, and that no amount of mitigation can avoid significant climate change. I believe it is apt to be disruptive in many

ways. Hence it is also vital to plan to cope with the changes, such as enhanced

droughts, heat waves and wild fires, and stronger downpours and risk of flooding.

Managing water resources will be a major challenge in the future. Adapting to climate change and reducing vulnerability is essential. This means that we should

adapt to climate change by planning for it and making better predictions of likely

outcomes on several time horizons.

Finally, although not reported by the IPCC, my experience in working with observations of climate change has led me to urge the Committee to address the considerable shortcomings in our observing systems. Weather observing systems are continually used for climate purposes for which they were not designed. Moreover, weather stations come and go and changes are made without regard to the effect on the

climate record. Changes in observing systems, especially from satellites, as new satellites and instruments are launched, create artifacts in the climate record. Loss of

Earth observing satellites is also of concern, as documented in the recent National

Research Council (2007) decadal survey. Ground based observations are not being

adequately kept up in many countries. Calibration of climate records is critical.

Small changes over long times are characteristic of climate change but they occur

in the midst of large variations associated with weather and natural climate variations such as El Nin ̃ o. Yet the climate is changing and an imperative is to track

the changes and the causes as they occur. We need to build a system based on these

observations to inform decision-makers on what is happening, and why, and what

the predictions are for the future on several time horizons.

I appreciate the opportunity to address the Committee concerning the science of

global climate change, and look forward to answering any questions you may have

today or in the future.

References and some bibliography

IPCC, 1996: Climate Change 1995: The Science of Climate Change. Eds. J.T. Houghton et al., Cambridge University Press, Cambridge, U.K. 572 pp.

55

IPCC, 2001: Climate Change 2001: The Scientific Basis. Eds. J.T. Houghton, et al.,

Cambridge University Press, Cambridge, U.K. 881 pp.

IPCC, 2007: Climate Change 2007: The Scientific Basis. Eds. S. Solomon, et al.,

Cambridge University Press, Cambridge, U.K. (in press).

Karl, T.R., and K.E. Trenberth, 2003: Modern global climate change. Science, 302,

1719–1723.

Karl, T.R., and K.E. Trenberth, 2006: Modern global climate change. Science Magazine’s State of the Planet, Donald Kennedy and the editors of Science magazine,

Eds., Island Press, 88–98.

National Research Council, 2007: Earth Science and Applications from Space: National Imperatives for the Next Decade and Beyond. The National Academies

Press.

Trenberth, K.E., 2001: Stronger evidence for human influences on climate: The 2001

IPCC Assessment. Environment, 43, 4(May), 8–19.

Trenberth, K.E., T.R. Karl and T.W. Spence, 2002: The need for a systems approach

to climate observations. Bull. Amer. Meteor. Soc., 83, 1593–1602.

Trenberth, K.E., 2005: Uncertainty in hurricanes and global warming. Science, 308,

1753–1754.

Trenberth, K.E., and D.J. Shea, 2006: Atlantic hurricanes and natural variability

in 2005. Geophys. Res. Lett., 33, L12704, doi:10.1029/2006GL026894.

BIOGRAPHY FOR KEVIN E. TRENBERTH

Dr. Kevin Trenberth is Head of the Climate Analysis Section at the National Center for Atmospheric Research (NCAR) in Boulder, CO. From New Zealand, he completed a first class honors degree in mathematics at the University of Canterbury,

Christchurch, New Zealand, and obtained his Sc.D. in meteorology in 1972 from

Massachusetts Institute of Technology, Cambridge, Massachusetts. He was previously employed as a research scientist in the New Zealand Meteorological Service

and was a Professor at the University of Illinois for nearly seven years prior to joining NCAR in 1984.

He was named a Fellow of the American Meteorological Society (AMS) in 1985,

the American Association for Advancement of Science (AAAS) in 1994, the American

Geophysical Union in 2006 and an Honorary Fellow of the New Zealand Royal Society in 1995. In 2000 he received the Jule G. Charney award from the AMS and in

2003 he was given the NCAR Distinguished Achievement Award. He has served as

an editor and associate editor for several professional journals. He edited a 788 page

book, Climate System Modeling (1992). He has published over 400 scientific articles

or papers, including 40 books or book chapters, and over 175 refereed journal articles and has given many invited scientific talks as well as appearing in a number

of television, radio programs and newspaper articles. He is listed among the top 20

authors in highest citations in all of geophysics.

Trenberth has served on a number of national and international advisory committees and panels including many panels, committees and a board of the National

Academy of Sciences. Trenberth has been prominent in the Intergovernmental Panel

on Climate Change (IPCC) Scientific Assessment activities, was a Convening Lead

Author for the 1995 Scientific Assessment and Lead Author for the 2001 assessment

(including for the Technical Summary and Summary for Policy-makers) and is a Coordinating Lead Author of the 2007 assessment. He has recently served as a member of the National Oceanic and Atmospheric Administration (NOAA) Climate

Working Group (from 1987 to 2006), and is a member of NOAA’s Climate Observing

System Council, and NOAA’s Advisory Panel for Climate Change Data and Detection. He also recently served on the Joint Scientific Committee of the World Climate

Research Programme (WCRP) from 1999 to 2006 and was an officer from 2003 to

2006, and he chairs the WCRP Observations and Assimilation Panel. He served on

the Scientific Steering Group for the WCRP Climate Variability and Predictability

(CLIVAR) program and was Co-Chair from 1995 to 1999.

See http://www.cgd.ucar.edu/cas/trenbert.html

Chairman GORDON. Dr. Alley.

56

STATEMENT OF DR. RICHARD B. ALLEY, LEAD AUTHOR, IPCC,

WORKING GROUP I, CHAPTER 4: OBSERVATIONS: CHANGES

IN SNOW, ICE AND FROZEN GROUND; EVAN PUGH PROFESSOR OF GEOSCIENCES AND ASSOCIATE OF THE EARTH

AND ENVIRONMENTAL SYSTEMS INSTITUTE, PENNSYLVANIA

STATE UNIVERSITY

Dr. ALLEY. Thank you, Mr. Chairman, honored Members.

As Dr. Trenberth pointed out, observations of snow and ice show

that melting is now widespread. We see this in snow cover in the

north. We see this in the Arctic sea ice. We see it in most of the

glaciers of the world. We see it in frozen ground and permafrost.

We see it in the great ice sheets of Greenland and Antarctica. And

we see it even where there is more snow falling. And so it is really

hard to blame a loss of ice on loss of snow if there is more snow

in some places, and yet it is melting faster. And so it is very clear

that warming is implicated in this.

I would like to focus especially on the large ice sheets of Greenland and Antarctica, because they have great potential to change

sea level. Snow falls on top, melting happens around the side, especially in Greenland, and our understanding of those processes has

gotten a lot better. However, we have observed surprising changes

in the flow of the ice sheets around their edges that we didn’t really expect.

If I may, for a moment, an ice sheet is just a two-mile-thick, continent-wide pile of snow that has been squeezed to ice under its

own weight. And like any pile, it spreads under its own weight. If

I were to pour pancake batter on a griddle in front of us here, you

would see it spread and thin and drip off the edge. The same thing

happens to an ice sheet. It spreads and thins and it drips icebergs

off of the edge.

If I were to grease that pancake griddle, you would see the batter

spread faster. Ice sheets have exactly the same problem. In Greenland, observations show that when the melt water starts on the

edge, it goes through great holes in the ice to the bottom, and

water makes things slippery. And so the ice actually spreads faster

because of this melt water that amplifies the effects of it. And so

in the same way that you can grease a pancake griddle, the ice

sheet is greasing its own bed to spread faster.

If I were holding the pancake batter in with a spatula and I removed it, of course, the batter would spread faster, and ice sheets

have this same problem, as well. When the ice gets down to the

ocean, it usually does not immediately break off to make an iceberg. It spreads over the ocean in something we call an ice shelf,

and that will run aground on an island, or it will sheer past the

rocky sides of a fjord, and those hold back in the same way that

your spatula holds back the spreading pancake batter.

Now in a warming world, those are very low in elevation. They

can be warmed easily. They are in contact with the ocean already.

They are at the melting point underneath, and so they can melt

very easily underneath. We have seen where warming has attacked

these spatulas, these ice shelves, and when they have been pulled

out of the way, the ice behind is gone faster by as much as eightfold. So we know these things are out there, and we know that we

don’t have a really good scientific understanding of all of these asVerDate 11-MAY-2000 16:09 May 12, 2008 Jkt 032966 PO 00000 Frm 00068 Fmt 6633 Sfmt 6601 C:\WORKD\FULL07\020807\32966.TXT SCIENCE1 PsN: SCIENCE1
57

1 Any opinions, findings, conclusions, or recommendations expressed in this publication are

those of the author and do not necessarily reflect those of the Pennsylvania State University,

the Intergovernmental Panel on Climate Change, or other organizations.

pects. And when we look to the future, we expect sea level to rise,

as ocean water warms and expands, as the mountain glaciers melt,

and with effects from changing snowfall and melting on the big ice

sheets.

And there is a greatly increased confidence in that. If you compare the projections of sea level rise that were just now made in

the new Report to those that were made in the previous report, we

have a better understanding of certain things. The numbers have

looked slightly different. Had we treated uncertainties in exactly

the same way, you would have had very similar projections. They

have not changed much. But we have this additional uncertainty

that we just don’t know whether these changes in the spreading of

that giant pile in Antarctica or that giant pile in Greenland will

slow down, whether they will stay constant, whether they will

speed up. It is just this big uncertainty that is sitting out there.

We do not have any credible scientific models of which I personally am aware that would dump an ice sheet into the ocean over

decades. However, it is possible that we will reach temperatures

over decades that, if sustained, would lose an ice sheet over centuries to millennia. As someone who works for a land grant institution, which tries to provide useful advice to you, I am distressed

that I cannot tell you more accurately what the future might hold.

As someone who gets paid to do research, I am really excited. I am

going to go home and have fun.

So to summarize, we have much scientific confidence that warming-induced ice loss is now widespread in the climate system, that

it is contributing to sea level rise and other changes. Improved understanding of many aspects of this is reflected in the new Report,

and it is really wonderful, but there are unexpected changes in ice

flow that have occurred for which we lack a scientific basis to provide accurate estimates.

Thank you.

[The prepared statement of Dr. Alley follows:]

PREPARED STATEMENT OF RICHARD B. ALLEY

Changes in Ice:

The 2007 IPCC Assessment

Introduction

My name is Richard Alley.1 I am Evan Pugh Professor of Geosciences and Associate of the Earth and Environmental Systems Institute at the Pennsylvania State

University. I have authored over 170 refereed scientific publications in the areas of

ice and climate, which are ‘‘highly cited’’ according to a prominent indexing service,

and I have given hundreds of presentations concerning my areas of expertise. My

research interests focus especially on glaciers and ice sheets, their potential for

causing major changes in sea level, and the climate records they contain. I have

been a member of many national and international committees, including chairing

the National Research Council’s Panel on Abrupt Climate Change and serving on

their Polar Research Board. I have contributed to the efforts of the Intergovernmental Panel on Climate Change (IPCC) in various ways, and serve as a Lead Author on Chapter 4 (the Cryosphere), and on the Technical Summary and the Summary for Policy-makers of Working Group I of the Fourth Assessment Report. A

58

brief description of the IPCC process as it applies to this testimony is appended, for

your information.

Changes in Ice

The newly released report reaffirms the strong scientific evidence that human activities are changing the composition of the planet’s atmosphere, and that this is

warming the climate and affecting it in other ways. In particular, our chapter documents the increasingly strong evidence for widespread reductions in the Earth’s ice,

including snow, river and lake ice, sea ice, permafrost and seasonally frozen ground,

mountain glaciers, and the great ice sheets of Greenland and Antarctica. Our chapter and others highlight the strong evidence for the dominant role of warming,

which is primarily being caused by human activities, in this loss of ice.

I will briefly summarize some of these many aspects, especially focusing my attention on the issue of ice-sheet shrinkage and its possible effect on sea-level rise. I

will rely on the recent IPCC report, as well as other materials as needed.

Snow cover has decreased in most regions, as shown by satellite data tied to limited surface observations. Snow melt is shifting earlier into the spring. Declines in

April 1 snowpack have been measured in 75 percent of western North American

sites monitored. Impacts of climate change on people will be covered in the WGII

report, coming soon, but other sources express great concern about earlier snowmelt

in the U.S. West, because the snow pack in many regions is a dominant source of

summertime water. Trends in snow cover cannot be explained by changing precipitation (and indeed, in some very cold places snow depth has increased with increasing precipitation), but the overall shrinkage of snow cover can be explained by rising

temperature.

Freezing of rivers and lakes generally has been occurring later in the fall, with

thawing earlier in the spring, giving longer intervals of open water. Coordinated

data collection is scarce, however, and the data set not extensive.

Arctic sea ice, formed by freezing of ocean water, has decreased in area and thickness. The change in the summer has been especially large, with ice lost from an

area twice the size of Texas between 1979 and 2005 (decreasing trend in ice area

of seven percent per decade over that interval). Data sets from satellites, tied to observations from ships submarines, have been especially important in documenting

these changes. Although shifts in circulation of the ocean and atmosphere may have

contributed to the ice loss, greenhouse-gas warming is likely to have been important. (Any Antarctic sea-ice changes fall within natural variability; cooling associated with the ozone hole may be affecting Antarctic climate, a complex subject beyond the scope of these brief remarks.)

Permanently frozen ground (permafrost) and seasonally frozen ground are not

readily monitored globally. However, available reports point to overall warming and

thawing of this ice in the ground, in response to rising air temperatures and

changes in snow cover.

Glaciers and ice caps occur primarily in mountainous areas, and near but distinct

from the Greenland and Antarctic ice sheets. On average, the world’s glaciers were

not changing much around 1960 but have lost mass since, generally with faster

mass loss more recently. Glacier melting contributed almost an inch to sea-level rise

during 1961–2003 (about 0.50 mm/year, and a faster rate of 0.88 mm/year during

1993–2003). Glaciers experience numerous intriguing ice-flow processes (surges,

kinematic waves, tidewater instabilities), allowing a single glacier over a short time

to behave in ways that are not controlled by climate. Care is thus required when

interpreting the behavior of a particular iconic glacier (and especially the coldest

tropical glaciers). But, ice-flow processes and regional effects average out if enough

glaciers are studied for a long enough time, allowing glaciers to be quite good indicators of climate change. Furthermore, for a typical mountain glacier, a small warming will increase the mass loss by melting roughly five times more than the increase

in precipitation from the ability of the warmer air to hold more moisture. Thus, glaciers respond primarily to temperature changes during the summer melt season. Indeed, the observed shrinkage of glaciers, contributing to sea-level rise, has occurred

despite a general increase in wintertime snowfall.

Ice-sheet Changes

The large ice sheets of Greenland and Antarctica are of special interest, because

they are so big and thus could affect sea level so much. Melting of all of the world’s

mountain glaciers and small ice caps might raise sea level by about one foot (0.3m),

but melting of the great ice sheets would raise sea level by just over 200 feet (more

than 60m). We do not expect to see melting of most of that ice, but even a relatively

small change in the ice sheets could matter to the world’s coasts.

59

A paper published in the journal Science last week (Rahmstorf et al., 2007) compared the projections made in the 2001 IPCC Third Assessment Report to changes

that have occurred. The carbon dioxide in the atmosphere has followed expectations

closely. Temperature has increased just slightly faster than projected, but well within the stated uncertainties. Sea level is following near the upper edge of the stated

uncertainties, however, well above the central estimate. Changes in the ice sheets

help explain this.

The 2001 IPCC report noted large uncertainties, but presented a central estimate

that the combined response of the ice sheets to warming would be net growth, lowering the sea-level rise from other sources averaged over the 21st century, with increase in snowfall on the ice sheets exceeding increase in melting and with little

change in ice flow. Data collected recently show that the ice sheets very likely have

been shrinking and contributing to sea level rise over 1993–2003 and with even

larger loss by 2005, as noted in the IPCC report and elsewhere (e.g., Alley et al.,

in press; Cazenave, 2006). Thickening in central Greenland from increased snowfall

has been more than offset by increased melting in coastal regions. Many of the fastmoving ice streams that drain Greenland (see the Figure, below) and parts of Antarctica have accelerated, transferring mass to the ocean and further contributing to

sea-level rise. The total contribution to sea-level rise from the ice sheets remains

smaller than the contribution from mountain-glacier melting or from the expansion

of ocean water as it warms. However, the existence of the ice-sheet contribution, its

important ice-flow source, and the large potential sea-level rise from such mechanisms in the future motivate careful consideration.

An ice-sheet is a two-mile-thick, continent-wide pile of snow that has been

squeezed to ice. All piles tend to spread under their own weight, restrained by their

own strength (which is why spilled coffee spreads on a table top but the stronger

table beneath does not spread), by friction beneath (so pancake batter spreads faster

on a greased griddle than on a dry waffle iron), or by ‘‘buttressing’’ from the sides

(so a spatula will slow the spreading of the pancake batter). Observations at a site

in Greenland have shown that meltwater on top of the ice sheet flows through the

ice to the bottom and reduces friction there. More melting in the future thus may

reduce friction further, speeding the production of icebergs and the increase in sea

level.

Some early gothic cathedrals suffered from the ‘‘spreading-pile’’ problem, the sides

tending to bulge out while the roof sagged down, with potentially unpleasant consequences. The beautiful solution was the flying buttress, which transfers some of

the spreading tendency to the strong Earth beyond the cathedral. Ice sheets also

have flying buttresses, called ice shelves. The ice reaching the ocean usually does

not immediately break off to form icebergs, but remains attached to the ice sheet

while spreading over the ocean. The friction of these ice shelves with islands, or

with the sides of embayments, helps restrain the spreading of the ice sheet much

as a flying buttress supports a cathedral. The ice shelves are at the melting point

where they contact water below, and are relatively low in elevation hence warm

above. Ice shelves thus are much more easily affected by climatic warming than are

the thick, cold central regions of ice sheets. Rapid melting or collapse of several ice

shelves has occurred recently, allowing the ‘‘gothic cathedrals’’ behind to spread faster, contributing to sea-level rise.

Although science has succeeded in generating useful understanding and models

of numerous aspects of the climate, similar success is not yet available for ice-sheet

projections, for reasons that I would be happy to explore with the Committee. We

do not expect ice sheets to collapse so rapidly that they could raise sea level by meters over decades; simple arguments point to at least centuries. However, the IPCC

report is quite clear on the lack of scientific knowledge to make confident projections.

Synopsis

In summary, with high scientific confidence, changes are occurring in much of the

world’s ice. These are being caused primarily by warming. That warming is largely

being caused by greenhouse gases being released to the atmosphere by human activities. Shrinkage of the large ice sheets was unexpected to many observers but appears to be occurring, and the poor understanding of these changes prevents reliable

projections of future sea-level rise over long times.

60

Recently published estimates of the mass balance of the Greenland ice

sheet through time (Alley et al., in press)

A Total Mass Balance of 0 indicates neither growth nor shrinkage, and -180 Gt

yr-1 indicates ice-sheet shrinkage contributing to sea-level rise of 0.5 mm/year (one

inch in about 50 years), as indicated. Each box extends from the beginning to the

end of the time interval covered by the estimate, with the upper and lower lines

indicating the uncertainties in the estimates. A given color is associated with a particular technique, and the different letters identify different studies. Two estimates

have arrows attached, because those authors indicated that the change is probably

larger than shown. The dotted box in the upper right is a frequently-cited study that

applies only to the central part of the ice sheet, which is thickening, and misses the

faster thinning in the margins.

References Cited

Alley, R.B., M.K. Spencer and S. Anandakrishnan. Ice-sheet mass balance: Assessment, attribution and prognosis. In press. Annals of Glaciology.

Cazenave, A. 2006. How fast are the ice sheets melting? Science 314, 1250–1252.

Rahmstorf, S., A. Cazenave, J.A. Church, J.E. Hansen, R.F. Keeling, D.E. Parker

and R.C.J. Somerville. 2007. Recent observations compared to projections.

Science, Sciencexpress, 10.1126/science.1136843.

The Intergovernmental Panel on Climate Change (IPCC) Assessment

The IPCC was founded by the United Nations Environment Programme and the

World Meteorological Organization in 1988 (this information is summarized from

the publications of the IPCC, which are widely available including at www.ipcc.ch).

The Panel is charged to assess the best scientific information on climate change, in

a comprehensive, objective, open and transparent way. The panel is divided into

three working groups. Working Group I assesses the scientific aspects of the climate

system and climate change. Working Group II assesses the vulnerability of socioeconomic and natural systems to climate change, negative and positive consequences

of climate change, and options for adapting to it. Working Group III assesses options

for limiting greenhouse gas emissions and otherwise mitigating climate change.

The IPCC reports are written by teams of authors, who are nominated by governments and international organizations. Author selection is based on expertise relative to the specific task. Experts come from universities, research centers, business

and environmental associations, and other organizations from more than 130 countries. Procedures are enforced to ensure that the results of the IPCC process are

policy-relevant. A rigorous review process is used throughout the process. Specialists

61

review a first draft of the report, and governments, authors and independent experts review a second draft, with special review editors for each chapter ensuring

that balance is maintained and that all review comments are properly addressed.

For our chapter, Chapter 4 (the Cryosphere) of Working Group I of the Fourth Assessment Report, which in near-final draft had 47 pages, 255 references, and 23 figures involving 41 panels, the two Coordinating Lead Authors, nine Lead Authors

(informed by 44 contributing authors), and two review editors addressed over 1,000

comments from the expert review alone. As one of the shorter chapters, we were

not the busiest. The Third Assessment Report in total involves more than 2,500 expert reviewers, 800 contributing authors, and 450 Lead Authors.

The report from Working Group I was condensed into a Technical Summary, and

then into a Summary for Policy-makers. The Summary for Policy-makers was approved line-by-line by governments in plenary from January 29 to February 1 in

Paris, and was released to the public on February 2, 2007. The Technical Summary

and the full report will follow later in the spring, as will reports from Working

Groups II and III. The approximately 1,000-page main report from Working Group

I is being copy-edited and formatted for publication, with a limited number of small

changes in specific wording for clarity based on the results of the Paris plenary.

BIOGRAPHY FOR RICHARD B. ALLEY

Dr. Richard Alley is Evan Pugh Professor of Geosciences and Associate of the

Earth and Environmental Systems Institute at The Pennsylvania State University,

University Park, where he has worked since 1988. He was graduated with the Ph.D.

in 1987 from the University of Wisconsin–Madison and with M.Sc. (1983) and B.Sc.

(1980) degrees from The Ohio State University–Columbus, all in Geology. Dr. Alley

teaches, and conducts research on the climatic records, flow behavior, and sedimentary deposits of large ice sheets, to aid in prediction of future changes in climate

and sea level. His experience includes three field seasons in Antarctica, eight in

Greenland, and three in Alaska. His awards include the Seligman Crystal of the

International Glaciological Society, the first Agassiz Medal of the European Geosciences Union Cryospheric Section, a Presidential Young Investigator Award, the

Horton Award of the American Geophysical Union Hydrology Section and Fellowship in the Union, the Wilson Teaching Award and the Mitchell Innovative Teaching

Award of the College of Earth and Mineral Sciences and the Faculty Scholar Medal

in Science at Penn State. Dr. Alley has served on a variety of advisory panels and

steering committees, including chairing the National Research Council’s Panel on

Abrupt Climate Change, and has provided requested advice to numerous government officials in multiple administrations including a U.S. Vice President, the President’s Science Advisor, and a Senate Committee. He has published over 170 refereed

papers, and is a ‘‘highly cited’’ scientist as indexed by ISI. His popular account of

climate change and ice cores, The Two-Mile Time Machine, was chosen science book

of the year by Phi Beta Kappa in 2001. Dr. Alley is happily married with two children, two cats, and two bicycles, and resides in State College, PA, where he coaches

recreational soccer and occasionally plays some.

Chairman GORDON. Thank you, Dr. Alley.

I just received a message here that the International House of

Pancakes wanted to offer you an evening job if you need to supplement. I know that land grant institutions don’t pay that well.

Dr. Meehl.

STATEMENT OF DR. GERALD A. MEEHL, COORDINATING LEAD

AUTHOR, IPCC, WORKING GROUP I, CHAPTER 10: GLOBAL

CLIMATE PROJECTIONS; SENIOR SCIENTIST, NATIONAL

CENTER FOR ATMOSPHERIC RESEARCH

Dr. MEEHL. Yes. Dr. Alley’s enthusiasm is, indeed, contagious. I

think we would all like to run back to our labs and get back to

work on science after doing a lot of this kind of assessment work.

But I want to thank the Chairman and Members of the Committee for the opportunity to communicate to you some of the findings from the IPCC AR4.

The thing I wanted to stress, the first thing, is that a significant

new aspect regarding projections of future climate change has inVerDate 11-MAY-2000 16:09 May 12, 2008 Jkt 032966 PO 00000 Frm 00073 Fmt 6633 Sfmt 6601 C:\WORKD\FULL07\020807\32966.TXT SCIENCE1 PsN: SCIENCE1
62

volved an unprecedented coordinated international effort to perform a set of climate change experiments. These were done with

high-end computer climate modeling tools we use to quantify possible future climate change. These are called Global-Coupled Ocean

and Atmosphere Climate Models, or we just call them AOGCMs for

short, and a total of 16 modeling groups from around the world

from 11 countries, and this includes three groups in the United

States, use 23 of these high-end models, AOGCMs, to perform coordinated climate-change experiments. These include simulations

of 20th century climate with both natural and anthropogenic

forcings, three possible outcomes for the 21st century based on low,

medium, and high emission scenarios and three idealized stabilization experiments.

These data were then collected and made openly available for

analysis, and this is really the first time we have been able to do

something on this scale. And to date, over 950 scientists from

around the world have accessed these model data. And the many

papers that have been written were assessed by us in the process

of coming up with the AR4. These analyses provide an improved

quantification of likelihoods and many aspects of future climate

change.

And a little more on the models, the amount of detail and realism in the climate models we use has increased in recent years.

This is partly because of our increase in understanding of the processes in the climate system and also in part because the calculations provided by newer supercomputers has increased.

For future climate, this now allows us to provide more detailed

information on aspects of the climate system, such as possible future changes of weather and climate extremes.

Regarding near-term climate change, warming of about twotenths of a degree centigrade per decade over the next couple of

decades is projected across the range of scenarios considered. And

this actually continues about the same rate we have observed in

observations over the past few decades.

Hypothetically, if concentrations of greenhouse gases had been

held constant at year 2000 values, we are already committed to

about a tenth of a degree C per decade, mainly due to the slow response of the ocean. By the 2020s, most of the United States is projected to warm by about an additional one degree centigrade, and

this is larger than warming we observed during the 20th century

and very likely larger than estimates of natural variability during

the 20th century.

As we approach the middle part of the 21st century and beyond,

it is clear that it makes a difference regarding what emission scenario we choose to follow now. By 2100, there is a spread of globally-averaged surface air temperature increase among the six scenarios considered. Best estimates for this global warming range

from about 1.8 degrees centigrade for the lowest scenario with a

likely range of 1.1 to 2.9 degrees C and four degrees C for the highest scenario with a likely range of 2.4 degrees to 6.4 degrees centigrade.

Now these scenarios are constructed based on various assumptions of future population growth, economic activity, and energy

usage, but no climate initiatives were considered in these scenarios.

63

So based on the existing models available for assessment, the

central values for projection of sea level rise by 2100 are similar

to previous estimates. These range from about 20 to 40 centimeters, depending on scenario, with the upper end of the range for

the highest scenario of about 60 centimeters. These ranges of sea

level rise are narrower than previous estimates, mainly because of

reduced uncertainties in some of the components that contribute to

sea level rise.

However, a large unquantified uncertainty arises from processes

we don’t yet fully understand and have only recently been able to

observe, such as potential ice sheet instability that Dr. Alley was

alluding to.

For example, additional sea level rise from this source by the end

of the 21st century could add another 10 to 20 centimeters to the

upper ranges and higher future sea level rise values cannot be excluded. This is an area of great concern and active ongoing research given the potential consequences.

As seen in recent trends and observations, the future pattern for

temperature change is characterized by greater warming over land

compared to oceans and more warming at high northern latitudes.

Associated with these temperature changes there are projected decreases of snow cover, decreases in thaw depth over most permafrost regions and other changes. Reductions in sea ice, of course,

go along with increased temperatures with a late summer sea ice

free Arctic by the end of the 21st century in the high forcing scenario in some models. The pattern of future precipitation change

indicates increases at higher latitudes, such as the northern tier of

states during winter and decreases over subtropical land areas,

such as the Southwest United States.

Though the picture of a future warming world appears bleak, it

is not yet hopeless. The six different mission scenarios considered

in the AR4 show that the longer we wait to do something, the

worse the problem gets. These scenarios also illustrate that what

we do now can make a difference for the future.

Thank you very much for your invitation to address the Committee.

[The prepared statement of Dr. Meehl follows:]

PREPARED STATEMENT OF GERALD A. MEEHL

Global Climate Projections:

The 2007 IPCC Assessment

Introduction

I thank the Chairman and other Members of the Committee for the opportunity

to communicate to you today some of the recent findings from the IPCC Fourth Assessment Report (AR4). My name is Gerald Meehl, Senior Scientist at the National

Center for Atmospheric Research (NCAR) in Boulder, Colorado. My research interests include tropical climate involving the monsoons and El Nin ̃ o Southern Oscillation, climate variability and climate change. I have authored or co-authored more

than 145 peer-reviewed scientific journal articles and book chapters. I have been involved with the Intergovernmental Panel on Climate Change (IPCC) assessments

since the first one that was published in 1990. I was a Contributing Author on that

first assessment and its update in 1992, a Lead Author for the 1995 Assessment,

and a Coordinating Lead Author for the 2001 and the present 2007 assessments.

I have been involved with committees of the World Climate Research Program

(WCRP) on Climate Variability and Predictability (CLIVAR), and am currently CoVerDate 11-MAY-2000 16:09 May 12, 2008 Jkt 032966 PO 00000 Frm 00075 Fmt 6633 Sfmt 6621 C:\WORKD\FULL07\020807\32966.TXT SCIENCE1 PsN: SCIENCE1
64

Chair of the WCRP/CLIVAR Working Group on Coupled Models (WGCM). This committee organized and coordinated the international modeling groups in performing

climate model experiments for assessment in the AR4, and in the collection and

analysis of data from those model experiments. Through the efforts of that committee, this extensive multi-model data set on climate change has been made openly

available for analysis, and over 950 scientists from around the world have been able

to access and analyze these data. The resulting papers have contributed extensively

to the IPCC AR4. I have served on several National Research Council (NRC) panels,

and am currently a member of the NRC Climate Research Committee. I was a Lead

Author on the U.S. Climate Change Science Program (CCSP) Report 1.1 on temperature trends in the atmosphere, and am currently co-coordinator for the CCSP

report on weather and climate extremes in a changing climate.

In my capacity as a Coordinating Lead Author for the chapter on climate change

projections for the IPCC AR4, I was in Paris last week attending the Plenary of the

IPCC where the IPCC Fourth Assessment Report was accepted and approved by the

roughly 180 governments that make up the IPCC. Thus, the IPCC is a group of governments, not a group of scientists, which is a common misconception. The IPCC

commissions assessments to be performed roughly every five or six years, and they

are prepared through the efforts of hundreds of scientists from around the world

who are actively involved in state-of-the-art research in climate science. The IPCC

assessments provide a comprehensive view of the current state of human understanding of climate science and climate change. My testimony today will summarize

some of the main findings of the IPCC AR4 with regards to projections of future

climate change.

A much larger group of climate models have contributed to the IPCC AR4

A major international effort to perform a set of coordinated climate change experiments was organized by the WCRP/CLIVAR WGCM. A total of 16 modeling groups

from 11 countries (three groups from the U.S.) used 23 global coupled climate models to perform these coordinated climate change experiments that involved simulations of the 20th century climate, three possible outcomes for the 21st century

(based on low, medium and high emission scenarios), and three idealized stabilization experiments. In addition there were idealized carbon dioxide increase experiments, and associated stabilization experiments with doubled and quadrupled CO2

amounts. These data were then collected, and over 31 Terabytes of model data were

archived at the DOE-sponsored Program for Climate Model Diagnosis and Intercomparison (PCMDI) at Lawrence Livermore National Lab (LLNL) in Livermore,

CA. WGCM then coordinated the analysis of this multi-model data set. This unprecedented effort has involved over 950 scientists who have accessed these model data

and wrote many papers that were assessed in the AR4. This massive effort was the

first time the international climate modeling community has performed such an extensive set of climate change experiments, with the output from those experiments

openly available for analysis.

Climate change commitment and near-term warming

Several of the experiments run with the most recent global climate models explored the concept of climate change commitment. That is, if concentrations of

greenhouse gases are stabilized at various levels, how much more warming would

occur due to the emissions already in the system. Such committed climate change

is due to the time lag introduced by the oceans because it takes longer for water

to warm. If concentrations of greenhouse gases could have been stabilized in the

year 2000, a committed warming of about 0.1C per decade averaged over the period

2000 to 2020 would occur, with smaller warming continuing after that. Of course

there are ongoing increases of greenhouse gases, so the models project that no matter what emissions scenario is followed (not taking into account possible large volcanic eruptions that we are not able to forecast but would produce temporary cooling a year or two after the eruption), the combination of climate change commitment

and additional warming from increasing greenhouse gases would result in a warming of about 0.2C per decade over the next two decades.

The sea level rise commitment is much longer-term. This is due to the effects of

thermal expansion on sea level. That is, since water has the physical property of

expanding as it heats up, as the warming penetrates deeper into the ocean, an ever

increasing volume of water expands and contributes to ongoing sea level rise. Since

it would take centuries for the entire volume of the ocean to warm in response to

the effects of the greenhouse gases we have already put into the air, we are committed right now to further sea level rise that would continue for centuries.

Previous IPCC assessments starting in 1990 used global climate models to project

global warming of between about 0.15C and 0.3C per decade for 1990 to 2005. The

65

actual observed values of global warming for that time period are about 0.2C per

decade. This increases our confidence in the climate model projections for future climate change, since previous generations of models were able to project warming

rates similar to those subsequently observed.

Climate change later in the 21st century

As we approach the middle part of the 21st century and beyond, it makes a difference regarding what emissions scenario we choose to follow now. By 2100 there

is a spread of globally averaged surface air temperature increase among the six scenarios considered, with best estimates ranging from nearly 2C for a lowest scenario

(B1) and about 4C for the highest scenario (A1FI). Likely ranges for warming at the

end of the 21st century are also now provided. For example, for a low scenario (B1),

the warming averaged for 2090–99 relative to 1980–99 has a best estimate of 1.8C

with a likely range of 1.1C to 2.9C. For a medium scenario (A1B), the best estimate

is 3.4C with a likely range of 2.0C to 5.4C, and for the highest scenario (A1FI), the

best estimate is 4.0C with a likely range from 2.4C to 6.4C. There are greater values

at the higher end of the ranges due to relatively new understanding regarding the

nature of the feedbacks from the carbon cycle (i.e., how the oceans and land absorb

and emit carbon dioxide). Though only relatively few global coupled climate models

include the complex processes involved with modeling the carbon cycle, this feedback is positive (i.e., adding to more warming) in all models so far considered.

Therefore, the addition of carbon cycle feedbacks provides higher values on the

warm end of the uncertainty ranges.

Rising global temperatures are very likely to raise sea level by expanding ocean

water and melting mountain ice caps and glaciers. Recently observed ice sheet dynamical processes that could produce potentially larger contributions to sea level

rise than accounted for in the present estimates are not fully included in existing

models of the Greenland and Antarctic ice sheets assessed for the AR4. Therefore

larger increases in sea level rise than the present projections cannot be excluded.

Consequently, the AR4 cannot quantify a full uncertainty range of sea level rise at

the end of the 21st century. Based on the existing models available for assessment,

the central values for projections of sea level rise by 2100 are similar to previous

estimates, ranging from about 30 to 40 cm. About 60 percent to 70 percent of this

increase is due to thermal expansion of sea water (i.e., as water warms, it expands)

and is thus connected to the more certain estimates of warming of surface air temperatures. There is less certainty with regards to the other components of sea level

rise (contributions from melting land glaciers and small ice caps, the net balance

between snow accumulation and melting ice for Greenland and Antarctica, and the

dynamic ice flow contributions from Greenland and Antarctica). This is reflected in

the ranges of sea level rise that differ from previous estimates, due in part to the

way the uncertainty of these contributions is taken into account. This is an area

of great concern and active ongoing research given the potential consequences.

The projected globally averaged temperature increase is also reflected by patterns

of regional climate changes. As noted in previous assessments, this pattern for temperature change is characterized by greater warming over land compared to oceans,

and more warming at the high northern latitudes. Associated with these temperature changes, there are projected decreases of snow cover, and increases in thaw

depth over most permafrost regions. Reductions in sea ice go along with the increased temperatures, with a sea-ice free Arctic by the end of the 21st century in

the high forcing scenario in some models. The pattern of future precipitation change

indicates likely increases at higher latitudes, such as the northern tier of states, and

decreases over subtropical land areas such as the Southwest U.S.

It would seem that the relatively small increases in average temperature amounting to a few degrees may not make that much difference. However, such small

changes in average values can lead to much larger changes of extreme weather and

climate events. For example, it is very likely that heat waves will increase in intensity, frequency and duration, with heavy precipitation events also increasing. These

projected changes in extremes continue trends we have already observed.

Though present-day global climate models used for the climate change projections

discussed above have inherent limitations in simulating hurricanes, new types of

specialized models have been formulated to study such possible future changes.

From a range of models, it is likely that future tropical cyclones (typhoons and hurricanes) will become more intense with larger peak wind speeds and more intense

precipitation. This is physically consistent with ongoing increases of sea surface

temperature since there is a well-established link between warmer water and hurricane intensity. There is less confidence in projections of a global decrease in numbers of hurricanes since the model results are not as consistent.

66

There has been some interest in the media and in Hollywood regarding the possibility of an abrupt shutdown of the Atlantic Ocean meridional overturning circulation (MOC). This large-scale ocean circulation system, sometimes called the ‘‘ocean

conveyor belt,’’ transports heat northwards, in part via the Gulf Stream, to the

North Atlantic. A warming of the North Atlantic from increasing greenhouse gases

could produce more precipitation and warmer water that would stabilize this overturning circulation and consequently reduce the amount of northward heat transport. Using this line of reasoning, if the MOC suddenly shut down, there could be

a sudden decrease in northward heat transport and possibly a large cooling of the

North Atlantic region. Research assessed in the IPCC AR4 indicates that it is very

likely that the MOC will indeed slow down during the 21st century. With the weakening of this circulation, there is somewhat less heat transported northward. But

there is still a future net increase of surface air temperatures over the North Atlantic since the warming from the increased greenhouse gases overwhelms any cooling

from the MOC slowdown. Additionally, it is very unlikely that the MOC will undergo a large abrupt shut-down during the 21st century, with an associated cooling

from such a sudden shut-down also very unlikely. No global coupled climate model

simulation assessed in the AR4 produces such an abrupt change, even if Greenland

ice melt is taken into account. However, changes in the MOC in the 22nd century

and beyond cannot be assessed with confidence at this time.

Summary

The IPCC AR4 represents the current state of human understanding of climate

science and climate change. Projected changes of future climate have relied on an

unprecedented set of coordinated climate change experiments undertaken by the

international climate modeling community, and the U.S. modeling groups have

played a prominent role in this process. The projections of future climate are consistent with earlier IPCC assessments in terms of the magnitude of global changes.

This is reassuring since successive generations of climate models are now producing

comparable results from assessment to assessment. But there are now many more

details as well as increased certainty regarding quantifications of regional climate

change, extremes, hurricanes, climate change commitment, ocean circulation

changes, and better information regarding both near-term and longer-term climate

change.

BIOGRAPHY FOR GERALD A. MEEHL

Gerald Meehl received his Bachelor’s (1974), Master’s (1978), and Ph.D. (1987) degrees in climate dynamics from the University of Colorado in Boulder. Since 1973,

he has worked at the National Center for Atmospheric Research (NCAR) in various

capacities, including participating in the Tropical Wind Energetics Reference Level

Experiment (TWERLE) in Pago Pago, American Samoa, and Christchurch, New

Zealand (1975–76), in the Monsoon Experiment (MONEX) in Bintulu, Sarawak, Malaysia, and Kathmandu, Nepal (1978–79), and in the Tropical Ocean Global Atmosphere (TOGA) Coupled Ocean Atmosphere Response Experiment (COARE) in

Townsville, Australia, Kapingamarangi, FSM, Pohnpei, FSM, and Republic of Nauru

(1992–93). Since 1979, as a scientist in the Climate and Global Dynamics Division,

he has studied the interactions between El Nin ̃ o/Southern Oscillation (ENSO) and

the Indian monsoon, analyzed the results from global coupled ocean-atmosphere

general circulation models at NCAR, and examined the possible effects of increased

carbon dioxide, sulfate aerosols, and other forcings on global climate. He is the author of more than 140 scientific papers in peer-reviewed journals, and has contributed chapters to several textbooks. He was a contributing author for the Intergovernmental Panel on Climate Change (IPCC) 1990 and 1992 assessments, a Lead Author for the chapter on climate model projections of future climate change for the

1995 IPCC assessment, a Coordinating Lead Author for the chapter on climate

model projections of future climate change for the IPCC Third Assessment Report

published in 2001, and a Coordinating Lead Author for the chapter on global climate change projections for the 2007 IPCC Fourth Assessment Report. Among his

current committee appointments, he is a member of National Research Council Climate Research Committee, Co-Chair of the Community Climate System Model Climate Change Working Group, Co-Chair of the World Climate Research Programme

CLIVAR Working Group on Coupled Models (WGCM), and Chairman of the WGCM

Climate Simulation Panel which has coordinated analyses of global coupled climate

model simulations for the IPCC Fourth Assessment Report.

67

DISCUSSION

THE IPCC PROCESS

Chairman GORDON. Thank you, Dr. Meehl.

Now, Dr. Solomon, the message I am taking away from this Report is that the climate is changing, the Earth is getting warmer,

human activities have started and continue to drive this change.

Have I gotten that message right?

Dr. SOLOMON. Basically, yes. I would put some ‘‘very likely’’s in

there, but I would agree with you.

Chairman GORDON. Thank you. And Dr. Solomon, I understand

that all 113 nations had to agree on that. This had to be a unanimous Report, is that correct?

Dr. SOLOMON. All of the nations present in Paris, including the

United States, were in agreement with the final document. That is

correct. It was a consensus document.

Chairman GORDON. And by virtue of that, does that mean that

this would be on the conservative side of a report?

Dr. SOLOMON. I would actually say that the point of this kind of

a report is to say what we know, what we don’t know, and what

the remaining uncertainties are. I don’t think that a report, such

as ours, if it is intended to be the sort of global consensus statement that it is could go any farther than we have gone. I think we

have done a very fair job in reporting what is known and what is

not known. I would not call it conservative, personally.

GLACIER MELT ACCELERATIONS

Chairman GORDON. And Dr. Alley, I understand that the research had to be cut off by the end of 2005, and so additional information that came from Greenland with the ice floats and things of

this nature were not a part of this information. Is that correct?

Dr. ALLEY. Some of the information on acceleration in Greenland

did come in time to be assessed properly and a couple of recent papers are not included. That is correct.

Chairman GORDON. And from press reports that I have seen, it

indicated that in terms of the rise in sea level, you were somewhat

limited to the change of temperature. As the water got warmer, obviously, it would expand. How limited were you in the discussions

and the new information concerning Greenland and elsewhere

where glaciers were melting?

Dr. ALLEY. The melting of mountain glaciers, in the Alps, for example, or in the Rockies, is taken account of, and—with improved

accuracy, so I think we understand better. The changes in snowfall

and melting on top of Greenland and on top of Antarctica are also

taken into account and somewhat better than it had been. The——

Chairman GORDON. But was it taken into account in terms of the

rise in the sea level?

Dr. ALLEY. It is taken into account in terms of rise in sea level.

What is missing is an accurate assessment of these changes in the

spreading, the changes in the flow, how much the self-lubrication

of the ice or the loss of the spatulas would contribute to accelerated

flow in a warmer world. And we simply don’t have the scientific

understanding to provide an accurate assessment of that.

68

Chairman GORDON. But we know it is not going to get slower.

It is only going to get faster. The question is just how much faster.

Dr. ALLEY. But we don’t even really know that, because that sort

of implies a knowledge that we are trying rather desperately to

build for you right now. Certainly, we have seen glacier accelerations, and we have seen those accelerations in response to warming. We have fairly high confidence in that. If you see future warming, it, perhaps, would not be surprising that if warming causes

mass loss that more warming would cause more mass loss, but we

are still fighting on that. This document works very, very hard to

be an assessment of what is known scientifically, what is well

founded in the refereed literature, and when we come up to that

cliff and look over and say we don’t have a foundation right now,

we have to tell you that. And on this particular issue, the trend of

acceleration of this flow with warming, we don’t have a good assessed scientific foundation right now.

Chairman GORDON. How long would you expect that that would

be before you will?

Dr. ALLEY. I don’t know. I am very optimistic that we will be better in five years. I am doubtful that we will have as good an understanding of that as we do of, say, mean global surface temperature

that Dr. Meehl was talking about.

Chairman GORDON. Thank you, Dr. Alley.

Mr. Rohrabacher.

Mr. ROHRABACHER. Thank you very much, and thank you very

much, Dr. Alley, for your honesty and your candor, considering that

people obviously wanted you to say something else than what you

have just told us, that they would like to have certainty. For the

record, Mr. Chairman, I would like to put in the record a list of

a number of scientists and statements by scientists, very well respected statements and very well respected scientists, who are not

part of this so-called consensus that any climate change is being

caused by human activity. If I could submit those for the record at

this point.

Chairman GORDON. Certainly, Mr. Rohrabacher, and I will also

point out that the Minority had the opportunity to call any of these

witnesses and have them be part of this panel——

Mr. ROHRABACHER. I appreciate that——

Chairman GORDON.—and had quite a bit of time to be able to do

that. But certainly this will add to our report. And without any objection, they will be made a part of the record.

[The information follows:]

INFORMATION TO BE PLACED IN THE RECORD RELATING TO THE HOUSE SCIENCE &

TECHNOLOGY COMMITTEE HEARING ON THE STATE OF CLIMATE CHANGE SCIENCE

2007 ON FEBRUARY 8, 2007 BY CONGRESSMAN DANA ROHRABACHER

Timothy Ball

‘‘Believe it or not, Global Warming is not due to human contribution of Carbon

Dioxide (CO2). This in fact is the greatest deception in the history of science. We

are wasting time, energy and trillions of dollars while creating unnecessary fear and

consternation over an issue with no scientific justification.’’

Monday, February 5, 2007

Open News web site

http://www.opednews.com/articles/opedne¥daniel¥g¥070207¥global¥warming¥

3a¥the¥.htm

69

Dr. Tim Ball, Chairman of the Natural Resources Stewardship Project

(www.nrsp.com), is a Victoria-based environmental consultant and former climatology Professor at the University of Winnipeg. He can be reached at: letters@canadafreepress.com

Fred Singer

‘‘Crucially, greenhouse models cannot explain the observed patterns of warming—

temperature trends at different latitudes and altitudes. These data, published in a

U.S. Government scientific report in May 2006, lead us to conclude that the human

contribution is not significant. Most of current warming must therefore stem from

natural causes. It may well be part of an unstoppable solar-driven 1,500-year cycle

of warming and cooling that’s been documented in ice cores, ocean sediments, stalagmites, and so forth—going back a million years.

‘‘If indeed most of current warming is natural rather than from greenhouse gases,

there is little point in reducing carbon dioxide emissions. Further, carbon dioxide

is not an atmospheric pollutant. Programs and policies for carbon dioxide control

should therefore be scrapped—including uneconomic alternative energy sources, carbon-sequestration efforts, and costly emission-trading schemes. All of these waste

money and squander scarce resources, without in any way affecting the atmosphere

or climate. Humans have adapted to major climate changes in the past, and we

should have no problem doing so in the future.’’

The Science and Environmental Policy Project’s The Week That Was newsletter

(2/3/07)

http://www.sepp.org/Archive/weekwas/2007/February%203.htm

S. Fred Singer, an atmospheric physicist, is Professor Emeritus of environmental

sciences at the University of Virginia, adjunct scholar at the National Center for

Policy Analysis, and former Director of the U.S. Weather Satellite Service. He is

also a research fellow at the Independent Institute and author of Hot Talk, Cold

Science: Global Warming’s Unfinished Debate (The Independent Institute, 1997).

Bill Gray

‘‘I think we’re coming out of the little ice age, and warming is due to changes to

ocean circulation patterns due to salinity variations.’’

Quote from an article in the Daily Reporter-Herald (9/19/06)

Dr. William M. Gray is a world famous hurricane expert and Emeritus Professor

of Atmospheric Science, Colorado State University.

From an interview with Dr. William M. Gray in Discover Magazine, September

2005, Title: ‘‘Weather Seer: ‘We’re Lucky’ ’’

A few years ago, you almost called it quits because you’d lost so much funding. What made you continue?

G: I don’t have the budget that I had, so I have to cut back my project way back.

I am in retirement. I’m still working everyday, but I don’t teach and don’t have as

many graduate students and as much financial need. I’ve got a little money from

Lexington Insurance out of Boston, and I have some National Science Foundation

money. For years haven’t had any NOAA, NASA, or Navy money. But I’m having

more fun. Right now I’m trying to work on this human-induced global warming

thing that I think is grossly exaggerated.

You don’t believe global warming is causing climate change?

G: No. If it is, it is causing such a small part that is negligible. I’m not disputing

that there has been global warming. There was a lot of global warming in the 1930’s

and ’40s, and then there was a slight global cooling from the middle ’40s to the early

’70s. And there has been warming since the middle ’70s, especially in the last 10

years. But this is natural, due to ocean circulation changes and other factors. It is

not human induced.

That must be a controversial position among hurricane researchers.

G: Nearly all of my colleagues who have been around 40 or 50 years are skeptical

as hell about this whole global warming thing. But no one asks us. If you don’t

know anything about how the atmosphere functions, you will of course say, ‘‘Look,

greenhouse gases are going up, the globe is warming, they must be related.’’ Well,

just because there are two associations, changing with the same sign, doesn’t mean

that one is causing the other.

70

With last year’s hurricane season so active, and this year’s looking like it

will be, won’t people say it’s evidence of global warming?

G: The Atlantic has had more of these storms in the least 10 years or so, but in

other ocean basins, activity is slightly down. Why would that be so if this is climate

change? The Atlantic is a special basin? The number of major storms in the Atlantic

also went way down from the middle 1960s to the middle ’90s, when greenhouse

gases were going up.

Why is there scientific support for the idea?

G: So many people have a vested interest in this global warming thing. . .all these

big labs and research and stuff. The idea is to frighten the public, to get money to

study it more. Now that the cold war is over, we have to generate a common enemy

to support science, and what better common enemy for the glove than greenhouse

gases?

Are your funding problems due in part to your views?

G: I can’t be sure, but I think that’s a lot of the reason. I have been around 50

years, so my views on this are well known. I had NOAA money for 30 some years,

and then when the Clinton Administration came in and Gore started directing some

of the environmental stuff, I was cut off. I couldn’t get any NOAA money. They

turned down 13 straight proposals from me.

GLOBAL WARMING TRENDS

Mr. ROHRABACHER. Thank you.

My question—well, first of all, Dr. Solomon, is a glacier named

after you?

Dr. SOLOMON. Yeah, I am afraid so.

Mr. ROHRABACHER. Is it melting? I am serious about that. Is the

glacier named after you melting?

Dr. SOLOMON. Well, that particular one is at 78 degrees south,

sir. It is at such a high latitude in the Antarctic that——

Mr. ROHRABACHER. So it is not melting?

Dr. SOLOMON.—it is out of reach of global warming.

Mr. ROHRABACHER. It is out—it is not melting. Thank you very

much.

Let me—I am not a scientist. Look, I am a former journalist and

a writer, and so I have to really, you know, look down and see what

is being said, condense things into the real meaning. Let me ask

you just a couple fundamental questions.

I saw on the History Channel a whole big special on the mini ice

age. Was there a mini ice age, and did it end at about the middle

of the 19th century? Or you know, were there really Vikings that

were living at a much higher temperature on Greenland 1,000

years ago, or are we being—is the History Channel just telling us,

you know, a myth?

Dr. TRENBERTH. Mr. Rohrabacher, if I can have a crack at that.

There was a period called the little ice age——

Mr. ROHRABACHER. Okay.

Dr. TRENBERTH.—that, indeed, occurred around about that time

up until about the end of, say, the 19th century, which was——

Mr. ROHRABACHER. All right.

Dr. TRENBERTH.—clearly cooler. It is a little bit of a Eurocentric

view of the world, though, because a lot of it was certainly focused

in the North Atlantic European region where, you know——

Mr. ROHRABACHER. Well, that, of course, is where we had all of

the statistics being kept, and so at that time period, of course it

would be Eurocentric, because they didn’t keep all of those temVerDate 11-MAY-2000 16:09 May 12, 2008 Jkt 032966 PO 00000 Frm 00082 Fmt 6633 Sfmt 6601 C:\WORKD\FULL07\020807\32966.TXT SCIENCE1 PsN: SCIENCE1
71

perature records in other places in the world. So there was a mini

ice age, and it went down to about the middle of the 19th century.

I couldn’t help but notice that the chart that was presented started

the low point of this mini ice age. It started there to prove that

there was a global warming trend.

Now if you start at the bottom of something that is recognized

as a time of cooling on the Earth, isn’t it going to go up naturally

if there is a natural cycle going on?

Dr. TRENBERTH. The instrumental record, we have been able to

push it back to 1850, and that is the reason it starts then. And the

way we would characterize it is that there is really not much

change up until about 1920. There is a warming that goes on from

about 1920 to 1940, and we believe that some of that—the work

that the models have done and the instruments and what has happened with the sun is that a part of that is natural and associated

with changes in the sun. It is really only in the last 35 years, since

about 1970, that the global warming aspect has clearly emerged

above these levels of natural variability. So——

Mr. ROHRABACHER. And we are only talking about one degree, a

one degree change, right? And in fact, over these last 20 years, you

are talking about it is less than one degree, because your one degree started back in the middle of the 19th century.

Dr. TRENBERTH. Well, one degree Celsius. Over one degree Fahrenheit since 1970.

Mr. ROHRABACHER. Okay. One degree since 1970. Now is it possible that there is a natural cycle going on here? Is that a possibility?

Dr. TRENBERTH. This is one of the things that we can do now.

Natural cycles also have causes. They—you know, they come from

somewhere.

Mr. ROHRABACHER. Like sunspots.

Dr. TRENBERTH. Sunspots or——

Mr. ROHRABACHER. Okay.

Dr. TRENBERTH.—changes in the heat of the ocean or——

Mr. ROHRABACHER. I have only got a little bit of time left. Let

me ask you—I am sorry, because you know, we are only given a

very short period of time to ask. What percentage of what are

called greenhouse gases are created by nature or—and that is even

leaving the sunspot issue out, as compared to humankind? All of

humankind produces what, 10 percent of the greenhouse gases, five

percent?

Dr. SOLOMON. Well, this is in my area of research, Mr. Rohrabacher, so I would like to respond. On the issue of solar activity,

we have direct measurements in how the sun has varied since

1970. They show very clearly that the solar, in radians, changes

since 1970 have been very small, much less than the changes in

the energy budget due to greenhouse gases. You will find that figure to——

Mr. ROHRABACHER. Okay. So the greenhouse gases are what percentage again?

Dr. SOLOMON. Well, greenhouse gas contribution to warming far

outstrips the solar brightness changes. That is a figure——

Mr. ROHRABACHER. Okay. But what percentage of

greenhouse——

72

Dr. SOLOMON. May I continue——

Mr. ROHRABACHER. No, no, because I have only got a little bit of

time. I am sorry——

Dr. SOLOMON.—because you have asked——

Mr. ROHRABACHER.—I control this time. You don’t. I am asking

what percentage of the greenhouse gases are created by human

beings?

Dr. SOLOMON. Yeah. That is what I was just about to get to——

Mr. ROHRABACHER. Okay.

Dr. SOLOMON.—actually. Thank you. If you look at Figure 1 of

our Summary for Policy-makers, it actually shows you the time series of carbon dioxide, for example, and you will see it has increased markedly since 1750——

Mr. ROHRABACHER. I am not asking about that.

Dr. SOLOMON. It is almost entirely due to human activities.

Mr. ROHRABACHER. Listen. Listen. Hold on. Excuse me. But unless you are going to be honest about this, we are not going to have

an honest discussion. At least Mr. Alley was being honest about it,

saying we don’t know. If I ask you a direct question, what percentage of the greenhouse gases are caused naturally rather than by

human beings, can’t anybody answer that directly?

Dr. SOLOMON. The CO2 increase is caused almost entirely——

Mr. ROHRABACHER. I didn’t ask that.

Dr. SOLOMON.—by human beings.

Mr. ROHRABACHER. I didn’t—listen. I am asking you a direct

question, what percentage of the greenhouse gases are made by

human beings and what percentage are made by nature?

Dr. SOLOMON. I would say a fair number regarding the increase

since 1750 is that greater than 90 percent of the increase has been

caused by human activities.

Mr. ROHRABACHER. That wasn’t the question, was it? Why can’t

you—listen, this is very dishonest. You are supposed to be a scientist. I have asked you a direct question. Can anybody else in the

panel be honest about the answer?

Dr. SOLOMON. Sir, I am really trying to be honest.

Mr. ROHRABACHER. What percentage of the greenhouse gases in

our atmosphere and created in our atmosphere are being created

by nature versus humankind? I have asked you that four times

now and have been dodged four times.

Dr. SOLOMON. No, sir, I am not dodging your question. I am

sorry.

Mr. ROHRABACHER. Does someone else—I didn’t say the increase.

Dr. SOLOMON. There is a baseline.

Mr. ROHRABACHER. I didn’t say increase.

Dr. SOLOMON. There is, indeed, a baseline.

Mr. ROHRABACHER. What is the baseline?

Dr. SOLOMON. The baseline for carbon dioxide is 270 parts per

million. What we are now at is about 380 parts per million.

Mr. ROHRABACHER. Excuse me, I am asking—Mr. Chairman——

Dr. SOLOMON. That increase is due to human activity.

Mr. ROHRABACHER. Mr. Chairman, I don’t—I would like my time

not to be spent by witnesses not——

Dr. SOLOMON. 270 out of 380. I can——

73

Chairman GORDON. Well, your time has been up for quite some

time.

Mr. ROHRABACHER. Well, I wish we could have this—is everyone

else afraid to answer that question as well?

Mr. BAIRD. Would the gentleman from California yield for one

second?

Mr. ROHRABACHER. Sure.

Mr. BAIRD. My belief is that the answer resides in what the

gentlelady just said in the following sense. If you take a baseline,

one might presume that the baseline is the natural prevalence of

CO2, because——

Mr. ROHRABACHER. That is not my question.

Mr. BAIRD. No, I understand that, but I am going to get to your

question——

Mr. ROHRABACHER. I have been trying to get an honest——

Mr. BAIRD. Stay with me. I am going to get to your—I am going

to get to it.

Mr. ROHRABACHER. All right.

Mr. BAIRD. And then if you look at where we are now——

Mr. ROHRABACHER. Yes.

Mr. BAIRD.—that difference between baseline and where we are

now would presumably yield the information you are asking for,

which is what percentage of the carbon is caused by——

Mr. ROHRABACHER. No, no, no. That is not the suggestion at all—

I mean, that is not the way. I mean, it is a simple question, and

every scientist that I have asked has said it is less than 10 percent

of any of the greenhouse gases are caused by human activity. And

I was just trying to find out whether these scientists agreed with

the assessment that I have heard from all of the other

scientists——

Chairman GORDON. The gentleman’s time has expired, but let me

suggest that if you will put those questions in writing——

Mr. ROHRABACHER. Okay.

Chairman GORDON.—that the panel will have an opportunity to

give you the best answer that they can.

Mr. Baird.

MORE ON THE IPCC PROCESS

Mr. BAIRD. I thank the gentleman.

I thank the expert testimony.

Is it correct that there were 450 Lead Authors, 800 contributing

authors and over 2,500 reviewing authors who participated in this

study or this Report? Is that an accurate——

Dr. SOLOMON. That is the number across all three Working

Groups, sir. For Working Group I, the numbers are in my testimony, 152 Lead Authors, 400 contributing authors, 600 expert reviewers.

Mr. BAIRD. Was there a——

Dr. SOLOMON. The numbers that you quoted are for group I, II,

and III that you were——

Mr. BAIRD. Okay.

Dr. SOLOMON.—talking about. We are Group I only.

Mr. BAIRD. Thank you. Was there an effort to intentionally exclude people who might have a different opinion about global

74

warming, or were people allowed to participate and offer comments

if they disagreed with global warming hypotheses?

Dr. SOLOMON. The review process was entirely open. Scientists

could register on the web. They only had to say who they were.

They weren’t asked anything else, and they were sent whatever

materials they wanted to review. So it was totally open to anyone

who wished to review it.

Mr. BAIRD. So presumably, if they had had compelling arguments

and data to persuade their colleagues to reach contrary conclusions, they had ample opportunity to do that?

Dr. SOLOMON. They had ample opportunity to express their

views, indeed.

Mr. BAIRD. Dr. Trenberth, you seem to want to comment.

Dr. TRENBERTH. In my chapter, yes, there were many wellknown, so-called skeptics that participated as reviewers, and their

comments were all addressed.

Mr. BAIRD. So it would not be accurate to suggest that this was

somehow a biased report, and one could actually see if there

were—some of my colleagues are raising questions that they have

heard from so-called skeptics, one could see those answers to the

skeptics in the Report or presumably in the web dialogue that led

to the Report?

Dr. TRENBERTH. The Report is changed, of course, in response to

comments, but there are many comments. And in addition, all of

the comments are responded to in writing, and there is a file, there

is a great big file at the technical support unit, which has the responses to every comment and how they were addressed.

MORE ON GLOBAL WARMING TRENDS

Mr. BAIRD. I appreciate that.

So what you are saying is there is a baseline level of CO2 produced by agricultural processes, sea changes, et cetera, the normal

kind of fluctuations? But beyond that baseline, we have seen a substantial increase in CO2 that correlates quite closely to the production of CO2 by human-related activity, i.e., predominantly the consumption of fossil fuels. Would that be a fair statement?

Dr. SOLOMON. Indeed. Figure 1 of the Summary for Policy-makers shows a constant CO2 for 9.9 thousand years, approximately,

followed by a dramatic increase in the last century, which is essentially entirely attributable to human activities.

Mr. BAIRD. So to sum—while it is an intriguing question to ask,

what percentage of the total CO2 budget is produced by human activity in terms of gauging changes in the CO2 budget, which may

correlate to changes in temperature. It may, in fact, be the change

that is of most significance and importance for understanding here,

not just the base level—the differential percentages, because prior

to that, presumably, the CO2 production of humankind was background, a rounding error, possibly.

Dr. SOLOMON. I am afraid I don’t know the number exactly, but

again, in terms of concentrations, 270 parts per million by volume

in, say 1700, 270 parts per million 1,000 years before that, today,

380 parts per million, sir, so——

Mr. BAIRD. So could we not assume that is 110 parts per million?

75

Dr. SOLOMON. 110-part-per-million increase due essentially entirely to human activity. That is what I am trying to say.

Mr. BAIRD. So 110 parts per million is what——

Dr. SOLOMON. Out of 270.

Mr. BAIRD. Correct. So that is about, what——

Dr. SOLOMON. A third.

Mr. BAIRD.—30 percent. So that may answer the gentleman from

California’s question, I think, and that is what I was trying to get

to earlier.

But more importantly, in terms of the global warming debate, if

you have got that increase presumably in, I think—we cannot dispute that we produce more CO2. I mean, that would be pretty hard

to dispute on any credible scientific grounds. We also seem to have

pretty clear evidence from this Report of the increase in temperature. While correlation is not causation, correlation can give us

some pretty good insights.

One final question. Skeptics may ask you to prove beyond a

shadow of a doubt that this global warming, which we are observing, is caused by human consumption—production of CO2. I don’t

think that is scientifically possible. I used to teach scientific method. I hold a doctorate in the scientific field. You can’t do it. But

that doesn’t mean one does not act on the best available scientific

information. Will you care to comment on that?

Dr. MEEHL. Yeah, maybe I can comment on that.

The real big advance we have seen in the last five years with trying to address this question of attribution, that is basically your

question, you know, how can we attribute, how can we be sure that

humans are causing this warming, are these computer climate

models we use, and they have been improved quite a bit. We have

been putting in single factors that we think affected climate over

the 20th century, natural and human-produced. So we can put in

solar variability by itself in the model, run it for the 20th century,

see how the climate system responds. We can put volcanic activity

in. We get a big volcano going off that cools off the climate for a

couple of years and see how that responds. We can put in other

forms of air pollution, sulfate aerosols, which are small particles

that reflect sunlight, so that is a cooling effect. We can put that in

separately and see how it affects the climate. We can put in increases of greenhouse gases produced by human activity and see

how that affects the climate. So we can deconstruct the 20th century climate in a way that we just couldn’t do taking observations,

because the observations you are seeing out the window are a combination of all of these factors wrapped up together. There is a

great use of these models as tools, so we can actually look at each

of these things separately and in combination to see how they contributed to what we observed over the 20th century. And as was

alluded to earlier, the results from these studies, the first started

to be done about five years ago, and we have many more now that

we assessed, show that most of the warming that we observed in

the first part of the 20th century was natural. Not many volcanoes

were going off. We had an increase of solar output. Then we had

the level period from the 1940s to the 1970s when the big increase

in industrial activity after World War II produced a lot more air

pollution. That was a cooling effect, but the increase in greenhouse

76

gases were still going up. That was warming, but they about balanced until about the mid-1970s. Then the ongoing increases of

greenhouse gases plus some efforts by industrialized countries to

reduce visible air pollution then produced the big warming we have

seen since the 1970s.

So I think by being able to do these kinds of studies with these

calibrated models, we can make this statement that it is very likely

that most of the warming we have seen in the last half-century or

so is due to human activities. That is where that comes from.

Mr. BAIRD. I appreciate that and yield back.

Chairman GORDON. Thank you, Dr. Meehl.

Mr. Sensenbrenner is recognized for five minutes.

Mr. SENSENBRENNER. Yes. Thank you very much.

I would like to ask members of the panel to rank the three big

greenhouse gases, CO2, methane, and NOΧ as to which is the biggest culprit, which is the second biggest, and which is the third biggest.

Dr. SOLOMON. Figure 2 of the summary shows that explicitly, so

what you can see there is that carbon dioxide is the largest contributor. Methane is the second. Nitrous oxide is also significant, and

that is shown in the middle of the second column. And the

halocarbons also contribute. Tropospheric ozone does as well.

Mr. SENSENBRENNER. Okay. Now——

Dr. SOLOMON. You can see the ranking, sir.

Mr. SENSENBRENNER.—by looking at your Figure 1, Dr. Solomon,

CO2 has gone up about 40 percent since 1750 whereas methane

has gone up, by my rough figures, about 130 percent. What is causing the difference between the increase of human activity is the

culprit on all of that?

Dr. SOLOMON. The sources are different. In the case of methane,

the primary sources are agricultural, whereas in the case of carbon

dioxide, the primary sources are fossil fuel, so they are coming from

different things.

Mr. SENSENBRENNER. Does that mean that to stop this huge

growth of methane, we better put catalytic converters on the back

of cows?

Dr. SOLOMON. Certainly, animals are one contributor to the increases in methane. You are quite right. There are——

Mr. SENSENBRENNER. Now you are hitting the Wisconsin economy right between the horns.

Dr. SOLOMON. I can always tell you I love your cheese, sir. I don’t

know what else to say.

Mr. SENSENBRENNER. Well, we better make sure that there are

cows there to produce it, and we appreciate your patronage.

Dr. Trenberth.

Dr. TRENBERTH. Yes. I am from New Zealand, and it turns out

New Zealand is pretty unique in that it emits more methane than

carbon dioxide because of all of the sheep and cows in New Zealand, and there is a tremendous amount of research going on on

exactly that topic and how to change feed in order to reduce methane coming out of the mouths and the other end of animals.

77

GREENHOUSE GAS PRODUCTION: COUNTRY COMPARISONS

Mr. SENSENBRENNER. Okay. Have you done any figures or any

calculations as to which particular countries are culprits in emitting more or less CO2 and methane relatively? Meaning, do you see

more methane in Europe and more CO2 in North America, or don’t

you know?

Dr. TRENBERTH. There are charts on those. I don’t have those

numbers at my fingertips. And the other revealing factor, which

you may want to look into, is the amount per capita, and I do know

that the United States leads the world in both categories. And that

per capita, the United States emits about two and a half times

more carbon dioxide than in Europe, for instance, and about 10

times more than China and about 20 times more than India, but

of course, the per capita aspect and the number of people then

makes a very big difference, and so that is another important——

Mr. SENSENBRENNER. Well, now, you know, I was the head of the

Congressional Observer Delegation to Kyoto, so I went and

watched all of that stuff. One of the meetings that my bipartisan

delegation had was with the Chinese delegation. And they told Mr.

Dingell that they weren’t going to cut down on their greenhouse

gas emissions, no way, no how. Mr. Dingell kept on going forward

for 20 years, seeing if they would change their mind, and if I didn’t

tell him to stop, he would still be there, and we would probably be

up to the year about 15,000. The Chinese Government, last week,

when your report was coming out, reiterated the fact that it was

going to stonewall dealing with this issue because it needed to burn

more hydrocarbons in order to develop its economy. If you have the

world’s biggest country and the world’s most rapidly developing

economy not participating in this and the United States, for example, doing what has been suggested here, have you thought about

the economic impact on where jobs go, meaning to China and away

from the United States?

Dr. TRENBERTH. It is not for me to really say that, but I would

emphasize, indeed, that this is a global problem, and so whereas

other countries are concerned about the United States’ emissions,

indeed, I think we need to be concerned about other countries’

emissions and therefore the international negotiations are an important part of this problem.

Mr. SENSENBRENNER. But with all due——

Chairman GORDON. The gentleman’s time has expired.

Mr. Udall.

CLIMATE RESEARCH

Mr. UDALL. Thank you, Mr. Chairman.

I would note for my colleague from Wisconsin that Dr. Bartlett,

who has just recently traveled to China, had some very interesting

discussions with the Chinese, and I am going to maintain my own

time, but I am hoping to cue Dr. Bartlett, and perhaps when he

has some questions, to talk about what the Chinese are doing. So

their actions are speaking, certainly, as loud as their words. They

understand that the present path cannot be maintained in any sustainable fashion.

78

Dr. Trenberth, I want to turn to your testimony. You restate the

Report’s findings that we’re already committed to a significant level

of climate change in that you believe we need to mitigate the effects of the coming changes. And I might like to, in that spirit, note

that yesterday I introduced H.R. 906, the Global Change Research

and Data Management Act of 2007, along with my good friend and

colleague from South Carolina, Mr. Inglis. And this bill updates the

existing law that formally established the U.S. Global Change Research Program in 1990, and it would help reorient the research

program to be more user-driven, which would help local and state

and regional and national policy-makers make more informed decisions.

Would you speak to that from your point of view? Do you believe

that improving these regional models would enable us to produce

these vulnerability assessments that you reference in your document?

Dr. TRENBERTH. One of the things that we struggled with in our

chapter in dealing with observations is that in a number of countries, in fact, observations, especially the surface observations, are

decaying over time. And as a recent National Academy of Sciences

report has stated, there are real risks in losing a lot of space-based

observations in the future. Space-based observations are very difficult to deal with, as well, because every time you put a new satellite up with a new instrument, it is very hard to know exactly

how those measurements relate to the previous set of measurements. And so it depends on whether these satellites have been

launched for climate purposes and whether the observations are

adequately calibrated or whether they are launched for other purposes, such as weather, where those issues are not so great. And

what the science community is certainly urging is that we pay

more attention to these kinds of issues and the degradation that

is going on in the observing system, because this builds the information base as to what is going on and also why. So in this case,

we are not just talking about observations of temperature and precipitation, and so on, but also the observations on why the climate

is changing, what is happening to the composition of the atmosphere, what is happening to the sun, and so on, and I think there

is a very compelling case that we need to do more in this area to

track why this winter in the East Coast was so warm up until recently, why there has been no snow and it has been very warm in

Europe, and they are having trouble with the World Cup Skiing,

what the role of El Nin ̃ o is in this, which is playing a role, understanding the variability and the climate change aspects and tracking what is going on. This relates to natural variability as well. If

it is natural variability playing a role, we should be able to measure it and account for it. So if the ocean currents are changing, the

Gulf Stream is changing, we should be able to measure that and

assess its impact and whether or not there is going to be a shut

down in the Gulf Stream and so on. So I think a compelling part

of what we need to do, also, is to build an information base and

a climate service that addresses these kinds of concerns.

Mr. UDALL. Doctor, is it fair to say what you are proposing and

suggesting we could do is gathering and assessing and concluding

about the data, it is—you are not involved in the processing, okay,

79

what do we do about carbon emissions? And the reason I am asking you that is to promote the idea behind this legislation I proposed, which is to make better use of our resources, be more efficient in this whole area of research, and then we can continue to

have the debate that we are having here and all over the world.

Dr. TRENBERTH. Yeah, the mitigation aspects are dealt with in

Working Group III, and I would urge you to wait for their report

in May of this year. It is not an area where I am an expert. All

I can say is, for myself, I have put solar panels on the roof of my

house.

Mr. UDALL. Thank you.

Dr. Solomon, somebody suggested that—particularly on the heels

of Mr. Sensenbrenner’s comments about methane, that humans are

actually temporary carbon sinks and that we could think about

ourselves in that regard, but I have never seen a study on the balance between humans as carbon sinks and the methane that we

may or may not emit. Be that as it may, what surprised you of the

IPCC process?

Dr. SOLOMON. That is an interesting question. I knew pretty well

what to expect, having been involved in it for a very long time. I

think what surprised me the most was actually how much progress

we have, in fact, made from remarkable new databases, from satellites on issues, such as the effects of aerosols, as Kevin was saying, the improvements in observations. Indeed, there is more to be

done there, but we just have so much better information now. The

advances in modeling, I was very impressed, actually, by the degree of progress we were able to make in this assessment compared

to the past one. It surprised me.

Chairman GORDON. Thank you, Mr. Udall. Your time is expired.

Mr. Calvert, you are recognized for five minutes.

CARBON SEQUESTRATION

Mr. CALVERT. Thank you, Mr. Chairman.

I am going to go at this in a different direction. I think that there

is pretty much unanimity that there is climate change taking place,

global warming taking place, and this committee is gathering information, scientific information within our jurisdiction. And I assume

that information will be shared with other committees that will

have the jurisdiction to regulate certain industries, such as the coal

industry, the automobile industry, the hydrocarbon-fired energy

sources within the United States. And so it is important that we

try to get it right, because the unintended consequences of taking

bad information and trying to make policy is going to have dramatic effects on the economy of this country and certainly for the

rest of the world. And so when Mr. Rohrabacher, for instance, is

asking the question how much of a percentage, for us laymen, is

greenhouse gases relative to natural sources, that is an important

question, because—and also, the question of what countries and

what regions have an increase relative to natural sources for—we

have a better understanding of how we go about that problem. But

it has been said that the United States produces 25 percent—or

uses 25 percent of the energy in the world, and it is about four percent of the world’s population. So you know, you could say that the

United States, overwhelmingly, has the most responsibility to reguVerDate 11-MAY-2000 16:09 May 12, 2008 Jkt 032966 PO 00000 Frm 00091 Fmt 6633 Sfmt 6601 C:\WORKD\FULL07\020807\32966.TXT SCIENCE1 PsN: SCIENCE1
80

late its economy in order to meet its responsibilities, especially

under the Kyoto accord, which I went to with Mr. Sensenbrenner

a number of years ago. So we have got to get it right, because I

would suspect the four of you all agree that with the summary of

the report, 90 percent confidence that human activity is the cause

of global warming. Would you say that all four of you agree to that

basic concept, since you are here, obviously, testifying for the majority? And so if, in fact, that is correct, how do we go about tackling this problem? And I think that that is really what this Congress is going to be trying to answer, whether we go into mandatory caps, which was mentioned by the Speaker, or, as I believe,

incentives in the economy to bring on new industries that I think

will have the same result in the long-term and in the short-term

of having—the result of having less greenhouse gases. In that,

China—the issue of China has been brought up. I believe China,

right now, is opening a new coal-powered plant once a week. And

is that approximately correct?

Dr. TRENBERTH. It is less than every three days.

Mr. CALVERT. Less than every three days. The United States—

the largest energy source within the United States is still coal,

based on our base load power. And I know we are trying to get the

clean coal technology. Doctor, do you think that that is possible,

that we can sequester the CO2 that is put out by the coal industry?

Do you think that is a possibility and continue to use coal?

Dr. TRENBERTH. This is not an area where I am an expert. It is

certainly an area where that potential is, I believe, growing. And

there is, of course, some cost to that, but it needs to be balanced

against the cost of not doing it as well. But——

Mr. CALVERT. Well, right now, the renewable energy sources in

the United States are approximately less than five percent. Ninetyfive percent of all energy source in the United States is hydrocarbon-based or nuclear-power-based. Twenty percent of the base

load in the United States is nuclear. The rest of it is either coal

or gas-powered plants. And so in order for us to really meet the

goals that are outlined within the scientific information that is

being represented to us, without coal or nuclear power, is that possible? I mean, can we have a sustainable economy without coal or

nuclear power?

Dr. SOLOMON. You know, I would just like to emphasize, sir, that

this group are physical scientists. That is all we are. We are not

economists and——

Mr. CALVERT. No, and I understand that. And you are providing

the information that we, as policy-makers ultimately have to make

a determination. Because you know, the automobile industry, the

coal industry, the manufacturing industry in this country are really

depending upon getting it right, getting the right science to us. You

know, something was talked about El Nin ̃ o earlier this year. We

were supposed to have an El Nin ̃ o effect in southern California this

year. Unfortunately, it didn’t happen, and we are having one of the

largest droughts we have ever had. So sometimes, we just don’t get

it right. And so hopefully we get it right when we make these types

of policy decisions.

With that, I yield back the balance of my time.

Chairman GORDON. The gentleman’s time is expired.

81

Ms. Hooley is recognized for five minutes.

ADVANCEMENTS IN CLIMATE RESEARCH

Ms. HOOLEY. Thank you, Mr. Chair. I want to thank all of the

panelists for being here today.

Dr. Solomon, I have a question. There seems to be a big change

in the certainty assigned to this Report compared to the 2001. Was

that because of modeling or was that because of data collection and

observation? And was there——

Dr. SOLOMON. Certainly in both areas. We have really seen advances with, by far, more models, models with better physics in

them, models with improved representation of processes, such as

sea ice and the carbon cycle. We made advances in those areas. In

terms of observations, there have also been many, many advances

in observations. A lot of satellite information has become available

that we just didn’t have before. We now have satellite measurements of sea level rise, for example, for the last 10 years. We also

have satellite data that allows us to say things about the ice

sheets, as Dr. Alley was talking about. And you know, we have also

had more warm years, as I tried to emphasize in the testimony.

And Dr. Trenberth also has emphasized. So the fact that 11 out of

12 of the last years have been among the warmest is a remarkable

and very interesting bit of information.

COOLING IN ANTARCTICA

Ms. HOOLEY. Thank you.

Dr. Trenberth, you say the planet is ‘‘running a fever.’’ Are there

any areas that can get colder instead of warmer as a result of climate change?

Dr. TRENBERTH. In the interior part of Antarctica, it seems as

though it may have even cooled slightly, and we believe that that

is a unique part of the globe because of the ozone hole that occurs

over Antarctica. And so it has created some changes in the atmospheric circulation there that has led to quite warm conditions in

the Antarctic peninsula and the southern part of South America,

the decay of the ice shelf occurred in that region, but at the same

time, perhaps even slightly cooler conditions on the interior part of

Antarctica. So that is one unique area.

IMPACT ON THE WESTERN UNITED STATES

Ms. HOOLEY. Okay. And Dr. Alley, in your testimony, you described the effect of loss of snow pack and—that it will have on the

wintertime water supplies in the west. And since I am from the

West, can you elaborate the impact on our Western states?

Dr. ALLEY. I really can’t, because I am a physical scientist as opposed to an impacts person. What we do observe is that there has

been a shift to earlier snowmelt, and what one sees in projections

of the future is if that continues so that you lose more and more

of your snow pack. And you well know, as a Representative of a

Western state, that the snow pack has been important in maintaining stream flow. Now in terms of what that means for the salmon

versus the farm or versus the irrigation versus drinking water

versus recreation, that is clearly for someone who is wiser than me.

82

But I think you are well aware, and you are probably wiser than

me on these issues.

Ms. HOOLEY. I don’t know about that.

THERMAL EXPANSION OF SEAWATER

Dr. Meehl, would you talk a little bit about the thermal expansion of seawater and the effect it has on global sea levels?

Dr. MEEHL. Yes, water has this interesting property that as it

warms up, it expands. And so as the warming that is taking place

in the climate system penetrates into the ocean, you get ever-increasing layers of ocean water expanding. And as this warming

works its way down into the ocean into a deeper and deeper layer,

you get more and more thermal expansion. So when we talk about

the commitment of climate change, committed warming, it is on the

order of centuries. In other words, we have already committed ourselves to centuries more sea level rise from what we have already

put into the system just because it is going to take centuries for

that warming to work its way all of the way down through the

depth of the ocean. And as long as you still have warming that is

working its way down, you are going to have an ever-increasing

volume of ocean warming up and expanding. So I think that is an

important and probably one of the best things we can quantify in

terms of sea level rise is thermal expansion. These other aspects

related to ice sheets and things like that we have less confidence

in.

MITIGATING CLIMATE CHANGE

Ms. HOOLEY. How much time do we have to turn back the clock

or do something about it?

Dr. MEEHL. Again, that is kind of a mitigation question, and that

is, frankly, out of my area of expertise, but I think just what we

can say from the scenarios we have looked at for the 21st century

where we see that what we do makes a difference. If we go on a

low-emission track, we get less warming. If we go on a high-emission track, we get more warming. And the longer we wait to do

something, the worse the problem gets, the harder it is to try to

do something about it. So I think those kind of very general conclusions you can draw from the projections chapter in the AR4. In

terms of details on exactly how to mitigate the problem, this combination mitigation and adaptation, that is out of our area of our

expertise.

Ms. HOOLEY. I would like to ask the other panelists if you can,

what do you think about how much time we have to turn this

around or change things or try to lower those emissions significantly?

Dr. TRENBERTH. Let me comment. As is clear from the observations, there are already changes underway. I mean, they are already with us, and some of those changes are really, perhaps, already having devastating effects. We mentioned drought, and

drought has become widespread in the subtropics in particular, and

parts of Africa have suffered greatly from that and our understanding is building now that a component of this is very likely asVerDate 11-MAY-2000 16:09 May 12, 2008 Jkt 032966 PO 00000 Frm 00094 Fmt 6633 Sfmt 6601 C:\WORKD\FULL07\020807\32966.TXT SCIENCE1 PsN: SCIENCE1
83

sociated with the global warming that is going on. So from the

standpoint of Africa, maybe it is already too late.

Chairman GORDON. The gentlelady’s time has expired.

Ms. HOOLEY. Thank you.

Chairman GORDON. Dr. Bartlett is recognized for five minutes.

OCEAN CIRCULATION CHANGES

Mr. BARTLETT. Thank you very much.

Mr. Udall mentioned my recent trip to China. I was very surprised and pleased when they began their discussion of energy and

talking about post-oil. They get it. Somehow, we don’t in this country. I would suggest that there ought to be enormous common

cause between those of us who are concerned that there will not

be a limitless supply of oil in the world and those of us, and I am

in both categories, who are concerned that we are involved in global warming. And I would think that we can harness our joint energies and get more attention to this.

My colleague, Mr. Rohrabacher, is somehow concerned, I believe,

that because humans produce only about 10 percent of the greenhouse gases that what we do, maybe, doesn’t matter much. And I

have a little illustration that may help us to understand that the

total amount of gases up there may be somewhat irrelevant relative to what we can do to change that. If you have a seesaw with

100 pounds on each end and you put another 100 pounds on one

end, that is really going down, isn’t it? If you put 1,000 pounds on

each end as the seesaw and you put another 100 pounds on one

end, it is still going down, isn’t it? So the total amount of greenhouse gases that are up there may be somewhat irrelevant as to

our contribution. Obviously, where our Earth’s temperature is, it is

a balance between the heat we gain from the sun and the heat we

lose. And you know, a very small change can produce enormous effects. I was stunned the other day when I read, and I would ask

you if this is true, that in the last ice age the world was five degrees centigrade, that is nine degrees Fahrenheit, cooler than it is

today. That is correct? And for those that think, gee, a degree or

two, my living room goes up and down three or four degrees. That

doesn’t matter much. Three or four degrees in the world may not

matter much. But nine degrees cooler Fahrenheit, and we were in

an ice age. With ice sheets coming down to southeast Ohio, you can

see the terminal there from those, someone was asking about

where it is warmer and where it is cooler. There is an ironic thing

that could happen as the result of global warming, that is that the

British Isles and northern Europe could become very much colder

because we have a big conveyor belt called the Gulf Stream, which

carries heat from the tropics up there. And obviously, water is not

piling up up there, so it has to come back. And it comes back, because it gets more dense and it drops down. And one of the things

that is happening up there may prohibit this increase in density

and that is the melting of ice up there, which produces fresh water,

which is very much lighter than the salty water. And so if we have

a little bit more global warming, we could shut down the Gulf

Stream. And if you look at where England is on the globe, it is up

about central Canada. I had to stop for refueling in the Emerald

Isle. And that really is incredibly green and warm there in Ireland

84

compared to what it would be if it weren’t for the Gulf Stream. So

we can have enormous changes in climate in certain parts of the

world from relatively small changes in temperature.

I was in Antarctica. I have been to the South Pole twice, and of

course 90 percent of the world’s ice is found there and 70 percent

of the world’s fresh water is found there in Antarctica. We have a

circumpolar stream there, a current, that kind of keeps the warm

waters from the north, well, it is north down there, from coming

in. Are there any hints that the global warming may interfere with

that circumpolar current down there? And if that is true and

warmer northern waters could come down, is it possible that we

could see very much accelerated changes in temperatures down

there? And by the way, if that ice pack melted with all of the others, the ocean levels would rise about 200 feet is my understanding. But 60 percent of the world’s population lives within 200

feet of sea level. Is there a potential that global warming could

somewhat interfere with that circumpolar current down there,

which is keeping the warm waters out and keeping Antarctica the

refrigerator it is?

Dr. MEEHL. Maybe I could try taking a crack at this. All of these

ocean circulation changes you mentioned, and you have a real good

knowledge of it, obviously, are things that we are really concerned

about, obviously, as scientists. And one of the things that is really

getting a lot of attention, due to a certain Hollywood movie that we

all really like, was this sudden shutdown of this overturning circulation in the Atlantic that you mentioned that the Gulf Stream

is a part of. And if it suddenly shut down, the idea was that you

would suddenly get a lot more colder in the North Atlantic, because

you wouldn’t be carrying all of that heat up into the North Atlantic

that the conveyor belt transfers. So we have looked at that in all

of the models that we have run so far. No model that we have run

yet, for the 21st century, for the present century, shows a sudden

shutdown of this overturning circulation, this conveyor belt. They

all show a slowing down of the conveyor belt for the reasons—exactly the reasons you mentioned. It gets warmer and less dense in

the high-latitude North Atlantic, therefore you don’t get as much

sinking, and you just kind of slow down this conveyor belt circulation. But, of course, then that would contribute to less heat transport to the North Atlantic. You think, well, maybe that would give

a cooling. When it turns out, to get that slow down, you have to

have so much of an increase of greenhouse gases in the atmosphere

that the warming itself from those greenhouse gases just swamps,

it overwhelms any small decrease of northward heat transport you

get from the slowdown of this overturning circulation. So we say,

in fact, it is very likely that the overturning would slow down. It

is very unlikely that it would suddenly seize up and stop, at least

in the 21st century. And that is even taking into account possible

contributions from melt water from Greenland and other things

that would add to this decrease in density.

Chairman GORDON. The gentleman’s time has expired—oh, I am

sorry.

Dr. MEEHL. I was just going to say, beyond 2100, we are not as

sure, because there may be odd things in the system we haven’t anVerDate 11-MAY-2000 16:09 May 12, 2008 Jkt 032966 PO 00000 Frm 00096 Fmt 6633 Sfmt 6601 C:\WORKD\FULL07\020807\32966.TXT SCIENCE1 PsN: SCIENCE1
85

ticipated, but for the time periods we looked at, especially to 2100,

we don’t see that.

Mr. BARTLETT. Thank you.

Chairman GORDON. The gentleman’s time has expired.

Chairman Miller is recognized for five minutes.

TROPICAL STORMS

Mr. MILLER. Thank you, Mr. Chairman.

Dr. Trenberth, the IPCC Report and your testimony both referred to one result of global climate change, global warming, as

being the intensity of tropical storms. In the fall of 2005, after the

hurricane season that we had that included Katrina, of course, and

several other catastrophic storms, Category 4 and Category 5, I

can’t recall how many, but several, and they were stunning to look

at in the satellite view of how large and perfectly symmetrical they

were. The press wondered whether there was a relationship between global climate change or global warming and that hurricane

season. And many made many requests of NOAA and NOAA produced a hurricane scientist named Chris Landsea, who treated

those questions as if they were an urban legend and was very

dismissive of that possibility. And as a result, the press kind of

went away on that topic and concluded that was not serious science

that anyone had that question. In fact, there were others within

NOAA, other scientists, who said that yes, the formation of the

tropical storms may be cyclical, as Dr. Landsea had said, but the

intensification is very much related to temperature. What was the

state of the science in the fall of 2005 and what is it now on the

relationship between the intensity of tropical storms and water

temperature?

Dr. TRENBERTH. Indeed, the 2005 season, in fact, it began a little

before that, even with the 2004 season where four hurricanes hit

Florida and there were ten typhoons that ended up hitting Japan,

have raised this question, and there has been a great deal of research that has gone on even after our report, although our report,

I think, is still a fair assessment of the current situation. And we

had a breakout group that dealt with this in Paris, and the statement on page 8 of the SPM is fully consistent with all of the literature that we have reviewed in our report. And maybe I should

read it. It says, ‘‘There is observational evidence for an increase in

intense tropical cyclone activity in the North Atlantic since about

1970, correlating with increases in tropical sea surface temperatures.’’ This is one thing where there is widespread agreement that

if the sea temperatures go up, you get more activity. And we are

seeing that in the North Atlantic. And then the second question is

why are the sea temperatures going up. And certainly, on a global

basis, we know that there is a component of that. We believe it is

close to about one degree Fahrenheit now associated with the increases in greenhouse gases. And then you can argue about how

much of that is occurring in the hurricane regions and so on. There

is some natural variability.

Another key part of our statement also recognizes that ‘‘multidecadal variability and the quality of tropical cyclone records prior

to routine satellite observations in about 1970 complicate the detection of long-term trends in tropical cyclone activity.’’ And so this is

86

saying that, indeed, a lot of natural variability as well as the

greenhouse gas-induced trends that are playing a role, and in addition, the database that we have is not as good as we would like.

And so there are some uncertainties there. But nonetheless, there

has been an increase in activity.

Now the theoretical understanding suggests that, indeed, there

will be an increase in activity of some sort, and that can be manifested in a number of ways. You can have increased numbers, increased intensity, increases in size, increases in duration. And we

don’t have measures of all of those. They are not in the historical

record. We don’t have measures of size adequately. And so this is

a very important question, but there are a number of uncertainties

that remain.

SOCIAL AND ECONOMIC IMPACTS OF CLIMATE CHANGE

Mr. MILLER. Okay. One more question for any of you who wish

to answer.

There have been several references to economic consequences

dealing with greenhouse gases in opening statements and in some

of the questions that were propounded to all of you. Last fall, the

British government released an economic report by Sir Nicholas

Stern, who is a former World Bank economist, a 600-page report

that I admit to not having read. But it concluded that global warming could leave millions homeless and result in as much as a $7

trillion, or 20 percent diminution in the size of the world’s economy

and cause the greatest market failure—greatest economic failure in

the world’s history comparable to the Great Depression and worse

than the Great Depression, worse than the world wars. Knowing

what you know about the consequences of global warming of the

forecast, does that sound right?

Dr. SOLOMON. I would really urge you to wait for the Working

Group III assessment. Those are the people who would be qualified

to make that kind of statement. Also, Working Group II, I believe,

will be dealing with that. This is simply not something that is covered in the Working Group I reports. Sir, I am sorry, but we don’t

have the expertise to respond to this question.

Chairman GORDON. The gentleman’s time has expired. Dr.

Ehlers is recognized for five minutes.

MORE ON THE IPCC PROCESS

Mr. EHLERS. Thank you, Mr. Chairman, and first of all, just a

little housekeeping. I did a quick calculation on the question Mr.

Rohrabacher asked, and my estimate is that 35 percent is the answer.

The other comment I wanted to make, Mr. Chairman, is that I

personally appreciate the fact that the Speaker of the House appeared before this committee and made some comments. First of

all, this is an extremely important issue, but also I think that any

time the leadership pays any attention to this committee is good

because sometimes—personally, not publicly—this is the first time

I said it publicly, but sometimes I think this is the Rodney

Dangerfield Committee. We do incredibly good work here and don’t

get the respect we should. So I hope this is a sign——

87

Chairman GORDON. We had a lot of bills on the Floor today——

Mr. EHLERS. I know.

Chairman GORDON.—yesterday, and previously that I think will

demonstrate that Rodney is out of town.

Mr. EHLERS. I hope that he has moved out permanently.

Having said all of that, just first of all, I want to thank you for

being here. A quick question anyone could answer: this is of course

a summary that you have prepared. When will the full report be

published? Do you know? Dr. Solomon?

Dr. SOLOMON. The full report is being copy-edited and laid out.

It will be available probably around May.

GLOBAL IMPACTS OF CLIMATE CHANGE

Mr. EHLERS. All right. Thank you.

Just a few quick comments. First of all, I think it is very clear

that global warming is occurring, and we can argue about how

much and the causes and so forth, but it is occurring. The next

question is it anthropogenic? It definitely seems to be, either

through industrialization or through farming, as we have heard.

A couple of questions: what about global climate change, by

which I mean the whole picture? We seem to be obsessed here this

morning about global warming, but I am much more worried about

climate change. For example, I am from Michigan. We would certainly welcome a bit of global warming in Michigan, especially this

past weekend when I got up Monday morning and it was ninebelow with a wind chill of 21-below. But I wouldn’t want global

warming at the expense of losing rainfall in Michigan and having

it turn into a place like Kansas or—I guess I can say Texas since

our Ranking Member isn’t here.

That really points to the political difficultly we have. We have

two political problems. One is, if we are talking just about global

warming, which is related to human activity, industrialization particularly, that is an immense political problem, globally, to try to

get people to cut back. And I was opposed to the Kyoto Agreement

because it gave a free card to China, and I knew China was going

to be one of the biggest contributors. So that is one political problem. The other one is that global climate change is going to be good

for some areas of the planet and bad for other areas of the planet.

Now, how far along are you in determining the effects of global

climate change and the impact that it is likely to have on different

parts of the globe? How far along are the models in determining

that and with what accuracy?

Dr. MEEHL. This is sometimes referred to as the winners and losers issues. We didn’t really address that in the Working Group I

Report. That is really a Working Group II impacts question. But

when I get asked this question—you know, we have said a lot

about changes in weather and climate extremes. And one of the

changes we have seen in extremes lately is a decrease in the number of frost days, in other words, nighttime temperatures going

below freezing. This is something we have already observed, and in

the models, we project this to increase in the future, that you will

have warmer nights, and less nights below freezing.

So you can say, well, maybe that is a good thing because maybe

that will expand the growing season length, and we do show in the

88

report that the growing season gets longer because of that. You

have later frost in the fall and then earlier warming up in the

spring. But then there are things like insect infestations that are

affected because, if it doesn’t get as cold in the winter, you don’t

kill off as many of the bugs in the wintertime. They live though

the winter, and then you have severe problems with insect infestation. Out in Colorado, we have seen a lot of problems with that

with pine beetle kill.

So it is kind of a mixed bag, a lot of times. There are some things

that may be better, but then there are other unforeseen consequences, and I think that is what makes me, personally, nervous

because when we are moving into a new regime, which we are,

which we have never really observed before, there are things that

we can anticipate that could have good consequences, but other

things that have bad consequences. And that is the part, at least,

that hopefully Working Group II will address in more detail.

Mr. EHLERS. Well, that is precisely my concern because in our

arena—now, I am a scientist, but I ended up in this arena. That

is where the decisions are made in those issues, and we need the

information to make intelligent decisions, and the sooner you can

develop comprehensive models that can deal with those issues, the

better off we will be in this arena.

Chairman GORDON. Thank you, Dr. Ehlers. You got bonus time

for nice comments. Mr. Lipinski is recognized for five minutes.

MANAGING WATER RESOURCES

Mr. LIPINSKI. Thank you Mr. Chairman. Thank you for holding

this hearing on this very important topic that I am very hopeful

will move forward in this Congress in a bipartisan fashion. I am

working on this issue, and I appreciate the testimony that all of

you have given. I understand that your role here is to talk about

the science behind what is going on. In the future I am sure we

will have many panels where we will talk about what can be done

to mitigate this, but than you for bringing you expertise to us

today.

I want to ask—I am from the Chicago area, and I represent part

of Chicago, and I want to ask Dr. Trenberth: you talked about

managing water resources in the future as climate change progresses. Now, I am just wondering if there is anything you can tell

us, perhaps not, but I was wondering if there was anything you

could tell us about how these atmospheric changes may effect Chicago and other areas like that. I mean Chicago uses about two billion gallons of water per day, from Lake Michigan. Is there anything you can tell us about that?

Dr. TRENBERTH. As the climate warms, the water-holding capacity of the atmosphere goes up about four percent per degree Fahrenheit, and we find from the observations that this is actually happening over the ocean. Over the land, it is happening at a slightly

less rate. But it means that there is more water vapor in the atmosphere. Now when you have a storm, the storm reaches out and

grabs the available water vapor, concentrates it and dumps it down

in the form of rainfall. So with more water vapor in the atmosphere, you expect that when it rains, it is going to rain harder, or

even when it snows, it can snow harder, and that is what we are

89

actually seeing. And so you get heavier rainfall events. This is

what is also predicted in the models. However, when that happens,

you also deplete the water vapor in the atmosphere, so you change

the frequency of these events, and it may be that they are more

intense but they may be a little bit fewer and farther in between,

and so you have a greater risk of drought in between. There is a

little bit of extra heat available, so the drying effects of that exacerbate drought.

Ironically, then you get both extremes of what we call the water

cycle that are affected by global warming, and it means that the

challenge of water resource management is that they have times

when they have got too much of a good thing, too much rainfall,

a risk of flooding, and then there are times in between when they

don’t have enough. This is particularly what that comment refers

to: the changing character of precipitation, the changes in snow to

rain, it also means that you have less snow pack going into the

spring and summer, which is when you most need the water, so

that aspect of management is another key part of it. And so these

are the factors that play into the water management challenge.

MORE ON CLIMATE RESEARCH

Mr. LIPINSKI. Thank you, and I want to ask Dr. Alley, you mentioned that the apparent shrinking of the large ice sheets was an

unexpected finding. Why was this unexpected and can you point

out any other findings that came out as a big surprise to you?

Dr. ALLEY. We had a longstanding debate in the community.

How fast can ice sheets do interesting things? They are very large;

they look sluggish. And yet you look back at the history of the climate, back to the Ice Age, and most of the time ice sheets were boring, and occasionally they were really interesting. And so we have

had this longstanding debate in the community are the ice sheets

going to be boring or they going to be interesting, and the assessed

science of the report said the most likely outcome is boring, and

they have been interesting, and that, probably, for me was the

most surprising thing that came out of it.

The other thing that I see, looking at the report, is how good the

science has become on so many things. So the early IPCC reports

picked out sensitivity. You are at double CO2. How much does the

climate warm? And it was based on moderately weak evidence. It

was good science, but there just wasn’t a lot of it. And as the

amount of science has been produced, as more research has been

done, more models, more observations, the quality of the support,

the strength of the conclusions has just become tremendously

greater. So there are a few, you know, gaping holes that we would

love to fill, but primarily the quality of the science is just superb.

It is just outstanding, and results are getting to the sort of poundon-the-table-this-is-right stage. Thank you.

Chairman GORDON. The gentleman’s time has expired. I am told

that the gentleman from South Carolina, Mr. Inlgis is next and recognized for five minutes.

90

OPPOSITION TO CLIMATE CHANGE

Mr. INGLIS. Thank you, Mr. Chairman. I am one of those people

that used to poo-poo global warming. It seems to me it is hard not

to be persuaded with the evidence that you have been talking

about. There is always the question of causation, so I would make

the analogy to the doctor who determines it is genetics that determines longevity. Doctor, would it hurt us to diet and exercise? Not

likely to hurt us. So it is not likely to hurt us to take some action,

as long as we can do that in a way that maintains balance with

other things that we have got to do in life, like make a living and

provide for our families and all of those kinds of things. So it seems

to me the key is to work cooperatively to solve some of these challenges.

It is going to be hard, though. I read yesterday, Mr. Samuelson’s

piece, Mr. Chairman, that I asked to insert in the record. It is Robert J. Samuelson, ‘‘Global Warming and Hot Air.’’ And basically describes just how difficult it is going to be and address the challenges at hand. But there are some real opportunities, for example,

reinventing the car so that it runs ultimately on hydrogen, let us

say, or batteries, or something that doesn’t emit CO2. What an exciting opportunity for us to make money, which is great thing too,

and to clean the air, and to improve the national security of the

United States. But it is going to be hard.

I think we made progress here, today, Mr. Chairman, with the

Speaker’s open-mindedness to looking at nuclear power. That is a

very significant development here today, I think. And it shows a

level of cooperation I think we all need to have: come with open

minds about how to solve this challenge.

Part of the change in my thinking came from a wonderful trip

to Antarctica about this time last year with a number of Members

who are here today, led by Sherwood Boehlert, and perhaps one of

you can help me relearn what I think I learned there about the

methodology of the ice cores, the drillings, and what we found

there. Can somebody describe that so I can relearn, and maybe, I

can just learn?

Dr. ALLEY. Happily. I have worked on ice cores in many places,

Antarctica and Greenland, and essentially an ice core is like a really fancy drill. If you were going to put a knob in your door, you

would just take a pipe with teeth on the end, you would spin it,

you would run it down, you pull out a piece of ice, and you would

do that until you have two miles of it. And if you break the bubbles, that is a little bottled sample of old air. You can find out

whether carbon dioxide was higher or lower in the past. Very high

confidence that this works. It matches the instrumental record over

recent times, different cores from different places with different

temperatures and different snowfall rates give the same answers.

And so what shows is that the level of carbon dioxide, the level of

greenhouse gasses that we have in the atmosphere, are unprecedented, at least for the last 650,000 years.

Mr. INGLIS. And going back to some earlier questions. What is

the chance of that happening as a result of natural phenomena,

that significant increase?

91

Dr. ALLEY. If one looks at a long record like that and says, well,

it surely looks now like we are above what nature has done for the

last 650,000 years, and it happened in the last 1000, that would

seem unlikely. In addition, we very clearly—oil companies are quite

good; they know how to find oil. Coal companies are quite good;

they know how to find coal. And we know how much they found,

so we know how much is being burned. We know how much carbon

dioxide is going into the air, and we know where it is going, and

sort of our fingerprint is on this with very high confidence.

Mr. INGLIS. For those who dispute that, what is their best argument? Where can they find some data besides what you just reported on?

Dr. ALLEY. I truly don’t know what a really good argument is

against this. There are a number—we have the budget. We know

what is going up, what is going down. But then you can ask, well,

is there evidence of that? Maybe your budgeting is wrong. And

then you say—but carbon isotopic composition of fossil fuels is different than the carbon isotopic composition that was in the air.

And we can see the change over time as humans are putting fossil

fuel CO2 up. That applies both to the stable carbon and to the radioactive carbon. We are diluting the natural radiocarbon in the atmosphere by putting old carbon up from below. One can see the

very, very tiny change in oxygen composition that goes with burning the fossil fuels. So once you say, well, we know the budget,

then, someone will say, well, are you are right about that. Then,

you say, well, if we are right, then you should say this in the stable

carbon, you should see that in the radioactive carbon, you should

see the others in the oxygen, and you see all of those.

Chairman GORDON. The gentleman’s time has expired. The Gentleman from Kentucky.

Mr. INGLIS. Mr. Chairman, a reminder to insert that in the

record, the Samuelson piece, without objection?

Chairman GORDON. Without objection.

[The information follows:]

INFORMATION FOR THE RECORD

Global Warming and Hot Air

BY ROBERT J. SAMUELSON

Washington Post

WEDNESDAY, FEBRUARY 7, 2007; A17

You could be excused for thinking that we’ll soon do something serious about global warming. Last Friday, the Intergovernmental Panel on Climate Change (IPCC)—

an international group of scientists—concluded that, to a 90 percent probability,

human activity is warming the Earth. Earlier, Democratic congressional leaders

made global warming legislation a top priority; and 10 big U.S. companies (including General Electric and DuPont) endorsed federal regulation. Strong action seems

at hand.

Don’t be fooled. The dirty secret about global warming is this: We have no solution. About 80 percent of the world’s energy comes from fossil fuels (coal, oil, natural

gas), the main sources of man-made greenhouse gases. Energy use sustains economic growth, which—in all modern societies—buttresses political and social stability. Until we can replace fossil fuels or find practical ways to capture their emissions, governments will not sanction the deep energy cuts that would truly affect

global warming.

92

Considering this reality, you should treat the pious exhortations to ‘‘do something’’

with skepticism, disbelief or contempt. These pronouncements are (take your pick)

naive, self-interested, misinformed, stupid or dishonest. Politicians mainly want to

be seen as reducing global warming. Companies want to polish their images and exploit markets created by new environmental regulations. As for editorialists and

pundits, there’s no explanation except superficiality or herd behavior.

Anyone who honestly examines global energy trends must reach these harsh conclusions. In 2004, world emissions of carbon dioxide (CO2, the main greenhouse gas)

totaled 26 billion metric tons. Under plausible economic and population assumptions, CO2 emissions will grow to 40 billion tons by 2030, projects the International

Energy Agency. About three-quarters of the increase is forecast to come from developing countries, two-fifths from China alone. The IEA expects China to pass the

United States as the largest source of carbon dioxide by 2009.

Poor countries won’t sacrifice economic growth—lowering poverty, fostering political stability—to placate the rich world’s global warming fears. Why should they?

On a per-person basis, their carbon dioxide emissions are only about one-fifth the

level of rich countries. In Africa, less than 40 percent of the population even has

electricity.

Nor will existing technologies, aggressively deployed, rescue us. The IEA studied

an ‘‘alternative scenario’’ that simulated the effect of 1,400 policies to reduce fossil

fuel use. Fuel economy for new U.S. vehicles was assumed to increase 30 percent

by 2030; the global share of energy from ‘‘renewables’’ (solar, wind, hydropower, biomass) would quadruple, to eight percent. The result: by 2030, annual carbon dioxide

emissions would rise 31 percent instead of 55 percent. The concentration levels of

emissions in the atmosphere (which presumably cause warming) would rise.

Since 1850, global temperatures have increased almost one degree Celsius. Sea

level has risen about seven inches, though the connection is unclear. So far, global

warming has been a change, not a calamity. The IPCC projects wide ranges for the

next century: temperature increases from 1.1 degrees Celsius to 6.4 degrees; sea

level rises from seven inches to almost two feet. People might easily adapt; or there

might be costly disruptions (say, frequent flooding of coastal cities resulting from

melting polar ice caps).

I do not say we should do nothing, but we should not delude ourselves. In the

United States, the favored remedy is ‘‘cap and trade.’’ It’s environmental

grandstanding—politicians pretending they’re doing something.

Companies would receive or buy quotas (‘‘caps’’) to emit carbon dioxide. To exceed

the limits, they’d acquire some other company’s unused quotas (‘‘trade’’). How simple. Just order companies to cut emissions. Businesses absorb all the costs.

But in practice, no plausible ‘‘cap and trade’’ program would significantly curb

global warming. To do that, quotas would have to be set so low as to shut down

the economy. Or the cost of scarce quotas would skyrocket and be passed along to

consumers through much higher energy prices. Neither outcome seems likely.

Quotas would be lax. The program would be a regulatory burden with little benefit.

It would also be a bonanza for lobbyists, lawyers and consultants, as industries and

localities besieged Washington for exceptions and special treatment. Hello, influence-peddling and sleaze.

What we really need is a more urgent program of research and development, focusing on nuclear power, electric batteries, alternative fuels and the capture of carbon dioxide. Naturally, there’s no guarantee that socially acceptable and cost-competitive technologies will result. But without them, global warming is more or less

on automatic pilot. Only new technologies would enable countries—rich and poor—

to reconcile the immediate imperative of economic growth with the potential hazards

of climate change.

Meanwhile, we could temper our energy appetite. I’ve argued before for a high oil

tax to prod Americans to buy more fuel-efficient vehicles. The main aim would be

to limit insecure oil imports, but it would also check CO2 emissions. Similarly, we

might be better off shifting some of the tax burden from wages and profits to a

broader tax on energy or carbon. That would favor more fuel-efficient light bulbs,

appliances and industrial processes.

It’s a debate we ought to have—but probably won’t. Any realistic response would

be costly, uncertain and no doubt unpopular. That’s one truth too inconvenient for

almost anyone to admit.

 2007 The Washington Post Company

Mr. INGLIS. Thank you, sir.

Chairman GORDON. Mr. Chandler from Kentucky is recognized

for five minutes.

93

CLIMATE CHANGE SCENARIOS

Mr. CHANDLER. Thank you, Mr. Chairman. I do not need to be

persuaded. I think I can see facts rather clearly when they are presented. I had the opportunity, along with the gentleman from

South Carolina, to go on that Congressional Antarctic sojourn last

year, and it was a truly eye-opening experience. We saw a lot and,

I think, got a pretty clear picture of what the science—at least the

science that people were working on down there—showed. One

thing that is abundantly clear is what the graphs show in the last

handful of years, and that is shocking, truly shocking, to see the

change in terms of warmth in the atmosphere in a really surprisingly short period of time. And frankly, it is just hard for me to

imagine that fossil fuels can be deposited in the Earth over hundreds of millions of years and can be released in the amounts that

they have been released in, in a very short period of time, without

having some dramatic effect on the atmosphere. It just goes against

any sort of reasonable thinking.

And I would like to know, can you give us any idea about how

quickly you feel this process is going to speed up in the near-term,

this warming process? It has been quite dramatic in the last decade

or two. Do you look for that speed, that sort of dramatic uptake to

continue in the next couple of years? Do you think it will speed up

exponentially?

Dr. MEEHL. Well, I think what we have seen from the scenarios

we have run with the models is that pretty much no matter scenario we are on, the next 20 or 30 years, the warming is going to

be about two-tenths of a degree centigrade, per decade. And of

course, that is barring any huge volcanic eruption that would cool

it down for a year or two. But from the anthropogenic or humancaused part, we are on a track now for another, for about two-tenth

of a degree C warming over the next few decades. But having said

that, when you get past about the 20s, 30s, then you will start seeing the scenarios really starting to spread.

Mr. CHANDLER. You mean a big spike?

Dr. MEEHL. A spreading out. The high emissions give you more

warming and the low emissions give you less warming. So we kind

of have this very consistent warming no matter what scenario we

are on for the next 30 years, and then you start seeing the spread.

But having said that, it does make a difference what track we are

on because we are setting ourselves on a course now to follow one

of these outcomes and depending on if we are on a high-emissions

outcome, we are going to get a lot more warming. If we are on a

low-emissions outcome, we are going to get less warming. So I

think what we do now does make a difference for the future.

MORE CLIMATE CHANGE SCENARIOS

Mr. CHANDLER. Now, I would like to ask a question about the ice.

Dr Alley, you have mentioned something on ice sheets being boring.

The same, certainly, cannot be said about you. I can’t help but ask,

what do you think is going to happen? I heard predictions of dire

results in the Arctic, among other places, largely because, as I understand it, because there is no land up there, and that makes a

big difference in all of the forces that are involved there. Can you

94

make some kind of a prediction about what you think is going to

happen to the Arctic and how quick you feel that result will occur

if we do nothing?

Dr. ALLEY. There are a number of assessed-model results in the

report looking at the sea ice of the Arctic Ocean, which is the frozen ocean water, and I don’t have the quota in front of me, but

some of the extreme warming scenarios in some of the models get

to a no-sea-ice in the summer in the Arctic at the end of this century, so fairly large changes showing up in the frozen ocean water.

Mr. CHANDLER. All gone?

Dr. ALLEY. For the late summer, in the more extreme warming

scenarios, in some of the models, and it would grow back in the

winter in those models. So that is the floating part. Then, the part

that is not yet floating, up on Greenland, almost certainly is there

yet in the end of the century, but in the larger warming is melting

fairly rapidly at that point.

Mr. CHANDLER. Which would almost certainly have an impact on

things like the Gulf Stream. A kind of huge impact, wouldn’t it?

Dr. MEEHL. Not so much on the Gulf Stream. I think it is more

on sea level raise. Because in the projections, where models have

included melt from the Greenland ice sheet, like I was explaining

before, it does contribute to slowing down this overturning circulation, but it doesn’t ever actually stop it. But I think the biggest

concern, and something Dr. Alley alluded to, is how unstable something like the Greenland ice sheet is. And this again is in this category as we are moving into an era where we are starting to observe things we have never seen before in recorded human history.

Glaciologists have talked about the possibility of rapid ice-sheet destabilization as a possibility. They have talked about a possible

mechanism. In the last ten years, they started to make observations that maybe this mechanism actually is working. But because

we have a very short time period when we have actually observed

this kind of possible instability, we don’t know what to make of it.

Like Dr. Alley said, is it a temporary thing? Would it be sustained

or accelerated more in the future? And we just don’t know. And I

think that falls under the category of things that we can with certainty and other things that we just don’t know about right now.

This is obviously being researched, and a lot of scrutiny is being

put on this now, so we will have better answers in the next few

years, but right now, we just don’t know.

Chairman GORDON. The gentleman’s time has expired, but I

would assume that there is no good news. It is only bad news that

will be coming from this. The Gentleman from Florida?

SCIENTIFIC CONSENSUS

Mr. DIAZ-BALART. Thank you, Mr. Chairman. First, I want to

thank you for putting this hearing together. I think you brought

some great witnesses. I also want to thank the Speaker. It is always good to bring attention to issues, so obviously, she honored

us this morning.

You know, I am pretty much like Mr. Inglis is, like Congressman

Inglis. I have gone from not knowing much about it, just because

you know, you see Hollywood movies, and that kind of scares me.

The more you read—and being one that always has to—I think we

95

all have to—obviously, since we aren’t all scientists, we have to

rely on the real science as much as possible, so what I keep hearing

more of is that that is where real science is certainly going.

I am asking for some reassurance to make sure that I am leaning

in the right direction. I tell you that before, for example, the more

I read—let me just quote this one thing from the press, ‘‘As for the

present trend, a number of leading climatologists have concluded

that it is very unpleasant news, indeed.’’ They say that it is the

root cause of a lot of the unpleasant weather around the world, and

they warn that it carries potential for human disasters of unprecedented magnitude. I keep hearing about this possibility because of

global warming.

What scares me sometimes is that that is not about global warming. That is an article in Fortune magazine from 1974 about climatologists now blame those droughts and floods on global cooling

trends. I also have, then, from the Washington, January 1970. ‘‘Is

mankind manufacturing a new Ice Age for itself?’’ And it quotes a

number of prestigious scientists who, now, are some of the ones

who believe that they were wrong then and now that we are going

to global warming. ‘‘Winter held dawn of new Ice Age,’’ this is from

the Washington Post. Science Digest, ‘‘Brace yourself for an Ice

Age.’’

If we would have obviously gone ahead and acted because of

what a number of very prestigious scientists would have said then,

we would have been dead wrong—because I have to believe you all.

I really do. I happen to believe you all. So what I am asking for

is reassure me that in 1970 we were still looking at science that

the world was flat and that prestigious scientists were dead wrong,

because that is what I believe because that is what I hear. And

now science has changed dramatically and technology, which is

what I think I have heard today—and that therefore that is wrong,

and that the new consensus that we are in a warming trend is correct, and that therefore I can feel comfortable with that point of

view.

Dr. ALLEY. I will try first, and then maybe my colleagues will

help a little bit.

Mr. DIAZ-BALART. And if I may interrupt you, Mr. Alley, I am

also resentful of the fact that you made me very hungry this morning with your pancake analogies. It is 12:30, and I think that is unfair.

Dr. ALLEY. I apologize for that, yes. We are with you on that one,

actually.

As scientists, you know, our job is to push the limits. I teach at

a very large school, and I can assure you that there are a lot of

very bright students there that are pushing the limits. They are

coming up with new ideas that are going to help us and save us,

and some of it is totally off the wall. And so as scientists, we bubble up all of these interesting ideas, and then you have built mechanisms, we have built mechanisms, the world has built mechanisms, to distill all of these ideas into something which is policyrelevant for you. And so this global cooling, which some of it came

from us learning to understand the Ice Age, and some it came from

a lot of aerosols coming out off smokestacks, blocking the sun, was

something that was bubbled up in a little bit of discussion and

96

huge amount of press interest. But if you go back and ask if the

National Academy actually come out with a global-cooling warning,

you won’t find it. You know, when you get to the point of asking

was the assessed knowledge that was pulled together policy relevant for you? Was that warning about this? Was that the big

issue? I don’t believe you will find it. And so the IPCC here exists

as a mechanism, as does the National Academy. It exists as a

mechanism to take all of these wonderful ideas, this ferment and

froth that is out there in the scientist community, and say what

stands up, what is reliable, and to give it to you. And we are here

to tell you that the assessed science of the world is pointing to

human activities, changing the atmosphere in a way that is causing warming.

Mr. DIAZ-BALART. And I appreciate that.

Mr. GILCHREST. Will the gentleman from Florida yield just for

two seconds on this time?

Mr. DIAZ-BALART. Of course.

Mr. GILCHREST. Having lived through that period of time, and

having read a number of articles and books, born in the 1970s, Dr.

Alley is correct, there was not a consensus that we were cooling.

There was some suggestion, for a variety of reasons—the consensus

was are we cooling or warming. We don’t know yet. So at that

point, there was no consensus.

Chairman GORDON. The gentleman’s time has expired.

Mr. DIAZ-BALART. Could I have a ten-second comment?

Chairman GORDON. With unanimous—we will see if I can get

this unanimous consent. I wasn’t able to get one earlier.

Mr. DIAZ-BALART. Mr. Chairman, I just learned—is it possible

that the press exaggerates on issues? I am just shocked at what I

learned today in this committee. I can’t believe that. I am sorry.

I just can’t believe that.

Chairman GORDON. Okay. Thank you, Professor—or Doctor, was

it? I guess it was Inspector Reneau. And a very patient gentlelady

from Arizona, Ms. Giffords, is recognized for five minutes and ten

seconds extra if she needs it.

IMPACT ON THE SOUTHWESTERN UNITED STATES

Ms. GIFFORDS. Thank you Mr. Chairman. First of all, I want to

thank all of you for coming. It is important that you are here. We

appreciate that you are here. The American people are glad you are

here, and frankly, the world is. This is an area that I so passionately believe that we need to lead in. And I look around at all of

the portraits behind you, particularly that depict America’s mission

to go to the Moon and to explore space and where we lead. And

that Apollo mission of the future, I believe, is in energy and climate

change. And this is just a first start. Mr. Chairman, thank you for

bringing such distinguished speakers here today, and we appreciate your science. We may all not agree, but this is a process

where we deliberate, and I just certainly appreciate being here.

My question reflects my district, which is Southern Arizona, the

most extraordinary district. If you can, imagine Tucson going all of

the way to New Mexico. And this is an area—we are not sure quite,

but eight or nine years of a drought we are experiencing. We are

also seeing some other strange changes that we have just not seen

97

before. We had a very strange storm happen about a year-and-ahalf ago that produced some rockslides in our mountains that we

are not familiar with. We also had some wildfires in Arizona, particularly in the Catalina mountain range, that burned very hot, we

understand, that because of the weevil infestation that has been allowed to build up, because of it not freezing, and the trees then

weakening. So I am just curious and as a former legislator, I tried

to establish a climate-change study group in the Arizona legislature. We brought some distinguished scientists from the University

of Arizona, where they have a global climate center, and frankly,

my colleagues on both sides of the aisle were not polite to the scientists. And even one of my colleagues said well, heck, hot is hot.

What is the difference between 115 degrees or 120 degrees? So I

ask you, and I am not sure which scientist to address this to, if you

could explain in real terms, for the citizens of southern Arizona,

the difference between 115, 116 degrees, 120 degrees. What does

that really mean in the next five years, the ten years, and 50 years

for the people of Arizona?

Dr. TRENBERTH. Well, let me have a crack at this there.

Indeed, the drought in the southwestern parts of the United

States from 1999 to 2004 is one of the things which we think may

be, indeed, symptomatic of the climate changes that are underway

related to global warming. In the winter of 2004–2005, we had

weak to moderate El Nin ̃ o, so there was maybe temporary relief.

We are not quite sure. Certainly, the droughty regions have continued since then. But your concern about temperature, there are a

number of analogs, and perhaps one of the best analogs is the year

2002 which is when the drought in the West and in the Southwest

was most extensive. And one of the things that goes along with the

drought is higher temperatures and heat waves, and in particular,

one of the consequences is wildfires. And the risk of wildfires went

up in 2002, there were a very large number of wildfires. In fact,

I don’t know what the cost of those was; I do know there was over

a quarter of a billion dollars spent just in fighting the wildfires

alone. And so that is one of the risks that goes along with the increases in drought and increases in heat waves.

Dr. MEEHL. Let me just add that the Southwest U.S. is actually

an area that we saw some interesting results when we looked the

model projections for extreme events, and you mentioned rainfall.

That’s an area that shows that when it does rain, in future projections, it rains harder, but there are actually more days in between

rainfall events. So the dry spells in between rainfall events increases, but when it does rain, it rains really hard. But when you

average those changes over a season, the average rainfall is still

less in the future projection. So in that area, in the Southwestern

U.S., is one area that is most consistent for this kind of result

where you just see a change in the nature of the precipitation, how

it falls, and how intense it is when it does rain.

REGIONAL VS. GLOBAL MODELING

Ms. GIFFORDS. Dr. Meehl, if I can follow up with you concerning

the difference between regional modeling and global modeling. Can

you talk a little bit about the regional models and how long it is

going to take them to catch up, globally?

98

Dr. MEEHL. Yes, there is whole class of models that we can

imbed, various high resolution regional models in the global models, so we have better representation of the mountain ranges and

things like that. This can be very important in regions where, like

in Colorado where I am from, where you have big mountains, or

in Arizona, you see the mountain ranges and where you get almost

locally specific rainfall regimes depending on how the mountain

ranges are. We can imbed these models in the global models and

get more information on smaller space scales. But those regional

models really depend on good global models to drive them. And it

is kind of the old garbage-in, garbage-out adage for computing. So

if your global model is bad, your regional model is not going to do

much better. But if the global model is improved it can drive the

imbedded regional model in a more credible way. So that is one of

the tools that we can use to get more regionally specific climatechange information, but it is still just a tool. It is not an end in

itself.

Chairman GORDON. The lady’s time has expired. I will say that

my grandfather used to tell me that the most important road in the

county is the one in front of your house. You have learned that lesson also.

Ms. GIFFORDS. And Mr. Chairman, can I just say that if every

kid growing up had Dr. Alley as a science teacher, we would have

more kids going into science because of your passions, so thank

you, Dr. Alley.

Chairman GORDON. So that is why we all want to sponsor and

be part of our competitiveness agenda. We are going to do that

with more scholarships for more science and math and physical

science teachers.

Again, the patient gentleman from Georgia, Mr. Gingrey, thank

you for sticking with us.

U.S. LEADERSHIP IN MITIGATING CLIMATE CHANGE

Mr. GINGREY. Mr. Chairman, thank you so much. It has not been

difficult sticking with you for almost three hours. I am, as you

know, returning to the Science Committee, and so it puts me down

in the bottom row.

But Dr. Alley, you had commented that those ice sheets are

sometimes—well, most of the time are boring and are occasionally

exciting, and I think you might could say the same thing about the

Science Committee, those of you have been here this morning. And

I think under Chairman Gordon’s leadership, it is going to be mostly exciting on the Science Committee. I agree with my colleague

who just said in complimenting Dr. Alley and the other panelists

who testified on the panel this morning. If you could take the tape

of this hearing and play it to the middle school class, I guarantee

there would be more young people going into science because this

has indeed been very exciting.

Chairman, I think you said there wasn’t a lot of good news here.

I would say that although it is pretty frightening, the global warming and the sea level and the ultimate outcome of what that might

be, well, the good news is it looks like God has given us a lot more

time than he gave Noah. Now, Dr. Solomon, that is not your

NOAA. That is N-o-a-h.

99

I wanted to point out, and it is been said by some of my colleagues, that a number of us, actually six on this committee, had

an opportunity to go to Antarctica, and that is because of the

Science Committee. And I was one of those six, I am very grateful.

And it was mentioned today, something, a policy, that when we

were on the ice, that we couldn’t use aerosols. I now know why. I

didn’t ask the questions, then. But this has been an outstanding

hearing. I am grateful to the panel. I am grateful for the Speaker.

It is an historic opportunity for the Speaker of House to come before the Committee and testify. I appreciate her comments, particularly in regard to nuclear power. I do have an answer for one of

her concerns and that is where would we store the waste? I would

suggest that maybe there is place out in Nevada called Yucca

Mountain, but that is an argument for another day.

I do have a question, believe it or not, and Dr. Meehl, I am going

to address it to you. There is going to be an upcoming article in

Newsweek magazine by George Will. We have talked about this,

and I know this is a question that you scientists maybe don’t want

to address and are maybe not necessarily the experts, and that is

for us to do, but basically this is what he says in this article ‘‘Inconvenient Kyoto Truth: the United States is able to drastically

regulate our manmade, greenhouse gas emissions,’’ 35 percent, as

was stated by Dr. Ehlers, ‘‘but other large industrial countries like

China, Israel and Brazil, do not.’’ Will the United States efforts

still achieve a positive effect? Take, for example, that China is set

to construct all of those new coal-powered plants by 2030, and they

have stated that they have no interest, they aren’t going to do anything to regulate their emissions. What will the United States’ restrictions do to stem the climate change trends that you outline in

the IPCC AR–4 report? And that is my question.

Dr. MEEHL. And again, I am going to have to apologize because

I am not an expert in this area, so I really can’t give you a good

answer for that.

Mr. GINGREY. Well, any one of the four would be grateful.

Dr. TRENBERTH. It will set a good example. I mean I think I

think it is a global problem, and U.S. leadership plays a key role,

and it does relate then to international pressures to bring everyone

in line, I think.

Mr. GINGREY. Anyone else? Dr. Trenberth, I think that is a darn

good answer, and I appreciate it, and I too have learned a lot here

today and changed my attitude. I began to change that attitude

when I went to the ice about a year ago, and that was a great opportunity. I thank you, Mr. Chairman, and I yield back.

Chairman GORDON. Thank you, Dr. Gingrey. In response to your

suggestion that we should be able to watch this for children, we

can. Compliments of the Science Committee, if you will go to

www.science.house.gov, you can get the web cast of this hearing,

the witnesses’ statements, Leader Pelosi’s statement, and the Chair

and Ranking Member’s statement, so that is, once again—get your

pencil—www.science.house.gov.

I was two out of three today, Mr. Gilchrest, on unanimous consent. The first unanimous consent was to allow you as a former

Member of this committee to sit in and ask questions, so we will

conclude with those statements or questions with you, sir.

100

MORE ON CLIMATE SCIENCE

Mr. GILCHREST. Thank you very much, Mr. Chairman. I am very

happy to see that none of my Republican colleagues objected to

that. I have been on the Science Committee a couple of times in

the past, and like many of my colleagues, I have been to the ice,

the dry valleys and the magnificent spots down there in the Antarctica, so maybe after this hearing, I might ask my side for a

waiver to get on the Science Committee again. It looks like it is

going to be a pretty exciting year.

I want to take a few seconds to talk about the economic impact

of pursuing a program to reduce greenhouse gases and what that

would do. To my colleagues remaining here, we have worked with

about a dozen Fortune 500 companies, including DuPont, General

Electric, Caterpillar, Lehman Brothers, and so on to work this

issue through. Their suggestion, their strong suggestion, is based

on the risk factor of investment of doing something and what could

happen economically if we don’t do something. Their suggestion is

that the Federal Government create a goal of reducing greenhouse

gases by the year 2050 by 70 percent below 1990 levels and then

set up a regulatory structure in which there is a cap-and-trade program and tax incentives. And they say through that structure, they

can meet that goal by the year 2050—not only meet that goal, but

excel at it based on propensity and ingenuity of the United States

technology and efficiency, and improve economic viability by improving situations as far as dependence on foreign oil is concerned

and a whole range of other things. So there is a pretty good structure out there to do that.

I have four questions that I would like to ask right up front in

case I run out of time. The first one is, you have mentioned, let us

say, 10,000 years ago that CO2 concentrations in the atmosphere

was about 180 parts per million. Fast forward about 10,000 years,

and you have it at 280 per million. And then you come up to the

present day, and it is about 380 parts per million. Now, the most

recent introduction of increases from a variety of sources is the

burning of fossil fuel. Like one of our colleagues said, we have put

in the atmosphere in just a few decades, that it took the natural

sources to lock up in the form of fossil fuel over millions of years.

Can you make a distinction between the kind of carbon that you

get from a volcano or other natural sources and the kind of carbon

that you get from burning fossil fuel? Is there a marker that you

can see, and do you use that in your equation to determine what

it man-induced and what not man-induced?

The second question is can you over, let us say, the last 20 years,

maybe the last 30 years, determine the cubic miles, the volume of

water, coming off the Greenland ices, and has that accelerated in

the last 20, 10, five years.

Chairman GORDON. In all due respect, let us see if we are going

to have time to get through those two before we go on any further.

Dr. SOLOMON. On the first one, if I may, the numbers you gave

were more or less right, except for the time scales. The time when

very much lower concentration of CO2 were observed is really quite

a bit earlier. You have to go back to, really, the ice ages.

Mr. GILCHREST. About 10,000 what were the concentrations?

101

Dr. SOLOMON. You have to go a little bit farther back, more like

20.

Mr. GILCHREST. 20,000, it was about 180 parts per million.

Dr. SOLOMON. And then when we came out of the Ice Age, it

went to about 270. As it said earlier, it stayed at 270 for almost

9.9 thousand years.

Mr. GILCHREST. Really, that is even more incredible.

Dr. SOLOMON. Yeah, you can see that in Figure 1. And then, in

the last 100, it went dramatically up to about 380, which is where

it is now, and it has not been at levels that high in at least 650,000

as Dr. Alley said.

Your question about a marker is also a very good one. As we

talked about earlier, the kind of carbon that you get when you burn

a fossil fuel is different in terms of its isotopes than what you get

from, you know, say trees or other sources of carbon. So the

changes in isotopes are a very key element in demonstrating the

human influence. Also, the north-south gradient, we see a difference between the northern hemisphere and the southern hemisphere which is also indicative of the human source in the northern

hemisphere.

Dr. ALLEY. And then for the Greenland ice sheet, we have

watched some of the glaciers speed up with satellite data and put

more icebergs into the ocean, and the Atmospheric Surface Mass

Balance Community has been reconstructing snowfall and melting

on the ice sheet and has seen a rise in snowfall but a faster rise

in melting so that it is losing mass that way. You also see that

from satellite.

Chairman GORDON. Excuse me. The gentleman’s time has expired. In respect to this committee, this panel has been here for

three hours. I know you have another briefing to go to and then

you have a hearing in the Senate. The Minority had more than due

notice to find someone to rebut you. They were not able to do that

either through the scientific community or through the Chamber of

Commerce. However, Mr. Rohrabacher has been very studious

these last three hours in preparing a rebuttal, and I think it is only

fair that we allow him that opportunity.

Mr. ROHRABACHER. Thank you much, Mr. Chairman. First, of all,

let me compliment you on putting together a fine panel of experts

for us, and I apologize for us in the Science Committee along with

the many scientists, who disagree with them and have honest disagreement on this issue. And in fact, I will be placing in the record

the names of hundreds of those scientists who disagree with this

concept that climate change is caused by human activities. Not

that there is climate change, but that it is caused by human activity. And we could have had any number of those scientists, and it

was remiss on our part not to have someone here representing a

scientific—there are people from MIT and Harvard and many,

many respected scientists who disagree with this theory. They

should have been here. It is our fault for not getting them here.

Let me compliment you as far as a good panel. I think it is great

that Speaker Pelosi was here, and I apologize if I do not believe

that the objection that was made reflects in any way the attitude

of the other Members of this committee, the Republican Members

of this committee. I thought it was fine that she spoke, and we paid

102

her the same respect that paid Newt Gingrich and others who have

spoken before this panel in the past.

With that said, I do have very serious disagreement with some

of the ideas presented today. And look, the reason I have to push

for an answer, and I shouldn’t have to actually ask five times before I get an answer on certain questions, that it is important to

know how much of the greenhouse gases that exist in our atmosphere were caused by natural occurrences. And that is an important thing because in terms of the weight that you put on the

changes that need to be made it makes all of the difference in the

world. A small change—and if you believe that, as I do, and I remember Dr. Bartlett, who is also a Ph.D. I might add, and has

many credentials on this, nor did he believe was 10 percent. Vern

Ehlers said 35. I have heard other science panels who really struggled to say that it was between five and ten percent. With that

noted, there is a huge disproportion of natural causes of greenhouse gas. Which means that a small change in the natural causes

of greenhouse gases, like volcanoes, would have a much bigger impact than a change of human activity, if we could, indeed, create

human-activity change on such a broad scale.

So scientists disagree. I am submitting for the record their

names. Also, let me note that many scientists are complaining that

their research money has been cut off because they disagreed with

global warming concepts, and I will be submitting their names for

the record as well.

But there is no doubt that global climate change is happening.

The only question is why is this cycle of global climate change, and

we have gone through dozen of cycles of global climate change, why

is it any different than all the other cycles? I noted during the testimony that was presented, the chart that shows that we are now

in a cycle when temperature is going up, that it started at the very

end of the mini Ice Age which was a very low point, where temperature had been declining for hundreds of years. So whether or

not how dramatic this change will be or what it is caused by, are

things that honest people, I think, can disagree with. And I really,

personally, having been a journalist, the first thing I was cautioned

by is when someone was claiming, ‘‘well everybody is on my side

or everybody says this or there is a total consensus.’’ Most always

when people said that to me during my years as a journalist, it

wasn’t true. It was that there were honest people who disagreed

and there was significant disagreement on such issues, and we

don’t know what those other cycles were caused by in the past. It

could be dinosaur flatulence or—who knows? But we do know the

CO2 in the past had its time when it was greater as well. And what

happened when the CO2 was greater than now? There is been

many cycles of up-and-down warming.

So with that said, I think that we have had a great discussion

today. We need this discussion because the idea, Mr. Chairman, of

having some sort of initiative so that our country creates new energy sources to make ourselves independent and making sure that

those energy sources are clean is a totally bipartisan goal. It is.

There is no doubt that all of us should want to make sure that

America isn’t held hostage to foreign energy sources and that when

we do develop new energy sources that they are clean. But the

103

question that comes to the heart of the matter is this—I am sorry

for pontificating too long in this—when we make that decision as

a Congress as to what those energy alternatives will be, we

shouldn’t be basing on science, if it is wrong science that suggests

that global climate change is as big an issue as human health. I

would prefer to make sure that when we are becoming energy independent and that we develop new energy sources, that we focus our

science on making sure that we take the bad stuff out of the atmosphere that hurts human beings, rather than the stuff that may or

may not create a cycle that would make us two or three degrees

warmer or less in the future.

So with that, I have had my say. I appreciate the privilege of

having a closing statement. I appreciate your leadership on this.

You held a great discussion today.

Chairman GORDON. Thank you, Mr. Rohrabacher. I hope you feel

better. I think the panel has addressed Mr. Rohrabacher’s concern

on a variety of occasions, so I won’t take your time any more, but

I do want to very sincerely thank you for the Herculean effort that

you put into this product and for allowing the United States Congress Science and Technology Committee to be your first forum

today

I think one of the lessons learned today is something that we all

should already know which is sometimes it is tough to be a messenger, but you have a very important message. We are glad you

came. The message that needs to go out from this hearing is that

113 nations concurred, including this country, that with 100 percent certainty, there is global warming and with 90 percent certainty it is a result, to a great extent, from human activities.

Thank you very much for being here, and all of the witnesses are

dismissed, and the meeting is adjourned.

[Whereupon, at 1:05 p.m., the Committee was adjourned.]

(105)

Appendix:

ANSWERS TO POST-HEARING QUESTIONS

106

ANSWERS TO POST-HEARING QUESTIONS

Responses by Susan Solomon, Co-Chair, IPCC, Working Group I: The Physical Basis

of Climate Change; Senior Scientist, Earth System Research Laboratory, Office

of Oceanic and Atmospheric Research, National Oceanic and Atmospheric Administration, U.S. Department of Commerce

Questions submitted by Representative Ralph M. Hall

Q1. How did you develop the Summary for Policy-makers? For example, did you ask

policy-makers what scientific information would be most useful to them and

structure the Summary around that information? If not, how did you determine

which findings to include in the Summary for Policy-makers?

A1. First and subsequent drafts of the Summary for Policy-makers (SPM) were prepared and revised by a sub-group of authors of the IPCC (2007) Working Group I

Report and reflect their joint selection of material that they felt should be presented

in order to best summarize the full report.

The list of those scientists is given on the front page of the Summary and includes

33 primary authors (collectively representing each of the 11 chapters of the full report), along with 18 contributing authors.

Drafts of the SPM were also discussed with the entire Working Group I author

team during author team meetings. All of the 152 authors of the full report were

also invited to provide written comments. Comments were also invited from over

600 experts who had reviewed the rest of the full report. Comments were also invited from governments. The SPM draft was revised by the listed subgroup of authors based upon their evaluation of all comments received.

In the course of the IPCC Working Group I Tenth Session held in Paris from January 29 to February 1, 2007, delegates from 113 countries approved the final SPM

on a line-by-line basis. Authors were present throughout this session and were

charged with ensuring that all proposed changes to wording in the SPM remained

fully consistent with the full report. During this final approval process the Lead Authors also identified a small number of changes to the underlying report that will

ensure consistency with the language used in the final SPM or provide additional

clarity for policy-makers on matters discussed during the session. None of these

changes alter the substantive findings of the report and the list of such changes was

made available from the IPCC Working Group I web site after the conclusion of the

WG I session (http://ipcc-wg1.ucar.edu/).

Q2. It is my understanding that in this IPCC report you associated terms such as

‘‘very likely’’ with numerical confidence levels such as ‘‘90 percent probability of

occurrence;’’ but that in previous IPCC reports you did not associate numerical

confidence levels with terms such as ‘‘very likely.’’ Why did you add in the numerical confidence levels in this IPCC report?

A2. Addressed in joint response.

107

ANSWERS TO POST-HEARING QUESTIONS

Responses jointly by Richard B. Alley, Lead Author, IPCC, Working Group I, Chapter

4: Observations: Changes in Snow, Ice and Frozen Ground; Evan Pugh Professor

of Geosciences and Associate of the Earth and Environmental Systems Institute,

Pennsylvania State University; Kevin E. Trenberth, Coordinating Lead Author,

IPCC, Working Group I, Chapter 3: Observations: Surface and Atmospheric Climate Change; Head, Climate Analysis Section, National Center for Atmospheric

Research; Gerald A. Meehl, Coordinating Lead Author, IPCC, Working Group I,

Chapter 10: Global Climate Projections; Senior Scientist, National Center for Atmospheric Research; and Susan Solomon, Co-Chair, IPCC, Working Group I:

The Physical Basis of Climate Change; Senior Scientist, Earth System Research

Laboratory, Office of Oceanic and Atmospheric Research, National Oceanic and

Atmospheric Administration, U.S. Department of Commerce

Question submitted by Representative Ralph M. Hall

Q1. It is my understanding that in this IPCC report you associated terms such as

‘‘very likely’’ with numerical confidence levels such as ‘‘90 percent probability of

occurrence;’’ but that in previous IPCC reports you did not associate numerical

confidence levels with terms such as ‘‘very likely.’’ Why did you add in the numerical confidence levels in this IPCC report?

A1. It is not the case that numerical confidence levels were introduced for the first

time in this report as suggested in the question. IPCC has carefully developed the

numerical confidence levels used, and they were also used in the previous IPCC report in 2001 (see footnote 7 of the 2001 Summary for Policy-makers, page 2 of the

report). The terms ‘‘likely’’ and ‘‘very likely’’ were used in the 2001 report where

each was deemed appropriate by the authors, and the terms ‘‘likely’’ and ‘‘very likely’’ are used in exactly the same way in the new IPCC (2007) report. This was introduced in the 2001 report to avoid the problem that the confidence, uncertainty and

likelihood of certain things can be interpreted differently by different readers of the

report, so a clearly defined scale aids communication and understanding.

Questions submitted by Representative Jo Bonner

Q1. A Wall Street Journal article dated Feb. 5, 2007 says that data from the U.S.

National Climate Data Center showed that in 2006 the world was only 0.03 degrees Celsius warmer than it was in 2001. This difference is in the range of

measurement error and is thus not statistically significant. This data might suggest that the world is not warming as fast as first thought. How do you respond

to this data report?

A1. These data do not indicate any weakness in scientific observations of warming

to date or projections of further temperature increase described in the Working

Group I report. Natural fluctuations associated with weather and phenomena like

El Nin ̃ o mean that warming trends are only reliably seen over decades, not year

to year. The recent history of temperature change includes a general warming trend,

most of which is very likely due to the increase in greenhouse gas concentrations,

overlaid with year-to-year variability arising from other features of the climate system. The effects of this short-term variability must be separated from the longerterm trend to allow estimation of the size of the trend; the comparison between single-year numbers for 2001 and 2006 does not do so, and so does not produce a scientifically valid estimation of the warming trend. Over the past 25 years the trend

is 0.18°C per decade, and the statistical uncertainty puts the value from 0.13 to

0.23°C per decade with 90 percent confidence.

Q2. A report published by the Center for Science and Public Policy and authored by

Lord Christopher Monckton shows that a 2001 U.N. assessment has over-estimated the human influence on climate change by at least one-third. Lord

Monckton also says that in a 2001 report the U.N. estimated that sea levels

would rise three feet by 2100, but in reality he notes that sea levels will rise only

seventeen inches. This is a big difference. What do you think this difference

shows?

A2. We presume that the reports referenced are the ‘‘IPCC Fourth Assessment Report 2007: Analysis and Summary’’ and the corresponding IPCC Third Assessment

Report from 2001. Further, we presume that the claimed ‘‘over-estimate’’ of human

influence refers to this statement in Lord Monckton’s document: ‘‘The U.N.’s 2001

report showed that our greenhouse gas emissions since 1750 had caused a ‘‘radiative

108

forcing’’ of 2.43 watts per square meter. Our other effects on climate were shown

as broadly self-canceling. In the current draft, the U.N. has cut its estimate of our

net effect on climate by more than a third, to 1.6 watts per square meter. It now

thinks pollutant particles reflecting sunlight back to space have a very strong cooling effect.’’

The values in the 2007 IPCC report actually are very consistent with and thus

increase confidence in those from the earlier IPCC report, and show that the previous report did not ‘‘over-estimate the human influence on climate change by at

least one-third.’’ Primarily because of continuing emissions, the best estimate of radiative forcing of long-lived greenhouse gases has increased from 2.43 watts per

square meter in the 2001 report to 2.64 watts per square meter in the 2007 report

(obtained by summing the central estimates of the effects from carbon dioxide,

methane, nitrous oxide and halocarbons from Table SPM–2 of the 2007 report, corresponding directly to the sum from the 2001 report). This long-lived greenhouse gas

forcing is not the total forcing, however, and the effects of ozone and the cooling effects of aerosols must be properly included. The 2001 report did discuss the aerosol

effects (in Lord Monckton’s words, the ‘‘cooling effect’’ of ‘‘pollutant particles’’), including direct effects on radiation and indirect effects through induced changes in

clouds, but the 2001 report noted that no best estimate could be given for some of

these effects owing to large uncertainties. The improved ability to include these effects in the 2007 report represents a scientific advance that more accurately quantifies the human effect on climate, and does not in any way represent a prior overestimate of human influence.

Regarding sea-level rise, the Summary for Policy-makers of the IPCC Fourth Assessment Report states (p. 14) that, if considered for the same time interval and

emission scenario, the midpoint of the projected sea-level rise from the Third Assessment Report is within 10 percent of that for the Fourth Assessment Report, and

that, had uncertainties been treated in the same way, the ranges in those projections would have been similar. Thus, there is not a big difference. Furthermore, as

noted in our response to Question 5, below, any additional contribution to sea-level

change from additional changes in the dynamical behavior of the large ice sheets

cannot be assessed accurately and was therefore omitted from the quantitative estimates.

Q3. Do you think that more emphasis needs to be placed on the population increases

in China and India and the vast migration from rural areas to cities? This increase creates demand for property and increases pollution in the cities. Why do

we not focus more on these areas to reduce pollution and stop what you consider

global warming?

A3. Our testimony concerned the findings of Working Group I of the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, on the physical

science basis of climate change. Impacts and adaptation will be considered by Working Group II, and mitigation by Working Group III. The question here goes beyond

the scope of our Working Group I report, and beyond our individual scientific expertise. However, different possible future population levels, patterns of development,

and energy sources and conversion technologies, among other factors, are considered

in the Special Report on Emissions Scenarios (SRES). The SRES scenarios in turn

underlie the projections of future climate change discussed in the Working Group

I report. The different scenarios, e.g., in Table SPM–2 and Figure SPM–7, therefore

provide considerable information on the importance of the factors mentioned in the

question.

Q4. A.R. Ravishankara with the National Oceanic and Atmospheric Administration

said that if you remove pollutants from the air that act as a cooling mechanism,

then the heating effect would be intensified. How do you suggest that we find

a medium to which pollutants could be reduced to an extent without harming

the cooling effect that they have?

A4. Dr. Ravishankara’s statement is fully consistent with the IPCC (2007) report.

For a given atmospheric concentration of anthropogenic greenhouse gases, lowering

the level of anthropogenic aerosols would produce an additional heating effect. (We

interpret ‘‘pollutants’’ in the question to refer to anthropogenic aerosols.) As a corollary to this, the ‘‘cooling’’ effect of current levels of aerosols can be seen in estimates of global-average radiative forcing. As shown in Figure SPM–2 of the Summary for Policy-makers of the Fourth Assessment Report of Working Group I of the

Intergovernmental Panel on Climate Change, there is a negative radiative forcing

from anthropogenic aerosols, partially offsetting the warming effect of anthropogenic

greenhouse gases.

109

The appropriate policy response to this observation is beyond the scope of our report, and beyond our individual scientific expertise. Climate science and the Working Group I Report can inform policy choices by describing how the climate will respond to given levels of aerosols and greenhouse gases. However, there is nothing

inherent to the Earth’s physical climate that prevents both anthropogenic aerosols

and anthropogenic greenhouse gases being reduced to whatever levels are deemed

societally desirable. For instance, by increasing energy efficiency and cutting down

on fossil fuel burning, both greenhouse gas and aerosol emissions could be reduced.

Q5. The U.N. Climate Panel estimates that Antarctica will actually increase its snow

mass this century. Would this not go against the argument that scientists are

making saying that glaciers and polar ice caps are melting as a result of global

warming?

A5. We presume that ‘‘The U.N. Climate Panel’’ refers to Working Group I of the

Intergovernmental Panel on Climate Change, in which we participated. Our report

notes that data show that mountain glaciers have declined on average in both hemispheres, and that losses from the ice sheets of Greenland and Antarctica have very

likely contributed to sea level rise over 1993 to 2003. The report states ‘‘Current

global model studies project that the Antarctic ice sheet will remain too cold for

widespread surface melting and is expected to gain in mass due to increased snowfall. However, net loss of ice mass could occur if dynamical ice discharge dominates

the ice sheet mass balance’’ (p. 17) and, with reference to the dynamical ice discharge, ‘‘understanding of these effects is too limited to assess their likelihood or

provide a best estimate or an upper bound for sea level rise.’’ (p. 17) Thus, increased

snowfall is expected in Antarctica, but the trend in overall mass of the ice sheet

(including loss by ice flow feeding iceberg calving) is not known. More generally, all

glaciers respond to the balance between accumulation of snow and loss by melting

or iceberg calving. With warming, the atmosphere can hold more water vapor and

thus precipitation is apt to increase. In some areas, a resulting increase in accumulation wins out. However, for most glaciers, in spite of increased accumulation, the

melt wins out, but this can vary enormously over short distances depending on the

local features.

110

(111)

THE STATE OF CLIMATE CHANGE SCIENCE

2007: THE FINDINGS OF THE FOURTH ASSESSMENT REPORT BY THE INTERGOVERNMENTAL PANEL ON CLIMATE CHANGE

(IPCC), WORKING GROUP II: CLIMATE

CHANGE IMPACTS, ADAPTATION AND VULNERABILITY

TUESDAY, APRIL 17, 2007

HOUSE OF REPRESENTATIVES,

COMMITTEE ON SCIENCE AND TECHNOLOGY,

Washington, DC.

The Committee met, pursuant to call, at 10:00 a.m., in Room

2318 of the Rayburn House Office Building, Hon. Bart Gordon

[Chairman of the Committee] presiding.

112

113

HEARING CHARTER

COMMITTEE ON SCIENCE AND TECHNOLOGY

U.S. HOUSE OF REPRESENTATIVES

The State of Climate Change Science 2007:

The Findings of the Fourth Assessment

Report by the Intergovernmental Panel on

Climate Change (IPCC), Working Group II:

Climate Change Impacts, Adaptation

and Vulnerability

TUESDAY, APRIL 17, 2007

10:00 A.M.–12:00 P.M. 2318 RAYBURN HOUSE OFFICE BUILDING

Purpose

On April 17, 2007, the Committee on Science and Technology will hold a hearing

on the second section of the 2007 Fourth Assessment Report, Climate Change 2007:

Climate Change Impacts, Adaptation and Vulnerability, prepared by Working Group

II of the Intergovernmental Panel on Climate Change (IPCC). Released in Brussels,

Belgium, on April 6, 2007, the summary document highlights the key findings of the

comprehensive appraisal of the current state of scientific knowledge on the impacts

of climate change on natural and human systems around the world. The full underlying report will be released later this year.

The Committee will hear testimony from six witnesses who were involved in the

preparation of the Working Group II Report. The witnesses will discuss the findings

of the report and the relationship between current findings and those of past IPCC

reports on the state of the science of climate change impacts, adaptation, and vulnerability.

Key Findings of the 2007 Working Group II Report

On April 6, 2007 the Intergovernmental Panel on Climate Change (IPCC) released

the second section of its Fourth Assessment Report, entitled ‘‘Climate Change Impacts, Adaptation and Vulnerability.’’ This second section of the IPCC Fourth Assessment Report builds upon information contained in the previous reports. Working

Group II was responsible for assessing the scientific, technical, environmental, economic and social aspects of the vulnerability to climate change of ecological systems,

socio-economic sectors and human health. The Working Group was co-chaired by Dr.

Osvaldo Canziani from Argentina and Dr. Martin Parry from the United Kingdom.

This report updates information from the Third Assessment Report based on research conducted over the past six years. Providing a comprehensive analysis of how

climate change is affecting natural and human systems, Working Group II’s report

also projects what the impacts of climate change will be in the future and assesses

the roles adaptation and mitigation can play in reducing these impacts. The report

also contains chapters on specific systems, sectors and regions.

Held from April 2nd through 6th, the 8th Plenary session of Working Group II

(WGII) gathered government delegates from more than one hundred countries, together with the WGII Lead Authors. The IPCC-produced documents, including this

Summary for Policy-makers (SPM), are consensus documents, meaning that all

member governments approve the Summary documents and the underlying chapters

before each document is released.

Observed Trends

The Fourth Assessment Report represents a significant expansion in our knowledge of the relationship between climate change and impacts on the planet. The

number of studies of observed trends in the physical and biological environment and

their relationship to regional climate changes has increased greatly since the Third

Assessment Report in 2001. This is the first time that WGII has sufficient information to attribute observed changes in physical and biological systems to human-inVerDate 11-MAY-2000 16:07 May 12, 2008 Jkt 032966 PO 00000 Frm 00003 Fmt 6601 Sfmt 6621 C:\WORKD\FULL07\020807\32966A.TXT SCIENCE1 PsN: SCIENCE1
114

duced global warming. Despite remaining uncertainties, WGII concluded that observational evidence from all continents and most oceans demonstrates that many natural systems are being affected by regional climate change, with regard to:

• Snow, ice and frozen ground: There is high confidence that natural systems are being affected through the enlargement and increased number of

glacial lakes, increasing ground instability, rock avalanches in mountain regions, and changes in Arctic and Antarctic ecosystems.

• Hydrological systems: There is high confidence of increased run-off and

earlier spring peak discharge in many glacier- and snow-fed rivers. In addition, studies assessed in this document show a warming of lakes and rivers

in many regions, with effects on thermal structure and water quality.

• Land biological systems: There is very high confidence that recent warming is causing earlier timing of spring events, such as leaf-unfolding, bird migration, and egg-laying, as well as poleward shifts in ranges of plant and animal species.

• Marine and freshwater biological systems: There is high confidence that

the impacts of climate change, including rising water temperatures, changes

in ice cover, salinity, and circulation, are causing shifts in ranges and changes

in algal, plankton, and fish abundance. In addition, climate change stressors

are linked to increases in algal and zooplankton abundance in high-latitude

and high-altitude lakes and changes in fish migration patterns in rivers.

Projections of Future Impacts

The report addresses projected future impacts in six different categories and for

eight regions.

Freshwater resources are projected to increase at high latitudes and in wet

tropical areas and decrease in dry areas in the mid-latitudes and in the dry tropics.

This is projected to increase the extent of drought-affected areas. In other areas,

heavy precipitation events are likely to increase in frequency resulting in an increase in flood risk. Water stored in glaciers and snow cover is projected to decline.

This will reduce water availability to one-sixth of the world’s population that relies

upon meltwater from major mountain ranges.

Projections for natural ecosystems are quite negative. The report concludes that

many ecosystems’ capacity to adapt to climate change in combination with the other

human-induced changes and natural disturbances will be overwhelmed during this

century. This is projected to lead to a decline in many systems and a substantial

loss of biodiversity and a reduction in ecosystem services (e.g., water and food supply). The uptake of carbon by terrestrial ecosystems is projected to peak before 2050

and then to weaken or possibly reverse. A reversal would amplify climate change

by adding more greenhouse gases to the atmosphere. Ocean acidification due to absorption of carbon dioxide from the atmosphere is expected to result in declines in

shell-forming organisms (e.g., corals) and the species that are dependent upon them.

Projections for food production (agriculture and fisheries) and forestry are mixed over time and for different regions. Global projections for crop productivity

indicates that it will increase slightly where local average temperature increases are

in the range of one to three degrees Centigrade, but will decline above this range.

Commercial timber production is projected to increase slightly in the short- to medium-term, but regional variations around this trend are substantial. Aquaculture

and fisheries are both expected to decline overall and the distributions and production of particular species will change regionally. Regional projections for crop productivity indicate increases at mid- to high latitudes for increases in the range of

one to three degrees Centigrade. These increases are sustained in some areas and

decline in others for further temperature increases. In the seasonally dry regions

and the dry tropics, crop productivity is projected to decline. In areas where frequency of droughts or floods is projected to increase, local crop productivity will be

lower. This is anticipated especially in areas of subsistence farming in the lower

latitudes. It is anticipated that agricultural systems will be the most amenable to

applying adaptive solutions to climate change through introduction of new cultivars,

alteration of water, fertilizer, and land management techniques.

Coastal systems and low-lying areas are projected to be exposed to increased

risks due to coastal erosion and rising sea level. The impacts will be exacerbated

by increasing human-induced changes in coastal areas. Adaptation options will be

variable with developing countries and small island states facing greater challenges

than developed countries. Coastal ecosystems, including wetlands and mangroves

115

will be negatively affected by sea level rise. Coral reefs are also projected to decline

due to increased bleaching and other stresses due to increased ocean water temperature. Millions more people are expected to experience flooding every year due to sea

level rise by late in this century. This is especially true for people living in the mega

deltas of Asia and Africa and people living in small island states.

The costs and benefits to industry, settlement and society will be highly variable for different locations and scales, but net effects are projected to be more negative with greater changes in climate. The most vulnerable areas will be coastal and

floodplain areas. Economic activities that are most closely associated with climatesensitive resources (e.g., water, fisheries, some agriculture) will be most vulnerable

to climate change. Areas where extreme weather events become more intense or

more frequent will experience increased economic and social costs due to each event.

Impacts on human health are projected to be primarily negative. While fewer

cold related deaths are projected to occur in high latitude areas, increased deaths

due to heat stress, floods, fires, and droughts will offset these and exceed them especially in the long-term if adaptive measures are not put into place. Malnutrition is

projected to increase in areas where food production will decline and the distribution

of infectious disease vectors is anticipated to change in response to changing climate

(e.g., mosquitoes and ticks). The balance between positive and negative health outcomes will vary considerably with implementation of adaptive measures through

public health prevention programs, infrastructure, health care, education, and economic development.

Regional Impacts

This report summarizes the impacts to specific continents and regions of the

world, including Africa, Asia, Australia and New Zealand, Europe, Latin America,

North America, polar regions, and small islands. For most of the regions of the

world, the projected impacts are negative.

Africa is projected to be one of the most vulnerable continents to climate variability and change. The combination of sea level rise in low-lying coastal areas, declining agricultural productivity across the region due to climate variability and

change, and increasing problems of water availability all are projected to create serious constraints for African nations.

Asia is projected to have crop yield increases in some regions (East and Southeast

Asia) and crop yield declines in others (Central and South Asia). Coastal areas, particularly the heavily-populated mega-deltas of South, East, and Southeast Asia will

be at increased risk due to sea level rise and in some cases due to flooding from

rivers. Glacier melt in the Himalayas is projected to increase flooding and risk of

rock avalanches from destabilized slopes. Once the glaciers have melted, water

shortages will be experienced by populations dependent upon glacier meltwater.

Water availability is also projected to be an increasing problem in Central, South,

East and Southeast Asia particularly in the large river basins.

Australia and New Zealand are projected to experience increasing water availability problems due to increased temperatures and reduced precipitation in many

areas. Some increases in agricultural productivity and forest productivity are projected for Western and Southern New Zealand. In Eastern New Zealand and in

much of Southern and Eastern Australia, agriculture and forestry production are

projected to decline due to drought and fire. The unique natural systems of this region are projected to decline significantly, including the Great Barrier Reef and

Queensland Wet Tropics.

Europe is projected to be negatively affected in nearly all regions. Impacts of current climate changes have been documented for the first time: retreating glaciers,

longer growing seasons, shift of species ranges and health impacts due to extended

severe heat waves. Negative impacts are projected to include increased risk of inland flash floods, more frequent coastal flooding and increased coastal erosion, continued glacier melting, reduced snow cover and extensive species loss. Many organisms and ecosystems will exceed their capacity to adapt to climate change. Northern Europe will generally fare better than Southern Europe through benefits such

as reduced heating costs, increased crop yields and increased forest growth with

modest increases in average temperature. Southern Europe will become more prone

to droughts and more frequent and intense heat waves. Wildfires and peat fires are

projected to increase.

By 2050 Latin America is projected to experience replacement of tropical forest

by dry savanna in eastern Amazonia and replacement of semi-arid vegetation with

arid vegetation as average temperatures increase and soil moisture decreases. There

116

is risk of substantial species loss throughout tropical Latin America. In drier areas,

climate change is expected to lead to salinisation and desertification of agricultural

land leading to reduced crop and livestock yields in these areas. In temperate areas,

soybean yields are projected to increase. Melting of glaciers in the Andes will impact

water availability for populations dependent upon meltwater. Sea level rise will increase flooding risks in low-lying coastal areas and increases in surface ocean temperatures are projected to have adverse effects on Mesoamerican coral reefs and related fisheries.

Polar regions are projected to experience reduced thickness of glaciers and extent of glaciers and ice sheets and reductions in permafrost and increases in the

depth of permafrost thawing in summer months. These physical changes are projected to have negative impacts on migratory birds and mammals. The reduction in

extent of sea ice and warmer temperatures provide benefits for ocean navigation

and reduced heating costs. However, coastal erosion and changes in permafrost will

impact infrastructure and request investments to adapt or re-locate some physical

structures and communities.

Small Island states are particularly vulnerable to reductions in precipitation and

sea level rise. Some of the Pacific atoll islands are only a few meters above sea level

currently. Sea level risk is projected to worsen the impacts of inundation, storm

surge, erosion and other coastal hazards which will put island populations at increased risk during storm events. Fisheries and tourism are projected to be negatively impacted as well. By 2050, many islands in the Pacific and Caribbean will

experience water shortages during low rainfall periods.

Below are the projected impacts of climate change for North America.

• There is very high confidence that warming in western mountains will lead

to decreased snow pack, more winter flooding and reduced summer flows, exacerbating competition for over-allocated water resources.

• Forests are projected to experience longer periods of high-fire risk, and greater increases in the area burned; they will also experience disturbances from

pests and diseases.

• Cities currently experiencing heat waves could expect them in greater frequency, intensity and duration over the century. The potential for adverse

health impacts grows, and the growing elderly population will be most at risk.

• Coastal communities and habitats will be increasingly stressed by climate

change impacts interacting with development and pollution. Losses are projected to increase if the intensity of tropical storms increases, as population

growth and rising value of infrastructure in coastal areas increase vulnerability to climate change. Readiness for increased exposure is low.

• Aggregate yields of rain-fed agriculture could increase by five to twenty percent because of moderate climate change in the early decades of the 21st century. Major challenges are projected for crops that are near the warm end of

their suitable range.

Responding to Climate Change

Since the IPCC Third Assessment there is growing evidence of human activity

adapting to observed and anticipated climate change. For example, climate change

is considered in the design of infrastructure projects such as coastal defense in the

Maldives and the Netherlands. In Nepal, preventative measures have been undertaken to stop outburst flooding of glacial lakes, and in Australia, substantial efforts

are underway to reduce water use and better manage this resource. According to

the report, these adaptive measures will be necessary to address climate change impacts as a certain degree of warming is unavoidable due to past emissions.

There are wide arrays of adaptation options available to policy-makers but barriers, limits and costs exist to these strategies reaching their potential. In addition,

the vulnerability of certain regions to climate change can be exacerbated by the

presence of other stressors such as pollution, poverty, food insecurity, conflict, and

incidence of disease. In contrast, sustainable development is discussed by Working

Group II as a possible way to reduce vulnerabilities to climate change.

We are committed to some change in climate over the next decade due to past

emissions of greenhouse gases and their long residence time in the atmosphere.

Even stringent mitigation policies enacted now will not prevent climate change impacts over the next few decades. If emissions of greenhouse gases continue

unabated, mitigation policies are necessary to avoid the most severe impacts of climate change. Adaptive measures can avoid some of the most serious impacts of climate change over the next few decades. However, they will not be sufficient to overVerDate 11-MAY-2000 16:07 May 12, 2008 Jkt 032966 PO 00000 Frm 00006 Fmt 6601 Sfmt 6621 C:\WORKD\FULL07\020807\32966A.TXT SCIENCE1 PsN: SCIENCE1
117

come the more serious impacts projected if mitigation actions are not taken. This

report suggests a response portfolio composed of multiple strategies including mitigation, adaptation, technological development, and research.

Many estimates of aggregate net economic costs of damages (i.e., the social cost

of carbon) from climate change are now available, expressed in terms of the future

net benefits and costs that are discounted to the present. Peer-reviewed estimates

of the social costs of carbon for 2005 have an average value of $12 per ton of carbon

dioxide with a range from $3 to $130 per ton. Furthermore, the impacts of climate

change will vary regionally but net costs are very likely to impose net annual costs

which will increase over time as global temperatures increase.

Witnesses

Dr. Virginia Burkett, U.S. Geological Society (USGS) Global Change Science Coordinator

Dr. Virginia Burkett served as a Lead Author for Chapter 6 of the report entitled:

Coastal Systems and Low Lying Areas. Currently, Dr. Burkett is serves as a USGS

Global Change Science Coordinator at the National Wetlands Research Center. She

completed her undergraduate and Master’s degrees in biology at Northwestern State

University and obtained her Ph.D. in forestry in 1996 from Stephen F. Austin State

University in Nacogdoches, Texas. Dr. Burkett’s current research involves climate

change impacts in coastal regions and bottomland hardwood regeneration in frequently flooded sites of the Mississippi River Alluvial Floodplain.

Dr. William E. Easterling, Director of the Pennsylvania State University Institutes

of the Environment

Dr. William Easterling served as a Coordinating Lead Author for Chapter 5 of the

report entitled: Food, Fibre and Forest Products. Currently, Dr. Easterling is the Director of the Pennsylvania State University Institutes of the Environment, as well

as a Professor in the Geography Department at the university. Dr. Easterling received his training as an economic geographer and climatologist at the University

of North Carolina at Chapel Hill. His current research focuses on the potential for

agriculture in developed and developing countries to adapt to climate variability and

change. In addition, Dr. Easterling looks at issues such as the role of scale in understanding the vulnerability of complex systems, especially agro-ecosystems, to environmental change.

Dr. Roger Pulwarty, Research Associate at National Oceanic and Atmospheric Administration’s (NOAA) Climate Diagnostics Center

Dr. Roger Pulwarty served as a Lead Author for Chapter 17 of the report entitled:

Assessment of Adaptation Practices, Options, Constraints and Capacity. Dr.

Pulwarty is a research scientist at the NOAA–CIRES Climate Diagnostics Center

in Boulder, Colorado. Dr. Pulwarty’s research interests include climate and weather,

their role in society-environment interactions, and the design of effective services to

address associated risks. His research and applications focus on natural resources

policy, development and decision-making in the Western U.S., Latin America, and

the Caribbean.

Dr. Cynthia Rosenzweig, Senior Research Scientist at NASA Goddard Institute for

Space Studies

Dr. Cynthia Rosenzweig served as a Coordinating Lead Author for Chapter 1 of

the report entitled: Assessment of Observed Chanced and Responses in Natural and

Managed Systems. Dr. Rosenzweig is a Senior Research Scientist at NASA Goddard

Institute for Space Studies where she heads the Climate Impacts Group. She has

organized and led large-scale interdisciplinary regional, national, and international

studies of climate change impacts and adaptation. In addition, she serves as an Adjunct Professor in the Department of Environmental Science at Barnard. A recipient

of a Guggenheim Fellowship, she has joined impact models with global and regional

climate models to predict future outcomes of both land-based and urban systems

under altered climate conditions.

Dr. Stephen H. Schneider, Co-Director of the Center for Environmental Science and

Policy (CESP) and the Interdisciplinary Program in Environment and Resources

(IPER) at Stanford University

Dr. Stephen H. Schneider served as a Coordinating Lead Author for Chapter 19:

Assessing Key Vulnerabilities and the Risk from Climate Change. Currently, Dr.

Schneider is a Professor in the Department of Biological Sciences and Co-Director

of the Center for Environmental Science and Policy (CESP) and the Interdisciplinary Program in Environment and Resources (IPER) at Stanford University. His

global change research interests include: climatic change; global warming; food/cliVerDate 11-MAY-2000 16:07 May 12, 2008 Jkt 032966 PO 00000 Frm 00007 Fmt 6601 Sfmt 6621 C:\WORKD\FULL07\020807\32966A.TXT SCIENCE1 PsN: SCIENCE1
118

mate and other environmental/science public policy issues; ecological and economic

implications of climatic change; integrated assessment of global change; climatic

modeling of paleoclimates and of human impacts on climate, e.g., carbon dioxide

‘‘greenhouse effect’’ or environmental consequences of nuclear war. He is also interested in advancing public understanding of science and in improving formal environmental education in primary and secondary schools. Dr. Schneider received his

Ph.D. in Mechanical Engineering and Plasma Physics from Columbia University in

1971.

Dr. Shardul Agrawala, Visiting Research Scholar in the Program in Science, Technology and Environmental Policy at Princeton University

Dr. Shardul Agrawala served as a coordinating lead author for Chapter 17 of the

report: Assessment of Adaptation Practices, Options, Constraints, and Capacity. Dr.

Agrawala is the Administrator for Climate Change, Environmental Directorate, Organization for Economic Co-operation and Development (OECD) in Paris, France. In

addition, he is a Visiting Research Scholar with the Program in Science, Technology

and Environmental Policy at the Woodrow Wilson School of Public and International

Affairs, Princeton University. Dr. Agrawala received his Ph.D. from the Woodrow

Wilson School of Public and International Affairs in 1999.

119

Chairman GORDON. Good morning. We have with us today six

distinguished scientists who authored chapters of the second part

of the Intergovernmental Panel on Climate Change Report that

was released in Brussels on April 6. We know you have been on

a whirlwind tour and we appreciate you coming and joining us

today.

This second report moves beyond the fact that global warming is

occurring to provide us with a picture of what global warming

means for natural systems and human communities throughout the

world. For the near-term, the picture is a mosaic of positive and

negative impacts. Some areas are now experiencing changes that

have put them at greater risk from drought, avalanches, floods and

fires. For others, there are benefits in the form of lower heating

costs, fewer deaths due to cold exposure, lengthening growing seasons and increases in crop yield.

Even our national security would be impacted by the effect of climate change. Recently the Pentagon released a study entitled ‘‘The

National Security and the Threat of Climate Change’’ which looks

at possible security problems including mass migrations, increased

border tensions, greater demands for rescue and evacuation efforts,

and conflicts over essential resources including food and water. In

the long-term, negative impacts begin to overtake the positive impacts.

If we do not reduce emissions of greenhouse gases, our children

and our grandchildren will face considerable challenges due to climate change in the latter half of this century. In the near-term, it

appears we can implement strategies to cope with climate change

impacts. We must start to adapt because the climate is changing

and will continue to change even if we reduce emissions tomorrow.

Adaptation will help our generation to cope with climate change.

However, only mitigation will avoid and delay severe climate

change impacts our children and grandchildren are projected to

case.

I do not want to leave my daughter and her generation with the

burden of a world with more food shortages, extended droughts,

displaced coastal communities, increased public health problems

and political instability created by increased numbers of people displaced by climate-driven changes in their environment.

The information brought to us in this report makes a compelling

case for action. We need to make our communities more climate resistant. Adaptation is an essential near-term step to reduce vulnerability to climate change but adaptation alone is not enough. We

owe it to our children and our future generations to lead the world

in a global effort to reduce greenhouse gas emissions.

I thank our witnesses for appearing before us today and I also

thank you for your service to the IPCC. I look forward to hearing

your testimony.

[The prepared statement of Chairman Gordon follows:]

PREPARED STATEMENT OF CHAIRMAN BART GORDON

Good morning. Today we have six distinguished scientists who authored chapters

of the second part of the Intergovernmental Panel on Climate Change’s (IPCC) report that was released in Brussels on April 6.

120

This second report moves beyond the fact that global warming is occurring to provide us with a picture of what global warming means for natural systems and

human communities throughout the world.

For the near-term, the picture is a mosaic of positive and negative impacts. Some

areas are now experiencing changes that have put them at greater risk from

drought, avalanches, floods, and fires.

For others there are benefits in the form of lower heating costs, fewer deaths due

to cold exposure, lengthening growing seasons, and increases in crop yields.

Even our national security could be impacted by the effects of climate change.

Just yesterday, the Center for Naval Analysis released a study entitled, ‘‘National

Security and the Threat of Climate Change,’’ which looks at possible security problems including mass migrations, increased border tensions, greater demands for rescue and evacuation efforts, and conflicts over essential resources—including food

and water.

In the long-term, negative impacts begin to overtake the positive impacts. If we

do not reduce emissions of greenhouse gases our children and grandchildren will

face considerable challenges due to climate change in the latter half of this century.

In the near-term it appears we can implement strategies to cope with climate

change impacts. We must start to adapt because the climate is changing and will

continue to change even if we reduce emissions tomorrow.

Adaptation will help our generation to cope with climate change. However, only

mitigation will avoid and delay severe climate change impacts our children and

grandchildren are projected to face.

I do not want to leave my daughter and her generation with the burden of a world

with greater food shortages, extended droughts, displaced coastal communities, increased public health problems, and political instability created by people displaced

through climate-driven changes in their environments.

The information brought to us in this report makes a compelling case for action.

We need to make our communities more climate resilient. Adaptation is an essential near-term step to reduce vulnerability to climate change.

But adaptation alone is not enough. We owe it to our children and all future generations to lead the world in a global effort to reduce greenhouse gas emissions.

I thank our witnesses for appearing before the Committee today. Thank you also

for your service on the IPCC. I look forward to hearing your testimony.

Chairman GORDON. At this time I am pleased to yield to distinguished Ranking Member, Mr. Hall, for an opening statement.

Mr. HALL. Mr. Chairman, good morning. I am glad that our good

Chairman organized this hearing about the important topic of climate change impacts, adaptation and vulnerability, and let me

start by thanking all of the witnesses for being here today. Climate

change is becoming a very key issue in the 110th Congress and we

all appreciate your time and the scientific expertise that you can

provide for our consideration.

Climate change is one of our nation’s biggest challenges but so

too are the equally important challenges of energy independence

and affordability. Our nation needs solutions that address all of

these issues and they need to be mutually exclusive goals. We can

and should develop affordable energy solutions that reduce our carbon intensity while freeing our nation from the grip of foreign energy.

The scientific findings of this second IPCC working group will

prompt much debate about what policies the United States should

enact to address the potential impacts of climate change. The findings in the Working Group II’s reports have even more uncertainty

than those in the Working Group I report we heard about back in

February. Some in Congress are proposing bills that would create

a mandatory regulatory scheme to address carbon emissions. In

considering these pieces of legislation, we must also, and always,

weigh the cost and the benefits along with the unintended consequences that could result. The scientists at our hearing today can

tell us their best analysis of what climate effects to expect at cerVerDate 11-MAY-2000 16:07 May 12, 2008 Jkt 032966 PO 00000 Frm 00010 Fmt 6601 Sfmt 6601 C:\WORKD\FULL07\020807\32966A.TXT SCIENCE1 PsN: SCIENCE1
121

tain temperatures but they can’t answer the policy issues posed

above.

One issue that most of us agree on is that our country will experience impacts from climate change and we need to be ready to

adapt to them. I have faith in American innovation and finding solutions to help us adapt to these changes. Last year I authored the

National Integrated Drought Information System Act that authorized a program to improve drought forecasting and allow localities

to better manage their water resources. Adaptation will be important, and I look forward to hearing from these experts as they explain their findings in this key area.

In the long run, the key to addressing climate change will be

clean, affordable, and reliable energy technologies. We need much

more discussion in Congress on how new technologies can help

America become energy-independent and create a world with cleaner energy sources. There is a concentrated effort by a minority of

the environmental community to declare war on energy and to declare war on growth in general, and a war on fossil fuels specifically. They need to realize that if China offers $1 a barrel of oil

more than the U.S. now pays Saudi Arabia, we could overnight lose

60 percent of the energy we have from, guess what, fossil fuels. Let

us not be ridiculous about our energy needs simply to give some

politician or some editor a plaque for their walls.

I yield back my time.

[The prepared statement of Mr. Hall follows:]

PREPARED STATEMENT OF REPRESENTATIVE RALPH M. HALL

Good morning. I am glad the Chairman organized this hearing about the important topic of climate change impacts, adaptation and vulnerability. Let me start by

thanking all of the witnesses for being here today. Climate change is becoming a

key issue in the 110th Congress and we all appreciate your time and the scientific

expertise that you can provide to inform our policy discussions.

Climate change is one of our nation’s biggest challenges, but so too are the equally

important challenges of energy independence and affordability. Our nation needs solutions that address all of these issues, and they need not be mutually exclusive

goals. We can, and should, develop affordable energy solutions that reduce our carbon intensity while freeing our nation from the grip of foreign energy.

The scientific findings of this second IPCC working group will prompt much debate about what policies the United States should enact to address the potential impacts of climate change.

The findings in Working Group II’s report have even more uncertainty than those

in the Working Group I report we heard about in February. Some in Congress are

proposing bills that would create a mandatory regulatory scheme to address carbon

emissions. In considering these pieces of legislation, we must always weigh the cost

and benefits and the unintended consequences that could result.

The scientists at our hearing today can tell us their best analysis of what climate

effects to expect at certain temperatures, but they cannot answer the policy issues

posed above.

One issue that most of us agree on is that our country will experience impacts

from climate change and we need to be ready to adapt to them. I have faith in

American innovation in finding solutions to help us adapt to theses changes. Last

year, I authored the National Integrated Drought Information System Act that authorized a program to improve drought forecasting and allow localities to better

manage their water resources. Adaptation will be important and I look forward to

hearing from these experts today as they explain their findings in this key area.

In the long run, the key to addressing climate change will be clean, affordable,

and reliable energy technologies. We need much more discussion in Congress on

how new technologies can help America become energy independent and create a

world with cleaner energy sources.

I look forward to hearing from our witnesses today and yield back the balance

of my time.

122

Chairman GORDON. Thank you, Mr. Hall, and I think there are

lots of areas within your statement that we have consensus on and

I look forward to working with you.

If there are Members who wish to submit additional opening

statements, your statements will be added to the record.

[The prepared statement of Mr. Costello follows:]

PREPARED STATEMENT OF REPRESENTATIVE JERRY F. COSTELLO

Good morning. I want to thank Chairman Gordon for holding today’s hearing on

the second section of the 2007 Fourth Assessment Report, Climate Change 2007:

Climate Change Impacts, Adaptation and Vulnerability, prepared by Working Group

II of the Intergovernmental Panel on Climate Change (IPCC). The report examines

the current state of scientific knowledge on the impacts of climate change on natural

and human systems around the world. A large amount of progress has been made

in understanding and projecting the effects of future climate change since the previous IPCC report.

This report gives the Congress added information on global warming, and as we

begin to craft legislation. This process needs to be one of consensus, taking a wide

view of our current energy realities as well as the goals we need to reach in the

future. Toward this end, we cannot ignore the reality that coal is going to play a

role in our nation’s energy supply and the world energy supply for years to come.

Coal generates half of the electricity in this country and is a reliable domestic

source of power with a 250-year supply of coal in the U.S. alone. To fully maximize

our use of coal, we must continue to take steps that reduce emissions. The only way

to achieve this goal is through advancements in technology. I have been a strong

supporter of clean coal initiatives and programs to advance the research and development needed to improve coal-based electricity generation. Congress must continue

to support the clean coal programs in the President’s FY08 budget, which includes

the FutureGen Project, slated to be the world’s first zero-emissions coal plant.

Among other things, FutureGen will demonstrate the ability to sequester carbon dioxide emissions safely underground. The more coal plants using clean coal technology equals reduced greenhouse gas emissions.

Clean coal technologies do exist; however, they need the support and backing from

Congress to further develop and demonstrate their commercial viability. As we consider climate change legislation, I encourage my colleagues to include coal as part

of our energy solution. Again, I look forward to working with my colleagues as we

find practical solutions that lead us down the path of energy independence and protection of our environment.

I welcome the panel of witnesses and look forward to their testimony.

[The prepared statement of Mr. Lampson follows:]

PREPARED STATEMENT OF REPRESENTATIVE NICK LAMPSON

Good morning. Thank you Chairman Gordon for holding a hearing on this important report on the current and future impacts of climate change.

For some time now we have gambled with the future of our children and grandchildren. We have acted as if the early projections of climate change offered by the

scientific community were very unlikely—as if global warming was not occurring,

or that our actions had no effect on Earth’s climate system.

Over the past decade, however, the scientific evidence and consensus on climate

change has grown stronger. The new IPCC report and the one released earlier this

year make it clear that if we continue to avoid addressing global warming, future

generations will bear the burden of these negative climate change consequences.

This report is a call to action. We must identify key risks and vulnerabilities for

both human and natural systems. We must develop and implement adaptation

strategies to reduce the identified risks and vulnerabilities. To buy more time and

secure a better future, we must develop and implement mitigation strategies to

bring greenhouse gas emissions under control. It is the only way to avoid the severe

negative impacts projected to occur later this century.

In my home State of Texas we are too well-acquainted with the devastating effects

of severe weather events on individuals, communities, and the economy. Extended

droughts, tornadoes, and hurricanes are devastating for families who experience

them and extremely expensive for the Federal, State, and local governments that

must respond to and cope with them. If we succeed in reducing our vulnerability

to these events, we will not only reduce the monetary costs of confronting these

123

events, we will also avoid the human stress, suffering, and loss associated with

them.

I realize some changes we must make will be difficult. This effort will require significant investment and sacrifices on all our parts. But it is better to undertake

changes and direct them with foresight and planning than to have them forced upon

us in crisis situations. Let’s get to work on securing safe, climate-resilient communities here at home and abroad.

I want to thank all our witnesses for appearing before the Committee this morning and for contributing their time and talents to producing this important report.

[The prepared statement of Mr. Mitchell follows:]

PREPARED STATEMENT OF REPRESENTATIVE HARRY E. MITCHELL

Thank you, Mr. Chairman.

In February, we heard from some of the world’s top scientists about the growing

threat of global warming who reported to this committee some of the important findings of the International Panel on Climate Change (IPCC).

I think many of us were concerned about what they had to say, and troubled by

the scientific data that demonstrates the threat of global warming and climate

change isn’t simply a threat—it’s happening all across the world.

The findings of the IPCC Working Group II further demonstrate that climate

change’s footprint is clearly everywhere.

Water allocation is a pressing issue for Arizona and, according to the working

group’s most recent report, it will only get worse.

According to a recent article in the Seattle Times, scientists analyzing Working

Group II’s data found that the driest periods of the last century such as the Dust

Bowl of the 1930’s could become the norm for Southwest U.S. within decades. The

greatest effects will be felt along the U.S.-Mexico border and, climate researchers

predict, by 2100, rainfall will decline by 10 to 20 percent annually.

I look forward to learning more about Working Group II’s findings today. Understanding the regional affects and human vulnerabilities to the coming changes in

climate are essential to adequately adapt to and diminish the effects of this change.

I yield back the balance of my time.

[The prepared statement of Mr. Ehlers follows:]

PREPARED STATEMENT OF REPRESENTATIVE VERNON J. EHLERS

I am pleased that the Science and Technology Committee is hearing from scientists who participated in the second Working Group of the Intergovernmental

Panel on Climate Change (IPCC). I understand that preparing this report is an exhaustive, very diplomatic process and I commend these scientists for their willingness to work in arenas that may not be as comfortable as their home institutions.

Both our country, and the rest of the world, benefit from your sustained commitment to sharing quality scientific information.

It is disheartening to read this report and understand that even immediate actions to curb greenhouse gas emissions will not be able to stop near-term impacts

of climate change. We are past the point of acknowledging that this is a real issue

and have moved forward to the discussion of adaptation strategies. Based on this

most recent report, it is clear that some regions of the globe will benefit from global

warming. In fact, U.S. agriculture may actually see an increased growing season

and consequent productivity. But at some point even regions that initially benefit

will also succumb to secondary effects such as water shortages. As part of curing

our climate problem, we must recognize that those who benefit in the short-term

from warming trends may have less motivation to take actions to reduce greenhouse

gas emissions. Yet we must have an allied effort of both science and diplomacy

working hand-in-hand to achieve significant reductions.

In order to address climate change we must identify the problem, determine the

causes, and propose and adopt appropriate solutions. We recently heard from Working Group I of the IPCC, which concluded with high certainty that scientific research shows we have a problem, and that humans are one major cause behind the

problem. Working Group II addressed the impacts of climate change and will help

us make initial steps to adapt to changes in our environment. While adapting to

the changes is pragmatic, it is not a comprehensive solution.

I realize that today we are only concentrating on one facet of a most complicated

problem. The additional working groups of the IPCC also will help address the

broader policy questions of climate change strategy, and I look forward to reviewing

those results as well.

124

I thank the witnesses for being here today, and look forward to the opportunity

to hear what they have to say.

Chairman GORDON. At this time I would like to introduce our

witnesses. First, Dr. Cynthia Rosenzweig was the Coordinating

Lead Author of Chapter 1, Assessment of Observed Changes and

Responses in the Natural and Managed Systems of the Working

Group II Reports on Impacts, Adaptation and Vulnerably. Currently, Dr. Rosenzweig is a senior research scientist at NASA Goddard Institute for Space Studies, where she heads up the Climate

Impact Group. Welcome.

Our next witness will be Dr. William Easterling, who served as

Coordinating Lead Author for Chapter 5, Food, Fibre and Forest

Products. Dr. Easterling is the Director of Pennsylvania State University Institutes of the Environment and as of July 1 will become

Dean of the College of Earth and Mineral Sciences at Penn State.

Dr. Roger Pulwarty was the Lead Author of Chapter 17, Assessment of Adaptation Practices, Opinions and Constraints and Capacity. Currently, Dr. Pulwarty is a physical scientist at the NOAA

Climate Diagnostic Center in Boulder, Colorado. And Dr. Stephen

Schneider is Professor of Interdisciplinary Environmental Studies,

Biological Sciences and Civil Environmental Engineering and CoDirector of the Center for Environmental Science and Policy and

Interdisciplinary Program and Environment and Resources at

Stanford University. Dr. Schneider served as the Coordinating

Lead Author for Chapter 19, Assessing Key Vulnerabilities and the

Risk from Climate Change.

And I know Mr. Melancon would like to be here, I think he is

on his way, because he has a constituent in Dr. Virginia Burkett,

who is the Lead Author of Chapter 6, Coastal Systems and LowLying Areas, and USGS global change science coordinator at the

National Wetlands Research Center. So when Mr. Melancon comes

here, we will say nice things about you, Dr. Burkett.

We do thank you for coming. You have been on a whirlwind. I

know this has been a very tough few years getting ready for this.

I know some of our previous authors in Working Group I said it

was the most really physically, intellectually demanding thing they

have been through and so we appreciate your work and we welcome you here.

Well, Mr. Hall had to take testimony at another hearing and we

are glad that Dr. Ehlers is here for introduction of the final witness. Okay, he is not. Well, let us see. Does the Minority have a

witness here? Yes. I am going to let you help me. Do you want to

go forward?

Mr. EHLERS. Sorry about the confusion but Mr. Hall had to leave

for an urgent meeting. I am very pleased to introduce Mr. Shardul

Agrawala. Thank you very much for participating here in this particular event, and I might add that I admire all of you for your

willingness to depart the comfort of your individual offices scattered around the country and to participate in this exhausting and

exhaustive work that you have done, and I deeply appreciate it.

With that, I will return it to the Chairman.

Chairman GORDON. Thank you, Dr. Ehlers.

The previous Chairman, Sherwood Boehlert, used to say that although witnesses are supposed to complete their testimony in five

125

minutes, that 300 seconds on a very important issue like we have

today is a little bit confining. So we have your regular testimony

so we hope you will summarize but we don’t want you to feel under

great constraints when the red button comes, but we would like to

get home tonight.

Dr. Rosenzweig, we will yield to you.

STATEMENT OF DR. CYNTHIA ROSENZWEIG, SENIOR RESEARCH SCIENTIST, NASA GODDARD INSTITUTE FOR SPACE

STUDIES, THE EARTH INSTITUTE AT COLUMBIA UNIVERSITY

Dr. ROSENZWEIG. Thank you, Mr. Chairman. My testimony comes

from Section B of the Working Group II contribution to the Intergovernmental Panel on Climate Change, which is called the Climate Change 2007 Climate Change Impacts, Adaptation and Vulnerability. This is from the approved summary for policy-makers.

This part of the summary concerns the relationship between observed climate changes and recent observed changes in natural and

human environments. The statements presented here are based

largely on data sets that cover the period since 1970. The number

of studies of observed trends in the physical and biological environment and their relationship to regional climate changes has increased greatly since the Third Assessment in 2001. The map

shows the temperature rises since 1970 and the data series of

changes in physical and biological systems that were assessed in

the chapter.

From the current assessment, we conclude that observational

evidence from all continents and most oceans shows that many natural systems are being affected by regional climate changes, particularly temperature increases. With regard to changes in snow,

ice and frozen ground including permafrost, examples are enlargement and increased numbers of glacial lakes, increasing ground instability in permafrost regions and rock avalanches in mountain regions. There are also changes in some Arctic and Antarctic ecosystems including those in sea ice biomes and also predators high

in the food chain; among them, polar bears.

The following types of hydrological systems are being affected

around the world: increased runoff and earlier spring peak discharge in many glacier and snow-fed rivers and warming of lakes

and rivers in many regions with effects on thermal structure and

water quality. Recent warming is also strongly affecting terrestrial

biological systems such as earlier timing of spring events. Examples are leaf unfolding and blooming, bird migration and egg laying, and pole-ward and upward shifts in ranges in plant and animal species.

There is also substantial new evidence about observed changes in

marine and freshwater biological systems. These include shifts in

ranges and changes in algal, plankton and fish abundance in highlatitude oceans, increases in algal and zooplankton abundance in

high-latitude and high-altitude lakes, range changes and earlier

migrations of fish in rivers.

The changes I just described were responding at the regional

scale. In Chapter 1, what we also did was do a global assessment

looking at all of the changes, assessing all the changes together.

Here we find that a global assessment of data since 1970 has

126

1See Endbox 2.

shown it is likely that anthropogenic warming has had a discernible influence on many physical and biological systems. There are

four sets of evidence which taken together support this conclusion.

The first is coming from our colleagues in Working Group I, who

concluded that most of the observed increase in the globally average temperature since the mid-20th century is very likely due to

the observed increase in anthropogenic greenhouse gas concentrations.

The second line of evidence is of the more than 29,000 observational data series, there are dots representing 29,000 data series

from 75 studies that show significant change in many physical and

biological systems. More than 89 percent are consistent with a direction of change exhibited as a response of warming.

The third line of evidence is that of a global synthesis of studies

in this assessment strongly demonstrates that the spatial agreement between the regions of significant warming across the globe

and the locations of the significant observed changes in the natural

systems consistent with warming is very unlikely to be due solely

to natural variability of the temperatures nor of the systems themselves.

Finally, there have been several modeling studies that have

linked responses in some physical and biological systems to anthropogenic warming.

Consistency between the observed and model changes in several

studies and the spatial agreement between significant regional

warming and consistent impacts at the global scale is sufficient to

conclude with high confidence that anthropogenic warming over the

last three decades has had a discernible influence on many physical

and biological systems.

Thank you, Mr. Chairman.

[The prepared statement of Dr. Rosenzweig follows:]

PREPARED STATEMENT OF CYNTHIA ROSENZWEIG

Dr. Cynthia Rosenzweig is entering into testimony Section B of the Working

Group II Contribution to the Intergovernmental Panel on Climate Change, Climate

Change 2007: Climate Change Impacts, Adaptation and Vulnerability Approved

Summary for Policy-makers.

Current knowledge about observed impacts of climate change on the natural and human environment

A full consideration of observed climate change is provided in the IPCC Working

Group I Fourth Assessment. This part of the Summary concerns the relationship between observed climate change and recent observed changes in the natural and

human environment.

The statements presented here are based largely on data sets that cover the period since 1970. The number of studies of observed trends in the physical and biological environment and their relationship to regional climate changes has increased

greatly since the Third Assessment in 2001. The quality of the data sets has also

improved. There is, however, a notable lack of geographic balance in data and literature on observed changes, with marked scarcity in developing countries.

These studies have allowed a broader and more confident assessment of the relationship between observed warming and impacts than was made in the Third Assessment. That Assessment concluded that ‘‘there is high confidence1 that recent regional changes in temperature have had discernible impacts on many physical and

biological systems.’’

From the current Assessment we conclude the following.

127

2See IPCC Working Group I Fourth Assessment Report Summary for Policy-makers.

3Measured by the Normalised Difference Vegetation Index, which is a relative measure of the

amount of green vegetation in an area based on satellite images. 4See Endbox 2.

5 A subset of about 29,000 data series was selected from about 80,000 data series from 577

studies. These met the following criteria: (1) Ending in 1990 or later; (2) spanning a period of

Continued

Observational evidence from all continents and most oceans shows that

many natural systems are being affected by regional climate changes, particularly temperature increases.

With regard to changes in snow, ice and frozen ground (including permafrost) 2, there is high confidence that natural systems are affected. Examples are:

• enlargement and increased numbers of glacial lakes [1.3];

• increasing ground instability in permafrost regions, and rock avalanches in

mountain regions [1.3];

• changes in some Arctic and Antarctic ecosystems, including those in sea-ice

biomes, and also predators high in the food chain [1.3, 4.4, 15.4].

Based on growing evidence, there is high confidence that the following types of

hydrological systems are being affected around the world:

• increased run-off and earlier spring peak discharge in many glacier- and

snow-fed rivers [1.3];

• warming of lakes and rivers in many regions, with effects on thermal structure and water quality [1.3].

There is very high confidence, based on more evidence from a wider range of species, that recent warming is strongly affecting terrestrial biological systems, including such changes as:

• earlier timing of spring events, such as leaf-unfolding, bird migration and

egg-laying [1.3];

• poleward and upward shifts in ranges in plant and animal species [1.3, 8.2,

14.2].

Based on satellite observations since the early 1980s, there is high confidence that

there has been a trend in many regions towards earlier ‘greening’ 3 of vegetation in

the spring linked to longer thermal growing seasons due to recent warming. [1.3,

14.2]

There is high confidence, based on substantial new evidence, that observed

changes in marine and freshwater biological systems are associated with rising

water temperatures, as well as related changes in ice cover, salinity, oxygen levels

and circulation [1.3]. These include:

• shifts in ranges and changes in algal, plankton and fish abundance in highlatitude oceans [1.3];

• increases in algal and zooplankton abundance in high-latitude and high-altitude lakes [1.3];

• range changes and earlier migrations of fish in rivers [1.3].

The uptake of anthropogenic carbon since 1750 has led to the ocean becoming

more acidic with an average decrease in pH of 0.1 units [IPCC Working Group I

Fourth Assessment]. However, the effects of observed ocean acidification on the marine biosphere are as yet undocumented. [1.3]

A global assessment of data since 1970 has shown it is likely4 that anthropogenic warming has had a discernible influence on many physical and biological systems.

Much more evidence has accumulated over the past five years to indicate that

changes in many physical and biological systems are linked to anthropogenic warming. There are four sets of evidence which, taken together, support this conclusion:

1. The Working Group I Fourth Assessment concluded that most of the observed increase in the globally averaged temperature since the mid-20th century is very likely due to the observed increase in anthropogenic greenhouse

gas concentrations.

2. Of the more than 29,000 observational data series5, from 75 studies, that

show significant change in many physical and biological systems, more than

128

at least 20 years; and (3) showing a significant change in either direction, as assessed in individual studies.

89 percent are consistent with the direction of change expected as a response

to warming. (Figure SPM–1) [1.4]

3. A global synthesis of studies in this Assessment strongly demonstrates that

the spatial agreement between regions of significant warming across the

globe and the locations of significant observed changes in many systems consistent with warming is very unlikely to be due solely to natural variability

of temperatures or natural variability of the systems. (see Figure SPM–1)

[1.4]

4. Finally, there have been several modelling studies that have linked responses in some physical and biological systems to anthropogenic warming

by comparing observed responses in these systems with modelled responses

in which the natural forcings (solar activity and volcanoes) and anthropogenic forcings (greenhouse gases and aerosols) are explicitly separated. Models with combined natural and anthropogenic forcings simulate observed responses significantly better than models with natural forcing only. [1.4]

Limitations and gaps prevent more complete attribution of the causes of observed

system responses to anthropogenic warming. First, the available analyses are limited in the number of systems and locations considered. Second, natural temperature variability is larger at the regional than the global scale, thus affecting identification of changes due to external forcing. Finally, at the regional scale other factors (such as land-use change, pollution, and invasive species) are influential. [1.4]

Nevertheless, the consistency between observed and modelled changes in several

studies and the spatial agreement between significant regional warming and consistent impacts at the global scale is sufficient to conclude with high confidence that

anthropogenic warming over the last three decades has had a discernible influence

on many physical and biological systems. [1.4]

Other effects of regional climate changes on natural and human environments are emerging, although many are difficult to discern due to adaptation and non-climatic drivers.

Effects of temperature increases have been documented in the following systems

(medium confidence):

• effects on agricultural and forestry management at Northern Hemisphere

higher latitudes, such as earlier spring planting of crops, and alterations in

disturbance regimes of forests due to fires and pests [1.3];

• some aspects of human health, such as heat-related mortality in Europe, infectious disease vectors in some areas, and allergenic pollen in Northern

Hemisphere high and mid-latitudes [1.3, 8.2, 8.ES];

• some human activities in the Arctic (e.g., hunting and travel over snow and

ice) and in lower elevation alpine areas (such as mountain sports). [1.3]

Recent climate changes and climate variations are beginning to have effects on

many other natural and human systems. However, based on the published literature, the impacts have not yet become established trends. Examples include:

• Settlements in mountain regions are at enhanced risk to glacier lake outburst

floods caused by melting glaciers. Governmental institutions in some places

have begun to respond by building dams and drainage works. [1.3]

• In the Sahelian region of Africa, warmer and drier conditions have led to a

reduced length of growing season with detrimental effects on crops. In southern Africa, longer dry seasons and more uncertain rainfall are prompting adaptation measures. [1.3]

• Sea-level rise and human development are together contributing to losses of

coastal wetlands and mangroves and increasing damage from coastal flooding

in many areas. [1.3]

129

Figure SPM–1. Locations of significant changes in observations of physical systems

(snow, ice and frozen ground; hydrology; and coastal processes) and biological systems (terrestrial, marine, and freshwater biological systems), are shown together

with surface air temperature changes over the period 1970–2004. A subset of about

29,000 data series was selected from about 80,000 data series from 577 studies.

These met the following criteria: (1) Ending in 1990 or later; (2) spanning a period

of at least 20 years; and (3) showing a significant change in either direction, as assessed in individual studies. These data series are from about 75 studies (of which

?70 are new since the Third Assessment) and contain about 29,000 data series, of

which about 28,000 are from European studies. White areas do not contain sufficient observational climate data to estimate a temperature trend. The 2 x 2 boxes

show the total number of data series with significant changes (top row) and the percentage of those consistent with warming (bottom row) for (i) continental regions:

North America (NAM), Latin America (LA), Europe (EUR), Africa (AFR), Asia

(AS), Australia and New Zealand (ANZ), and Polar Regions (PR) and (ii) globalscale: Terrestrial (TER), Marine and Freshwater (MFW), and Global (GLO). The

numbers of studies from the seven regional boxes (NAM, . . ., PR) do not add

up to the global (GLO) totals because numbers from regions except Polar do not

include the numbers related to Marine and Freshwater (MFR) systems. [F1.8,

F1.9; Working Group I Fourth Assessment F3.9b]

130

BIOGRAPHY FOR CYNTHIA ROSENZWEIG

Dr. Cynthia Rosenzweig is a Senior Research Scientist at the NASA Goddard Institute for Space Studies located at Columbia University. Her primary research involves the development of interdisciplinary methodologies by which to assess the potential impacts of and adaptations to global environmental change. Recognizing that

the complex interactions engendered by global environmental change can best be

understood by coordinated teams of experts, Dr. Rosenzweig has organized and led

large-scale interdisciplinary, national, and international studies of climate change

impacts and adaptation. She co-led the Metropolitan East Coast Regional Assessment of the U.S. National Assessment of the Potential Consequences of Climate

Variability and Change, sponsored by the U.S. Global Change Research Program.

She is a recipient of the Guggenheim Fellowship and is a Fellow of both the American Association for the Advancement of Science and the American Society of Agronomy. She leads the Climate Impacts Research Group at the Goddard Institute of

Space Studies, whose mission is to investigate the interactions of climate variability

and change on systems and sectors important to human well-being. For the Fourth

Assessment Report (AR4) of the Intergovernmental Panel on Climate Change

(IPCC), she is the Co-Coordinating Lead Author for Chapter One, Assessment of Observed Changes and Responses in Natural and Managed Systems, of Working Group

II on Impacts, Adaptation, and Vulnerability.

Chairman GORDON. Thank you, Dr. Rosenzweig.

And now, Dr. William Easterling is recognized for five minutes.

STATEMENT OF DR. WILLIAM E. EASTERLING, PROFESSOR OF

GEOGRAPHY AND AGRONOMY; DIRECTOR, PENN STATE INSTITUTES OF ENERGY AND THE ENVIRONMENT, PENNSYLVANIA STATE UNIVERSITY

Dr. EASTERLING. Good morning, Chairman Gordon and distinguished Members of the Committee and ladies and gentlemen, I

am Bill Easterling, and since I was introduced, I will dispense with

a lot of background information and just get straight to the point.

I think that one of the great human achievements of the 20th

century was the progress that the world’s farmers made in increasing global food production in step with the increase in demand for

food. Even though hunger certainly persists everywhere in the

world, there is no question that the farmers have been successful

in generating the calories that we need to feed the plant, and the

question before us, and this was one of the central questions we

asked in the IPCC report on food and fibre and forestry was, can

this continue in the future under climate change.

Let me begin by saying that a large amount of progress has been

made since the last IPCC report in understanding and projecting

131

the effects of future climate change on agricultural production, although to be sure, significant uncertainties remain. It can now be

stated with higher confidence than before that climate change is

likely to challenge food security among the world’s poorest people,

particularly in countries in the low latitudes, in the tropics. Most

of the crops are grown there under conditions that are near the top

of those crops’ optimal temperature range and any warming at all

pushes them over the top and yields begin to fall.

Now, my first slide although it is difficult to see I know from

where you are but it is a snapshot and I will walk you through it,

tells the story with a series of graphs that show the synthesis of

nearly 70 recent modeling studies that have been divided between

the temperature mid to high latitudes and the tropical low latitudes. On these graphs, the cereal crop maize or, as we know it,

corn, wheat and rice yields which those by the way three cereals

make up about 75 to 80 percent of the total calories either consumed by us as humans or by livestock as feed, are shown as percentages of current yields versus increasing mean temperature. We

thought to be an effective way of summarizing what we have

learned about the effects of warming on crop yields. Many of these

studies were performed with and without adaptation assumptions

and the adaptations might be changes in planting times and

cultivar selections, commonsensical adaptations that farmers would

probably engage on their own. The red dots and lines are results

without adaptation and the green dots and lines are with adaptation, so notice that the red lines for the tropics show yields in all

three crops dropping below current levels after little more than one

degree Celsius of warming.

132

Now, the warming will be less troublesome, according to our

analysis, to agricultural systems in the mid to high latitudes like

the U.S., at least in the early stages of the warming, and notice the

red lines for the temperate mid- to high-latitude crops remain

above the current yields for the first few degrees of warming before

they begin to tail off. The green lines indicate that adaptation effectively keeps the temperate cereal crops near or above current yields

through moderate amounts of warming, say about four to five degrees Celsius of warming, but it only protects low-latitude tropical

crops for a few degrees, maybe about three degrees of warming. All

of the studies in these graphs include the beneficial effect of rising

atmospheric CO2, or carbon dioxide, levels on crop growth. This is

the so-called CO2 fertilization effect. There has been recent controversy over the strength of the CO2 fertilization effect with some

scientists feeling that we have tended to overestimate the strength.

This would imply that our global estimates of climate change damages to food production from previous studies are too low. Their arguments, scientists who are questioning the CO2 effect, are based

on the most recent and realistic field experiments to date.

The second slide gives you a visual snapshot of the old and new

experimental approaches and the old approach is the chamber experimental approach that is on the left side. It is not—it is a very

artificial environment versus the newer free-air carbon enrichment

rings out in fields where the CO2 is actually applied in measured

ways to simulate a much more realistic environment. Our assessment, after careful comparison of the older experimental results

with the new ones, is that the effects are not enough different to

warrant concern.

133

Our third slide shows how we reached this conclusion. It shows

wheat yields as percentages of current yields versus different levels

of atmospheric CO2 for both the old and the new experiments.

While there are too many experiment data points to plot them all,

it would make this look like a bowl of spaghetti, these data points

are fully contained within the blue shaded range on the graph. The

red line describes the general trend of the old experiments and the

three data points for the new experiments are plotted as red triangles at 550 parts per million CO2. Looking at it this way shows

that the new results are well within the range of the old results,

and the green oval on the graph brings it to your attention. Hence,

our conclusion is that the existing estimates of CO2 effects on food

supply under climate change would appear to be valid.

My final point, and Mr. Chairman, I can summarize this in just

a matter of a minute or two, is that a growing preponderance of

studies show that if the climate changes are accompanied by increasing climate variability, droughts and floods and extreme

events like those, crop yield losses are likely to occur at even smaller mean temperature increases than if variability is unchanged. So

the numbers I showed you before might look a bit different if variability changes appreciably from our current experience. For example, one study computed that under scenarios of increased heavy

precipitation, production losses due to excessive soil moisture

would double in the U.S. by 2030.

Those are among the more important findings of our chapter,

and I thank you for your attention and would be happy to answer

questions at the appropriate time.

[The prepared statement of Dr. Easterling follows:]

134

1 Any opinions, findings, conclusions, or recommendations expressed in this publication are

those of the author and do not necessarily reflect those of The Pennsylvania State University,

the Intergovernmental Panel on Climate Change, or other organizations.

PREPARED STATEMENT OF WILLIAM E. EASTERLING1

Introduction

My name is Bill Easterling. I am Professor of Geography and Agronomy at Penn

State University and Director of the Penn State Institutes of Energy and the Environment. I have authored over 70 refereed scientific publications in the areas of food

and climate, which are cited extensively, and I have given hundreds of presentations

concerning my areas of expertise. My research interests focus especially on the simulation of agricultural adaptation to climate change. I have been a member of many

national and international committees, including chairing the National Research

Council’s Panel on the Human Dimensions of Seasonal-to-Inter-annual Climate Variability. I have contributed to the efforts of the Intergovernmental Panel on Climate

Change (IPCC) in several ways, and serve as a Convening Lead Author on Chapter

5 (Food, Fibre, Forestry, and Fisheries), and on the Technical Summary and the

Summary for Policy-makers of Working Group II of the Fourth Assessment Report.

The Food and Climate Challenge

The global expansion of the world’s food supply in lock-step with growing world

food demand is one of humanity’s great achievements of the 20th and first years

of the 21st centuries. Hunger surely persists in nearly every country today, but not

because of shortage in the world’s supply of food calories. By the latter third of this

century, the world’s farmers will be challenged to feed as many as 10–12 billion people who are likely to be, in the main, wealthier and more demanding in their food

tastes than today. There are reasons to be optimistic that this challenge can be met

in a future world that co-evolves with a stable climate, although emerging issues

such as rising demand for bioenergy from crops could greatly increase pressures on

food production. This overall challenge and any additional pressures will, in the

long-run, be exacerbated by climate change.

As my colleague, Dr. Cynthia Rosenzweig notes in her testimony, the effects of

recent climate variability and change on agriculture are being observed now in the

form of longer growing seasons and faster temperature-regulated plant growth, especially in North America and Europe. As climate change intensifies in the future,

so are those and many other agricultural effects expected to intensify. The newly

released IPCC Working Group II report reaffirms a growing consensus among literally hundreds of field-based experiments and model-based simulation studies that

rising atmospheric carbon dioxide concentration, hereafter [CO2], and climate

change will provide temporary benefits in some regions and for some crops and immediate loss in other regions and crops. In particular, our chapter documents regional trends that point to major crop yield loss in the low latitudes, where a majority of the poorest people in the world live, and temporary crop yield gains in the

mid- to high latitudes.

I wish to speak to three major sets of findings concerning the potential consequences of future climate change for agricultural production at world and regional

levels. They are: 1) the distribution of possible crop yield winners and losers across

the Earth and the potential of adaptation to mediate that distribution; 2) the potential for rising [CO2] to offset climate change-induced crop yield loss (or enhance yield

gains); and 3) the effects of change in climate variability versus slow, steady climate

change on crops. In addressing those points, I will rely on the recent IPCC Working

Group II report exclusively.

Large regional variation in climate change effects on cereal crop productivity

Yield projections for the cereals maize (corn), wheat, and rice from nearly 70 studies that used physiologically-based plant simulation models are shown in Figure 1

below. The yield projections are expressed as percentage changes due to climate

change with respect to current observed mean yields. Results are divided into ‘‘without adaptation’’ and ‘‘with adaptation’’ cases as discussed below. In the ‘‘without adaptation’’ case, model experiments were performed with the assumption that farmers take no action to respond to climate change. Without adaptation, the models

broadly agree that, in mid- to high latitude regions (including North America), moderate to medium local increases in mean annual temperature (+1–3 C), along with

associated [CO2] increase and precipitation changes, can have small beneficial impacts on crop yields (see Figure 1 below). Those increases are the result of longer

135

growing seasons together with generally rising precipitation across many major

grain belts.

Similar projections in low latitudes (tropics and parts of subtropics) indicate falling cereal yields with even moderate annual temperature increase (+1–2 C) and associated [CO2] increase. Cereal crops in low latitudes are currently grown at temperatures near the peak of their optimum photosynthetic range; any warming at all

pushes crops past the edge of that range into sub-optimal photosynthetic temperatures, hence yield loss.

Mean global temperature increases beyond approximately +3 C result in a downturn of cereal yields in the mid- to high latitudes, with some exceptions (e.g., northern North America, northern Europe). This yield decrease occurs because of higher

heat stress combined with increased evapotranspiration that begins to dry soils in

spite of higher precipitation. Further warming has increasingly negative impacts on

cereal yields globally. Decreasing yields globally eventually are expected to slow

growth in agricultural production relative to growth in agricultural demand.

In the ‘‘with adaptation’’ case, model experiments in these same 70 studies were

performed with the assumption that farmers take action by changing planting dates

in order to accommodate earlier spring warm-up and cultivar selection for the longer

growing seasons under climate change. The ‘‘with adaptation’’ results indicate that

some of the yield loss reported above can be offset, again, depending on location.

In the mid- to high latitudes, as shown in Figure 1, adaptation allows cereal yields

to be maintained at or above current levels beyond ∼+5 C, but only up to ∼+3 C

in the low latitudes, depending on the crop. Beyond ∼+3 C in the low latitudes, adaptation is no longer effective for cereals.

Potential for rising [CO2] to offset climate change-induced crop yield loss

(or enhance yield gains)

Higher [CO2] levels increase photosynthesis and water use efficiency in most

plants, with certain crops (C3 species such as wheat, rice, soybeans) showing greater

response than other crops (C4 species such as corn, sorghum). Recent experimental

studies based on realistic field conditions indicate that, at 550 ppm CO2 (CO2 levels

are currently at approximately 380 ppm) yields increase under unstressed conditions by 10–25 percent for C3 crops, and by 0–10 percent for C4 crops, consistent

with previous IPCC estimates. Based on these recent studies, some researchers have

argued that crop response to elevated CO2 may be lower than previously thought,

with consequences for crop model projections of yields and food supply. The basis

for their argument is that the [CO2] effects in current crop models are derived from

earlier, less realistic experiments that tended to exhibit higher [CO2] sensitivity of

the crops than the recent studies. However, other researchers have carefully compared the results of the two experimental approaches and find that these new experimental findings are in fact consistent with previous. In addition, simulations of

unstressed plant growth and yield response to elevated CO2 in the main crop simulation models have been shown to be in line with recent experimental data, projecting crop yield increases of about 5–20 percent at 550 ppm CO2. These findings

reaffirm the validity of earlier projections of crop productivity and food production.

It is worth pointing out, however, that current crop models do not have adequate

internal structures for representing the effects of pests, disease, and certain extreme

weather events (hail, hurricanes and other flooding), all of which lower the confidence in their projections.

A change in climate variability is worse for crops than slow, gradual climate change

Climate change is most likely to become evident to farmers not by gradual change

in climate conditions, but rather by changes in the frequencies of damaging extremes such as droughts, excessive rainfall, and heat stress. Recent studies indicate

that climate changes that include increased frequency of heat stress and droughts

reduce crop yields and livestock productivity beyond the impacts due to changes in

mean variables alone, creating the possibility for surprises. A number of simulation

studies performed since the previous IPCC report have examined specific aspects of

increased climate variability within climate change scenarios. For example, one

study computed that, under scenarios of increased heavy precipitation, production

losses due to excessive soil moisture would double in the U.S. by 2030. More frequent extreme events may lower long-term yields by directly damaging crops at specific developmental stages, such as temperature thresholds during flowering, or by

making the timing of field applications more difficult, thus reducing the efficiency

of farm inputs.

136

Synopsis

A large amount of progress has been made in understanding and projecting the

effects of future climate change on agricultural production since the previous IPCC

report, although significant uncertainties remain. It can now be stated with higher

confidence than before that climate change is likely to challenge food security among

the world’s poorest people located in the low latitudes. It will be less troublesome

to agricultural systems in the mid- to high latitude nations (like the USA), at least

in the early stages of warming. Adaptation effectively maintains cereal yields in the

mid- to high latitudes at or above current levels through moderate amounts of

warming (∼+4–5 C), but it only protects low latitude cereal yields for a few degrees

of warming (∼+3 C). The direct effects of rising atmospheric CO2 levels on crop

growth will offset some of the deleterious effects and enhance the beneficial effects

of climate change. However, adaptation apart, low latitude cereal yields are projected to fall below current levels with modest warming, in spite of the beneficial

effects of rising CO2. In the mid- to high latitudes, CO2 offsets yield loss for a while,

but after ∼+3 C of global mean warming yields of the major cereal crops decline

below current levels, again assuming no adaptation. If the climate changes are accompanied by increasing climate variability and frequencies of extreme events, crop

yield losses are likely to occur at even smaller mean temperature increases than if

variability is unchanged.

137

BIOGRAPHY FOR WILLIAM E. EASTERLING

Dr. William E. Easterling is the Director of the Penn State Institutes of Energy

and the Environment and Professor of Geography and Earth System Science. On

July 1, 2007 he will become Dean of the College of Earth and Mineral Sciences at

Penn State. He received his Ph.D. in Geography and Climatology from the University of North Carolina at Chapel Hill and has held posts at Resources for the Future, and the University of Nebraska’s Department of Agricultural Meteorology. He

is an internationally known expert on global climate change focusing particularly

138

on the implications for agricultural production, food security and related global environmental change. Dr. Easterling is the convening lead author for the chapter on

food, forestry, and fisheries in the upcoming Intergovernmental Panel on Climate

Change Fourth Assessment Report. He has served on and chaired numerous committees and advisory groups for the National Oceanic and Atmospheric Administration, NASA, the National Science Foundation, and the National Research Council.

His responsibilities with the Institutes of the Environment are to increase the visibility and integration of Penn State’s environmental science and engineering by the

hiring of new faculty positions and the fostering of interdisciplinary research, education and outreach. Dr. Easterling is helping coordinate a new energy research initiative at Penn State focusing on connections between transportation, energy, and

the environment.

Chairman GORDON. Thank you, Dr. Easterling.

Dr. Burkett, you are recognized for five minutes.

STATEMENT OF DR. VIRGINIA BURKETT, CHIEF SCIENTIST

FOR GLOBAL CHANGE RESEARCH, U.S. GEOLOGICAL SURVEY, U.S. DEPARTMENT OF THE INTERIOR

Dr. BURKETT. My name is Virginia Burkett and it is a pleasure

to be here, Mr. Chairman and Committee. I am a scientist with the

U.S. Geological Survey and one of eight co-authors of the coastal

chapter. My co-authors are listed here from many countries.

The key policy-relevant findings in the coastal chapter are number one, that coasts are already experiencing the adverse consequences of climate-related hazards and sea-level rise. Number

two, coasts will be exposed to increasing risk over the coming decades as sea level rises and the climate changes. Number three, the

impact of climate change on coasts is exacerbated by increased

human development activity which we found to have a greater impact on coasts during the past century than did climate change.

Four, adaptation of coasts for developing countries will be more

challenging than for developed nations simply due to constraints on

adaptive capacity, whether technological, financial or institutional.

Five, adaptation costs are much less generally than the cost of inaction, and finally, the unavoidability of sea-level rise conflicts with

present-day human development patterns and trends.

139

140

We examined potential effects of climate change on all major

types of coastal systems ranging from coastal wetlands to coral

reefs to sea grasses to barrier islands and coastal forests and the

top line of this graphic shows the six major drivers of change, the

first on the left being increase in tropical storm intensity and wave

regime, accelerated sea-level rise, increased temperature, increased

CO2 concentrations and finally, changes in runoff which are due to

changes in precipitation and also due to the increase in temperature which causes a faster evaporation of surface waters. Each of

these climate-related processes plays an important role in structuring coastal systems but all coastal systems are not equally vulnerable. A wetland in one place is not the same as a wetland in

another place in terms of its vulnerability.

141

142

This slide lists some of the key vulnerabilities of coastal systems

in America. Our chapter dealt with all of the world of course but

these are some things I pulled out from one of our tables. For example there are over 1,000 U.S.-protected islands in the Pacific,

143

many of which have a mean elevation of three to 10 feet above sea

level. Sea-level rise will affect the water supply of many of these

islands a long time before the population is flooded. Shifting closer

to the mainland at Dauphin Island, Alabama, here is one of our

LiDAR (Light Detection And Ranging) images from our St. Pete

lab. The little green things with the tops that are red, those are

houses. You can see the Gulf of Mexico on the left and the Mississippi Sound and you can see the road going down the island

prior to Hurricane Ivan. The impacts of Hurricane Ivan on this island and Hurricane Katrina provide a good illustration of how the

predicted increase in hurricane intensity might affect low-lying

coastal barriers of the Southeast along the Gulf of Mexico and the

Atlantic border.

The IPCC report contains a cross-chapter study of mega deltas,

which are among the most vulnerable regions to climate change in

the world. Human societies in Asian mega deltas are considered

most vulnerable because of their exposure to risk, high population

concentration and lack of adaptive capacity. In North America, the

Mississippi River delta is the best example and it is ranked as

highly vulnerable in our chapter. In the subsiding Mississippi

delta, even minor changes in the rate of sea-level rise will have serious impacts on coastal wetlands and barrier islands which protect

the city of New Orleans, for example. Everything in red and yellow

on this slide was converted to open water during the past 70 years,

and if you look at the landfall of Hurricane Katrina, you can see

it in yellow there and you can see the land loss in the New Orleans

area just overnight in addition to what was shown on the earlier

side, and that is what the Chandeleur Island chain looks like now.

The left is before the storm and to the right is after the storm.

And here it looks like the flipside, like you just turned the Louisiana land loss map upside down and it is land loss in coastal

Alaska where the land is sinking, the permafrost is thawing. It is

70 percent ice, the substrate is there. The sea ice has retreated and

so the erosion of wave attack along that coast has accelerated and

it looks like it has accelerated, and this is just 50 years of land

change. There are substantial investments in infrastructure here

like the National Petroleum Reserve in Alaska. This well here was

drilled in 1970s. You can see how the land has collapsed under it

and the erosion has affected the shore face, and in addition to the

infrastructure there, there are many native communities that will

have to move.

[The prepared statement of Dr. Burkett follows:]

PREPARED STATEMENT OF VIRGINIA BURKETT

Mr. Chairman and Members of the Committee, as a Lead Author of the Fourth

Assessment Report by the Intergovernmental Panel on Climate Change (IPCC),

Working Group II, I am pleased to present a summary of the findings found in

Chapter 6, ‘‘Coastal Systems and Low-Lying Areas,’’ of the report. First, I want to

acknowledge my co-authors, with whom I have collaborated over the past three

years to develop this assessment of climate change impacts, adaptation and vulnerability in coastal systems:

Robert J. Nicholls (UK), Poh Poh Wong (Singapore), Jorge Codignotto (Argentina), John Hay (New Zealand), Roger McLean (Australia), Sachooda

Ragoonaden (Mauritius), and Colin D. Woodroffe (Australia)

Dr. Nichols and Dr. Wong served as Convening Lead Authors for the coastal chapter.

144

I deeply appreciate being nominated by the United States Government to serve

as a Lead Author of the Fourth Assessment Report, as well as the prior assessment

report published by the IPCC in 2001. The charge to the authors of the Fourth Assessment Report by the IPCC was to develop a balanced, comprehensive and policyrelevant assessment of current knowledge, which:

— evaluates the full range of knowledge (e.g., positive and negative effects),

— is policy-relevant, not prescriptive,

— is supported by clear evidence,

— is clear about underlying assumptions, and confidence levels,

— emphasizes new knowledge since the IPCC’s Third Assessment Report,

— is more concise than the Third Assessment Report, with better connections

to Working Groups I and III, and with wider use on non-English sources of

knowledge,

— and is lucidly written.

The IPCC Working Group II contribution to the Fourth Assessment Report was

guided by a complex, open and peer-reviewed process that engaged several hundred

authors and roughly 50 review editors from 47 countries; and well over 800 expert

reviewers. The coastal chapter authors responded to roughly 1,500 comments received during external peer and government reviews, and many of these comments

led us to additional new literature about coasts and climate change. I estimate that

our coastal chapter writing team reviewed between 500 and 700 scientific journal

articles, books and scientific proceedings published since 2000.

For each chapter of the IPCC report, two or three Review Editors were selected

by the IPCC from the lists of experts nominated by the governments. The three Review Editors assigned to the coastal chapter were: Job Dronkers (Netherlands),

Geoff Love (Australia), and Jin-Eong Ong (Malaysia). The main duty of these scientists was to ensure that we responded appropriately to comments on our draft

chapter from experts and the governments during two separate cycles of review.

With each review the scope of the material contained in the chapter expanded and

the consensus of the authors emerged fairly easily in our case as we identified the

key drivers and their impacts.

Please note that we indicated our confidence levels in these statements and many

of our scientific findings by using endnotes (e.g., High Confidence) or by using the

IPCC accepted terminology for assessing the likelihood of an outcome having occurred or occurring the in the future. When IPCC authors use the term ‘‘very likely’’

in a sentence, for example, the authors have reached a consensus that an outcome

has an estimated probability of 90 to 99 percent. This terminology was used across

all of the IPCC Working Group II chapters. Also, please note that for every statement made, there is supporting literature cited in the coastal chapter.

Key Policy-Relevant Findings

Since the Third Assessment Report was published in 2001, our understanding of

the implications of climate change for coastal systems and low lying areas (henceforth referred to as ‘coasts’) has increased substantially. In the Executive Summary

of the coastal chapter, we identified six important policy-relevant findings, which

are extracted below from our text:

1. Coasts are experiencing the adverse consequences of hazards related to

climate and sea level rise (very high confidence). They are highly vulnerable

to extreme events, such as storms which impose substantial costs on coastal societies. Annually, about 120 million people are exposed to tropical cyclone hazards

which had killed 250,000 people from 1980 to 2000. Through the 20th century, global rise of sea level contributed to increased coastal inundation, erosion and ecosystem losses, but with considerable local and regional variation due to other factors. Late 20th Century effects of rising temperature include loss of sea ice, thawing

of permafrost and associated coastal retreat, and more frequent coral bleaching and

mortality.

2. Coasts will be exposed to increasing risks over coming decades due to

many compounding climate-change factors (very high confidence). Anticipated climate-related changes include: an accelerated rise in sea level of up to 0.6

m or more by 2100; further rise in sea surface temperatures by up to 3 C; an intensification of tropical and extratropical cyclones; larger extreme waves and storm

surges; altered precipitation/run-off; and ocean acidification. These phenomena will

vary considerably at regional and local scales, but the impacts are virtually certain

to be overwhelmingly negative. Corals are threatened with increased bleaching and

mortality due to rising sea surface temperatures. Coastal wetland ecosystems, such

145

as salt marshes and mangroves, are especially threatened where they are sediment

starved or constrained on their landward margin. Degradation of coastal ecosystems, especially wetlands and coral reefs, has serious implications for the wellbeing of societies dependent on the coastal ecosystems for goods and services. Increased flooding and the degradation of freshwater, fisheries and other resources

could impact hundreds of millions of people and socio-economic costs will escalate

as a result of climate change for coasts.

3. The impact of climate change on coasts is exacerbated by increasing

human-induced pressures (very high confidence). Utilization of the coast increased dramatically during the 20th century and this trend is virtually certain to

continue through the 21st century. Under the Special Report on Emissions Scenarios (SRES), the coastal population could grow from 1.2 billion people (in 1990)

to 1.8 to 5.2 billion people by the 2080s, depending on assumptions about migration.

Increasing numbers of people and assets at risk at the coast are subject to additional stresses by land-use and hydrological changes in catchments, including dams

that reduce sediment supply to the coast. Populated deltas (especially Asian megadeltas), low lying coastal urban areas, and atolls are key societal hotspots of coastal

vulnerability, occurring where the stresses on natural systems coincide with low

human adaptive capacity and high exposure. Regionally, south, southeast and east

Asia, Africa and small islands are most vulnerable. Climate change therefore reinforces the desirability of managing coasts in an integrated manner.

4. Adaptation for the coasts of developing countries will be more challenging than for coasts of developed countries, due to constraints on adaptive capacity (high confidence). While physical exposure can significantly influence the vulnerability for both human populations and natural systems, a lack of

adaptive capacity is often the most important factor that creates a hotspot of human

vulnerability. Adaptive capacity is largely dependent upon development status. Developing nations may have the political or societal will to protect or relocate people

who live in low-lying coastal zones, but without the necessary financial and other

resources/capacities, their vulnerability is much greater than a developed nation in

an identical coastal setting. Vulnerability will also vary between developing countries, while developed countries are not insulated from the adverse consequences of

extreme events.

5. Adaptation costs for vulnerable coasts are much less than the costs of inaction (high confidence). Adaptation costs for climate change are much lower

than damage costs without adaptation for most developed coasts, even considering

only property losses and human deaths. As post event impacts on coastal businesses, people, housing, public and private social institutions, natural resources, and

the environment generally go unrecognized in disaster cost accounting, the full benefits of adaptation are even larger. Without adaptation, the high-end sea level scenarios combined with other climate change (e.g., increased storm intensity) are as

likely as not to render some islands and low-lying areas uninhabitable by 2100, so

effective adaptation is urgently required.

6. The unavoidability of sea level rise even in the longer-term frequently

conflicts with present day human development patterns and trends (high

confidence). Sea level rise has substantial inertia and will continue beyond 2100

for many centuries. Irreversible breakdown of the West Antarctica and/or Greenland

ice sheets, if triggered by rising temperature, would make this long-term rise significantly larger, ultimately questioning the viability of many coastal settlements across

the globe. The issue is reinforced by the increasing human use of the coastal zone.

Settlement patterns also have substantial inertia, and this issue presents a challenge for long-term coastal spatial planning. Stabilization of climate could reduce

the risks of ice sheet breakdown, and reduce but not stop sea level rise due to thermal expansion. Hence, it is now more apparent than in the Third Assessment Report that the most appropriate response to sea level rise for coastal areas is a combination of adaptation to deal with the inevitable rise, and mitigation to limit the

long-term rise to a manageable level.

Human Development Patterns Interact With Climate Drivers and Impacts

on Coastal Systems

Coasts are very likely to be exposed to increasing risks due to climate change and

sea level rise and the effect will be exacerbated by increasing human-induced pressures on coastal areas. One of our main conclusions is that the influence of human

development activities in coasts and adjacent watersheds generally had a more important influence on coastal systems than did climate change during the past century. Utilization of the coast increased dramatically during the 20th Century, a

146

trend that seems certain to continue through the 21st Century. Coastal population

growth in many of the world’s deltas, barrier islands, and estuaries has led to widespread conversion of natural coastal landscapes to agriculture, aquaculture,

silviculture, as well as industrial and residential uses. It has been estimated that

23 percent of the world’s population lives both within 100 km distance of the coast

and less than 100 m above sea level, and population densities in coastal regions are

about three times higher than the global average.

The top bar in the figure below lists the six climate change drivers that are likely

to affect coastal ecosystems, which are generally influenced by a combination of natural processes and human development activity. During the preparation of the

coastal chapter of the IPCC Third Assessment report, sea level rise was the focus

of the available literature relating to climate change and coastal impacts. Sea level

rise still dominates the literature on coastal areas and climate change, but our review shows that more information is now available regarding the effects of increases

in temperature, storm intensity and waves, increased carbon dioxide (CO2) concentration, and changes in run-off.

Increases of extreme sea levels due to changes in storm characteristics are generally of more concern for populated coastal areas than mean sea level rise. The

coastal chapter reports that climate models suggest both tropical and extratropical

storm intensity will increase as the temperature of the atmosphere and sea surface

rise—this implies additional coastal impacts than attributable to sea level rise

alone, especially for tropical and mid-latitude coastal systems. An increase in the

intensity of tropical cyclones entering the Gulf of Mexico, for example, is consistent

with the observed changes in sea surface temperature in the equatorial Atlantic

Ocean where Gulf of Mexico hurricanes form. Changes in other storm characteristics

are less certain and the number of tropical and extra-tropical storms might even reduce. Similarly, extreme wave heights will likely increase with more intense storms.

Changes in run-off driven by changes to the hydrological cycle appear likely, but the

uncertainties are large. Increases in atmospheric CO2 concentrations can enhance

photosynthesis and productivity of plant communities, but because plants respond

differently to the increase in CO2, competition among plant species may alter the

structure of coastal plant communities. Increasing atmospheric CO2 levels can adversely affect coral reefs by decreasing the pH of the ocean, which decreases the carbonate saturation of seawater. The table below summarizes some of the impacts on

coastal systems that are discussed in our chapter.

147

We considered how these climate-related variables would influence the sustainability of each major coastal system and coral reefs. A summary with examples from

our chapter is presented below (note: the specific examples highlighted here comprise only a few of the impacts described in the chapter):

Beaches, rocky shorelines, and cliffed coasts

Most of the world’s sandy shorelines retreated during the past century and sea

level rise is one underlying cause. One half or more of the Mississippi and Texas

shorelines eroded at average rates of 3.1 to 2.6 m/yr since the 1970s, while 90 percent of the Louisiana shoreline eroded at a rate of 12.0 m/yr. In Nigeria shoreline

retreat rates up to 30 m/yr are reported and in the United Kingdom 67 percent of

the coastline experienced a landward retreat of the low-water mark over the past

century. An acceleration in sea level rise will widely exacerbate beach erosion

around the globe, although the local response will depend on the total sediment

budget. Even gravel beaches and soft rock cliffs are vulnerable to climate change

via changes in storm intensity, sea level rise and changes in precipitation patterns,

which affect the physical processes that govern the evolution of these coastal systems. The combined effects of beach erosion and storms can lead to the erosion or

inundation of other coastal systems as well. For example, an increase in wave

heights in coastal bays is a secondary effect of sandy barrier island erosion in Louisiana, and increased wave heights have enhanced erosion rates of bay shorelines,

tidal creeks, and adjacent wetlands.

Deltas

Deltas have long been recognized as highly sensitive to sea level rise. Rates of relative sea level rise can greatly exceed the global average rate of sea level rise in

many heavily populated deltaic areas due to subsidence, including the Chao Phraya

delta, the Mississippi River delta, and the Changjiang River delta because of human

activities. Natural subsidence due to autocompaction of sediment under its own

weight is enhanced by sub-surface fluid withdrawals and drainage, which increases

the potential for inundation, especially for the most populated cities on these deltaic

plains (i.e., Bangkok, New Orleans, and Shanghai). Most of the land area of Bangladesh consists of the deltaic plains of the Ganges, Brahmaputra, and Meghna rivers. Accelerated global sea level rise and higher extreme water levels may have

acute effects on human populations of Bangladesh (and parts of West Bengal, India).

Sea level rise poses a particular threat to deltaic environments, especially when

coupled with the synergistic effects of other climate and human pressures. These effects are best illustrated in large deltas with an area greater than 100,000 km2

(called ‘‘mega-deltas’’ in the IPCC report) due to their often large populations and

important environmental services. The problems of climate change in mega-deltas

are reflected throughout the IPCC Working Group II Fourth Assessment Report

where a number of chapters considered their vulnerability from complementary perspectives. The coastal chapter describes the vulnerability of people living in delta

148

systems across the globe, and concludes that the large populated Asian mega-deltas

are especially vulnerable to climate change. The Mississippi River delta is another

mega-delta that is considered highly vulnerable to the impacts of climate change.

Chapter 10 (Asia Region) examines the Asian mega-deltas in more detail, while

Chapter 5 (Food, Fiber, and Forest Products) examines the threats to fisheries in

the lower Mekong and Mekong delta due to climate change. Hurricane Katrina

made landfall on the Mississippi delta in Louisiana, and the text box below from

the coastal chapter considers different aspects of this important event, which gives

an indication of the likely impacts if tropical storm intensity continues to increase.

Lastly, the Polar Chapter (Chapter 15) considers the specific problems of Arctic

mega-deltas where the advance/retreat of Arctic marine deltas is highly dependent

on the protection afforded by near-shore and land-fast sea ice, which is disappearing

rapidly in the Arctic Ocean. The Mackenzie and Lena river deltas are fed by the

largest Arctic rivers of North America and Eurasia, respectively. In contrast to nonpolar mega-deltas, the physical development and ecosystem health of these deltaic

systems are strongly controlled by cryospheric processes and hence highly susceptible to the effects of climate change.

149

Estuaries and lagoons

Sea level rise will generally lead to higher water levels and salt water intrusion

in coastal estuaries, thereby tending to shift existing coastal plant and animal communities inland. A globally-intensified hydrologic cycle and regional changes in runoff also portend changes in estuarine water quality. Some of the greatest potential

impacts of climate change on estuaries may result from changes in physical mixing

characteristics caused by changes in freshwater runoff. Changes in the timing of

freshwater delivery to estuaries, for example, could lead to a decoupling of the juvenile phases of many estuarine and marine fishery species with available nursery

habitat. Freshwater inflows into estuaries influence water residence time, nutrient

delivery, vertical stratification, salinity, and control of phytoplankton growth rates

in estuaries. Increased water temperature could affect algal production and the

availability of light, oxygen and carbon for other estuarine species. As estuarine

water temperature increases, algal blooms are likely to become more common.

An effect of rising sea level in some hypersaline lagoonal systems, such as the Laguna Madre of Mexico and Texas, will be greater water depths, leading to increased

tidal exchange and hence reduced salinity. As an analogue, the lowering of salinity

in the Laguna Madre since 1949, attributed primarily to the dredging of the Gulf

Intracoastal Waterway and increased drainage from agricultural lands, has shifted

seagrass species from the highly salt tolerant shoalgrass (Halodule wrightii) to manatee grass (Syringodium filiforme), which has a lower salinity tolerance.

A projected increase in the intensity of tropical cyclones and other coastal storms

could alter bottom sediment dynamics, organic matter inputs, phytoplankton and

fisheries populations, salinity and oxygen levels, and biogeochemical processes in estuaries and lagoons.

Mangroves, Salt Marshes and Sea Grasses

Coastal vegetated wetlands are sensitive to climate change because their location

is intimately linked to sea level. Several global and regional analyses suggest significant losses of coastal vegetated wetlands during the 21st Century under scenarios of accelerated sea level rise, with global losses in one study estimated at 33

percent and 44 percent given a 36 cm and 72 cm rise in sea level from 2000 to 2080,

respectively. However, wetland processes are complex and the impacts on any particular tract of marsh or forest will depend upon local rates of sediment accretion,

elevation, vertical land motion (such as subsidence) and other local processes.

Changes in storm intensity can also affect vegetated coastal wetlands (see box on

Hurricane Katrina effects).

Climate change will likely have its most pronounced effects on coastal marshes

through the alteration of hydrologic regimes, specifically, changes in the timing and

volume of water delivered to the coast. Other variables—altered biogeochemistry, altered amounts and pattern of suspended sediments loading, fire, oxidation of organic

sediments and the physical effects of wave energy—may also play important roles

in determining regional and local impacts. Regional losses of coastal marsh are expected to be most severe on the Atlantic and Gulf of Mexico coasts of North and

Central America, the Caribbean, the Mediterranean, the Baltic and most small island regions due to their low tidal range.

Mangrove communities are likely to show a blend of positive (e.g., from higher

levels of CO2 and temperature) and negative (e.g., increased saline intrusion and

erosion) effects, which will largely depend on site specific factors. Increasing salinity

has played a role in the expansion of mangroves into adjacent marshes in the Florida Everglades and throughout southeastern Australia during the past 50 years. Increased salinity of coastal waters since 1950 has contributed to the decline of cabbage palm forests in Florida and baldcypress forests in Louisiana.

Changes in salinity and temperature and increased sea level, atmospheric CO2,

and storm activity will alter seagrass distribution, productivity, and community

composition. Increases in the amount of dissolved CO2 and, for some species, (bicarbonate) HCO3-present in aquatic environments will lead to higher rates of photosynthesis in submerged aquatic vegetation, similar to the effects of CO2 enrichment on

most terrestrial plants, but these changes in aquatic carbon availability can also increase the growth of suspended or epiphytic algae that reduce light needed for sea

grass survival.

Coral Reefs

Coral ‘‘bleaching’’ refers to the loss of symbiotic algae and/or their pigments and

has been observed on many reefs since the early 1980s. Slight paling occurs naturally in response to seasonal increases in sea surface temperature and solar radiation. Corals bleach white in response to anomalously high sea surface temperature

(about 1°C above average seasonal maxima, often combined with high solar radiVerDate 11-MAY-2000 16:07 May 12, 2008 Jkt 032966 PO 00000 Frm 00039 Fmt 6601 Sfmt 6621 C:\WORKD\FULL07\020807\32966A.TXT SCIENCE1 PsN: SCIENCE1
150

ation). If bleaching is prolonged, or if sea surface temperature exceeds 2°C above

seasonal maxima, corals die. The most severe world-wide bleaching events appear

to be associated with El Nin ̃ o events. Major bleaching events were observed in

1982–83, 1987–88, 1994–95, and most extensively in 1998. Since 1998 there have

been several extensive bleaching events. For example, in 2002 bleaching occurred

on much of the Great Barrier Reef and reefs in the eastern Caribbean experienced

a massive bleaching event in late 2005, one of the hottest years on record.

There is very limited evidence that corals can adapt to increases in temperature;

corals and other calcifying organisms (e.g., molluscs, foraminifers) are considered extremely susceptible to increases in sea surface temperature that are likely during

the coming decades. Bleaching events reported in recent years have already impacted many reefs, and their more frequent recurrence is very likely to further reduce both coral cover and diversity on reefs over the next few decades. There are

other threats to reefs associated with climate change apart from coral bleaching, in

addition to non-climatic stresses such as overfishing, pollution and sediment

influxes. Increased concentrations of CO2 in seawater will lead to ocean acidification, which will affect aragonite saturation state and reduce calcification rates of

calcifying organisms such as corals. An increase in tropical storm intensity would

further endanger coral reefs with impacts ranging from minor breakage of fragile

corals to destruction of the majority of corals on a reef.

The bleaching of corals above a certain sea surface temperature is a thresholdtype response that illustrates the complex, nonlinear behavior of coastal systems to

changes in climate. Another temperature-related threshold is the melting of polar

permafrost which results in coastal erosion. Several other types of thresholds characterize the response of coastal systems to climate change and are reported in the

IPCC coastal chapter. The key message is that while some coastal systems do not

appear to be vulnerable to the rates of change experienced during the 20th century,

they each have a limited capacity to adapt to changes in climate and in many cases

there are thresholds at which rapid changes in coastal systems are likely to occur.

Consequences for Human Society

I understand that Dr. Roger Pulwarty from the National Oceanic and Atmospheric Administration is testifying today on Chapter 17 of the IPCC report, titled

Assessment of Adaptation Practices, Options, Constraints and Capacity. Dr.

Pulwarty focuses on adaptation strategies that society can use to adjust to climate

change, to moderate potential damages, to take advantage of opportunities, or to

cope with the consequences.

As Dr. Pulwarty points out, adaptation procedures could increase societal resilience to the negative consequences of climate change in the future. That said, since

much of the world’s population is located at or near the coast and coastal systems

provide many valuable goods and services globally, the changes that we anticipate

in coastal systems will have widespread societal consequences. In our chapter we

presented a synthesis of current knowledge about coastal impacts of climate change

for six different socio-economic sectors, as highlighted below:

1. Freshwater resources—Saltwater intrusion due to sea level rise alone will

have serious economic effects for many coastal communities. Although the

coast contains a substantial proportion of the world’s population, it has a

much smaller proportion of the global renewable water supply, and the coastal population is growing faster than elsewhere, exacerbating this imbalance.

Freshwater supply problems due to climate change are most likely in developing countries with a high proportion of coastal lowland, arid and semi-arid

coasts, coastal megacities (particularly in the Asia-Pacific region), and small

island states.

2. Agriculture, forestry, and fisheries—Climate change is expected to have impacts on agriculture and, to a lesser extent, on forestry. Climate variability

and change also impacts fisheries in coastal and estuarine waters. More frequent extreme climate events, together with higher rainfall intensity and

longer dry spells, may impact negatively on crop yields. Cyclone landfall

causing floods and destruction, have negative impacts on coastal areas, e.g.,

coconuts in India, or sugar cane and bananas in Queensland. Rising sea level

is predicted to have negative impacts on coastal agriculture. Detailed modelling of inundation implies significant changes to the number of rice crops

possible in the Mekong delta under 20–40 cm of relative sea level rise. Rising

sea level potentially threatens inundation and soil salinization of palm oil

and coconuts in Benin and Cote d’Ivoire and mangoes, cashew nuts and coconuts in Kenya.

151

3. Human settlements, infrastructure, and migration—Climate change and sea

level rise affects coastal settlements and infrastructure in several ways. Sea

level rise raises extreme water levels with possible increases in storm intensity portending additional climate impacts on many coastal areas, while saltwater intrusion may threaten water supplies. The degradation of natural

coastal systems due to climate change, such as wetlands, beaches and barrier

islands removes the natural defenses of coastal communities against storm

surge. Hundreds of millions of people are vulnerable to flooding due to sea

level rise, especially in densely populated and low-lying settlements where

adaptive capacity is relatively low and which already face other challenges

such as tropical storms or local coastal subsidence. The numbers affected will

be largest in the mega-deltas of Asia. Africa is also likely to see a substantially increased exposure, with East Africa (Mozambique) having particular

problems due to the combination of tropical storm landfalls and large projected population growth in addition to sea level rise.

4. Human health—Coastal communities, particularly in low income countries,

are vulnerable to a range of health effects due to climate variability and

long-term climate change, particularly extreme weather and climate events

(such as cyclones, floods, and droughts). Communities that rely on marine resources for food are vulnerable to climate-related impacts, in both health and

economic terms. Temperature changes play a role in determining human

health risks, such as from cholera and other enteric pathogens (Vibrio

parahaemolyticus), harmful algal blooms, and shellfish and reef fish poisoning.

5. Biodiversity—The distribution, productivity, and diversity of species in coastal ecosystems is sensitive to variations in weather, climate, and sea level.

Changes in the ranges of invertebrates and waterfowl have already been observed in some coastal regions in response to increases in temperature. It is

clear, however, that responses of intertidal and shallow marine organisms

are more complex than simply latitudinal shifts related to temperature increase, with complex biotic interactions superimposed on the abiotic.

6. Recreation and tourism—Climate change may influence tourism directly via

the decision-making process by influencing tourists to choose different destinations; and indirectly as a result of sea level rise and resulting coastal erosion. In general, air temperature rise is most important to tourism, except

where factors such as sea level rise promotes beach degradation and viable

adaptation options (e.g., nourishment or recycling) are not available. Other

likely impacts of climate change on coastal tourism are due to coral reef degradation. Temperature and rainfall pattern changes may impact water quality in coastal areas and this may lead to more beach closures.

Key Vulnerabilities and Hotspots

A comprehensive assessment of the potential impacts of climate change must consider at least three components of vulnerability: exposure, sensitivity, and adaptive

capacity. The coastal chapter broadly characterizes the sensitivity and natural

adaptive capacity (or resilience) of several major classes of coastal environments to

changes in climate and sea level rise. Differences in geological, oceanographic, and

biological processes can lead to substantially different impacts for a single type of

coastal system (mangroves for example) at different locations. Some global patterns

of vulnerability among systems became evident, however, and are listed below, with

the first three generally at a higher level of risk:

— deltas/estuaries (especially populated mega-deltas)

— coral reefs (especially atolls)

— ice-dominated coasts

— low-lying coastal wetlands

— small islands

— sand and gravel beaches

— soft rock cliffs

Our understanding of human adaptive capacity is less developed than our understanding of responses by natural systems, which limits the degree to which we were

able to quantify societal vulnerability in the world’s coastal regions. Nonetheless,

several key aspects of human vulnerability emerged. It is apparent that multiple

and concomitant non-climate stresses will exacerbate the impacts of climate change

on most natural coastal systems, leading to much larger and detrimental changes

152

in the 21st Century than those of the 20th Century. The table below summarizes

some of the key hotspots of vulnerability that arise from the combination of natural

and societal factors. Note than some examples such as atolls and small islands and

deltas/mega-deltas recur in this table, stressing their high vulnerability.

The coastal chapter contains an assessment of the costs of sea level rise, storm

damage and erosion in the world’s coastal regions. Since the IPCC Third Assessment Report there has been significant progress in moving from classical cost-benefit analysis to assessments that integrate monetary, social, and natural science criteria. Under current climate conditions developing countries bear the main human

burden of climate related extreme events, but it is equally evident that developed

countries are not insulated from disastrous consequences.

Tropical cyclones have major economic, social and environmental consequences for

coastal areas. Up to 119 million people are on average exposed every year to tropical

cyclone hazards. Worldwide, from 1980 to 2000, a total of more than 250,000 deaths

have been associated with tropical cyclones, of which 60 percent occurred in Bangladesh. (This is less than the 300,000 killed in Bangladesh in 1970 by a single cyclone.) The death toll has been reduced in the past decade due largely to improvements in warnings and preparedness, wider public awareness and a stronger sense

of community responsibility. The most exposed countries have densely populated

coastal areas, often located on mega-deltas (China, India, the Philippines, Japan,

Bangladesh).

Between 1980 and 2005, the United States sustained 67 weather-related disasters

each with an overall damage cost of at least U.S. $1 billion. Coastal States in the

southeast United States experienced the greatest number of such disasters. The

total costs including both insured and uninsured losses for the period, adjusted to

2002, were over U.S. $500 billion. There are differing views as to whether climatic

factors have contributed to the increasing frequency of major weather-related disasters along the Atlantic and Gulf coasts of the United States, but the 2007 IPCC

Working Group I report and several independent experts support the view that

storm intensity has increased in some ocean basins (such as the North Atlantic) and

this will continue with global warming. Whichever view is correct, the damage costs

associated with these events are undisputedly high, and will increase into the future, especially if development in coastal areas continues. The following figure from

the coastal chapter shows the differential vulnerability of developed and developing

nations to the effects of sea level rise:

153

Our chapter concludes with a review of adaptation practices, options and constraints for human settlements in coastal zones. The concept of integrated coastal

zone management is discussed with many examples given to illustrate adaptation

practices that will help sustain natural coastal systems, their ecological services and

the human communities that depend upon them. We do note, however, that recent

studies suggest that there are limits to the extent to which natural and human

coastal systems can adapt even to the more immediate changes in climate variability and extreme events. For example, short of mitigation, there is little that humans can do to ameliorate the effects of increased sea surface temperature on coral

reefs—other than reduce the non-climate related pressures of human activity. Without either adaptation or mitigation the impacts of sea level rise and other climate

change such as more intense storms will be substantial, suggesting that some small

islands and low-lying coastal areas may become uninhabitable by 2100.

Two things became immensely clear to us as we concluded this assessment: 1) it

is much more costly to consider the effects of climate change after the fact than to

incorporate climate change into adaptive coastal management now and 2) poor communities (and the poorer parts of communities) and developing coastal and island

nations are particularly vulnerable to the impacts of climate change. Poorer coastal

societies have a limited ability to adapt or cope with change because they tend to

be concentrated in relatively high-risk areas, they have more limited financial and

institutional capacities needed for adaptation, and they are often more dependent

on climate-sensitive resources such as local water and food supplies.

Thank you, Mr. Chairman, for inviting me to summarize our coastal chapter findings. I will be happy to try and answer any questions that you may have.

Chairman GORDON. Thank you, Dr. Burkett, and to complete

your abbreviated introduction, I would like to recognize Mr.

Melancon.

Mr. MELANCON. Thank you, Mr. Chairman. I would like to say

hello to Dr. Burkett. I guess that is a new phenomenon to call her

Burkett. She was Dr. Virginia Vansickel when we worked together

back in the 1970s. I was with the regional planning commission.

154

She was a new, young scientist on the block, so to speak, and has

proved her mettle. Back then it was called coastal zone management. Now it is called coastal erosion restoration. We give it a

whole lot of different names but as you saw by just the one slide

that showed the areas to the east of Louisiana and those that are

my district, which is the fastest disappearing district I believe in

the United States land-mass-wise. She has done quite credible

work. I am proud to call her a friend, a former associate, and I

would like to welcome you here and I am sorry I was running late

to get here. I am trying to visit with people that are still continuing

to flow through my office worried about coastal restoration, hurricane recovery, rebuild and other items that have kept my plate

quite full. But it is good seeing you again, Virginia, and welcome.

Chairman GORDON. Dr. Agrawala is recognized for five minutes.

STATEMENT OF DR. SHARDUL AGRAWALA, PRINCETON UNIVERSITY AND ORGANISATION FOR ECONOMIC CO-OPERATION AND DEVELOPMENT (OECD)

Dr. AGRAWALA. Chairman Gordon and Members of the Committee, thank you for the opportunity to testify this morning. I am

a Visiting Senior Fellow at the Woodrow Wilson School of Public

and International Affairs at Princeton University. I am currently

on sabbatical from the Organisation for Economic Co-operation and

Development in Paris. A short biography can be found at the end

of my testimony.

I served as a Coordinating Lead Author for the chapter on assessment of adaptation practices, options, constraints and capacity

in the Fourth Assessment Report of the IPCC. Dr. Pulwarty, sitting

next to me, was also on this chapter and will be talking next about

some of the implications for the U.S. My testimony will cover some

of the broad findings on adaptation coming out of this chapter.

I would like to offer five take-home messages. The first point I

would like to make is that climate policy is not about making a

choice between adapting to and mitigating climate change. Even

the most stringent mitigation efforts cannot avoid further impacts

of climate change in the next few decades, which makes adaptation

essential. On the other hand, unmitigated climate change would in

the long-term exceed the capacity of natural and human systems

to adapt.

Second, societies have a long record of adapting to the impacts

of weather and climate. In other words, adaptation is not a hypothetical concept. It is taking place now. Crop diversification,

drought monitoring and flood protection are only some of the examples of proactive adaptation measures. Adaptation can also be reactive, for example, an urgency response, disaster recovery and even

migration. Our ability to adapt proactively to current climate variability has increased significantly in recent decades, primarily due

to the development of operational forecasts of El Nin ̃ o and La Nin ̃ a.

NOAA and other agencies have been central to this process.

My third point is that climate change will also require responses

that go beyond adapting to current climates. Climate change often

poses novel risks outside the range of experience, for example,

through accelerated glacier retreat and permafrost melt and

changes in the intensity of heat waves and hurricanes. Even when

155

the impacts of climate change are not yet evident, scenarios of future impacts may already be sufficient to justify some adaptation

measures, particularly for long-lived infrastructure. Just to give

one example, a sewage treatment facility on Deer Island in Boston

Harbor was constructed in 1998 at a much higher elevation, taking

into account anticipate sea-level rise. New York City meanwhile is

considering scenarios of future changes in temperature, rainfall,

sea-level rise and extreme events as part of its review of water supply options. Dr. Rosenzweig on this panel in fact is involved in

these efforts.

My fourth point is that despite our experience and expertise, adaptation is not a slam dunk. There are substantial limits and barriers. Even rich countries have vulnerable populations. Hurricane

Katrina is a prominent example but is not the only one. There were

15,000 excess deaths in less than a month in France in the 2003

heat wave. Further, demographic trends in social choices have in

many cases resulted in maladaptation, and Dr. Burkett mentioned

some of the cases. Even adaptations that have been put in place

to reduce current risks such as levies could engender a false sense

of complacency and exacerbate longer-term vulnerabilities if they

do not incorporate the full range of risk possibilities in their design.

Costs are another barrier. A recent estimate of the World Bank

puts the global incremental annual costs of adaptation to climate

change to be between $10 billion and $40 billion U.S. a year. Information on costs, however, remains very preliminary. We also lack

usable information. Many adaptation decisions are very local at the

level of households, farms, watersheds, infrastructure projects and

cities where reliable climate scenarios are often lacking. Users also

often need information on a whole range of climate-related variables, rainfall, dry spells, winds, snow cover, temperature and rainfall extremes, for their decisions and often such information is either not reliably predicted by climate models or not available. Even

when information exists, access to it is not universal. Further, adaptation is often not a team sport. Actions by one person or a group

can often compound the vulnerability of others.

My fifth and final point is that there is significant room for public policy on adaptation. Adaptation needs to be treated as a core

component of a comprehensive plan of policy. To be effective, consideration of climate risks needs to be integrated within broader

programs ranging from natural resource management to disaster

reduction to international development assistance. Adaptation

should not be pigeonholed as an issue just for climate policy. In

many cases, climate change would require only tweaking of existing policies or better enforcement of existing regulations. Buy-in

from regulatory agencies is therefore critical. In certain cases, climate change would require early actions, in particular, some of the

impacts mentioned by Dr. Rosenzweig. For example, changes in

snow cover, permafrost melt and so on are examples of climate

change impacts occurring now where adaptation measures are

needed. Adaptation to climate change is also needed for infrastructure decisions where decisions today might have a long-term lockin. Government can also play a role in centralizing adaptation by

private actors. In particular market mechanisms are still underutilized for adaptation. Finally, further efforts are also needed in the

156

1 Any opinions, findings, conclusions, or recommendations expressed in this publication are

those of the author and do not necessarily reflect those of Princeton University, the OECD or

its Member governments.

development of provision of usable knowledge for adaptation. This

may require an integrated suite of climate information products

ranging from climate monitoring to seasonal/interannual forecasts

as well as projections for climate change.

Thank you.

[The prepared statement of Dr. Agrawala follows:]

PREPARED STATEMENT OF SHARDUL AGRAWALA1

Assessment of Adaptation Practices, Options, Constraints

and Capacity: The 2007 IPCC Assessment

1. Introduction

Chairman Gordon, Ranking Member Hall, and other Members of the Committee.

Thank you for the opportunity to communicate to you today on some of the recent

findings of the IPCC Working Group II Fourth Assessment Report (AR4).

My name is Shardul Agrawala. I am a Visiting Senior Fellow in Science, Technology and Environmental Policy at the Woodrow Wilson School of Public and International Affairs at Princeton University. I am currently on sabbatical from the

Organisation for Economic Co-operation and Development (OECD) in Paris, where

I have led the work-program on Climate Change and Development for the past five

years. I received my Ph.D. from Princeton University, and have previously worked

on assessments of climate change and variability at Harvard and Columbia Universities. At the OECD, I work closely with our Member governments (which include

the United States) on policies to better integrate consideration of climate risks in

their international development assistance as well as their domestic policies. My

publications include two recent books on adaptation to climate change, and another

on assessing the benefits of climate policies. I was first involved with the Intergovernmental Panel on Climate Change (IPCC) in 1994–95 during the Second Assessment Report when I served as a Lead Author for Working Group II.

For the IPCC Fourth Assessment Report (AR4), I have had the honor to serve as

the Co-ordinating Lead Author (CLA) for Working Group II Chapter 17, Assessment

of Adaptation Practices, Options, Constraints and Capacity, and as a drafting author

for the Technical and Policy-maker Summaries. My testimony today will summarize

some of the main findings from IPCC Working Group II AR4 as they pertain to adaptation—primarily from Chapter 17, but I will first draw upon Chapter 18 to establish the interrelationships between adaptation and mitigation.

2. Adaptation to climate change is necessary, but not sufficient

Both mitigation and adaptation help to reduce the risks of climate change. Mitigation—through the reduction in sources or enhancement of sinks of greenhouse

gases—reduces all impacts of climate change. Adaptation—through adjustments in

human and natural systems to actual or expected climatic changes—can be selective. It can reduce negative impacts, and take advantage of the positive.

The costs of both mitigation and adaptation are predominantly local and nearterm. Meanwhile, the climate related benefits of mitigation are predominantly global and long-term, but not immediate. Owing to lag times in the climate system, the

benefits of current mitigation efforts will hardly be noticeable for several decades.

The benefits of adaptation are more immediate, but primarily local, and over the

short- to medium-term.

Given these differences between mitigation and adaptation, climate policy is not

about making a choice between adapting to and mitigating climate change. Even the

most stringent mitigation efforts cannot avoid further impacts of climate change in

the next few decades, which makes adaptation essential, particularly in addressing

near-term impacts. On the other hand, unmitigated climate change would, in the

long-term exceed the capacity of natural, managed, and human systems to adapt.

3. Adaptation to climate change is occurring now, but on a limited basis

Societies have a long record of adapting to the impacts of weather and climate

through changes in behavior, choices of technology and infrastructure, use of market

instruments, and public policies. Crop diversification, weather and seasonal climate

157

forecasting, drought and hurricane early warning systems, flood protection, weather

derivates, and establishment of coastal-setbacks are only a few examples of

proactive adaptation measures. Adaptation can also be reactive, for example, emergency response, disaster recovery, and even migration.

The IPCC Fourth Assessment Report notes that significant advances have been

made in the ability to adapt to seasonal to inter-annual climate variability. This has

been due to the development of operational capability to forecast El Nin ̃ o and La

Nin ̃ a events and their associated impacts. Institutions to produce seasonal forecasts

have been established and mechanisms are now in place to facilitate the use of this

information for anticipatory adaptation in agriculture, water resource management,

food security, and other sectors. The U.S. Government, through NOAA and other

agencies, has been central to this progress, not only in the domestic context but also

in Latin America, Africa, and Asia.

The Fourth Assessment Report also concludes that climate change is likely to require forward looking investment and planning responses that go beyond responding

to current climate. This is because climate change poses novel risks outside the

range of experience, for example, through accelerated glacier retreat and permafrost

melt, and changes in the intensity of heat waves and hurricanes. Countries ranging

from Nepal to Switzerland are actively reducing risks of hazards associated with the

expansion of glacial lakes and permafrost melt, as a result of rising temperatures.

Even when the impacts of climate change are not yet discernible, scenarios of future

impacts may already be of sufficient concern to justify adaptation responses into

current planning. It may, for example, be cost effective to implement adaptation

measures early on, particularly for long-lived infrastructure. For example, a sewage

treatment facility on Deer Island in Boston harbor was constructed at a higher elevation, taking into account anticipated sea level rise. This was also the case for the

Copenhagen Metro. There are, however, relatively few examples of such infrastructure projects at present.

Comprehensive strategies to adapt to climate change are also being put in place

by a few countries, local governments, and international donors. Countries such as

Finland, France and the UK are establishing national strategies and policy frameworks for adaptation, while donors ranging from the World Bank to the USAID are

undertaking measures to climate-proof their development projects. At the local level,

meanwhile, climate change scenarios are being considered by New York City as part

of a review of its water supply system. Changes in temperature and precipitation,

sea level rise, and extreme events have been examined and an eight step adaptation

assessment procedure has been developed. Among the adaptation measures being

examined are some that could be implemented relatively quickly, such as the tightening of water regulations in the event of an unusually severe drought. Also under

examination are long-term infrastructure adaptations such as the construction of

flood walls around low-lying wastewater treatment plants to protect against sea

level rise and higher storm surges. Such examples, however, are still only ‘‘boutique’’

cases and remain fairly limited relative to the scale of the issue.

4. There are substantial limits and barriers to adaptation

Adaptation is not a slam dunk. For many parts of the developing world adaptation

is constrained by the existence of low coping capacities and inadequate financial and

technical resources to design and implement adaptation measures. However, even

developed countries with high aggregate ‘‘adaptive capacity’’ have vulnerable populations, as was brought home by 15000 excess deaths in France during the 2003

heat wave and the devastation caused by Hurricane Katrina in this country in 2005.

There is also evidence that demographic trends and social choices in both developed and developing countries have, in many cases, resulted in maladaptation. For

example, the conversion of coastal wetlands and the development of settlements and

infrastructure may boost coastal economies but it also increases vulnerability of critical coastal systems to the impacts of current and future climate. Even measures

that have been put in place to reduce current risks—such as levees and dams—

could end up exacerbating longer-term vulnerabilities if they do not incorporate the

full range of risk possibilities.

Adaptation could also entail significant costs. A recent estimate by the World

Bank puts the global incremental annual costs to adapt to climate change to be between U.S. $10 billion to U.S. $40 billion. Information on costs and benefits of adaptation, however, remains very preliminary. Some regional and sectoral studies have

identified adaptation measures that can be implemented at low cost or with high

benefit/cost ratios. The precise estimates of costs and benefits, however, depend

critically on the assumptions made. For example, whether investment in coastal protection is a better strategy than letting a particular coastal region be lost to rising

sea levels depends upon assumptions about how real estate values would adjust as

158

the coastal land gets submerged. Many of the adaptation cost estimates are also

often in a narrow ‘‘engineering’’ sense and do not include the costs of implementation, or the social or economic externalities associated with putting such measures

in place.

Adaptation is also constrained by significant gaps in the knowledge base required

to undertake such actions. For example, climate information is frequently not available at the time and space scales, or for the specific climate variables, that are needed to inform decisions. Mean temperature—which is typically the variable that can

be projected most reliably by climate models—is also often the least relevant for

end-users. Users often need information on the likelihood of extremes for many

operational decisions, which is often less reliable or not available at all. Even when

information exists, individuals and groups may have different risk tolerance, as well

as different preferences about whether and how to respond to such information. And

even when actions are undertaken, the differential power and access to information

and resources may promote adaptive responses by some, while constraining the ability of others to adapt.

5. Some Implications

Based on these findings from the Fourth Assessment Report I will conclude with

a few personal recommendations.

Adaptation needs to be treated as a core component of a comprehensive climate

policy. Consideration of the risks posed by climate change also need to be integrated

within broader programs and budgetary processes, ranging from natural resource

management, to disaster risk reduction, to international aid. In many cases, adaptation to climate change would require better enforcement or further strengthening

of existing regulations. Buy-in from regulatory agencies is therefore critical.

Many adaptation actions will ultimately be undertaken by individuals, communities and private actors. However, the government can play an important role by

promoting the development and provision of usable knowledge that would facilitate

decisions by private actors. This may require an integrated suite of climate information products from climate monitoring, to seasonal/inter-annual as well as climate

change projections. Continuing efforts are also needed to provide information on climate variables, and at the temporal and spatial scales in line with user needs.

Proactive efforts might also be needed to ensure timely and equitable access to such

information.

BIOGRAPHY FOR SHARDUL AGRAWALA

Dr. Shardul Agrawala is a Visiting Senior Fellow in Science, Technology and Environmental Policy at the Woodrow Wilson School of Public and International Affairs at Princeton University. He is currently on sabbatical from the Organisation

for Economic Co-operation and Development (OECD) in Paris, where has led the

work program on Climate Change and Development for the past five years.

Dr. Agrawala received his Ph.D. from Princeton University, and has previously

worked on assessments of climate change and variability at Harvard and Columbia

Universities. His publications include two recent books on adaptation to climate

change, and another on assessing the benefits of climate policies. He was first involved with the Intergovernmental Panel on Climate Change (IPCC) in 1994–95

during the Second Assessment Report when I served as a Lead Author for a chapter

Working Group II.

For the IPCC Fourth Assessment Report (AR4), Dr. Agrawala serves as the Coordinating Lead Author (CLA) for Working Group 11 Chapter 17, Assessment of Adaptation Practices, Options, Constraints and Capacity, and as a drafting author for

the Technical and Policy-maker Summaries.

Chairman GORDON. Thank you.

Dr. Pulwarty, you are recognized for five minutes.

STATEMENT OF DR. ROGER S. PULWARTY, PROGRAM DIRECTOR, NATIONAL INTEGRATED DROUGHT INFORMATION SYSTEM (NIDIS), OFFICE OF OCEANIC AND ATMOSPHERIC RESEARCH, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, U.S. DEPARTMENT OF COMMERCE

Dr. PULWARTY. Good morning, Chairman Gordon, Mr. Ehlers and

the other Members of the Committee. Thank you for this opportunity to speak to you about Working Group II of the IPCC.

159

My name is Roger Pulwarty. I am a physical scientist in the

NOAA Oceanic and Atmospheric Research Climate Program Office

and the program manager for the U.S. National Integrated

Drought Information System, or NIDIS, that was mentioned by Mr.

Hall this morning. I have the honor of serving as the Lead Author

on Chapter 17, as you have heard, also contributing to Chapter 3

on Freshwater Resources and Their Management, a Lead Author on

the forthcoming IPCC Special Report on Climate Change and

Water, and the U.S. Climate Change Science Program Report on

Weather and Climate Extremes in a Changing Climate.

The focus of my testimony is on the results of Chapter 17, especially as they relate to the United States and to water resources.

Chapter 17 sought to address the following questions in the context

of climate: what are our adaptation strategies, as you have heard,

and how can they be implemented; what are the benefits, costs and

limits of such adaptation strategies, and more importantly, what

are in fact good adaptation practices.

The IPCC definition of climate change refers to any change in climate over time, whether due to natural variability or as a result

of human activity. It is thus the goal of good adaptation strategies

to take advantage of opportunities and to reduce the risks associated with variability and change. It is important to note that climate change could in the long-term exceed the capacity of particular natural and managed systems to adapt.

Climate change adaptation strategies will be important for various sectors of the U.S. economy and society and may be implemented in a number of ways. Some adaptation strategies and initiatives are infrastructure-based and may require major up-front

investments. One example that you have heard about is the Deer

Island sewage facility in Boston Harbor which, it should be noted,

was completed in 1998. A more complex but potentially major mode

of adaptation to climate change will involve shifts in land use, watershed, ecosystems and livelihoods. Adaptation strategies and

practices in the United States have been observed in the insurance

sector and are focused on property damage. As a result of climate

change, demand for insurance products is expected to increase. At

the same time, however, climate change effects could reduce insurability and threaten insurance schemes, possibly resulting in the

States becoming the insurer of last resort. As we have seen in the

aftermath of recent hurricane seasons such as 2004 and 2005, it

can take only one major climatic event to set such changes into motion. Adaptation strategies and implementation initiatives in infrastructure, insurance, financial markets and collaborative resource

management may be needed to address water availability and

quality.

One critical area is the western United States. Projected warming in the western mountains of North America is very likely to

cause decreased snowpack, more winter flooding due to earlier runoff, and reduced summer flows. These effects will exacerbate competition for already overallocated water resources. For example, in

the case of Sacramento-Joaquin River and the Colorado River

basin, stream flow changes projected beyond 2020 indicate that it

may not be possible to fulfill water demands in those basins. If climate change results in greater water scarcity relative to demands,

160

future adaptations will be necessary to address competition for

water and may include improved water use efficiency and better

demand management through metering, pricing and other mechanisms. We might also have to address institutional changes that

improve the tradability of water rights while securing water for the

environmental services that we depend upon. Voluntary water

transfers including short-term water leasing, the permanent sale of

water rights from agricultural to urban and environmental uses

are becoming increasingly common in our western States. In California, adaptive management measures include water conservation,

reclamation and the combined use of surface and groundwater and

the desalination of brackish water. These have all been advocated

as means of proactively responding to water scarcity. It takes time

to fully implement such changes so adaptations such as these are

likely to become more effective as we learn and time passes.

A major barrier to implementing adaptive measures in the

United States is that adaptation is not currently a high priority.

Many adaptation strategies can be implemented at low cost. The

comprehensive estimates of adaptation costs, benefits and the limitations of the practices themselves are currently lacking. Coping

with uncertainties associated with estimates of future climate

change and the effects on economic and environmental resources

means that we will have to adopt management strategies and

measures that are robust enough to apply across a range of potential scenarios about the future. Adaptive capacity to manage climate changes can be increased by introducing adaptation measures

into existing watershed, water sources, urban and coastal management plans and operations. One option based on experience is to

develop research and management partnerships that provide decision-makers with credible, relevant and timely climate information

and to improve the capacity to use such information for risk management. The IPCC report refers to such activities as

mainstreaming. By doing so, adaptation to climate change will become part of other well-established programs to increase societal

resilience and to increase national benefit.

I am happy to answer questions that the Members might have.

Thank you.

[The prepared statement of Dr. Pulwarty follows:]

PREPARED STATEMENT OF ROGER S. PULWARTY

Chairman Gordon, Ranking Member Hall, and other Members of the Committee,

thank you for the opportunity to speak with you today on the Working Group II report of the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment

Report—‘Climate Change 2007.’

My name is Roger Pulwarty. I am a Physical Scientist in the NOAA Office of Oceanic and Atmospheric Research Climate Program Office and the program manager

for the U.S. National Integrated Drought Information System. As a contributor to

the Intergovernmental Panel on Climate Change Working Group II, I have had the

honor of serving as a lead author on Chapter 17, Assessment of Adaptation Practices, Options, Constraints and Capacity, and as a contributor to the Chapter 3,

Freshwater Resources and Their Management. I am also a lead author on the forthcoming IPCC Special Report on Climate Change and Water, and on the author team

for the U.S. Climate Change Science Program, Synthesis and Assessment Report on

Weather and Climate Extremes in a Changing Climate. My role in the latter two

reports focused on impact assessment and adaptation responses.

Working Group II was charged with assessing the scientific, technical, environmental, economic, and social aspects of vulnerability (sensitivity and adaptability)

to climate change, and, the negative and positive consequences for ecological sysVerDate 11-MAY-2000 16:07 May 12, 2008 Jkt 032966 PO 00000 Frm 00050 Fmt 6601 Sfmt 6621 C:\WORKD\FULL07\020807\32966A.TXT SCIENCE1 PsN: SCIENCE1
161

tems, socio-economic sectors, and human health. As you know, the report of Working

Group I (released on February 2, 2007) covered physical climate science, while the

Working Group III report will cover greenhouse gas mitigation. Chapter 17 of the

Working Group II report focused on the following issues for different sectors (e.g.,

water, agriculture, biodiversity) and communities (coastal, island, etc.):

• The role of adaptation in reducing vulnerability and impacts,

• Assessment of adaptation capacity, options and constraints, and

• Enhancing adaptation practice and operations.

Given the expertise of my colleagues on this panel, I will focus my testimony on

the results of Chapter 17, especially as they relate to water resources.

Chapter 17 sought to address the following questions in the context of climate

variability and change:

• What are we adapting to?

• What are adaptation strategies?

• How can they be implemented?

• What are the benefits, costs and limits of such strategies?

• What are good adaptation practices?

The IPCC definition of climate change refers to any change in climate over time,

whether due to natural variability or as a result of human activity. Climate and

non-climatic factors can interact to produce opportunities or disaster. It is the goal

of good adaptation practices to take advantage of such opportunities and to reduce

associated risks. Climate variability and change influence events across timescales

from a few hours or a season (e.g., floods and droughts) to year-to-year variability

(e.g., El Nin ̃ o-Southern Oscillation events). When changes in these types of events

persist, decadal and longer-term trends also change. Adaptation strategies must

therefore be engaged across all of these timescales.

Adaptive capacity is the ability of a system to adjust to climate change (including

climate variability and extremes) to moderate potential damages, take advantage of

opportunities, or cope with the consequences. Vulnerability is a function of the character, magnitude, and rate of climate change and variation to which a system is exposed, as well as the sensitivity and adaptive capacity of the system. Non-climactic

factors are increasingly the most important influences on risk and thus, given a particular setting, even small climate changes can produce disproportionate impacts. It

is not an either/or question as to whether the magnitude of societal impacts are a

function of climate variability and change or of societal conditions alone. It is always

a combination of both factors.

Adaptation to climate change occurs in the context of multiple stresses. Due to

the inertia of the climate system, if emissions are reduced now, their effect in avoiding impacts by slowing the rate of temperature increase will not emerge until after

several decades. Vulnerable populations, especially in the developing world and in

poorer and elderly communities, have limited capacity to deal with climate shocks.

Adaptation, therefore, will be important in coping with current climate

vulnerabilities and early impacts in the near-term, and will help build resilient

economies as our climate changes, regardless of how that change is derived. It is

important to note that unmitigated climate change could, in the long-term, exceed

the capacity of different natural, managed and human systems to adapt.

Examples of adaptation initiatives

Early examples where climate change scenarios have already been incorporated

into infrastructure design to accommodate projected sea-level rise include the Confederation Bridge in Canada and the Deer Island sewage treatment plant in Boston

harbor in the United States. The Confederation Bridge is a 13 kilometer bridge between Prince Edward Island and the Canadian mainland. The bridge provides a

navigation channel for ocean-going vessels with vertical clearance of about 50 meters. Sea level rise was recognized as a principal concern during the design process

and the bridge was built one meter higher than currently required to accommodate

sea level rise from thermal expansion over its hundred year lifespan. In the case

of the Deer Island sewage facility, the design called for raw sewage collected from

communities onshore to be pumped under Boston harbor and then up to the treatment plant on Deer Island. After waste treatment, the effluent would be discharged

into the harbor through a downhill pipe. Design engineers were concerned that sea

level rise would necessitate the construction of a protective wall around the plant,

which would then require installation of expensive pumping equipment to transport

the effluent over the wall. To avoid such a future cost the designers decided to keep

the treatment plant at a higher elevation, and the facility was completed in 1998.

162

There are several other examples of designers and engineers factoring particular aspects of climate change into their plans as projects have been undertaken around

the world. These examples are primarily infrastructure-based adaptations requiring

major upfront investments. A more complex, but potentially dominant mode of adaptation will be the potential for shifts in land use, ecosystems and livelihoods necessary to accommodate a new climatic regime.

To date, most adaptation practices have been observed in the insurance sector and

have focused on property damage. Financial markets can internalize information on

climate risks and help transfer adaptation and risk reduction incentives to communities and individuals while capital markets and transfer mechanisms can alleviate

financial constraints to the implementation of adaptation measures. As a result of

climate change, demand for insurance products is expected to increase, while at the

same time climate change impacts could reduce insurability and threaten insurance

schemes, possibly resulting in States being the insurer of last resort. While these

market signals can play a role in transferring adaptation incentives to individuals,

reduced insurance coverage can, at the same time, impose significant economic and

social costs. Market signals have also fostered risk prevention through: (i) implementing and strengthening building standards; (ii) planning risk prevention measures and developing best practices, and (iii) raising awareness of policyholders and

public authorities. In the longer-term, climate change may also induce insurers to

adopt forward-looking pricing methods in order to maintain insurability.

Water availability and water demand in North America: What are the adaptation options?

Projected warming in the western mountains of North America is very likely to

cause decreased snowpack, more winter flooding due to earlier runoff, and reduced

summer flows, exacerbating competition for over-allocated water resources. In the

case of the Sacramento-Joaquin River and the Colorado River basins in the Western

United States, for example, streamflow changes projected beyond 2020 indicate that

it may not be possible to fulfill all of the present-day water demands (including environmental targets), even with adapted reservoir management. By 2050 the Sacramento and Colorado River deltas could experience dramatic increases in salinity

and subsequent ecosystem disruption.

If climate change results in greater water scarcity relative to demands, future adaptations may include technical changes that improve water use efficiency, demand

management (e.g., through metering and pricing), and institutional changes that improve the tradability of water rights. If climate change affects water quality, adaptive strategies will have to be developed to protect the ensuing human uses, ecosystems and aquatic life uses. It takes time to fully implement such changes, so

they are likely to become more effective as time passes. The availability of water

for each type of use may be affected by other competing uses of the resource. Consequently a complete analysis of the effects of climate change on human water uses

should consider cross-sector interactions, including the impacts of changes in water

use efficiency and intentional transfers of the use of water from one sector to another. For example, voluntary water transfers (including short-term water leasing

and permanent sales of water rights) from agricultural to urban or environmental

uses are becoming increasingly common in the Western United States.

Increases in consumptive water use can reduce downstream areas of water supply

that would have re-entered the stream as return flow. Such upstream uses could

make irrigation infeasible in the lower reaches of basins that experience reduced

streamflow. Thus the costs and consequences of adaptive mechanisms are as important as the adaptations themselves. It is important to ensure that emergency adjustments to events such as hurricanes, heat waves, and droughts do not increase vulnerability to longer-term changes. Thus increasing adaptive capacity in the nearterm to manage climate changes as they occur becomes important.

Ensuring that present adaptation strategies also decrease long-term vulnerability by enhancing adaptation practice and operations under

uncertainty:

Climate change poses a major conceptual challenge to resource managers, in addition to the challenges caused by population and land use change. For example it

is no longer appropriate to assume that past hydrological conditions will continue

into the future (the traditional assumption). Due to the uncertainty associated with

climate change, managers cannot place confidence in single projections of the future.

It will be difficult to detect a clear climate change effect within the next couple of

decades, even with an underlying trend. The vast majority of published impact assessments have used only a small number of scenarios of the future. These have

demonstrated that impacts vary among scenarios, although temperature-based imVerDate 11-MAY-2000 16:07 May 12, 2008 Jkt 032966 PO 00000 Frm 00052 Fmt 6601 Sfmt 6621 C:\WORKD\FULL07\020807\32966A.TXT SCIENCE1 PsN: SCIENCE1
163

pacts, such as changing in the timing of streamflows, tend to be more robust. The

use of a scenarios-based approach to water management in the face of climate

change is recommended, but poses two problems. First, the large range for different

climate model-based temperature scenarios suggests that adaptive planning should

not be based on only a few scenarios; there is no guarantee that the range simulated

by the models represents the full range of temperatures that could be experienced.

Second, it is difficult to evaluate the credibility of individual scenarios, and uncertainty injects additional complications. Based on the studies done so far, it is difficult to reliably predict the water-related consequences of climate policies and emission pathways. Adaptation procedures that do not rely on precise projections of

changes in river discharge, groundwater, and other variables need to be developed.

Consequently, research on methods of adaptation in the face of these uncertainties

is needed. Whereas it is difficult to make concrete projections, it is known that

hydrological characteristics will change in the future. Early warnings of changes in

the physical system and of thresholds or critical points that affect management priorities become important. Water managers in some countries are already considering explicitly how to incorporate the potential effects of climate change into specific designs and multi-stakeholder settings. Integrated water resources and coastal

zone management, are based around the concepts of flexibility and adaptability,

using measures which can be easily altered or are robust to changing conditions.

For example, in California adaptive management measures (including water conservation, reclamation, conjunctive use of surface and groundwater and desalination

of brackish water) have been advocated as means of proactively responding to climate change threats on water supply. Similarly, resilient strategies for flood management and environmental restoration, such as allowing rivers to temporarily flood

and reducing exposure to flood damage, might be preferable to or combined with traditional ‘‘resistance’’ (protection) strategies, such as in the Confederation Bridge case

discussed above.

Adaptation procedures and decision support tools are important both in the context of present day climatic risks and for increasing societal resilience into the future. To develop the necessary procedures and tools requires continued scientific,

technical and operational efforts. The focus of such efforts is on developing research

and management partnerships that provide decision-makers and communities with

credible, relevant information and the capacity to use such information effectively

for climate risk management. Experience has shown that such knowledge and capacity is most effectively produced through:

• Enhancement of networks of systematic observations of key elements of physical, biological, managed and human systems affected by climate change particularly in regions where such networks have been identified as insufficient;

• Research into understanding and managing physical, biological and human

systems where there is a risk of irreversible change due to climate and other

stresses;

• Increased understanding of the potential costs and benefits of impacts due to

various amounts of climate change, of damages avoided by different levels of

emissions reduction, and of options for adapting to these impacts and managing the risks;

• Studies to explore how adapting to climate change and the pursuit of sustainable development can be complementary; and

• Learning-by-doing approaches, where the base of knowledge is enhanced

through accumulation of practical experience.

Summary

Climate is one factor among many that produce changes in our environment. Demographic, socio-economic and technological changes may play a more important

role in most time horizons and regions. In the 2050s, differences in the population

projections of the four scenarios contained in the IPCC Special Report on Emission

Scenarios show that population size could have a greater impact on people living

in water-stressed river basins (defined as basins with per-capita water resources of

less than 1000 m3/year) than differences in emissions scenarios. As the number of

people and attendant demands in already stressed river basins increase, even small

changes in natural or anthropogenic climate can trigger large impacts on water resources.

Adaptation is unavoidable because climate is always varying even if changes in

variability are amplified or dampened by anthropogenic warming. In the near-term,

adaptation will be necessary to meet the challenge of impacts to which we are already committed. There are significant barriers to implementing adaptation in comVerDate 11-MAY-2000 16:07 May 12, 2008 Jkt 032966 PO 00000 Frm 00053 Fmt 6601 Sfmt 6621 C:\WORKD\FULL07\020807\32966A.TXT SCIENCE1 PsN: SCIENCE1
164

plex settings. These barriers include both the inability of natural systems to adapt

at the rate and magnitude of climate change, as well as technological, financial, cognitive and behavioral, social and cultural constraints. There are also significant

knowledge gaps for adaptation, as well as impediments to flows of knowledge and

information relevant for decision-makers. In addition, the scale at which reliable information is produced (i.e., global) does not always match with what is needed for

adaptation decisions (i.e., watershed and local). New planning processes are attempting to overcome these barriers at local, regional and national levels in both

developing and developed countries.

The assessment in Chapter 17 leads to the following conclusions:

• Adaptation to climate change is already taking place, but on a limited

basis.1

• Adaptation measures are seldom undertaken in response to climate

change alone.1

• Many adaptations can be implemented at low cost, but comprehensive estimates of adaptation costs and benefits are currently lacking.2

• Adaptive capacity is uneven across and within societies.1

1= Very high confidence.

2= High confidence.

In the IPCC Summary for Policy-makers, the following terms have been used to

express confidence in a statement: Very high confidence = At least a 9 out of 10

chance of being correct, High confidence = About an 8 out of 10 chance, Medium

confidence = About a 5 out of 10 chance, Low confidence = About a 2 out of 10

chance, Very low confidence = Less than a 1 out of 10 chance.

Adaptive capacity to manage climate changes can be increased by introducing adaptation measures into development planning and operations (sometimes termed

‘mainstreaming’). This can be achieved by including adaptation measures in landuse planning and infrastructure design, or by including measures to reduce vulnerability in existing disaster preparedness programs (such as introducing drought

warning systems based on actual management needs).

The major barriers to implementing adaptive management measures are that adaptation to climate change is not as yet a high priority, and the validity of local

manifestations of global climate change remains in question. Coping with the uncertainties associated with estimates of future climate change and the impacts on economic and environmental resources means we will have to adopt management measures that are robust enough to apply to a range of potential scenarios, some as yet

undefined. Empirical research carried out since the IPCC Third Assessment Report

(2001) has shown that there are rarely simple cause-effect relationships between climate change risks and the capacity to adapt. Adaptive capacity can vary over time

and is affected by multiple processes of environmental and societal change as societies adjust from event (drought, flood, abrupt change) to event. Greenhouse gas

mitigation is not enough to reduce climatic risks, nor does identifying the need for

adaptations translate into actions that reduce vulnerability. By implementing

mainstreaming initiatives, adaptation to climate change will become part of, or will

be consistent with, other well-established programs to increase societal resilience,

particularly environmental impacts assessments, adaptive management and sustainable development.

BIOGRAPHY FOR ROGER S. PULWARTY

Roger S. Pulwarty is a Physical Scientist at the U.S. Department of Commerce/

NOAA/Office of Oceanic and Atmospheric Research Climate Program Office. He

joined NOAA from the University of Colorado faculty in July 2006. Roger is the Program Director of the interagency and interstate National Integrated Drought Information System (NIDIS). He also leads the risk assessment component of the World

Bank/NOAA project on ‘‘Mainstreaming Adaptation to Climate in the Caribbean.’’

Roger holds a Ph.D. (1994) in Climatology from the University of Colorado, Boulder.

From 1998–2002 Roger managed the NOAA/Regional Integrated Sciences and Assessments (RISA) Program.

Roger’s research and applied interests have focused on, (1) social and environmental vulnerability to climate variability and change in the Americas; and (2) designing climate-related services to meet information needs in water resources, ecosystem and agricultural management in the United States. In addition to the National Research Council, Roger has served in advisory capacities to various federal

165

and State agencies, the Glen/Grand Canyon Adaptive Management Program, and to

the UNDP, UNEP, World Bank and the Organization of American States. He is a

lead-author on the IPCC Fourth Assessment Report Working Group 2, the forthcoming IPCC Special Report on Climate Change and Water, and on the U.S. Climate

Change Science Program Synthesis report on climate and weather extremes. Roger

is Professor Adjunct at the University of Colorado, Boulder and the University of

the West Indies. He is the co-editor of Hurricanes: Climate and Societal Impacts

(Springer, 1997).

Chairman GORDON. Thank you, Doctor.

Dr. Schneider, you are recognized.

STATEMENT OF DR. STEPHEN H. SCHNEIDER, MELVIN AND

JOAN LANE PROFESSOR FOR INTERDISCIPLINARY ENVIRONMENTAL STUDIES; PROFESSOR, DEPARTMENT OF BIOLOGICAL SCIENCES; SENIOR FELLOW, CENTER FOR ENVIRONMENTAL SCIENCE AND POLICY AT THE WOODS INSTITUTE FOR THE ENVIRONMENT, STANFORD UNIVERSITY

Dr. SCHNEIDER. Thank you very much, Congressman Gordon,

distinguished Members. If you would indulge me in a short personal preference, for me, sitting here under the watchful eye of

George Brown, reminding myself that 31 years ago as a 31-yearold I first testified to this committee, and at the time the issue was

creating a national climate program office to deal with the fact that

even then we were well aware that the use of the atmosphere as

the recipient for tailpipe and smokestack emissions could well

cause problems from the climate point of view. We were just becoming aware at the time that warming was emerging from cooling

as the most likely event and clearly it was mostly theoretical projections forward for which we wanted to create the office.

If I had to summarize, as I am often forced to do in a media

interview, so what is new in the last 31 years, I would argue that

I guess it is that nature has been cooperating with theory and the

projections of discernible change by the end of the century, increased heat waves, reduced cool waves and the further stress on

things such as intensity of hurricanes would occur and did, ice

would be shrinking, as we heard from Cynthia Rosenzweig and so

forth. There has been a great breakthrough in our theoretical understanding since 31 years ago. It is that some of those concerns

have become so manifest in the observational record that there is

now a much larger constituency for paying serious attention to the

problem, and I appreciate your interests in that.

So with that having been said, I have been the coordinating lead

author with others of a summary chapter, Chapter 19 in the Working Group II report, which is the key vulnerabilities and the risks

from climate change. Now, IPCC tends to be a rather arcane venture to many people with snippets in the press and I thought I

would spend a minute of my time just giving you a little background on how we get to choose what we write about and what literature we assess. First I would say that we aren’t simply librarians. It is not our job just to say what it is in the literature and

there is so much, you can’t put it all in anyway in an 800-page report. Our job is to assess what is relevant to the questions given

to us by governments which are policy-relevant to them and to be

sure that we provide clear statements of the credibility of the

166

science so that confidence judgments can be made whether it is

likely or speculative and so forth.

I guess the last thing you want after a long panel is lots of

words, so I have highlighted in red the key words given our title

of key vulnerability of our Plenary Agreed Outline. This is a negotiated document by the over 100 governments that meet and that

give us a direction which all chapters are required to do, and I give

you the example from my chapter. If you wanted to see it in detail,

it is in my written submission. But just to highlight a few issues.

In the front bullet, issues related to Article 2 of the U.N. Framework Convention on Climate Change. That is the one which said

that nations are committed to prevent—to stabilize greenhouse gas

concentrations in the atmosphere so as to prevent ‘‘dangerous anthropogenic interference with the climate system.’’ We also were

asked to identify key impacts and vulnerabilities, key risks for regions, stabilization strategies. We were asked in the context of impacts and vulnerabilities how could those vulnerabilities be reduced

under at least the umbrella of stabilization and then finally, the

last bullet is uncertainties and it is inconceivable when anybody is

dealing with a system as complex not just as the climate system

but the coupling, the interaction of climate systems and human

systems that there wouldn’t be substantial uncertainties, which is

why we have confidence ratings.

One more point about uncertainties. Having been the coauthor of

the Guidance Paper on Uncertainties for the previous assessment

report, what we ask assessors to do and what has been done since

is not just to state that there is uncertainty but to rank the components of the issues which are well established, and there are many,

from the components of the issues with competing explanations

from the components that are speculative. All too often they get

lumped up in the media debate and create a cacophonous picture

where people are confused. So the job of these assessment reports

whether IPCC or the National Research Council, is to try to separate those out.

The next picture—well, I will just talk to it then—is that—well,

okay. If the slide were showing—okay. What it would be showing

is that in the process of identifying that, we can come up with a

number of items that are ‘‘key vulnerabilities.’’ The context was

avoiding dangerous climate change and many governments said

‘‘Well, could you in Chapter 19 give us some guidance on avoiding

dangerous climate?’’ and we said ‘‘No, of course we can’t because

the choice of dangerous is a value judgment about how you weigh

risks of potential climate changes versus the risks of spending

money that you want to use for other purposes. That is your job;’’

but what we can do is, we can give procedures whereby we can

make it clearer what the tradeoffs are and what the criteria are for

which people in the literature have identified things as key, and we

came up with a list of seven criteria, and I will end with these: the

magnitude of impacts, timing of impacts, persistence and reversibility of impacts, potential for adaptation, distributional aspects,

meaning do rich get richer and poor get poorer or the other way

around, likelihood, uncertainty is very important, and the importance of those systems, and no statement could be more of a value

judgment than importance, and we explicitly stated that it is not

167

the role of science to define or explain which vulnerabilities are key

but it is our role to try to help to give criteria whereby stakeholders and decision-makers can be more ordered in their capacity

to make their own judgments, and that is why the chapter lays

that out. This was explicitly stated in the chapter. It is explicitly

stated in the testimony though a little bit of it was removed from

the summary for policy-makers but the important gist is still there.

Thank you very much.

168

169

170

[The prepared statement of Dr. Schneider follows:]

PREPARED STATEMENT OF STEPHEN H. SCHNEIDER

I. Background of IPCC Assessment Process.

Assessment of the description, causes and implications of climate change is made

on the basis of scientific analyses of a very complex coupled human-natural system

requiring knowledge from physical, biological and social sciences, as well as the

technology and the development communities. This implies that there will be a

great deal of uncertainty in many elements of any such an assessment. Effective assessments try to separate out from the scientific literature and various often-contradictory claims from stakeholder groups the elements of scientific analysis that

are well established, from those that are best characterized by competing explanations, from those that are more speculative. Given the complexities, it is often

very difficult for non-specialists to sort out this ordered set of conclusions from established to speculative and thus governments have turned to assessment bodies to

help with that process. In the U.S., for example, the National Research Council

(NRC) has produced dozens of reports on climate change science and policy options

that have important influence owing to their credibility, as each is heavily peer reviewed and produced by scientists known to be field leaders. However, national reports are less credible sometimes in other countries, and thus in the late 1980s governments set up an international assessment institution parallel to the NRC that

would have a broad representation of disciplines, groups and nations.

The credibility of these Intergovernmental Panel on Climate Change (IPCC) assessments has generally been very high for similar reasons to the NRC reports:

front rank scientists and others are joined together as Lead Authors, three rounds

of reviews are undertaken, Lead Authors must justify their response to reviewers

satisfactorily to a panel of about three Review Editors for each chapter, and governments approve line by line the Summary for Policy-makers (SPM) in a week-long

Plenary at the end of the writing process—typically about three years. There are

three working groups: Working Group 1 on the science of climate change and projections of its trends, Working Group 2 on the impacts of climate changes on environment and society and Working Group 3 on the policy implications. There is some

overlap among topics mandated for each working group to address, and thus there

are some Lead Authors in common in more than one report, as well as a Synthesis

Report produced by lead authors from all working groups after the three more disciplinary working group reports are approved. The assessors are charged with addressing policy-relevant questions—such as the pros and cons of policy alternatives

as expressed in the literature—as dictated in a government document (the PlenaryVerDate 11-MAY-2000 16:07 May 12, 2008 Jkt 032966 PO 00000 Frm 00060 Fmt 6601 Sfmt 6621 C:\WORKD\FULL07\020807\32966A.TXT SCIENCE1 PsN: SCIENCE1
171

Agreed Outline—PAO); but authors are asked to avoid being policy prescriptive—

that is, expressing preferences on implementing any of the many options analyzed.

In this testimony I will focus on the chapter I was a Coordinating Lead Author for:

IPCC Working Group II Fourth Assessment Report.

‘‘Chapter 19, Assessing Key Vulnerabilities and the Risk from Climate Change.’’

II. Scope of Chapter 19.

The Plenary Agreed Outline (PAO) for Chapter 19 is as follows:

‘‘19. Assessing Key Vulnerabilities and the Risk from Climate Change

• Methods and concepts: issues relating to Article 2 of the UNFCCC; reasons

for concern; measuring damage; identifying key impacts and vulnerabilities,

and their risk of occurrence

• Approaches to determining levels of climate change for key impacts

• Assessing key global risks

• Assessing key risks for regions and sectors

• Assessment of response strategies to avoid occurrence: stabilization scenarios;

mitigation/adaptation strategies; avoiding irreversibilities; role of sustainable

development; treatment of uncertainty

• Uncertainties, unknowns, priorities for research.’’

Therefore, our chapter addresses each of these topics by reviewing the literature

and evaluating the state of the science. It is not simply a listing of the works in

the literature that constitutes an assessment, but an evaluation of the confidence

that the authors have in the quality of the science and its relevance for decisionmakers. The latter is determined by both the PAO (at the outset) and by (in the

middle of the writing process) reviews from experts and governments, as these reviews help Lead Authors to sort out what materials to include from the vast array

of possibilities in the literature and to establish a consensus on the confidence in

the state of the science or key conclusion. Since the title of Chapter 19 includes the

word ‘‘Key,’’ I will first explain how that PAO-required issue was addressed by the

authors, drawing primarily from the text of the chapter. In the following, the square

brackets with numbers in them are the sections of the semi-final draft of Chapter

19 where the detailed information on the topic can be obtained. After final consistency checking, the final chapter will be available on the IPCC Working Group II

website about early May 2007.

III. Defining and Assessing What Is a ‘‘Key Vulnerability.’’

Climate change will lead to changes in geophysical, biological and socio-economic

systems. An impact describes a specific change in a system caused by its exposure

to climate change. Impacts may be judged to be harmful or beneficial. Vulnerability

to climate change is the degree to which these systems are susceptible to, and unable to cope with, the adverse impacts. The concept of risk, which combines the

magnitude of the impact with the probability of its occurrence, captures uncertainty

in the underlying processes of climate change, exposure, impacts and adaptation.

[19.1.1]

Many of these impacts, vulnerabilities and risks merit particular attention by policy-makers due to characteristics that might make them key. The identification of

potential key vulnerabilities is intended to provide guidance to decision-makers for

identifying levels and rates of climate change that may be associated with ‘‘dangerous anthropogenic interference’’ (DAI) with the climate system, in the terminology of United Nations Framework Convention on Climate Change (UNFCCC) Article 2. The precise language of Article 2—which the United States has signed and

ratified—relevant to Chapter 19 is:

‘‘The ultimate objective of this Convention and any related legal instruments

that the Conference of the Parties may adopt is to achieve, in accordance with

the relevant provisions of the Convention, stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system. Such a level should be achieved

within a time-frame sufficient to allow ecosystems to adapt naturally to climate

change, to ensure that food production is not threatened and to enable economic

development to proceed in a sustainable manner.’’

Ultimately, the definition of DAI cannot be based on scientific arguments alone,

but involves other judgments informed by the state of scientific knowledge. No single metric can adequately describe the diversity of key vulnerabilities, nor determine their ranking. [19.1.1]

172

This chapter identifies seven criteria from the literature that may be used to identify key vulnerabilities, and then describes some potential key vulnerabilities identified using these criteria. The criteria are [19.2]:

— magnitude of impacts

— timing of impacts

— persistence and reversibility of impacts

— potential for adaptation

— distributional aspects of impacts and vulnerabilities

— likelihood (estimates of uncertainty) of impacts and vulnerabilities and confidence in those estimates

— importance of the system(s) at risk

Key vulnerabilities are associated with many climate-sensitive systems, including

food supply, infrastructure, health, water resources, coastal systems, ecosystems,

global biogeochemical cycles, ice sheets, and modes of oceanic and atmospheric circulation. [19.3]

In order to provide guidance to decision-makers on the kinds of impacts that

many in the literature could consider ‘‘key,’’ Chapter 19 prepared a synthetic summary table of representative key impacts, risks and vulnerabilities, as was required

from our Plenary Agreed Outline. After many rounds of review and exchanges with

authors in other chapters in all working groups, the following table has emerged.

Confidence levels from the literature, other chapters, reviewers, and the Chapter 19

authors’ scientific judgments are amalgamated and appear in the table with ‘‘o’’ implying low confidence (about 2 in 10 chance), ‘‘*’’ medium confidence (about a 5 in

10 chance of occurring), ‘‘**’’ high confidence (about an 8 in 10 chance of occurring)

and ‘‘***’’ very high confidence (greater than 9 in 10 chance of occurring). That convention is used throughout the Working Group II Fourth Assessment Report (AR4).

Table 19.1, the result of the process just described, follows:

173

174

175

176

177

178

The table explicitly lists criteria used by the Lead Authors to select candidates

for possible key vulnerabilities, as guidance to policy-makers on the process used.

Chapter 19 authors do not advise which vulnerabilities or impacts are ‘‘more important,’’ as that requires a value judgment and would be policy prescriptive. However,

explicitly showing the criteria in each case for our selection of potential key

vulnerabilities is intended to be helpful to stakeholders and policy-makers in their

own evaluations of what they may consider ‘‘key.’’ The Executive Summary of Chapter 19 summarizes the conclusions from Table 19.1 as follows:

General conclusions include [19.3]:

• Some observed key impacts have been at least partly attributed to anthropogenic climate change. Among these are increases in human mortality, loss of

glaciers, and increases in the frequency and/or intensity of extreme events.

• Global mean temperature changes of up to 2°C above 1990–2000 levels would

exacerbate current key impacts, such as those listed above (**), and trigger

others, such as reduced food security in many low-latitude nations (*). At the

same time, some systems such as global agricultural productivity, could benefit (o/*).

• Global mean temperature changes of 2 to 4 C above 1990–2000 levels would

result in an increasing number of key impacts at all scales (**), such as widespread loss of biodiversity, decreasing global agricultural productivity and

commitment to widespread deglaciation of Greenland (**) and West Antarctic

(*) ice sheets.

• Global mean temperature changes greater than 4°C above 1990–2000 levels

would lead to major increases in vulnerability (***), exceeding the adaptive

capacity of many systems (***).

• Regions that are already at high risk from observed climate variability and

climate change are more likely to be adversely affected in the near future due

to projected changes in climate and increases in the magnitude and/or frequency of already-damaging extreme events.

IV. Reasons for Concern.

The ‘‘reasons for concern’’ identified in the TAR remain a viable framework to consider key vulnerabilities. Recent research has updated some of the findings from the

TAR [19.3.7]:

• There is new and stronger evidence of observed impacts of climate change on

unique and vulnerable systems (such as polar and high-mountain communities and ecosystems), with increasing levels of adverse impacts as temperatures increase (***).

• There is new evidence that observed climate change has likely already increased the risk of certain extreme events such as heat waves, and it is more

likely than not that warming has contributed to intensification of some tropical cyclones with increasing levels of adverse impacts as temperatures increase (***).

• Distribution of impacts and vulnerabilities are still considered to be uneven,

and low-latitude less-developed areas are generally at greatest risk due to

both higher sensitivity and lower adaptive capacity, but there is new evidence

that vulnerability to climate change is also highly variable within countries,

including developed countries.

• There is some evidence that initial net market benefits from climate change

will peak at a lower magnitude and sooner than was assumed for the TAR,

and is likely that there will be higher damages for larger magnitudes of global mean temperature increases than estimated in the TAR.

• The literature offers more specific guidance on possible thresholds for initiating partial or near-complete deglaciation of Greenland and West Antarctica.

There is less confidence since the TAR in assessments of the risk of abrupt,

large scale changes to the Meridional Overturning Circulation (MOC).

V. The Potential Role of Adaptation.

Adaptation can significantly reduce many potentially dangerous impacts of climate change and reduce the risk of many key vulnerabilities. However, the technical, financial, and institutional capacity and the actual planning and implementation of effective adaptations is currently quite limited in many regions. In addition,

the risk-reducing potential of planned adaptation is either very limited or very costVerDate 11-MAY-2000 16:07 May 12, 2008 Jkt 032966 PO 00000 Frm 00068 Fmt 6601 Sfmt 6621 C:\WORKD\FULL07\020807\32966A.TXT SCIENCE1 PsN: SCIENCE1
179

ly for some key vulnerabilities, such as loss of biodiversity, melting of mountain glaciers or disintegration of major ice sheets. [19.4.1]

A general conclusion on the basis of the present understanding is that for market

and social systems there is considerable adaptation potential, but the economic costs

are potentially large, largely unknown and unequally distributed, as is the adaptation potential itself. For biological and geophysical systems the adaptation potential

is much less than in social and market systems. There is wide agreement that it

will be much more difficult for both human and natural systems to adapt to larger

magnitudes of global mean temperature change than to smaller ones, and that adaptation will be more difficult and/or costly for faster warming rates than slower

rates. [19.4.1]

VI. Potential Robust Conclusions.

Several conclusions appear robust across a diverse set of studies, in the integrated

assessment and mitigation literature [19.4.2; 19.4.3]:

• Given the uncertainties in factors such as climate sensitivity, regional climate

change, vulnerability to climate change, adaptive capacity and the likelihood

of bringing such capacity to bear, a risk management framework emerges as

a useful framework to address key vulnerabilities. However, the assignment

of probabilities to specific key impacts is often very difficult due to the large

uncertainties involved.

• Actions to mitigate climate change and reduce greenhouse gas emissions will

reduce the risk associated with most key vulnerabilities. Postponement of

such actions, in contrast, generally increases risks.

• Given the current atmospheric greenhouse gas concentrations (WG I SPM)

and the range of projections for future climate change, some key impacts (e.g.,

loss of species, partial deglaciation of major ice sheets), cannot be avoided

with high confidence. The probability of initiating some large-scale events is

very likely to continue to increase as long as greenhouse gas concentrations

and temperature continue to increase.

BIOGRAPHY FOR STEPHEN H. SCHNEIDER

Dr. Stephen H. Schneider is the Melvin and Joan Lane Professor for Interdisciplinary Environmental Studies, Professor of Biological Sciences, and Professor (by

courtesy) of Civil and Environmental Engineering. He is Co-Director of the Center

for Environmental Science and Policy in the Freeman Spogli Institute for International Studies and a Senior Fellow in the Woods Institute for the Environment

at Stanford University. Dr. Schneider received his Ph.D. in Mechanical Engineering

and Plasma Physics from Columbia University in 1971. He studied the role of greenhouse gases and suspended particulate material on climate as a postdoctoral fellow

at NASA’s Goddard Institute for Space Studies. He was awarded a postdoctoral fellowship at the National Center for Atmospheric Research in 1972 and was a member of the scientific staff of NCAR from 1973–1996, where he co-founded the Climate

Project.

Dr. Schneider focuses on climate change science, integrated assessment of ecological and economic impacts of human-induced climate change, and identifying viable

climate policies and technological solutions. He has consulted with federal agencies

and/or White House staff in the Nixon, Carter, Reagan, Clinton, and two Bush administrations.

Actively involved with the IPCC (Intergovernmental Panel on Climate Change),

an initiative of the United Nations Environment Program and the World Meteorological Organization since its origin in 1988, he is currently a Coordinating Lead

Author of Working Group II Chapter 19, ‘‘Assessing Key Vulnerabilities and the Risk

from Climate Change,’’ as well as contributing to the Synthesis Report, which synthesizes the contributions of Working Groups I, II, and III, for the Fourth Assessment Report (AR4) to be published in 2007. AR4 will be used by governments worldwide as the definitive document regarding climate change science, impacts, adaptation, vulnerability, and mitigation until 2012.

In 1991, Dr. Schneider was awarded the American Association for the Advancement of Science/ Westinghouse Award for Public Understanding of Science and

Technology for furthering public understanding of environmental science and its implications for public policy. In 1992, he was honored with a MacArthur Fellowship

for his ability to integrate and interpret the results of global climate research

through public lectures, classroom teaching, environmental assessment committees,

media appearances, Congressional testimony and research collaboration with colleagues. Dr. Schneider was elected to membership in the U.S. National Academy of

180

Sciences in April 2002. He received the Edward T. Law Roe Award of the Society

of Conservation Biology in 2003. He and his spouse-collaborator, Terry Root, jointly

received the National Conservation Achievement Award from the National Wildlife

Federation in 2003 and the Banksia Foundation’s International Environmental

Award in 2006 in Australia.

Dr. Schneider is founder and Editor of the interdisciplinary journal, Climate

Change. Editor-in-Chief of the Encyclopedia of Climate and Weather and author of

The Genesis Strategy: Climate and Global Survival; Global Warming: Are We Entering the Greenhouse Century? and Laboratory Earth: The Planetary Gamble We Can’t

Afford to Lose. In addition, he has authored or co-authored over 300 scientific papers, proceedings, legislative testimonies, edited books and book chapters, and some

115 book reviews, editorials and popularizations.

Dr. Schneider teaches undergraduate and graduate courses in Earth Systems,

Human Biology, Civil Engineering, Biological Sciences, the Senior Honors Seminar

in Environmental Science, Technology and Policy, and the Interdisciplinary Graduate Program in Environment and Resources, as well as guides the work of Ph.D.

candidates, post-doctoral scholars, and other researchers.

Currently, Dr. Schneider is counseling policy-makers about the importance of

using risk management strategies in climate-policy decision-making, given the uncertainties in future projections of global climate change. In addition to continuing

to serve as an advisor to decision-makers, he consults with corporate executives and

other stakeholders in industry and the nonprofit sectors regarding possible climaterelated events and is actively engaged in improving public understanding of science

and the environment through extensive media communication and public outreach.

DISCUSSION

DANGEROUS ANTHROPOGENIC INTERFERENCE

Chairman GORDON. Thank you, Dr. Schneider.

At this point we will have our questions, and I will open the

questions with recognizing myself, the Chairman, for five minutes.

Could you put back up one of Dr. Schneider’s exhibits, please?

Any one of them would be fine.

Dr. Schneider, I noticed that there are some red and some black

statements. How are those distinguished?

Dr. SCHNEIDER. Well, I put in red those things to call to the

Committee’s attention in short testimony. The identification of potential key vulnerabilities was designed to provide guidance to decision-makers on the levels and rates of climate change that might

be associated with Dangerous Anthropogenic Interference, or DAI,

which is exactly the terminology of the U.N. Framework Convention, and I will remind those here, some may not remember, back

to 1992 at the Rio meeting that that was signed by President Bush

at the time and ratified by the U.S. Senate, so this is in fact the

law of the land and the second-most signed treaty, I believe, in

world history. But the most important sentence is the one below

that which is ultimately the definition of DAI, Dangerous Anthropogenic Interference, cannot be based on scientific arguments alone

but involves other judgments informed by the state of scientific

knowledge and that no single metric can adequately describe the

diversity of these vulnerabilities nor determine the ranking. We got

over 1,000 review comments and that was I think our most praised

comment because we were open and forthright in saying that judgments have to be made by individual decision-makers on their own

criteria and it is not our job to give you the answers.

181

POTENTIAL MITIGATION OF CLIMATE CHANGE

Chairman GORDON. Thank you, Dr. Schneider. Have we reached

the point yet where scientists believe there is some impacts of climate change that cannot be aborted even with aggressive mitigation?

Dr. SCHNEIDER. Yes. I think that in Working Group I, it is very

clear that the 0.75 degrees Celsius, something like 1.34 degrees

Fahrenheit, warming since the Industrial Revolution, we can’t roll

that one back, and the probability that we will be able to hold the

line on current emissions is very, very low, given world development patterns, and that we are committed to at least another degree or two of warming at best and at worst I believe their top

number was 6.4 degrees by the 2090s.

CLIMATE CHANGE IMPACTS

Chairman GORDON. And the Pentagon released a study that discussed the possible security risks caused by climate change. What

risks do you see associated with climate change?

Dr. SCHNEIDER. Well, I think that the risks as we stated in our

chapter are those people already most vulnerable, which tend to be

poorer people living in hot countries, people living in Hurricane

Alley and high mountains where glaciers are melting, in the Arctic,

Mediterranean, climates like California or the Mediterranean, they

are the highest risk of natural climate variability, and if you add

on top of that additional components of stress from human activities, they are the first groups to be feeling the effects. The only

groups that would feel them even more severely would be natural

systems species because they don’t have the conscious adaptive capacity to put in irrigation systems to deal with their plight. They

either can move or they can’t, and those kinds of issues I believe

are the ones that are most serious, and what the Pentagon was

stressing is that in areas where human behavior and political situation have already created a stress situation, an additional stress

on top of that could be a tipping point. I believe that was the sense

in which they were concerned about climate on top of everything

else.

ANTHROPOGENIC CAUSES OF CLIMATE CHANGE

Chairman GORDON. Thank you, Dr. Schneider. Let me just conclude with a question for everyone, and I want you to feel no

qualms about disagreeing if I am not stating or summarizing the

overall report. I am going to repeat to you what I got from it.

Again, correct me I am wrong. I understand that we have observed

evidence that global warming driven by human activities is having

an actual impact on physical and biological systems. Is that true?

A lot of vertical nods.

Dr. ROSENZWEIG. Yes, that is true.

Chairman GORDON. If you don’t agree, please raise your hand because I want to get this on the record. The impacts are mixed,

some beneficial and some negative, but without taking steps to

adapt climate change and to mitigate greenhouse gas emissions,

impacts will tend to be more negative than positive and this trend

will get worse over time. We are going to experience climate change

182

for several decades no matter what we do, but this assessment suggests that if we take action now to reduce greenhouse gas emissions, we can abort or at least delay more-severe impacts on climate change in the future. Is that true? All vertical nods. All right.

So we need policies that promote both adaptation and mitigation.

We need adaptation strategies to cope with current and near-term

climate change impacts. We need mitigation strategies to adapt

and to further future impacts so great that adaptation will not be

sufficient to cope with the mitigation or with the magnitude of

some projected changes. Have I gotten the thrust of this report correct?

Dr. SCHNEIDER. That is correct.

Chairman GORDON. Thank you very much. Again, thank you for

your time, and I yield to Dr. Ehlers for five minutes.

Dr. SCHNEIDER. With that, Mr. Chairman, we wish we had you

as a lead author on our report. It is very succinct and accurate.

Dr. ROSENZWEIG. Or in Brussels.

Mr. EHLERS. Thank you, Mr. Chairman. With that succinct summary, I am not sure we need to ask any more questions.

First of all, Dr. Pulwarty, your emphasis in your comments here

was almost entirely on management——

Dr. PULWARTY. Yes.

Mr. EHLERS.—and adaptation. Does this mean you and the panel

have basically given up on the hope of reining in CO2 or methane

emissions?

Dr. PULWARTY. No. The response is geared towards the chapters

that we were actually tasked with writing. As was stated in the

earlier comments, I think the combination of mitigation and adaptation is necessary. The management components become very important in the near-term because of the commitment that we already have in the system with CO2—excessive CO2 already in the

atmosphere. So for us, it is not necessary a tradeoff but a twopronged activity. One of the things that the adaptation focus helps

us with is to imbed both natural climate variability and climate

change in an integrated response to dealing with climatic risks. So

both are still important and still equally important.

CLIMATE CHANGE IMPACTS: DROUGHT

Mr. EHLERS. Thank you.

Dr. Agrawala and Dr. Pulwarty both, you talked about, or the report predicts, that drought-affected areas will increase, and I am

curious, what parts of the U.S. are vulnerable to this? I participated in a conference on this last year where I spoke and one of

the authors suggested that if at current trends and some time in

the next 50 or 75 years, Indiana would look like Texas, which is

a horrible fate. I can say that since Mr. Hall has left. But is there

any basis for that? Can we expect the great breadbasket of the

world, the Midwest, to actually begin suffering from drought?

Dr. PULWARTY. One of the things we can definitely point to is a

trend in drying within the Colorado River basin and that is very

clear, and reduction in Great Lake levels as well. What I would

like to do is ask Dr. Easterling, who focuses heavily on agriculture,

if he would be willing to address your question.

Mr. EHLERS. Dr. Easterling?

183

Dr. EASTERLING. It is very clear from the accumulating evidence

that the western third of the Nation dries, and if one look at an

agriculturally meaningful quantity like runoff, that runoff projections under climate change out into the 21st century show a decline

throughout most of the significant irrigated agricultural production

areas of the country, especially the western Great Plains. I need

not point out that we are already seeing declining groundwater levels just through normal irrigation water use and we would expect

that to intensify under climate change.

Mr. EHLERS. When you say the western one-third, you are basically talking the Rockies westward, right?

Dr. EASTERLING. Well, if one looks at the numbers and of course

they are never totally precise where you draw the boundaries but

it appears to us that the Great Plains, western Great Plains would

be involved in this general drying trend.

Mr. EHLERS. They are also facing exhaustion of the reservoir as

well.

Dr. EASTERLING. Correct.

Mr. EHLERS. So if we own property in Nebraska or Kansas, we

should sell.

Dr. EASTERLING. Or change to something else.

Mr. EHLERS. What about Indiana, the eastern Great Plains?

Dr. EASTERLING. Well, there may be opportunities to engage in

irrigation in the middle or central to eastern parts of the Corn Belt

but I think the studies are yet to have been done to give us compelling evidence that that is a viable option, increased irrigation in

those areas.

CLIMATE CHANGE IMPACTS: THE GREAT LAKES

Mr. EHLERS. Thank you.

Dr. Burkett, you talked about coastal erosion issues and so forth

and I agree with your concern there. I spent a few days on the

eastern coast of the Chesapeake for a retreat recently and I was

just astounded at how only a few feet rise would inundate that entire area. But being from the Great Lakes, I am concerned about

how does all of this impact the Great Lakes in the United States?

Someone mentioned earlier they had gone down. It is hard to know

whether that is attributable to climate change or not. Do you anticipate any changes in the Great Lakes, the rainfall of course

could affect it, but any other comments?

Dr. BURKETT. It was not included in our coastal chapter and I

think perhaps Roger can answer that better than me.

Mr. EHLERS. Okay.

Dr. PULWARTY. One of the major issues regarding the Great

Lakes has to do with increasing temperatures as it relates to evaporation, and so the link between temperature impact on snow that

runs off into the Great Lakes and evaporation on the Great Lakes

themselves are really where the signal for future lowering of lake

levels is coming from.

Mr. EHLERS. All right. Thank you very much, Mr. Chairman.

Chairman GORDON. I noticed that Dr. Ehlers didn’t ask if any

State was going to wind up looking like Michigan.

Mr. EHLERS. There can be no equal.

Mr. GORDON. Dr. Baird is recognized.

184

CARBON SINKS

Mr. BAIRD. I thank the Chair. I thank our outstanding witnesses

for their testimony.

Dr. Easterling, I come from a heavy forested State, and you

talked predominantly about, as I followed your testimony about the

impact of growth rates on agriculture. Can you talk a little bit

about carbon sinking, particularly in forest products and the role

that forests may or may not play as they sink for carbon. Did the

group study that at all?

Dr. EASTERLING. That was peripherally considered partly because

our chapter was really focusing on wood products and the productivity of the timber industry, but I will say that we would anticipate, based on our studies, in the early stages of the warming a

positive effect on timber productivity in the higher latitudes. That

would include of course the United States. And as the warming

progresses out into the 21st century, that advantage to the higher

latitudes grows stronger and we actually then begin to start to see

the tropical latitudes lose advantage so that from a competitive

standpoint, the higher latitudes and the timber industries may relatively be advantaged. Ipso facto, one would expect that as significant carbon sinks, particularly for young, managed forests, that we

could see great potential for sequestering carbon. Of course, that

potential will saturate at some point when we satisfy world demand for timber and any additional growth would be natural ecosystem growth and I am not qualified to comment on that part.

Mr. BAIRD. I appreciate that. One of the things we have been

looking at in my region is what happens after a fire, and one option

is to harvest the trees and sink the carbon in what we call houses.

Another option is to leave the trees there to reburn and be eaten

by bugs, et cetera, which will put more carbon into the air. In a

rather ironic twist, the ‘‘environmental community’’ has opposed

the harvesting of burned trees, preferring to leave them standing

in a perfectly good woods, sit there and rot and decay and secondburn and produce all that carbon into the air. I kind of think it

would be better to sink them myself and plant some new trees and

grow a forest up, but that is a controversy for another day.

Dr. Rosenzweig, you look like you might have a comment on this.

Dr. ROSENZWEIG. I was just going to comment that observed effects of temperature increases already have shown alterations in

disturbance regimens such as fire and pests, as you just mentioned,

so temperature increases are already having an effect on mid-latitude and high-latitude forests.

IMPACTS ON THE FISHING INDUSTRY

Mr. BAIRD. We see larger and larger areas of acreage burn virtually every year. It is just a pretty steady increase and we see bug

infestation, which some of us would also like to address, and again,

I think there are significant carbon issues there and at some point

I would be very interested if any of you have insights into somebody who might be able to give insights into the relative pros and

cons of leaving burnt timber to stand or to harvest it and sink it,

I would sure appreciate it.

185

None of you talked at all about—I know we have a limited-sized

panel here but no one spoke about the impacts of fishing, which for

our coastal and Michigan communities as well is pretty important.

Any insights from the IPCC report on the impacts of fishing or

aquaculture, commercial or recreational?

Dr. BURKETT. In terms of fishing impacts on coastal systems,

most of the marine fisheries and coastal fisheries are estuarine-dependent, and tied to carbon export from the wetlands, particularly

in the South Atlantic and Gulf regions. You know, that is what determines fisheries’ productivity, and so as the wetlands go, as the

coast goes, so goes the fisheries in general.

Mr. BAIRD. So the premise both on the nutrient and on the habitat and a rearing kind of situation, you might see a decline in there

because you have lost the areas for saturation?

Dr. BURKETT. Right, and initially you might have a boost in productivity because of the declining material going into the estuary.

Ms. BAIRD. I see.

Dr. Pulwarty.

Dr. PULWARTY. There is also a related impact on in-stream temperature and decline of salmon and trout fishing and so on.

Mr. BAIRD. Dr. Schneider.

Dr. SCHNEIDER. Thank you. Some fish might be able to—the

warm fish might be able to replace cold fish so it might not be easy

for the grandfather to teach the grandchildren to fish precisely the

same species. One hopes that at least there will be some replacement. But the one area where there seems to be greater concern,

a little less relevant to the United States but certainly relevant to

the world is the threat to coral reefs through a combination of increasing temperature and in fact that is one of the lowest thresholds, one to two degrees additional warming in Celsius leading to

extensive bleaching beyond that extensive death of corals and those

coral areas are a great breeding ground for fish of all kinds and

that is further exacerbated if really do double and triple carbon dioxide. That makes the oceans more acidic, which would be a threat

again to any calcite-shell creatures including corals. So that would

have a significant impact on fisheries on a planetary scale, given

the incredible importance of reefs as breeding sites.

Mr. BAIRD. Thank you, Dr. Schneider. I witnessed this personally

some years ago, not that long ago, about five years ago, the

Maldives Islands, where they had had, if I remember correctly,

about a 90-degree—it is amazing to think of ocean temperature at

90 degrees for about three weeks long and it basically wiped out

90 percent of the coral and it was really tragic to see what was

once magnificent coral zone basically looking like gray hulks of

dusty debris.

Chairman GORDON. The gentleman’s time has——

Dr. SCHNEIDER. I was just going to say that in fact that these

are all part of a natural variability, El Nin ̃ o and other such things,

so people think well, it is normal and they will recover. The problem is when these fluctuations which can cause bleaching occur

with a decreasing time between them, which is exactly what happens on the rising tide of overall warming, then what you do is, you

don’t give the reef enough time to recover naturally and that is preVerDate 11-MAY-2000 16:07 May 12, 2008 Jkt 032966 PO 00000 Frm 00075 Fmt 6601 Sfmt 6601 C:\WORKD\FULL07\020807\32966A.TXT SCIENCE1 PsN: SCIENCE1
186

cisely how global warming would interact with the natural variability and threaten those natural systems.

Chairman GORDON. The gentleman’s time has expired. I understand that Chairman Boehlert took a group to the South Pole in

his last term and they stopped at the Great Barrier Reef on the

way and they saw firsthand, as reported to me, that it was very

visible that that reef was dying.

Dr. Bartlett is recognized for five minutes.

ENERGY CONCERNS

Mr. BARTLETT. Thank you very much. Thank you for your testimony. The world faces a simultaneous interaction of two multi-decades-long tsunamis. One we have been talking about today, global

warming, and the subsequent climate changes. The second is reflected in two articles that appeared recently. Just a few days ago

in the Wall Street Journal was a front-page article that noted that

the world’s second-largest oil field, Canteral in Mexico, had declined in production 20 percent in the last two years. About three

weeks ago, there was an article in the Washington Post, unfortunately not on the first page, where its importance should have

placed it, which was talking about corn ethanol production. As you

know, we produce relatively insignificant amounts of corn ethanol

in terms of replacing gasoline but it has doubled the price of corn

and tortillas are more expensive and Mexicans are hungry and my

dairy farmers are going bankrupt because the price of feed for cows

is up. This article noted that if we use all of our corn land for ethanol, we have fed no animals and no tortillas for us, and if you discounted that ethanol production for the contribution of fossil fuels,

which the authors of the article said was 80 percent—I generally

use 75 percent to be generous—that it would replace but 2.4 percent of our gasoline. That is all of our corn made into ethanol, and

the authors noted that you could displace as much gasoline if you

simply tuned up your car and put adequate air in the tires. These

two articles of course are referring to the coming critical energy

shortage in the world. Peak oil is a phenomenon which more and

more folks are now focusing on, and of course, the shortage of these

more readily available fossil fuels is going to result in increased

use of coal, which in terms of the CO2 production is really a very

bad actor as you convert the coal to liquids and to gases.

Did you in any of your deliberations consider the simultaneous

interaction of these two forces? I noticed one of your chapters dealt

with adaptation practices, options, constraints and capacities. Did

you just assume that we are going to have the present availability

of energy? Isn’t it very probable that the impacts of climate change

are going to really be exacerbated by energy shortages and high

prices? Yes, sir?

Dr. EASTERLING. To be sure, the issue of energy in agriculture

and food production is huge and this was a growing concern. The

rising prices for energy as we began the IPCC, it became very clear

that as we looked out at the adaptation possibilities for food production that there would be this growing competition between food

and energy, bioenergy. Although our task was not to analyze the

energetics of bioenergy,. I will say that several of our authors have

commented that it is not likely the energetics of using corn grain

187

for ethanol will ever make sense and that as a placeholder for the

use of cellulosic conversion to bioenergy. That is, using some grain

but also using the other parts of the plant, the stover, plus also

bringing into production woody products, wood chips, that makes

eminent sense going forward but this is all outside of the central

task of the IPCC. It will have to be a topic we consider in the next

round.

Mr. BARTLETT. On the 14th day of next month will be the 50th

anniversary of a speech given by Hyman Rickover at St. Paul of

Minnesota to—one of you is nodding your head. You have read the

speech. I would encourage you to do a Google search for Rickover

and energy and that will pop up. You will find it a very revealing,

very prophetic discussion. He suggested that competition for food

and fuel would result in scarcities of food for people.

Thank you very much, Mr. Chairman.

Chairman GORDON. Thank you. The gentleman’s time has expired.

Ms. Woolsey is recognized for five minutes.

INTERNATIONAL EFFORTS

Ms. WOOLSEY. Thank you, Mr. Chairman, and thank you to the

witnesses. I would actually like to say that each one of these witnesses could be a hearing in and of and the topics in and of itself.

Thank you.

Certainly we heard from all of you that global warming is a huge

concern and I am hearing also, and I don’t think that the Chairman asked you to nod your head on this, that it is not only a concern in the United States, it is a concern worldwide. Dr. Baird and

I just returned—well, we spent the first week of the Easter break

in China at a U.S./China relations conference and we started out

in Shanghai where there is more high rises than any other city in

the entire world and you can’t breathe. I was struck by the development in China and the atmosphere and the environment. I took

my all-American football player son with me. He got a nosebleed.

My eyes got all red. We could not drink the water in the six-star

hotel in our rooms. I mean, give me a break.

So in our conference I asked the question of the Chinese Government representatives the question of global warming and that discussion got going, and the Chinese Government representative’s response was, well, the United States has used up, you know, more

than their share with four percent of the population and 25 percent

of the use of resources and probably equal amount of pollution,

their share, now it is our turn. Well, of course that doesn’t work,

you know. There is no time for that turn and so of course we talked

about that.

So my question to you is, where do you see the international effort, where is the United States’ responsibility because we do have

some making up to do? I mean, we certainly used more than our

share, stressed natural systems, et cetera. A word you never used

was ‘‘greed’’ and it all comes into play, and if you would like to respond, I would certainly like to hear it, of how much more can we

do, how much does the international population world, what do we

have to do and how fast do we need to be doing it?

188

Dr. SCHNEIDER. Well, I will take a shot at it, but this is not directly in the purview of the IPCC so I will respond personally. I

have been a veteran of many, many such international meetings

and I can report on what I have seen and how I interpret it for

you in this connection. When you go to international meetings,

typically the conference of the parties, you hear exactly what you

said, Congresswoman Woolsey. You see blame. You will hear developed counties pointing out about corruption, lack of markets, insufficient development, overpopulation, pointing fingers toward the developing world and then you will hear from the developing world

a legacy of colonialism, market share interference and an absolute

greedy reluctance to give up any measure of your consumption. Of

course, they are both right and the question is, if you are going to

deal with the problem which is a commons problem where it is the

collective integration of all of our individual actions, national, State

and federal actions which create the problem, then we have to have

cooperative solutions and cooperative solutions involve deals. They

involve win-wins, and in the case of the international one, my view

of that is, yes, we have a right to ask China and India not to hold

the sustainability agenda of the planet hostage to their notion of

the inequity of their development, but they also have a right to ask

us to help them with that process since we are a factor of 10 per

capita more consumptive than they are. So rather than blame,

making deals where we get public-private partnerships with international backing to try to help invest our way out of it, not just

here but also there, and then the ones who are cleverest enough

in the invention also have partial ownership in the patents. You

then start to be able to approach the problem but it is very difficult

to have that kind of cooperation until people trust each other which

is why it is so important to have international cooperation, and

countries that created most of the problem, which unfortunately 80

percent of the emissions accumulated are from the 20 percent of

the richest countries, we do have to take initial steps that will be

stronger and more costly than other countries or we have no credibility. But your point is completely right. We can solve it together

if and only if we can cooperate.

Ms. WOOLSEY. Dr. Rosenzweig.

Dr. ROSENZWEIG. I would like to comment on the IPCC scientists’

part of this, that in the testimony that I read, one of our lead authors was a Chinese woman hydrologist, so the effects that I read

about, the changes in the rivers, came directly from her and so I

believe that working together as scientists is one way of establishing the cooperation that is needed to go forward on the issue.

Chairman GORDON. Thank you. The gentlelady’s time has expired, unless somebody feels—Dr. Easterling?

Dr. EASTERLING. I wanted to respond just in the context of food

security. The United States has been the supplier of last resort of

food for decades and it is clear to us as I showed in the differences

between the tropics and the mid-latitudes that there will have to

be some movement of food across large areas through trade. I

would not advocate a system of food aid per se but I think the U.S.

will have an obligation to facilitate the relatively unrestricted

movement of food and fibre into those regions that need it the most

and to do it in a way in which the local farmers are not so disVerDate 11-MAY-2000 16:07 May 12, 2008 Jkt 032966 PO 00000 Frm 00078 Fmt 6601 Sfmt 6601 C:\WORKD\FULL07\020807\32966A.TXT SCIENCE1 PsN: SCIENCE1
189

advantaged by the trade that the internal capacity, the domestic

capacity in African countries, for example, is not greatly diminished.

Chairman GORDON. The gentlelady’s time has expired, and I will

tell the gentlelady, we are looking at a hearing to go more into this

specifically in the near future.

Dr. Gingrey is recognized.

ADAPTATION AND MITIGATION STRATEGIES

Mr. GINGREY. Mr. Chairman, I thank you. As I sit here and listen to this somewhat doomsday scenario, I turn to my friend on my

right from California and I told him that not all is bad. One of

these days maybe he will be surfing off the West Coast of Georgia.

But I thought, Dr. Schneider, your response to Lynn Woolsey’s

question was the most succinct summary that I have heard in regard to this overall issue of science and policy, and although I don’t

think you get too many naysayers in regard to the science on this

committee on either side of the aisle, either the Majority or the Minority Members, clearly at some point and some point soon we are

going to have to address the science with sound policy. So that is

why I am so appreciative, Dr. Schneider, of your remarks.

I want to address my question though to Dr. Agrawala, our

friend from Paris by way of Princeton, because you talked about

adaptation and I think a lot of your testimony dealt with that. It

really seems to me that this Working Group II has spent a lot of

time in the testimony of all six of you in regard to adaptation

versus mitigation. I would like for you to maybe start with Dr.

Agrawala in giving us some examples of how adaptation might

work versus mitigation and what the relative cost-benefit ratio. I

am thinking of course in terms of the early 19th century, or early

1900s, I should say, 20th century, when the automobile came along

with Henry Ford, and what did people do with the horse and

buggies. Well, clearly the Federal Government did not have to force

them out of those horse and buggies. They adapted. It seems to me

that, you know, there is great potential for adaptation. There is

also need for some mitigation but striking that balance, so if you

would address that for us, Doctor.

Dr. AGRAWALA. Thank you, Congressman. You are absolutely

right. There is great potential for adaptation. I think one of the key

messages from our chapter and indeed the entire Working Group

II report is that we need both mitigation and adaptation. What we

do in mitigation now will have impacts on the climate system only

in several decades so there are a number of near-term impacts of

climate change we already committed to and there is no option but

to adapt to them. At the same time, adapting to unmitigated climate change over the long-term would be beyond the possibility of

many systems, both natural systems and human systems. So we

need a portfolio of responses which encompass both mitigation and

adaptation. You are also right in saying that a lot of adaptation

would happen autonomously. When people are faced with changes

and different risks, they take a number of decisions, and our chapter actually documents a number of examples where a number of

actors have taken observed changes in climate change as well as

scenarios for future changes into account. There are examples, for

190

example, of infrastructure projects. The Copenhagen Metro was

built higher to take future sea-level rise into account. But at this

time these examples are really boutique examples. You can literally

document all the examples where future changes are taken into account in a couple of pages. And what we need to do is scale up

these examples and have many more of them. The problem we run

into is that even though there is wide familiarity with the seriousness of climate change and the impacts, we still don’t have specific

information for particular users to take those concerns into account

when they make decisions. The questions from users are often,

what is going to happen to my farm plot or my watershed or my

city? We need information at that level of detail and that is one of

the key issues I think where government policy and scientific research can play an important role.

Just a quick word about the costs. The costs of mitigation were

not covered by the Working Group II report. The Working Group

III report will be discussing this in a month’s time. We did try to

look at what we know about the costs of adaptation and our knowledge remains very limited. I gave you a range, which is nothing

more than a back-of-envelope calculation by the World Bank saying

that the total costs of adaptation globally could be between $10 and

$40 billion per year. I wouldn’t take those numbers to heart but it

does show that there might be significant costs associated with it.

We need a lot more research on this particular issue. Some of the

research that has been done on cost has been on infrastructure adaptation, what would it cost to build a sea wall, for example, and

that can be answered. But what has not been addressed is what

are the costs of policies, what are the costs of implementation, and

if it takes certain adaptation measures, what might be the spillover

effects on other actors, and I think clearly a lot of work is needed

before we can come to grips with this question.

Chairman GORDON. The gentleman’s time has expired.

Mr. GINGREY. Thank you, Mr. Chairman.

Chairman GORDON. If you have something else, you need to go

forward but otherwise——

Mr. GINGREY. No, Mr. Chairman, I am fine. I know one of the

panel wanted to also weigh in but I am fine——

Chairman GORDON. Go right ahead.

Dr. ROSENZWEIG. I think it is important to realize that adaptation and mitigation are not always opposite. They are not always

on opposite sides of the fence. There are actions that can do both.

I will give two examples. In cities, having green roofs, vegetative

roofs on cities, cool the people below in the buildings. That is an

adaptation. At the same time, they reduce their air conditioning

costs in the summer. That is a mitigation. So there can be

synergies. One more from agriculture. Carbon sequestration in

farmers’ fields. This is mitigation in terms of sequestering the carbon, reducing atmospheric concentrations of carbon dioxide but, at

the same time when we have higher organic matter in our farmers’

fields, those farmers can then withstand both droughts and floods

better. So while of course there are key issues to consider as we

consider them separately, I think it is also important to realize

that sometimes, and this is in the chapter, I believe—there was a

191

chapter actually on adaptation and mitigation. There are times

when they can be synergistic.

Chairman GORDON. Thank you. Dr. McNerney.

CLIMATE CHANGE IMPACTS: AGRICULTURE

Mr. MCNERNEY. Thank you, Mr. Chairman.

I would like to thank the panel for taking time to come up here

and for your excellent and informative testimony. I have some detailed questions.

Dr. Easterling, what sort of—what are the sort of adaptations

that you envision to prevent crop loss from occurring with rising

temperatures? You mentioned that, and I wasn’t sure what you

were referring to exactly there.

Dr. EASTERLING. Well, one of the certainties we think of warming

is that farmers will have the opportunity anywhere they grow their

crops in this country to alter the planting dates to take advantage

of the earlier spring warm-up. They can at the same time alter the

types of crop varieties that they plant because not all crops are the

same in terms of how long it takes for them to reach maturity, and

there are some maturity classes that are able to handle the longer

growing seasons that are likely to occur. In fact, we are already,

as Dr. Rosenzweig noted in her chapter, starting to see increasing

lengths of growing seasons, that these would be natural, easy-toapply adaptations that no one would have to tell farmers how to

do it.

CLIMATE CHANGE IMPACTS: WATER AVAILABILITY

Mr. MCNERNEY. Thank you. That doesn’t sound that bad then.

There is a question for Dr. Pulwarty. I am from Northern California and much of the delta is in my district. You referred to the

inability of the delta to provide the water that is required by about

the year 2020. What specific mechanisms are involved in that in

your mind? And you mentioned the partnership with water planners would help in adaptation. Could you give us some details?

Dr. PULWARTY. Certainty. From the basis of the last set of discussions that we have been hearing, there is investigated efficiency

criteria in terms of how we use water that can actually be introduced. In many areas we have got more efficient technology for

using water for irrigation. That does not reduce the quality of life

in implementation. For the standpoint of the Sacramento-San Joaquin basin, one of the major signals that we are seeing there is increased early runoff of snow and a declining snowpack. That trend,

given current rates of extraction of water and that trend in temperature, the estimates are that by 2020 the system and the Colorado River basin as well would not be able to meet its demands.

So from the standpoint of adaptations and response, there are

water banking mechanisms, water tradability and water rights for

purchasing. The key question that is there is a lesson out of the

drought of 1987 to 1992 in which a water bank was set up. It was

a very successful water bank. But the place that the excess water

for the bank came from was from the environment. We have to ask

whether or not the adaptation mechanisms that we have are in fact

viable under the conditions of the climate change and variability.

192

So we have learned to do some things better, there is no question

about that, and water banking is one of them.

I do want to mention relative to that that in terms of efficient

water technology, there is a huge emerging market in developing

adaptation technology in which we could be engaged.

Mr. MCNERNEY. Thank you. I yield back.

Chairman GORDON. Thank you. I will now ask our panel to buckle up and recognize Mr. Rohrabacher for five minutes.

Mr. ROHRABACHER. Thank you very much, Mr. Chairman. Let me

just note that it is really important that we have such discussions

as today. However, let me lament that much of the discussion

about global warming has been controlled and skewed in favor of

alarmists’ predictions. We have been, for example, treated to the

predictions of gloom and doom that are based essentially on extending trend lines so far out that it becomes totally scientifically

indefensible. You would say well, this trend over the number of

years will mean in this—in another 150 years that this is what it

is going to be. I would like to submit for the record an article by

Richard Lindzen, who is a distinguished Professor at MIT. [See Appendix 2: Additional Material for the Record.] Unfortunately, this

Newsweek article—I wouldn’t even know about it if I was an American citizen because it made it into the international edition of

Newsweek but didn’t seem to make it into the national edition of

Newsweek. In this article, he says there is no compelling evidence

that the worrying trend seen will amount to anything close to the

catastrophe being predicted. The Earth is always warming or cooling as much as 2/10 of a degree in a year and the periods of contrast of the average temperature are rare. Current alarm rests on

the false assumption that not only are we living in the perfect

world of temperatures but also that our warming forecasts for the

year 2040 are somehow more realistic than the weatherman’s forecast for next week. And let me note that this is a distinguished

Professor from MIT. There are many such Professors who are totally dismissed, and as I say, this didn’t make it into the American

edition. I just happened to be flying back from Europe yesterday

and I read this. In the same edition, there is an article about a

study, Mr. Chairman, a very well-financed study that indicates

that we should be chopping down all of the trees in the world in

order to combat global warming. The effect of chopping every tree

would actually, and this is a scientific study, that would actually

then give us a cooler situation than if we left all the trees up. Now,

again, I will submit for the record when I find it. I just have to look

this up on the Internet.

There are also many quotes that I will put into the record at this

point of highly respected scientists, and in terms of today’s hearing

we have a quote from Heindrich, and I don’t know how to pronounce his last name——

Dr. SCHNEIDER. Tenecus.

Mr. ROHRABACHER. Yes, a former Director of Research for the

Royal Dutch Meteorological Institute and Professor of Aeronautical

Engineering at Penn State in which he states, ‘‘I protect the overwhelming pressure to adhere to the climate change dogma promoted by the adherence of the IPCC.’’ So let us get a little of this

on the record as part of the discussion. I think it is really imporVerDate 11-MAY-2000 16:07 May 12, 2008 Jkt 032966 PO 00000 Frm 00082 Fmt 6601 Sfmt 6601 C:\WORKD\FULL07\020807\32966A.TXT SCIENCE1 PsN: SCIENCE1
193

tant for us to have an honest and a broad-ranging discussion rather than a controlled discussion of this issue. The last time we had

a hearing and I mentioned that perhaps dinosaur flatulence must

have caused the first cycle of global warming, totally in jest, actually making fun of the position. People say we can control animal

flatulence today and that is the way we are going to prevent global

warming. In fact, it was widely reported in the press that I was

serious about that, which indicates the people reporting it, controlling the public discussion are either dishonest or incompetent.

So with that, let me ask a couple questions of this panel. You

know, it was really cold when I landed here. It was cold, and I was

wondering, in recent years has it been getting warmer or colder,

the last five, six years? What is the temperature? Should I pull out

somebody else to tell you that the studies are indicating that it is

actually getting cooler in the last six or seven years.

Chairman GORDON. I think the panel can answer that by repeating what 113 countries including the United States said at the last

IPCC report. Would any member of the panel like to do that?

Mr. ROHRABACHER. Is it getting warmer or cooler in the last five

years?

Dr. SCHNEIDER. On a global scale, it is harder to see a trend in

five years.

Mr. ROHRABACHER. I didn’t ask about the trend. I said, is it getting warmer or cooler?

Dr. SCHNEIDER. No climate scientist would discuss climate in a

time frame much less than many decades so therefore we wouldn’t

look at what happens in five years, we would look at it over a period of——

Mr. ROHRABACHER. So I take it, it is getting cooler?

Dr. SCHNEIDER. I think it is irrelevant.

Mr. ROHRABACHER. Sir, I take it from your answer it is getting

cooler because every time I ask a pointed question that seems to

go in the other direction, we get this, you know, juggling act of trying not to answer the question. Let me note that even on the chart

that I have been presented by the so-called experts, we see that the

global warming of 1.5 degrees has taken place over 150 years starting in 1850. Let us also note that 1850 reflects something else. It

reflects the bottom end of a 300-year decline in the Earth’s temperatures by these very same people who have tried to reach out

to find out what the temperature was in the past or what it would

be in the future. You don’t start off a trend line at the very bottom

of a decline and say that this is the average that we are going to

face into the hundreds of years in the future. Well, a lot of things

like this that tend to let me not to suggest that there isn’t some

warming going on because there obviously is warming going on.

The question is whether it is man-made is another question now

that we know that NASA has given us reports of the warming that

is taking place on Mars and other planets. That would suggest to

me that if there is some warming, it may be due to sunspots more

than it does to human activity. And if human activity ends up trying to control our lives, it will be in a way that prevents industrialization, et cetera. We are going to pay a severe price for this type

of alarmism. One last question, if I could get it out here, is about

these predictions and I guess I should just leave it at that.

194

Chairman GORDON. Well, the gentleman’s time more than went

over but I thought that it was important to let the minority of the

Minority get its point on the record.

Mr. ROHRABACHER. A lot of minorities turn out to be right in the

end, right?

Chairman GORDON. It makes us all think, so we thank you for

that, and the gentleman from Louisiana, Mr. Melancon, is recognized for five minutes.

CLIMATE CHANGE IMPACTS: COASTAL LOUISIANA

Mr. MELANCON. Thank you, Mr. Chairman. I appreciate it. I

guess one of the things that I feel needs to be pointed out, it is not

just global warming but it is climate change that is occurring and

it is a combination of factors and I don’t think we are talking extremism. I think we are talking about adaptation and mitigation and

we ought to be making deals to get this thing moving in the right

direction. I have got a grandson so I have got a new vested interest. I have children too and don’t know if I will ever see my greatgrandchildren but I grew up in the south Louisiana marshes, which

Ms. Vansickel is extremely aware of and is cognizant of the importance of it to this entire nation and not just Louisiana. I hope that

whatever we do in the Congress will leave that estuary, that great

area of this country, which most people aren’t aware of, whole and

back to where it should be so that America can benefit from it. So

I am going to concentrate I guess on the coastal areas, the restoration, the rising sea levels and such.

Dr. Burkett, one of your key policy-relevant findings states that

the coastal wetlands ecosystem such as salt marshes are especially

threatened where they are sediment-starved or constrained. Would

this assessment apply to coastal Louisiana?

Dr. BURKETT. Yes. Coastal Louisiana is one of those large mega

deltas that is extremely vulnerable. Do you know that all these deltas around the world now off the coast of Vietnam or the Nile delta

or in Shanghai, these deltas were formed during the past 7,000

years when sea-level rise was relatively miniscule, very small.

They are all very vulnerable to even slight increases in the rate of

sea-level rise, which is very likely to increase during this coming

century so the Louisiana coast is just quite vulnerable. That is why

it is listed as a hot spot of vulnerability. That said though, a lot

of the coast can keep pace with sea-level rise even if it doubles if

you can get the freshwater and the sediment to that marsh so that

it can increase vertically in place. So it is not a hopeless situation.

Mr. MELANCON. And I guess that brings me exactly where I

hoped you would go with it. The influence of human development

and activities along the coast and adjacent watersheds and the

Army Corps of Engineers through the years since 1927 when we

decided we needed to harness or keep within the levies the Mississippi River while facilitating navigation, we have contributed to

the living conditions by accelerating salt compaction along the

coast. So what has man—and I refer to it, when people ask me why

doesn’t the Congress understand what is going on down here, I tell

them that, you know, the Corps is partly at fault but so is the Congress in the United States because all these years we have been

funding wants and concerns of the Mississippi River with the locks

195

and dams and the other structures. Has that manmade situation

along the Mississippi River which there is everything from the Allegheny and the Appalachians all the way to the Rockies and everything in between, Louisiana is the final resting spot for everything, for the good, for the bad, and has that harnessing of that

river and channeling of that river caused the severe problems that

we are experiencing in coastal Louisiana?

Dr. BURKETT. It is the most significant cause of wetland loss in

Louisiana. There are over 300 dams and reservoirs along the Mississippi River drainage that prevent the sediment and freshwater

from getting into the river and then it is being levied all way from

Caro, Illinois, down to Venice, Louisiana, and so the seasonal

overbank flooding that would be required to sustain those wetlands, especially in the light of accelerated sea-level rise, the ability

of that river to maintain that delta, we have a riverless delta basically because of the human influence along the river.

Mr. MELANCON. Yeah, and then there are some people that don’t

believe that there is a hypoxia zone down there, and had we had

been through the years taking the material that we are just summarily putting into the current and let run off the Outer Continental Shelf forming this hypoxia zone, which is of course the nutrients and whatever that is coming from the farmlands all through

the Midwest and northern United States—would it help us at all

if we were able to capture that sediment and with the help of our

government get that sediment back out into the marshes and does

that material in effect become a nutrient for the marshes where

there is hypoxia in the Gulf?

Dr. BURKETT. It would. You have got 120 million tons of sediment just slipping past New Orleans every year out off the edge

of the Outer Continental Shelf due to flood control works basically

not for the benefit of Louisiana as much as up the river. So, you

know, getting that sediment out into the marsh would counteract

these changes that we are talking about, the accelerated sea-level

rise and the increase in storm intensity that will have a dramatic

effect on low-lying coastal wetlands like Louisiana’s.

Mr. MELANCON. One of the things that of course I guess I experience some frustration here is that the relevance of the marshes to

protect our inland cities, for instance, New Orleans. There are

some people that appear to think that New Orleans is expendable

but I go back to when the French took New Orleans and why it

was taken and why America wanted it is because it controlled this

country’s mid-section and all the commerce, and to this day it still

does, and the importance of that city, while it may not be expressed

in national revenue, which I think we could document it does, without these coastal wetlands out there as the buffer, we are the first

that get the problems from the rising elevation of sea level. But I

think is it fair to say that in generations to come all America, particularly the south central part of—the south and center part of the

American states need to be aware that it won’t take long in terms

of my lifetime before we start seeing a real problem for the center

part of this country and along the Gulf Coast in particular?

Dr. BURKETT. Not just because of transportation down the river

but also because of the energy development off the coast there. As

you know, we have got about 3,600 oil and gas platforms off the

196

Louisiana coast. All that product comes onshore. The loop offshore

terminal, you know, that product comes onshore. Two-third of this

country’s imported oil comes through those coastal facilities and

they were all built for shallow—in shallow waters in a low-energy

environment protected by barrier islands but the barrier islands, as

I showed, you know, they are decreasing and so it is going to have

an impact not just in Louisiana. It will affect our country and

internationally.

Chairman GORDON. The gentleman’s time has expired.

Mr. MELANCON. Thank you, sir.

Chairman GORDON. You know, my grandfather used to say the

most important road in the county is the one in front of your house,

and I think what we are starting to see is that this discussion is

moving from the hypothetical to the specific which it is unfortunate

for the country but it is probably better for the continuing discussion.

The gentleman from California, Mr. Bilbray, is recognized and

then Mr. Inglis will be recognized.

AIR INDEXING IN THIRD WORLD COUNTRIES

Mr. BILBRAY. Thank you, Mr. Chairman. I assure the gentleman

from Louisiana, short of basically eliminating the levies on the

west bank, you know, we are just going to have to address the fact

that Algiers is protected from floods and places like Houma and

Bayou D’Arbonne have been protected for 100 years. And that protection actually has created a lot of the problem, and I wouldn’t

want to have to be the representative in that area having to address that issue—and I have been down there at town hall meetings in Billy Tauzin’s old district and try to tell them that yeah,

we are going to be removing the west bank levies because we need

to use that to replenish your shoreline but that may be. A lot of

those areas have been protected from inundation and that inundation is what over the centuries actually built it up and you are in

a real catch-22 and I appreciate that. My wife is from New Orleans

so I spent a lot of time there. My father is from that part of the

world.

Mr. Chairman, can we ask the Committee—I mean the panel, I

come from a background of air resources board from California. I

did the air plan for Mexico City, and one of the things that I really

run into is, how do we do the air indexing in Third World countries? When you talk about the percentage of First World country

emissions and then Third World, you know, so often in my 20

years—18 years of working on clean air stuff, it was like, if it is

not reported, it doesn’t exist. How do we do an index for a Third

World country? How do you determine emissions from countries

that do not have true air indexing systems? Anybody know?

Dr. SCHNEIDER. In terms of local air pollution, I can’t answer

that question. In terms of trying to estimate the global emissions

of greenhouse gases, there certainly are many international institutions which try to collect that data and there is always a debate

at the margin as to whether the official data represents the actual

data. There has been that argument in China about unreported

coal burning, for example. But most of the colleagues I have—I

don’t myself do this work, but I have heard many talks on it. Most

197

of them who do it believe that they think they are accurate 20 percent over time.

Mr. BILBRAY. Satellite photos using how much slash and burn is

going on and estimate how much—how many tons are being emitted per acre or hector?

Dr. SCHNEIDER. There are a variety of techniques that people use

including talking to people locally but you are correct that the data

is not perfect. It is certainly accurate I would guess at the planetary scale to tenths of percent.

Mr. BILBRAY. Let me just tell you——

Chairman GORDON. I would suggest that is one reason we are

trying to get NPOESS up and with those sensors can be helpful in

this regard and it is important that we clean that program up and

get it working if we want to get that good information.

Mr. BILBRAY. The gross deficiency in the estimate of emissions

have all been a bigger problem than anybody is willing to admit

for a long time. The evaporative emissions in California, which has

the best air index in the world, was underestimated by 85 percent.

I want to congratulate whoever is brave enough to stand up and

say corn ethanol is, you know, the equivalent of an environmental

Jimmy Swaggart. The fact of claiming that you are helping the environment by doing what we are doing with corn ethanol, I just

think that we have just got to start saying the emperor has no

clothes on this issue. And in California, we have run into this problem of you don’t do, or say, anything against corn ethanol.

GLOBAL DIMMING

But getting back, is anybody here able to comment on an issue

that is going to be essential for us? Because this panel is going to

have to develop strategies and techniques of how to address this

issue, and if we do not have the proper information going into the

process, what comes out is not going to solve the problem. It may

actually make the problem worse. And I would just like to say, has

anybody here got a handle on this global dimming? Because you

have got to understand, that may totally change our implementation strategy if it is enough of an issue to justify, you know, a scientific review and a policy change. Anybody got a comment on global dimming right now?

Dr. SCHNEIDER. Okay, I will try that again. Since the beginning

of my career, I was weighing the global dimming associated with

hazes around the atmosphere against the warming from greenhouse gases and we made the initial assumption that the hazes,

the dimming was global. In fact, if the dimming were global, it

would be a larger cooling effect than the greenhouse gases. What

we discovered shortly thereafter, and I was proud to publish before

I got attacked, was that only about a sixth of the world was really

experiencing very large increases in these hazes, due to the industrial areas and the biomass burning. I think that the problem you

have is that the direct effects of the dimming, that means between

the clouds when radiation comes in and it is reflected back out to

space and causes a slight cooling, is well understood. What is not

well understood, and this is very clear in IPCC work in Group I,

is that dust particles are the centers upon which droplets in clouds

condense, and clouds are the primary reflectors of solar energy.

198

This is what we call indirect effect. And the indirect effect could

be quite significant and in fact, one of the reasons you see IPCC

tell you 1 degree to 6 degrees C, which is an incredibly large range

of uncertainty in warming to 2090, about half of that is due to the

uncertainty in how the clouds and the reflectivity will change. So

that is real. What we don’t know is exactly in which direction because soot particles are dark and can cause the climate to warm

if they get into clouds and cause them to evaporate. They would enhance warming. If they actually increased the number of drops,

they can enhance cooling. And that is why you will find that most

honest scientific assessments, and most are, talk in ranges and bell

curves because of the issues you raised still remaining not entirely

resolved.

Chairman GORDON. The gentleman’s time expires.

Ms. Giffords is recognized to learn more about the report’s impact on Arizona.

CLIMATE CHANGE IMPACTS: SOUTHERN ARIZONA

Ms. GIFFORDS. Thank you, Mr. Chairman. Let us assume that we

keep doing business as usual. I do represent Southern Arizona. I

am very proud of that area of the country. But two weeks ago,

right before the recess, I was able to co-host Dr. John Overpeck

from the University of Arizona, who is a climatologist and one of

the authors of the first IPCC report. So I am curious if this panel

will address if we continue to do business as usual, we don’t take

any steps, what is going to happen to the West, particularly Southern Arizona, in terms of water resources, in terms of our forests,

also possible changes in terms of immigration with a border country like Mexico, invasive species wildlife and human health?

Dr. PULWARTY. I will take that. One of the major things that we

are seeing in terms of the projections, as I mentioned, is in terms

of decline of water resources within the Colorado basin itself, and

you know very well, 8.23 million acre feet come from the upper

basin into the lower basin. A big aspect of that, especially as it relates to Southern Arizona, of course, is the Central Arizona project

and its right in terms of Colorado River. What we are projecting

is that within—by around 2020, demand will in fact exceed supply

given current trends in terms of drought and given current trends

in terms of temperature and its impact on snow. One of the things

that we should keep in mind regardless of how change is attributed—human, natural or both—is that we have to adapt. There

will be floods, droughts and hurricanes in the future. There is no

denying that. I can’t say very much about the migration issue. It

is not an area that I know anything about. From the standpoint

of Southern Arizona, what we are seeing is increased pressure on

groundwater resources for development purposes and increasing reduction and reliability of Colorado River flow to support that.

There is a slew of other issues that are related to that that we are

beginning to see as a result of dryness. Some of them include dust

storms, as you saw last year. There was a storm blowing into Phoenix. There were quite dramatic pictures of it. And dust is known

to have a negative effect on snow melt as well. So there are combined issues from the standpoint of water resource reliability for

Southern Arizona.

199

Dr. EASTERLING. One general principle that I think we all operate with when asking the question how might climate change affect

any of the systems is that in environments that are already very

dry like Arizona that most of the natural ecosystems are in very

delicate balance with the climate conditions and therefore relatively small changes in climate can result in relatively large

changes in such things as species composition, in other words, the

mix of vegetation types, trees especially in your case, that exist in

the less-managed environments of the State and that would be of

great concern.

Dr. BURKETT. The IPCC has undertaken a special technical report on water, a paper on water that Dr. Pulwarty and I will be

coauthoring. It will come out in about nine months, and if you like,

we can come and present those findings to you. Some of the implications for runoff in the arid Southwest, for example, suggest

through the models—and all this will be captured in the report—

a decline in surface water availability and runoff that will intensity

during the next 50 years.

Dr. PULWARTY. I would want to add something to what Bill is

saying—Dr. Easterling—we have very little understanding of the

increased impact on non-managed systems and you can see it in

terms of the pinion die-off in Southern Arizona and changes in the

forest. What I would like to mention in that context is that the

present drought that we are experiencing in the basin is 1.5 degrees Fahrenheit warmer than the drought in the 1950s, and that

has—that temperature stress has in fact created much larger impacts on the non-managed areas than even during the 1950s. So

my point being is however we attribute change, change is happening and therefore we need to look at adaptation responses.

Ms. GIFFORDS. Mr. Chairman, just a quick follow-up. Some of my

concern is, Arizona is now the fastest growing State in the Nation

so everyone wants to move there. It is a wonderful place this time

of year, but I believe because of this increased growth we have additional concerns in terms of—you know, we just—we are going to

have a lot more emissions, we are going to have a lot more fuel demands. Meanwhile, we have this really delicate ecosystem there

and the situation with the Colorado River water which—and I am

afraid that we just don’t adequately know how to manage all of

this.

Dr. PULWARTY. One of the things that we have to be clear on is

this being able to picture the risks that we are facing in one setting. There are these increasing population demographic pressures

as you are describing but in addition, at the same time we are seeing more collaborative agreements between Nevada and Arizona on

water storage and so on. So we need to look at what some of those

adaptation mechanisms are.

Chairman GORDON. The gentlelady’s time has expired.

Mr. Inglis.

SUNSPOTS

Mr. INGLIS. Thank you, Mr. Chairman. Before I ask about sea

walls, I wonder if somebody can give me an explanation of the sun

theory that Mr. Rohrabacher mentioned and the reaction to that?

200

Chairman GORDON. I think that sunspots are really what is causing this and it is not really global warming. If anybody would like

to address that?

Dr. SCHNEIDER. Well, I can address aspects of it. I have worked

on the problem earlier though not recently, and I could give you

the names of people who work on it directly now, but again, I will

present the summary from what I have heard from the debates

among colleagues. If the energy output of the sun itself in terms

of the total number of watts of energy over every square meter had

changed significantly, and that was responsible for the warming,

then there would be particular fingerprints of that that you would

see in the system. If you increase the energy output of the sun, you

would find the stratosphere, you know, the layer above 10 to 50

miles warming, you would find the middle of the atmosphere

warming, the lower and the surface. If that warming were due to

human effects, greenhouse gases and ozone-depleting substances,

then the fingerprint would be a cooling of the stratosphere because

of the decrease in ozone plus some other, what we call rays enforcing factors, and warming of the lower atmosphere. When climatologists in the Working Group I—and again, you should talk with

them about this more. But when they assign high confidence to the

fact that humans have been implicated at least in the warming of

the last 30 years, it is because that particular fingerprint, cooling

in the stratosphere and warming in the lower atmosphere, is what

occurred. So it is much more consistent with the notion that it was

human effects more than natural. Now, nobody has denied that

natural isn’t part of it, and in fact work I have been personally part

of using plants and animals as surrogate thermometers, Terry

Ruud et all, and she is testifying at another hearing at the moment, what we have found is that when we use models driven only

by natural forces, which include volcanoes and solar effects, that

you predict a small fraction of the observed changes in species, that

is, when birds come back from migration, when plants bloom and

so forth. When we use anthropogenic, you get a better fraction, and

when you use them combined, you get the best fraction. So what

we would argue is that the climate of the most recent half decade

is a mixture of human and anthropogenic factors.

There is one more component of the sun which is more controversial, which is assuming it is not the energy output of the sun that

has created the problem, because this is way too small for that, but

that changes in magnetic fields and particles has affected the

chemistry of the stratosphere and it becomes a trigger to create a

major amplifier for global warming. It is a very complex, and I

would argue somewhat speculative theory. Working Group I scientists have considered it unlikely. There is a very passionate debate in the literature on it, and if you ask me formally, I will be

delighted to send you the somewhat unpleasant articles written by

the various people who are involved. But the one thing I can say

is that those scientists who have claimed that is isn’t the energy

output of the sun, but of these magnetic and particle effects have

never shown how many watts of energy around the planet can be

affected by the hypothesis. Without showing the scale at which the

sun could do it, it is very difficult to compete that against the

human effects because we have very good idea what the scale of

201

human effects are from greenhouse gases, though as I said earlier,

we have much less of an idea about the scale of effects on aerosols.

So I think that the jury is still out on the relative importance of

the sun, but it is very difficult to dismiss the preponderance of evidence which shows the observational record with and without global warming in the model checked against the observational record.

It is very difficult to dismiss that as an accident and require the

sun, and my own personal view, having been doing climate theory

work now for 35 years, is the sun can’t be thrown as irrelevant but

that in the last 30 years it is probably not a very large component

of the major change.

SEA WALLS

Mr. INGLIS. Mr. Chairman, I hope I have time to ask about the

sea walls. It strikes me, you know, obviously there is a huge challenge in places like Indonesia but also places like Hilton Head in

South Carolina, which is near where I grew up. Some high-value

real estate that could be very affected but not many feet or inches,

really, worth of change, and just particularly with the discussion

earlier of the levies, I wonder how realistic it is to combat that or

see an adaptation involving sea walls. Maybe you discussed this

earlier and I wasn’t here but at another hearing but tell me about

sea walls and them as an adaptive strategy.

Dr. BURKETT. Sea walls have the effect of preventing the inland

migration of coastal habitats as sea level rises, and we point that

out in our chapter. Sea walls and also a fortified coast tend to prevent freshwater runoff from getting to the coast and sediments

from getting to the coast, disrupting sediment transport, you know,

back and forth across the coastal zone. With that said, where society deems that protection is the right way to go because of infrastructure or people, whatever that is important to protect, our report suggests that the design of those protective structures would

be more effective in the long run, more cost-effective if they consider the fact that sea-level rise will accelerate this century very

likely, even if emissions were cut off. First, because the change is

already made to the atmosphere, and second, increased intensity of

storms in your area, for example, would warrant a specific design

consideration of these changes that we describe.

Chairman GORDON. The gentleman’s time has expired unless you

would like to explore that further?

Mr. INGLIS. Thank you, Mr. Chairman.

Chairman GORDON. Would the gentleman from Georgia like to

conclude?

THE IPCC PROCESS

Mr. GINGREY. Mr. Chairman, if you will indulge me, I appreciate

that very much and I wanted to ask really all the panelists and

maybe very briefly respond. I know, Dr. Rosenzweig, you have been

involved in all four of the IPCC assessments and I would just like

to know in regard to the process, the changes maybe that have occurred over the period of time, this being the Fourth Assessment.

Is the product that you are producing now, do you all—is there a

consensus agreement that it is going to be very helpful to us in reVerDate 11-MAY-2000 16:07 May 12, 2008 Jkt 032966 PO 00000 Frm 00091 Fmt 6601 Sfmt 6601 C:\WORKD\FULL07\020807\32966A.TXT SCIENCE1 PsN: SCIENCE1
202

gard to the policies that we have to set and certainly we are going

to face that sooner rather than later?

Dr. ROSENZWEIG. I also have worked on all four assessments.

This one as a coordinating lead author, I began four years ago with

an expert workshop, a meeting with experts around the world to

begin to do the assessment of the observed changes now, because

this was the first time we had a chapter for Working Group II on

the changes that are occurring now. The process is measured and

fully reviewed and that is the basis of the science, and it is I think

that strong foundation of the science that goes through expert and

government review provides for a product that we—that does then

stand and provide the document—is the document of record for the

following five years.

Mr. GINGREY. Thank you, Dr. Rosenzweig. Dr. Easterling.

Dr. EASTERLING. Yeah, I would have to add to what Dr.

Rosenzweig has said and to say that since I have also been involved in more than one IPCC assessment, it is very clear that the

governments of the world are taking more and more ownership of

this process, and in a positive way. They are providing the scientists with the key questions that they would like to have addressed and I think we as scientists have felt that we have been

given good guidance and the latitude to be able to, no pun intended, to be able to respond and put our best scientific judgments

out for all to see in a very fair way.

Mr. GINGREY. Dr. Pulwarty.

Dr. PULWARTY. The scale at which the information is produced

to the IPCC meets certain needs, that of the international community. What we are seeing, certainly from the climate change science

program synthesis and assessment reports, is what means to different parts of the U.S. and how we interpret and interact with

people and the types of decisions that they will make. So one caveat that I would make relative to the other comments is the process has worked very well, but there is that extra step that needs

to be taken and we are seeing those within the synthesis and assessment reports that are being produced specifically for the U.S.

Mr. GINGREY. And Dr. Schneider.

Dr. SCHNEIDER. Yes. Thank you. I would share the views of my

colleagues that the process is essential for a variety of reasons and

I recall having been involved in many U.S. National Research

Council studies well before IPCC. When IPCC was first proposed

in 1988, I was asked my opinion about what I thought and I said

oh, my gosh, we spend so much of our time flying around the

world, don’t do this to us again. We won’t reach different conclusions than we have had in the studies in Australia and the U.K.

and so forth. In fact its first general Chairman, Bert Baline, said

the rest of the world hasn’t participated and they don’t entirely

trust the developed countries to give them the straight story. So

IPCC was set up to create credibility across the international community by having the active participation of over 100 governments.

They also dictate the outlines so when you asked us, would this be

of useful utility to policy-makers, the answer is to the extent that

the policy-makers created the outline which dictates what we must

work on, we hope so. But I agree also with Roger Pulwarty that

it won’t be quite as regionally specific as some countries need and

203

that is where their own research councils can add a supplement.

And finally, that government ownership is absolutely critical for

the eventual cooperative strategies that we will have to have

though as the two staff sitting next to you know, sometimes you

have 40-hour sessions to get there and we wish the process occasionally were a little less contentious but it is amazingly comprehensive and the peer review, as Cynthia Rosenzweig pointed

out, is why the reports have such high credibility.

Mr. GINGREY. Thank you very much, Mr. Chairman. Thank you

for your indulgence.

Chairman GORDON. Thank you.

Since the gentleman brought that question up, let me ask, does

anyone on the panel feel like in some cases the summary did not

reflect the full views of the information before because of some, for

lack of a better term, political pressure? No one thinks that occurred? Yes?

Dr. SCHNEIDER. I have never been one to let the perfect crowd

out the good or to say that an 85 percent excellent report should

be given a bad grade because it wasn’t 98 and it is absolutely

amazing how much of the basic underlying science was in the summary for policy-makers, but there were a few casualties that I

think were significant. We had a regional table that would actually

come closer to Mr. Gingrey’s wish being more specific on regional

effects. Whether it disappeared because in the U.N. process where

consensus, meaning any one or two countries effectively, forces the

lowest common denominator was responsible, whether we ran out

of time, it is hard to say. I think the single biggest loss from the

report was a table that was produced which showed the sectors, the

relative increasing damages of function of temperature. It is reflected in Table 19.1 in my testimony but this was a summary

table. Above it in the submission from lead authors was a set of

timelines which showed when in 2020s, 2050s, 2080s one might

achieve two degrees, four or six degrees, because when you look at

the damages and you see them increasingly rapidly as you add degrees of warming but you have no idea whether we are going to be

at one or at three or at five but it shows you the substantial likelihood that we are going to see at least the middle of that range and

could very well at first decimal point odds reach the right-hand

edge, and we were very disappointed that that was removed on the

basis of a few countries’ opposition though we were proud of the

United States for supporting that though were not thrilled when

the United States removed all reference to dangerous anthropogenic interference. I do not know why. But again, anybody who

throws 85 percent of their passes ends up in the Hall of Fame so

overall we are quite satisfied with the report.

Chairman GORDON. This is a recommendation for B students.

Yes, ma’am?

Dr. ROSENZWEIG. I think what is very important for the scientists is that the underlying documents were not changed, so that

anyone who wants to see the entire work of the scientists, can find

it there in terms of the tables, scenarios, and trajectories that Dr.

Schneider just mentioned. The confidence levels of every statement

are in the underlying document, and that they are not changed is

extremely important for the science.

204

Chairman GORDON. Thank you. Well, all good things have to

come to an end. We thank you not only for your testimony today

but more importantly, for the years of hard work you put in. We

look forward to four years from now hearing from you again hopefully with better prognostication. Under the rules of the Committee, the record will be held open for two weeks for Members to

submit additional statements that have any additional questions

they might have for the witnesses. If there are no objections, the

witnesses are dismissed and the hearing is adjourned.

[Whereupon, at 12:23 p.m., the Committee was adjourned.]

(205)

Appendix 1:

ANSWERS TO POST-HEARING QUESTIONS

206

ANSWERS TO POST-HEARING QUESTIONS

Responses by Cynthia Rosenzweig, Senior Research Scientist, NASA Goddard Institute for Space Studies, The Earth Institute at Columbia University

Questions submitted by Representative Ralph M. Hall

Q1. The Summary for Policy-makers states that many projected climate change impacts can be reduced by mitigation. In your area of expertise, specifically which

projected impacts can be reduced by mitigation? Over what time frame would

mitigation reduce those impacts? What are the options for adaptation to those

impacts? How much would it cost to adapt versus mitigate for those impacts?

A1. For agriculture, projected impacts that can be reduced by mitigation include reduction in yields due to high temperature stress, droughts, and floods; reductions

in yields due to changing agricultural pests; and reductions in yields due to saltwater intrusion in coastal areas. Global climate model and crop model simulations

show that mitigation would reduce those impacts in the second half of this century,

roughly from the 2050s on. Adaption options for impacts on agriculture include

shifting planting dates, switching crop varieties and species, breeding for heat,

drought, and flood tolerance, and shifting of agricultural zones to higher latitudes

and away from coasts. In regard to costs, it is difficult to directly costs of mitigation

and adaptation on a sector-by-sector basis. Mitigation is addressed through a set of

larger-scale processes (e.g., reducing emissions of greenhouse gases from energy generation), while adaptation is a process that occurs on more local levels (e.g., at the

scale of a farming region). That being said, projections for agriculture show that at

longer timeframes climate change is likely to cause negative effects on regional and

global agricultural production, beyond which adaptive measures may not be effective. Thus, as stated by the IPCC Working Group II, mitigation and adaptation are

both needed to reduce both short-term and long-term risks of climate change.

Q2. The report states that 20 to 30 percent of plant and animal species are likely

to be at increased risk of extinction if global temperatures exceed 1.5 to 2.5 degrees Celsius above 1990 levels. Over what timeframe would these extinctions

occur? What would be the normal expected extinction rate over that time frame

(i.e., the extinction rate without temperature increase)?

A2. In many but not all scenarios, the temperature levels projected and thus species

extinctions are expected to occur within this century. The uncertainties remain

large, however, since for about two degrees C temperature increase (above pre-industrial levels) the percentage of species extinctions may be as low as 10 percent

or for about three degrees C as high as 40 percent. Depending on the biota, the full

range is between one percent and 80 percent. The IPCC Working Group II assigned

the statement about species extinctions ‘medium confidence,’ which is defined as

‘about five out of 10 assessed chance of being correct.’ The estimates for extinction

that the IPCC provides are based on climate change forcing alone. As for what the

extinction rate would be without climate change, those estimates also vary because

of differences in land-use change predictions. Species extinction estimates for

changes related to habitat destruction from land-use change alone range from one

percent to about 30 percent, depending on the biome (Thomas, 2004). Beyond climate change and land-use change, there will be other driving forces that may compound the stress that ecosystems experience—in same cases affecting the same species but in others threatening new ones.

C.D. Thomas et al. 2004. Extinction risk from climate change. Nature 427:145–

148.

Questions submitted by Representative Dana Rohrabacher

Q1. Did you experience or feel any restrictions or censorship from your agency regarding the work you did on the documents you have produced as a result of

your work related to the IPCC or, in general, climate change?

A1. In regard to my work related to the IPCC, I did not experience restrictions or

censorship from my agency. In regard to my work related to climate change, I have

experienced restrictions from my agency. To give one example, a press release describing my work on climate change effects on agriculture was initially suppressed

and subsequently revised.

Q2. In your testimony, you list three significant limitations/gaps in knowledge in

order to attribute warming to human origin. It seems that these limitations

207

would also apply to limitations in the understanding of warming in general,

human-caused or not. Please explain how these gaps in knowledge apply only

to human-caused climate change. And how can you and/or the IPCC say that

certain findings are ‘highly likely’ given these gaps?

A2. The process of considering the causes of warming takes into account possible

causes and uses global climate models to compare warming from the various causes

of observed warming. The IPCC assigns uncertainties to the radiative forcing factors

and climate scientists include these uncertainties in the global climate model experiments. The simulations show that when human causes are included in the model

simulations there is better agreement with observations, even given the uncertainties, limitations, and gaps in knowledge. Only by adding the human forcing can the

observed warming outside the range of natural variability be satisfactorily explained.

208

ANSWERS TO POST-HEARING QUESTIONS

Responses by Virginia Burkett, Chief Scientist for Global Change Research, U.S. Geological Survey, U.S. Department of the Interior

Questions submitted by Representative Ralph M. Hall

Q1. The Summary for Policy-makers states that many projected climate change impacts can be reduced by mitigation. In your area of expertise, specifically which

projected impacts can be reduced by mitigation? Over what time frame would

mitigation reduce those impacts? What are the options for adaptation to those

impacts? How much would it cost to adapt versus mitigate for those impacts?

A1. The IPCC WGII defines adaptation as an adjustment in natural or human systems in response to actual or expected climatic stimuli or their effects, which moderates harm or exploits beneficial opportunities. The IPCC WGII defines mitigation

as an anthropogenic intervention to reduce the sources or enhance the sinks of

greenhouse gases. All of the key impacts of climate change (see Table 6.1 below) described in the IPCC coastal chapter could be reduced by mitigation. The time required for mitigation to translate into reduced impacts varies among climate drivers

and the biological and physical systems affected. There will be a lag effect of days

to decades for some drivers and systems, and the reduction of effects due to temperature or precipitation changes from reduced emissions of some well-mixed greenhouse gases could lag by decades or longer. In other words, even if GHG concentration could be stabilized at year 2000 levels, global temperature would continue to

rise for several decades. This ‘‘committed warming’’ due to existing GHG levels in

the atmosphere is expected to raise global average temperature another half to one

and one half degrees Fahrenheit. On the other hand, the timing of the reduction

of direct ecosystem impacts caused by changes in carbon dioxide levels (e.g., photosynthesis and respiration) will generally begin to occur immediately following a reduction in greenhouse gas levels in the atmosphere.

Many of the indirect effects of climate change on coasts, however, are ‘‘higherorder’’ impacts that will lag in response to mitigation. Sea level rise is the best example of this latent systems response. Our IPCC coastal chapter authors conclude

that:

Sea-level rise has substantial inertia and will continue beyond 2100 for many

centuries. Irreversible breakdown of the West Antarctica and/or Greenland ice

sheets, if triggered by rising temperature, would make this long-term rise significantly larger, ultimately questioning the viability of many coastal settlements across the globe. The issue is reinforced by the increasing human use of

the coastal zone. Settlement patterns also have substantial inertia, and this

209

issue presents a challenge for long-term coastal spatial planning. Stabilization

of climate could reduce the risks of ice sheet breakdown, and reduce but not

stop sea-level rise due to thermal expansion [Box 6.6]. Hence, it is now more

apparent than the TAR [third assessment report] that the most appropriate response to sea-level rise for coastal areas is a combination of adaptation to deal

with the inevitable rise, and mitigation to limit the long-term rise to a manageable level.

Adaptation options vary among coastal types and geographic regions. Adaptation

options for coping with coastal erosion in the Arctic are quite different from the adaptation options in the Mississippi Delta because of differences in physical, biological and human influences in these two areas and how climate change is affecting

them. In the Mississippi Delta, the delivery of river-borne sediments to the coast

is likely to increase the resilience of coastal habitats to sea level rise while the collapse of thawing permafrost and loss of coastal wetlands in the Arctic could not be

offset to the same degree by adaptations in river management.

One constraint on the successful reduction of climate-related impacts to coastal

systems is the limited ability to characterize in appropriate detail how various

coastal systems, and their constituent parts, will respond to climate change drivers

and to adaptation initiatives. Also, we point out in our chapter that the response

of coastal systems to climate change is not necessarily linear or proportional, and

that there are interactions among coastal systems and other factors (such as human

development on the coast) that make it difficult to predict precisely how changes

in climate (or mitigation) will affect a specific coastal community, marsh, or barrier

island. Another key finding regarding adaptation options is that ‘‘reactive and

stand-alone efforts to reduce climate-related risks to coastal systems are less effective than responses which are part of Integrated Coastal Zone Management (ICZM),

including long-term national and community planning.’’ The chapter concludes that

greater access to wealth and technology generally increases adaptive capacity while

poverty limits adaptation options. A lack of risk awareness or institutional barriers

can also have an important influence on adaptive capacity.

Our chapter closes with an assessment of limits and tradeoffs to adaptation and

implications for sustainable development. The following excerpt summarizes some of

our findings relative to the importance of the combination of adaptation and mitigation for vulnerable coastal regions:

Climate change and sea-level rise increase the challenge of achieving sustainable development in coastal areas, with the most serious impediments in developing countries, in part due to their lower adaptive capacity. It will make

achieving the Millennium Development Goals (UN Secretary General 2006b)

more difficult, especially in terms of Ensuring Environmental Sustainability (reversing loss of environmental resources, and improving lives of slum dwellers,

many of whom are coastal). Adapting effectively to climate change and sea-level

rise will involve substantial investment, with resources diverted from other productive uses. Even with the large investment possible in developed countries,

residual risk remains, as shown by Hurricane Katrina in New Orleans (Box

6.4), requiring a portfolio of responses that addresses human safety across all

events (protection, warnings, evacuation, etc.) and also can address multiple

goals (e.g., the environment) (Evans et al., 2004a; Jonkman et al., 2005). Longterm sea-level rise projections mean that risks will grow for many generations

unless there is a substantial and ongoing investment in adaptation (Box 6.6).

Hence, sustainability for coastal areas appears to depend upon a combination

of adaptation and mitigation (Sections 6.3.2 and 6.6.5).

Regarding the cost to adapt versus mitigate, we draw the following conclusion:

Adaptation costs for vulnerable coasts are much less than the costs of

inaction (high confidence). Adaptation costs for climate change are much

lower than damage costs without adaptation for most developed coasts, even

considering only property losses and human deaths. As post event impacts on

coastal businesses, people, housing, public and private social institutions, natural resources, and the environment generally go unrecognized in disaster cost

accounting, the full benefits of adaptation are even larger. Without adaptation,

the high-end sea level scenarios combined with other climate change (e.g., increased storm intensity) are as likely as not to render some islands and lowlying areas uninhabitable by 2100, so effective adaptation is urgently required.

To illustrate that financial costs are also nonlinear with respect to climate change,

we present the graphic below of estimated flood damages in coastal Argentina. Note

210

the significant threshold in real estate damage costs when flood levels reach two m

(six feet).

Q2. The Summary for Policy-makers states that coasts are projected to be exposed

to increasing risks, including coastal erosion, due to climate change and sealevel rise and the effect will be exacerbated by increasing human-induced pressures on coastal areas. What are the other human-induced pressures on coastal

areas? Even if we decreased greenhouse gas emissions those pressures would still

be there, so how would decreasing emissions help coastal communities with

these problems?

A2. The human-induced pressures on coastal systems are summarized in the following three paragraphs from our chapter:

Few of the world’s coastlines are now beyond the influence of human pressures,

although not all coasts are inhabited (Buddemeier et al., 2002). Utilization of

the coast increased dramatically during the 20th Century, a trend that seems

certain to continue through the 21st Century (Section 6.3.1). Coastal population

growth in many of the world’s deltas, barrier islands, and estuaries has led to

widespread conversion of natural coastal landscapes to agriculture, aquaculture,

silviculture, as well as industrial and residential uses (Valiela, 2006). It has

been estimated that 23 percent of the world’s population lives both within 100

km distance of the coast and <100 m above sea level, and population densities

in coastal regions are about three times higher than the global average (Small

and Nicholls, 2003) (see also Box 6.6). The attractiveness of the coast has resulted in disproportionately rapid expansion of economic activity, settlements,

urban centers, and tourist resorts. Migration of people to coastal regions is common in both developed and developing nations.

Sixty percent of the world’s 39 metropolises with a population of over five million are located within 100 km of the coast, including 12 of the world’s 16 cities

with populations greater than 10 million. Rapid urbanization has many consequences; for example, enlargement of natural coastal inlets and dredging of

waterways for navigation, port facilities, and pipelines exacerbate saltwater intrusion into surface and ground waters. Increasing shoreline retreat and risk

of flooding of coastal cities in Thailand (Durongdej, 2001; Saito, 2001), India

(Mohanti, 2000), Vietnam (Thanh et al., 2004), and the United States (Scavia

et al., 2002) have been attributed to degradation of coastal ecosystems by

human activities, illustrating a widespread trend.

The direct impacts of human activities on the coastal zone have been more significant over the past century than impacts that can be directly attributed to

observed climate change (Lotze et al., 2006; Scavia et al., 2002). The major direct impacts include drainage of coastal wetlands, deforestation and reclamation; and discharge of sewage, fertilizers, and contaminants into coastal waters.

Extractive activities include sand mining and hydrocarbon production; harvests

of fisheries, and other living resources; introductions of invasive species; construction of sea walls and other structures. Engineering structures, such as

damming, channelization, and diversions of coastal waterways, harden the

coast, change circulation patterns and alter freshwater, sediment, and nutrient

delivery. Natural systems are often directly or indirectly altered, even by soft

engineering solutions, such as beach nourishment, and foredune construction

(Hamm and Stive, 2002; Nordstrom, 2000).

Yes, these human-induced pressures that are independent of climate change will

likely be present during the coming decades even if emissions are reduced. These

are also likely to intensify as coastal populations grow in the future, placing addiVerDate 11-MAY-2000 16:07 May 12, 2008 Jkt 032966 PO 00000 Frm 00100 Fmt 6601 Sfmt 6621 C:\WORKD\FULL07\020807\32966A.TXT SCIENCE1 PsN: SCIENCE1
211

tional stress on coastal resources. We conclude that ‘‘[c]urrent pressures are likely

to adversely affect the integrity of coastal ecosystems and thereby their ability to

cope with additional pressures, including climate change and sea-level rise. This is

a particularly significant factor in areas where there is a high level of development,

large coastal populations and high levels of interference with coastal systems.’’ The

reduction of greenhouse gas emissions alone will not eliminate potential impacts, as

noted in the following excerpt from our chapter:

Adaptation (e.g., coastal planning and management) and mitigation (reducing

greenhouse gas emissions) are responses to climate change, which can be considered together (King, 2004) (see this volume Chapter 18). The response of sealevel rise to mitigation of greenhouse gas emissions is slower than for other climate factors (Meehl et al., 2007) and mitigation alone will not stop growth in

potential impacts (Nicholls and Lowe, 2006). However, mitigation decreases the

rate of future rise and the ultimate rise, limiting and slowing the need for adaptation as shown by Hall et al. (2005). Hence Nicholls and Lowe (2006) and Tol

(2006) argued that adaptation and mitigation need to be considered together

when addressing the consequences of climate change for coastal areas. Collectively these interventions can provide a more robust response to human-induced

climate change than consideration of each policy alone.

Adaptation will provide immediate and longer-term reductions in risk in the

specific area that is adapting. On the other hand, mitigation reduces future

risks in the longer-term and at the global scale. Identifying the optimal mix is

problematic as it requires consensus on many issues, including definitions, indicators and the significance of thresholds. Importantly, mitigation removes resources from adaptation, and benefits are not immediate, so investment in adaptation may appear preferable, especially in developing countries (Goklany,

2005).

212

ANSWERS TO POST-HEARING QUESTIONS

Responses by Roger S. Pulwarty, Physical Scientist, Climate Program Office, Office

of Oceanic and Atmospheric Research, National Oceanic and Atmospheric Administration, U.S. Department of Commerce

Questions submitted by Representative Ralph M. Hall

Q1. The Summary for Policy-makers states that many projected climate change impacts can be reduced by mitigation. In your area of expertise, specifically which

projected impacts can be reduced by mitigation? Over what time frame would

mitigation reduce those impacts? What are the options for adaptation to those

impacts? How much would it cost to adapt versus mitigate for those impacts?

A1. The mitigation measure of reducing anthropogenic greenhouse gas emission can

reduce a number of projected climate change impacts. Reducing worldwide greenhouse gas emissions now would eventually act to:

(1) Reduce the future severity of drought in the U.S.,

(2) Reduce the level of ocean acidification affecting coral reefs,

(3) Reduce the severity of coral bleaching events (e.g., a 1–3°C increase in global temperature would result in more bleaching events with small recovery

times, whereas an increase of 2.5–3.0°C could result in widespread mortality), and

(4) Reduce the decline of Arctic sea ice and the rise of sea level.

Because of inertia in the climate system, it would take several decades for any

benefits from mitigation efforts to materialize, hence the need for adaptation in the

short-term. According to the Intergovernmental Panel on Climate Change (IPCC)

modeling and studies, even if complete mitigation were put into place immediately

(meaning even if worldwide anthropogenic carbon dioxide emissions were immediately reduced to zero), because of existing carbon dioxide in the system, models

indicate we are committed to a 0.6°C (1°F) temperature change over the next 50

years.

Many of the unavoidable near-term consequences of global warming can be addressed through adaptation strategies such as building levees and restoring wetlands to protect coasts, altering farm practices to grow crops that can survive higher

temperatures, building infrastructure that can withstand extreme weather, and implementing public health programs to help people in cities survive major heat

waves. Some of these adaptations can provide double dividends in that they may:

(a) enhance resilience and reduce current vulnerabilities to current climate-sensitive

problems including climate variability, as well as (b) help cope with future impacts

of climate changes. As temperatures continue to rise the options for successful adaptation diminish and the associated costs increase. Some near-term adaptation strategies may increase local vulnerability in the longer run. For example in a case

where levees designed to protect the coast also encourage development along the

coast, i.e., in vulnerable regions or when the perceived threat has faded from memory. Another example would be a case where population grows in response to temporarily increased water (due to temperature increases) from glacier-fed rivers that

might ultimately disappear.

The World Bank (2006) estimates that $10 billion–$40 billion per year may be required for that agency to ‘‘climate proof’ its development projects. No similar calculations have been done at the national scale for the United States. It is important

that the costs of mitigation be weighed against the rising costs of adaptation in the

future. Many mitigation efforts can provide additional benefits outside of their target. For example, depending on the approach, implementing the mitigation strategy

of reducing greenhouse gas emissions can lead to reduced air pollution, which benefits both public health and agriculture. Thus many mitigation efforts themselves

may offset some fraction of mitigation costs. The direct costs of mitigation should

also include the potential for longer-term economic benefits of new technology markets being developed in response to climate change.

Adaptation strategies are discussed in the context of droughts and flood below, in

response to Questions 2 and 3.

Q2. The report predicts that drought-affected areas will increase. What parts of the

U.S. are vulnerable to this problem? What amount or percentage increase is predicted? Over what time frame? What could communities do to adapt to increased

drought? If we mitigated greenhouse gas emissions, when would we observe a

reversal of the drought increases?

213

A2. The main areas likely to be affected within the U.S. are the watersheds of the

Colorado River Basin, the Sierra Nevadas, and the Great Lakes. There is a broad

consensus among climate models that the Western U.S. (including the western

Great Plains) will become drier in the 21st century and that the transition to a more

arid climate may already be under way. The inflow into Lake Powell on the Colorado has been significantly below average for all but one year since 1999. Most climate models and scenarios suggest that in the prairies there will be a decrease in

soil moisture (which may decrease average crop yields by 10–30 percent). If these

models are correct, the levels of aridity of the recent multi-year drought or the Dust

Bowl and the 1950s droughts may become the new climatology of the American

Southwest within a time frame of years to decades. It is important to note that the

IPCC to date does not explicitly predict the magnitude and timing of drought consequences because these depend on the amount and rate of warming, and, in some

cases, on society’s ability to adapt. Table 1 shows the most recent trends and projections over North America:

In the case of the Sacramento-Joaquin River and the Colorado River basins in the

Western United States, for example, streamflow changes projected beyond 2020 indicate that it may not be possible to fulfill all of the present-day water demands

(including environmental targets), even with adapted reservoir management (with

flows declining anywhere from 17–25 percent). By 2050 the Sacramento and Colorado River deltas could experience dramatic increases in salinity and subsequent

ecosystem disruption.

The challenges of managing water in the Columbia River basin will likely expand

with climate change due to changes in snowpack and seasonal flows. The ability of

managers to meet operating goals (reliability of supply for particular economic and

environmental needs) will likely drop substantially under climate change. Reliability

losses are projected to reach 25 percent by the end of the 21st century and interact

with operational rule requirements. For example, maintaining current operating

rules would reduce firm power reliability by 10 percent under present climate and

17 percent in years during the warm phase of the Pacific Decadal Oscillation.

Adaptive measures have the potential to moderate the decrease in April snowpack,

but lead to 10–20 percent losses of firm hydropower and lower than current summer

flows (important for fish). The IPCC projects an extended fire season for North

America as well as increased threats from pests and disease (which could significantly enlarge the area burned in a fire). Moreover, because fires release the carbon

stored in trees, an increase in wildfires would accelerate rates of climate change.

The seasonality of key impacts is thus important but is little understood. Integration of climate change adaptation into regional planning processes is in the early

stages of development.

As stated in the answer to Question 1 (above), due to the inertia in the climate

system it will be several decades before any benefits from mitigation efforts materialize, hence the need for adaptation. A mixed portfolio of adaptation and response

214

strategies are needed, with strong emphases on ‘‘learning by doing’’ as society moves

from event to event, and response to response. Some lessons are available from integrated and collaborative programs between federal, states, local and private partners such as the Colorado River and Columbia Basins Adaptive Management Program, and early warning and impacts assessments systems being developed such as

the National Integrated Drought Information System and the Regional Integrated

Sciences and Assessments Programs.

The California Water Plan (2005) identifies two dozen water and land management strategies that can be considered by regional and local entities. These strategies serve to reduce water demand, increase water supply, improve water quality,

practice resource stewardship, improve operational efficiency, and facilitate transfers. In California, urban water-use efficiency and recycled municipal water together

could provide over four million acre-feet annually, while additional groundwater and

surface water storage have the potential for as much as three million acre-feet of

annual supply. Adaptation strategies in drought impacted areas could also reduce

impacts on plants being used for biofuel development and water for hydropower.

With mitigation we would not see a reversal of drought increase for several decades, but we may see less frequent and less dramatic events. Smaller natural

drought events would not be exacerbated by anthropogenic climate change.

Q3. The report predicts that heavy precipitation events will increase and cause increased flood risk. What parts of the U.S. are vulnerable to this climate change

impact? What amount or percentage increase is predicted? Over what time

frame? What could communities do to adapt to increases flood risk? If we mitigated greenhouse gas emissions, when would we observe a reversal of the increased flood risk?

A3. Many coastal and riparian communities and habitats in the U.S. are vulnerable

to increased flood risk due to impacts from climate change. As identified in Table

1 (see Question 1, above) the most recent trends and projections over North America

include projections of increased frequency of heavy precipitation events across most

of the United States, increased annual precipitation across most of North America,

and increased streamflow in most of the eastern United States. Further, sea level

is rising along much of the coast, and the rate of sea level change is projected to

increase in the future. Any increase in sea level could exacerbate the impacts of progressive inundation, storm-surge flooding, and shoreline erosion. In addition to increased flood risk from climate change impacts, coastal communities and habitats

will also be stressed by impacts associated with development and reduced water

quality. Storm impacts are likely to be more severe, especially along the Gulf and

Atlantic coasts. Flood hazards are not limited to the coastal zone. River basins with

a history of major floods (e.g., the Sacramento, the Red River, the upper Mississippi), illustrate the sensitivity of rivers to extreme events and highlight the critical importance of infrastructure design standards, land use planning, and weather/

flood forecasts.

The IPCC projects but does not explicitly predict the magnitude and timing of increased flood risk on coastal and riparian communities because the risk depends on

the amount and rate of warming and, in some cases, on society’s ability to adapt.

In order for communities to adapt to increased flood risk, it is important that they

be aware of early indicators of change in the physical system and also of thresholds

that affect management priorities. Water managers in some countries are already

considering explicitly how to incorporate the potential effects of climate change into

specific designs and multi-stakeholder settings. Integrated water resource and coastal zone management are based around the concepts of flexibility and adaptability,

using measures which can be easily altered or are robust to changing conditions.

For example, in several states adaptive management measures (including water conservation, reclamation, conjunctive use of surface and groundwater and desalination

of brackish water) have been advocated, but not yet fully implemented, as a means

of proactively responding to climate change threats on water supply. Similarly, resilient strategies for flood management and environmental restoration, such as allowing rivers to temporarily flood and reducing exposure to flood damage, might be

preferable to (or combined with) traditional ‘‘resistance’’ (protection) strategies.

As stated in answer to Question 1 (above), because of inertia in the climate system, it would take several decades for any benefits from mitigation efforts to materialize, hence the need for adaptation in the short-term. According to IPCC modeling

and studies, even if complete mitigation were put into place immediately (meaning

if anthropogenic carbon dioxide emissions were immediately reduced to zero), because of existing carbon dioxide in the system, models suggest we are committed

to a 0.6°C (1°F) temperature change over the next 50 years, and any associated impacts created by this temperature change.

215

Questions submitted by Representative Dana Rohrabacher

Q1. Did you experience or feel any restrictions or censorship from your agency regarding the work you did on the documents you have produced as a result of

your work related to the IPCC or, in general, climate change?

A1. No. I did not experience or feel any restrictions or censorship from my agency

in the context of IPCC-related work.

Q2. In your testimony, you note that unmitigated Climate change could in the longterm exceed the capacity of the different natural, managed and human systems

to adapt. Please give us your opinion about that minimum point, say measured

in temperature increase or greenhouse gas concentration that this might happen?

A2. The IPCC concluded there is high confidence that the ability of ecosystems to

adapt naturally to climate change is likely to be exceeded over the next century. Irreversible or abrupt impacts from the interactions between climate and other

changes and drivers can lead to decline of about 20–30 percent of species assessed

so far for average warming exceeding 1.5–2.5°C and significant (with high confidence) of greater than 40 percent assessed at 4°C. A description of projected impacts that we might expect to see with increasing thresholds of temperature change

includes:

a. 1–2°C—Increased risk of extinction 20–30 percent of species assessed so far,

most corals bleached (with attendant economic impacts)

b. 2–3°C—Major changes in natural systems, including widespread coral mortality

c. 3–4°C—About 30 percent of coastal wetlands lost (reducing storm buffers and

productivity)

d. 5°C—Extinction of more than 40 percent species assessed

Other as yet little understood impacts relate to outbreaks of pests such as the

bark beetle affecting forest conditions and wildfire risks. The thresholds in such

cases are related to night-time temperature increases, such as is the temperature

increases occurring the West, which increases the viability of the organisms concerned.

Q3. In your testimony you list five efforts in developing research and management

partnerships. In your opinion, what timeline would be needed to develop these

efforts in order for them to have a significant effect on adaptation planning?

A3. In order to have a significant effect on adaptive planning, developing research

and management partnerships require:

• Enhancement of networks of systematic observations of key elements of physical, biological, managed and human systems affected by climate change, particularly in regions where such networks have been identified as insufficient;

• Research into understanding and managing physical, biological and human

systems where there is a risk of irreversible change due to climate and other

stresses;

• Increased understanding of the potential costs and benefits of impacts due to

various amounts of climate change, of damages avoided by different levels of

emissions reduction, and of options for adapting to these impacts and managing the risks;

• Studies to explore how adapting to climate change and the pursuit of sustainable development can be complementary; and

• ‘‘Learning by doing’’ approaches, where the base of knowledge is enhanced

through accumulation of practical experience.

Each of these elements is already being undertaken to some extent, but each is

disparate, limiting the comparison of lessons learned and the diffusion of innovations. In the case of a limited systematic network of observations, it becomes difficult to ascertain the baseline against which projected changes are to be judged and

thus the economic benefits of having such information. In this situation is increasingly important to adapt through changes proactively and as events occur. A mixed

portfolio of strategies is needed, with strong emphases on ‘‘learning by doing’’ across

sectors as society moves from event to event and response to response.

Some lessons are available from integrated programs between federal, states, local

and private partners such as the Colorado and Columbia River Basins Adaptive

Management Programs, and early warning and impacts assessments systems being

developed such as the National Integrated Drought Information System and the ReVerDate 11-MAY-2000 16:07 May 12, 2008 Jkt 032966 PO 00000 Frm 00105 Fmt 6601 Sfmt 6621 C:\WORKD\FULL07\020807\32966A.TXT SCIENCE1 PsN: SCIENCE1
216

gional integrated Sciences and Assessments Programs. The time scales for implementation of such collaborative programs are two years for developing or building

on existing but not yet coordinated networks at the local, State and regional or watershed levels, and 5–10 years to reach effective implementation. We are likely to

experience the benefits of adaptation more immediately than the benefits of mitigation, and adaptation would also reduce societal vulnerability in some areas to climate variability as well as changes. Given the rates and magnitudes of climate

changes (and, in many cases, the as yet uncertain relationships between anthropogenic temperature changes and climate variability including El Nin ̃ o, decadal-scale

changes in hurricane numbers, multi-year drought duration and magnitude) mitigation by itself will not prevent climatic risks.

References

California Department of Water Resources. (2005) California Water Plan Update

2005. Volume 1, Chapter 4: Preparing for an Uncertain Future. Available at http:/

/www.waterplan.water.ca.gov/climate/index.cfm

Intergovernmental Panel on Climate Change (2007) Chapter 3, Freshwater Resources and their Management (68 pp.), and Chapter 17, Assessment of Adaptation

Practices, Options, Constraints and Capacity (49 pp.) In: Climate Change 2007: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Fourth

Assessment Report of the Intergovernmental Panel on Climate Change [M. Parry and

O. Canziani, eds.]. Cambridge University Press, Cambridge, United Kingdom and

New York, NY, USA. (Full report not yet released.)

Seager, R., M. Ting, I. Held, Y. Kushnir, J. Lu, G. Vecchi, H.P. Huang, N. Harnik,

A. Leetmaa, N.C. Lau, C. Li, J. Velez, and N. Naik. (2007) Model Projections of an

Imminent Transition to a More Arid Climate in Southwestern North America.

Science. 316(5828): 1181–1184.

World Bank (2006) Clean Energy and Development: Towards an Investment Framework, Annex K. World Bank, Washington, D.C. 157 pp.

217

ANSWERS TO POST-HEARING QUESTIONS

Responses by Stephen H. Schneider, Melvin and Joan Lane Professor for Interdisciplinary Environmental Studies; Professor, Department of Biological

Sciences; Senior Fellow, Center for Environmental Science and Policy at the

Woods Institute for the Environment, Stanford University

Questions submitted by Representative Ralph M. Hall

Q1. The Summary for Policy-makers states that many projected climate change impacts can be reduced by mitigation. In your area of expertise, specifically which

projected impacts can be reduced by mitigation? Over what time frame would

mitigation reduce those impacts? What are the options for adaptation to those

impacts? How much would it cost to adapt versus mitigate for those impacts?

A1. Mitigation. How mitigation would lower the impacts of projected climate

changes depends on the amount of mitigation relative to a projection of unmitigated

greenhouse gas increases-the so called ‘‘baseline’’—as well as which impact is being

considered. Recall in my written testimony I pointed out that IPCC showed that the

number of ‘‘key vulnerabilities’’ and their intensities increase substantially with

warming levels. In that prepared testimony I included the summary Table 19.1 from

the IPCC Working Group II Fourth Assessment Report, which maps levels of warming with projected impacts. To give a few examples, the loss of species is estimated

to be greater than 40 percent of known plants and animals for warming above four

degrees Celsius, but would be less than 20 percent for warming less than 1.5°C

above 1990 levels. Similarly, commitment to near total deglaciation of Greenland Ice

Sheet—with more than five meters of sea level rise over centuries to millennia—

is projected as likely for warming of 4°C or more, but for warming under 1.5°C some

melting is inevitable, but much less and thus much less sea level rise. Similar statements could be made about hurricane intensity, wildfire incidence, etc.

The projected ‘‘likely’’ range of future warming to the end of this century from

Working Group I was in the range of 1.1 to 6.4°C above 1990 levels. About half this

uncertainty is due to insufficient understanding of the climate sensitivity—a property of the climate system. The other half of the uncertainty range is at our control:

via emissions decisions. If we chose as a matter of policy to invest in less polluting

technologies (e.g., the A1T scenario from IPCC), then we could have a much greater

chance of staying below 2°C additional warming, whereas if we persist on a more

business as usual pathway with fossil fuel intensive emission (e.g., the A1FI scenario from IPCC), then it is much more likely to exceed that level of warming and

trigger a much large number—and degree of intensity—of key vulnerabilities.

Working Group III summarizes costs of mitigation, concluding, again in very

broad terms, that typically proposed mitigation activities cost somewhere from a few

tenths of a percent gain in the GDP up to several percent loss over the time frame

of a half century. The WGIII authors also note that this is a small fraction of the

usually projected growth rate of the world economy—typically estimated to be at

least two percent per year. Thus, if the economy in 2050 were to be two percent

lower than baseline levels due to mitigation policies that reduced CO2 levels by, say,

100 parts per million, even that level of costs would be made up in one year of normal economic growth.

Adaptation. As to costs of adaptation, that is the subject of Chapter 20 of Working

Group II, and again it is very difficult to generalize other than to say that for less

warming, adaptive measures are much less costly than for more warming—when in

fact adaptation may not even be feasible. Indeed, in Table 19.1 you will note that

for many entries we categorize them as ‘‘key’’ impacts or vulnerabilities precisely because above certain temperature levels adaptive capacity is markedly reduced. It is

difficult to generalize across the many sectors of impacts and the economic status

of groups—which itself markedly affects adaptive capacity. However, some broad

generalizations include that human systems—such as agriculture—especially in

cooler places with well developed economies—have much higher adaptive capacity

than similar systems in hotter and poorer countries and that natural ecosystems

typically have the least adaptive capacity.

Finally, I do not see adaptation and mitigation as trade-offs, but rather as complements, since some degree of climate change is likely—at least two degrees C

warming above pre-industrial levels is a better than even bet in my view—and thus

some adaptation is essential to reduce impacts. But since the literature suggests

that adaptive capacity goes down quickly with warming above a few degrees, this

implies the need for mitigation over time to prevent reaching such levels of climate

218

change, though whether to label any level as ‘‘dangerous’’ involves both scientific assessments and value judgments.

Questions submitted by Representative Dana Rohrabacher

Q1. In your testimony you quote Article Two of the UN Framework Convention on

Climate Change which. discusses the stabilization level of greenhouse gas concentrations that would prevent dangerous anthropogenic interference with the

climate system. What is your opinion on what that level might be?

A1. What is judged as ‘‘dangerous’’ climate change is a combination of scientific

input on risks (what can happen, what are the odds and to whom would the risks

fall) as a function of levels of warming and value judgments on how much risk is

‘‘too much’’—and thus could be interpreted as ‘‘dangerous.’’ Since I have been asked

for my personal opinion on this, it will be a mixed judgment: my reading of the scientific literature on the risks and my personal philosophy, which in brief is not to

take significant chances with the planetary life support systems.

To be more specific, I believe it is already too late to prevent some dangerous outcomes—in fact increased wildfires in the U.S. West, heat waves in Europe and drying in Mediterranean climates—which includes California—has already co-occurred

with the rapid warming trend of the past 40 years. We are committed to at least

another degree Celsius warming, and it will take major mitigation actions to stay

even at that level rather than much higher. Thus, I believe increased hurricane intensities, melting glaciers, drying arid zones, increased wildfire incidence and commitments to some species extinctions and sea level rises are already inevitable.

However, the number and intensity of such key vulnerabilities is dramatically reduced if we can keep the additional warming to no more than another degree or

so Celsius, and it would be dramatically more dangerous if the warming is allowed

to exceed an additional 2°C. Thus, for me, stabilizing the long-term levels of carbon

dioxide equivalent concentrations in the atmosphere at 450 parts per million or less

would trigger relative few additional dangerous events rather than allowing it to

proceed as is now in motion toward 600 ppm or more, with many more dangerous

risks.

The quickest way to summarize this complex issue based on a group consensus

rather than my personal opinion, is to quote from the executive summary of the

IPCC AR4 Chapter 19, Working Group II Report, of which I was a Coordinating

Lead Author:

‘‘General conclusions include [19.3]:

• Some observed key impacts have been at least partly attributed to anthropogenic climate change. Among these are increases in human mortality, loss of

glaciers, and increases in the frequency and/or intensity of extreme events.

• Global mean temperature changes of up to 2°C above 1990–2000 levels would

exacerbate current key impacts, such as those listed above (**), and trigger

others, such as reduced food security in many low-latitude nations (*). At the

same time, some systems such as global agricultural productivity, could benefit (o/*).

• Global mean temperature changes of 2° to 4°C above 1990–2000 levels would

result in an increasing number of key impacts at all scales (**), such as widespread loss of biodiversity, decreasing global agricultural productivity and

commitment to widespread deglaciation of Greenland (**) and West Antarctic

(*) ice sheets.

• Global mean temperature changes greater than 4°C above 1990–2000 levels

would lead to major increases in vulnerability (***), exceeding the adaptive

capacity of many systems (***).

• Regions that are already at high risk from observed climate variability and

climate change are more likely to be adversely affected in the near future due

to projected changes in climate and increases in the magnitude and/or frequency of already-damaging extreme events.’’

Key to symbols: o,*,**,*** imply low, medium, high and very high confidence, respectively, in the conclusions as assessed by the Chapter 19 author team.

Q2. In your testimony you show a table which points out that at about a two to three

degree centigrade temperature rise, there is a 50/50 chance that the ocean level

will rise two to seven meters. But the WGI report suggests a rise of less than

half a meter worst case. Why didn’t you use this IPCC-accepted number in the

table? Was the larger number vetted through the normal IPCC process?

219

A2. The WGII statement on which the testimony is based refers to long-term sea

level rise, i.e., beyond the 21st century. The WGI table noted in your question refers

to the 21st century sea level rise only. The risk of a two to seven meter sea level

rise arises from the possibility of partial or total deglaciation of the Greenland ice

sheet over the long-term, as indicated in Table 19.1 of Chapter 19, IPCC WGII.

This table is based on WGI Summary for Policy-makers and Chapters 6 and 10,

and WGII section 19.3.5.3. The Summary for Policy-makers of the WGI report

states:

‘‘Contraction of the Greenland ice sheet is projected to continue to contribute

to sea level rise after 2100. Current models suggest ice mass losses increase

with temperature more rapidly than gains due to precipitation and that the surface mass balance becomes negative at a global average warming (relative to

pre-industrial values) in excess of 1.9 to 4.6°C. If a negative surface mass balance were sustained for millennia, that would lead to virtually complete elimination of the Greenland ice sheet and a resulting contribution to sea level rise

of about 7 m. The corresponding future temperatures in Greenland are comparable to those inferred for the last interglacial period 125,000 years ago, when

paleoclimatic information suggests reductions of polar land ice extent and 4–6

m of sea level rise.’’ [6.4, 10.7]

In WGI Chapter 6, it is noted that Greenland contributed at least 2 m to sea level

rise during the warm period 125,000 years ago, when polar temperatures were 3 to

5°C warmer than today. By combining information from models and paleoclimate

data in the WGI report, WGII determined that warming of 1–4°C versus present entailed a risk of 2–7 m sea level rise over the long-term. That is the judgment reflected in Table 19.1.

Given the uncertainties in ice sheet modeling and paleoclimate data, WGII assessed confidence in this risk at ‘‘medium,’’ i.e., about a 50–50 chance of being correct according to IPCC usage. WGI did not specifically assess the risk. WGII, as required by its Plenary Agreed Outline, took a risk-management approach and thus

made a scientific judgment on the confidence that could be assigned to all major

statements. Since risk is probability times consequences, and since risk-management requires estimates of likelihood, WGII thus met its obligations in that regard

by considering confidence levels in the face of available scientific knowledge.

In plenary session in Brussels in April 2007, governments approved the following

language that embodies the information in Table 19.1 of WGII:

‘‘Very large sea-level rises that would result from widespread deglaciation of

Greenland and West Antarctic ice sheets imply major changes in coastlines and

ecosystems, and inundation of low-lying areas, with greatest effects in river deltas. Relocating populations, economic activity, and infrastructure would be costly and challenging. There is medium confidence that at least partial

deglaciation of the Greenland ice sheet, and possibly the West Antarctic ice

sheet, would occur over a period of time ranging from centuries to millennia for

a global average temperature increase of 1–4°C (relative to 1990–2000), causing

a contribution to sea level rise of 4–6 m or more. The complete melting of the

Greenland ice sheet and the West Antarctic ice sheet would lead to a contribution to sea-level rise of up to 7 m and about 5 m, respectively.’’ [Working Group

I Fourth Assessment 6.4, 10.7; Working Group II Fourth Assessment 19.3]

This text was approved by all governments after a debate in which the points

raised above in response to your question were aired at the Plenary sessions.

(221)

Appendix 2:

ADDITIONAL MATERIAL FOR THE RECORD

222

More Trees, Less Global Warming, Right?—Not Exactly

Scientific American

APRIL 10, 2007

A 150-year simulation of worldwide deforestation finds that tropical forests are

carbon sinks and boreal forests contribute to warming.

Before compact fluorescent light bulbs and ethanol, the first line of defense

against global warming was planting trees.

Forests, after all, cool the atmosphere by drinking in carbon dioxide from the air.

A new study, however, published in Proceedings of the National Academy of Sciences

reports that forests’ other climatic effects can cancel out their carbon cleaning advantage in some parts of the world. Using a three-dimensional climate model, the

research team mimicked full global deforestation and also studied the effects of

clear-cutting in different regions of latitude, such as the tropics and boreal zones.

Apparently, these natural carbon sinks only do their job effectively in tropical regions; in other areas, they have either no impact or actually contribute to warming

the planet. In fact, according to this model, by the year 2100, if all the forests were

cut and left to rot, the annual global mean temperature would decrease by more

than 0.5 degrees Fahrenheit.

‘‘I’m not sure the slight amount of cooling is necessarily significant, but that removing all the forest produced little change’’ on temperature is, says study co-author

Ken Caldeira, an ecologist at the Carnegie Institution of Washington’s Department

of Global Ecology in Stanford, Calif. ‘‘I think what’s interesting is this global cancellation was a product of very different responses at different latitudes.’’

Trees perform three major climate functions: They absorb carbon, which they pull

from the atmosphere, creating a cooling effect; their dark green leaves absorb light

from the sun, heating Earth’s surface; and they draw water from the soil, which

evaporates into the atmosphere, creating low clouds that reflect the sun’s hot rays

(a mechanism known as evotranspiration that also leads to cooling). These three factors—the second two being largely ignored in climate models up to this point, according to Caldeira—taken together created very different results in the primary

latitudes studied: the equatorial tropic zone; the mid-latitudes that include most of

the U.S.; and the boreal areas, which are subarctic and include much of Canada,

Russia and the northern extremities of the U.S.

In all three regions, forests dutifully perform their task of sucking carbon dioxide

from the air, but light absorption and evotranspiration vary wildly. In tropical

zones, forests have a significant, overall cooling effect. The soil is very wet and, so,

via evotranspiration, the trees are covered by low-lying clouds that create a small

albedo (power of light that is reflected by a surface). In non-tropical areas, Caldeira

explains, ‘‘the real significant factor is whether there’s snow on the ground in the

winter.’’ If a forest covers a snowy expanse, ‘‘that has a strong warming influence,’’

he notes, because of little cloud cover resulting from less efficiency in evaporating

water. The poor cloud formation coupled with the intense absorption of light by the

trees ‘‘far overwhelms the cooling influence of the carbon storage,’’ he says.

‘‘In mid-latitudes, we got that it was basically a wash—the carbon dioxide effects

were pretty much directly balanced by the physical effects,’’ Caldeira says. He attributes this to the low contrast between light absorption from trees and from grass

in pastures, though he notes that because there are some areas with wintry snow

cover, the loss of a forest will probably have a slight, if any, cooling effect. He uses

this example to point out the relative influence of the different forest functions.

Whereas carbon levels can affect warming on a global scale, the effects of increased

albedo and poor evotranspiration would affect temperatures only on a regional level.

For instance, he says, ‘‘if you remove all the forest in the U.S., it would probably

heat up the world, but have a slight cooling influence on the U.S., itself.’’

Navin Ramankutty, an Assistant Professor of Geography and Earth system

sciences at McGill University in Montreal, says this study is the first to take a comprehensive look at the consequences of deforestation on the entire world. ‘‘You can’t

just blindly go ahead and reforest and that will tackle climate change,’’ he says,

pointing out a key finding in the study. ‘‘If you think about conservation groups,

they’re all talking about planting trees. We should be protecting tress for other reasons.’’

Caldeira agrees, saying that protecting the forest should be part of an effort to

sustain the world’s biodiversity. He also adds that the findings do not endorse clearcutting or destroying wildlife habitats. ‘‘I think that it’s important to look at preventing climate change as a means rather than an end in itself,’’ he says. ‘‘Too narrow a focus on global warming and a loss of the broader focus of protecting life on

223

this planet can lead to perverse outcomes.’’ Rather than looking to forests to solve

the current climate crisis by capturing carbon dioxide, he suggests targeting our

‘‘energy system,’’ which continues to create the pollutant.

224

Why So Gloomy?

GUEST OPINION

BY RICHARD S. LINDZEN

SPECIAL TO Newsweek

April 16, 2007 issue—Judging from the media in recent months, the debate over

global warming is now over. There has been a net warming of the earth over the

last century and a half, and our greenhouse gas emissions are contributing at some

level. Both of these statements are almost certainly true. What of it? Recently many

people have said that the Earth is facing a crisis requiring urgent action. This statement has nothing to do with science. There is no compelling evidence that the

warming trend we’ve seen will amount to anything close to catastrophe. What most

commentators—and many scientists—seem to miss is that the only thing we can say

with certainly about climate is that it changes. The Earth is always warming or

cooling by as much as a few tenths of a degree a year; periods of constant average

temperatures are rare. Looking back on the Earth’s climate history, it’s apparent

that there’s no such thing as an optimal temperature—a climate at which everything is just right. The current alarm rests on the false assumption not only that

we live in a perfect world, temperature-wise, but also that our warming forecasts

for the year 2040 are somehow more reliable than the weatherman’s forecast for

next week.

A warmer climate could prove to be more beneficial than the one we have now.

Much of the alarm over climate change is based on ignorance of what is normal for

weather and climate. There is no evidence, for instance, that extreme weather

events are increasing in any systematic way, according to scientists at the U.S. National Hurricane Center, the World Meteorological Organization and the Intergovernmental Panel on Climate Change (which released the second part of this year’s

report earlier this month). Indeed, meteorological theory holds that, outside the

tropics, weather in a warming world should be less variable, which might be a good

thing.

In many other respects, the ill effects of warming are overblown. Sea levels, for

example, have been increasing since the end of the last ice age. When you look at

recent centuries in perspective, ignoring short-term fluctuations, the rate of sealevel rise has been relatively uniform (less than a couple of millimeters a year).

There’s even some evidence that the rate was higher in the first half of the twentieth century than in the second half. Overall, the risk of sea-level rise from global

warming is less at almost any given location than that from other causes, such as

tectonic motions of the Earth’s surface.

Many of the most alarming studies rely on long-range predictions using inherently

untrustworthy climate models, similar to those that cannot accurately forecast the

weather a week from now. Interpretations of these studies rarely consider that the

impact of carbon on temperature goes down—not up—the more carbon accumulates

in the atmosphere. Even if emissions were the sole cause of the recent temperature

rise—a dubious proposition—future increases wouldn’t be as steep as the climb in

emissions.

Indeed, one overlooked mystery is why temperatures are not already higher. Various models predict that a doubling of CO2 in the atmosphere will raise the world’s

average temperature by as little as 1.5 degrees Celsius or as much as 4.5 degrees.

The important thing about doubled CO2 (or any other greenhouse gas) is its ‘‘forcing’’—its contribution to warming. At present, the greenhouse forcing is already

about three-quarters of what one would get from a doubling of CO2. But average

temperatures rose only about 0.6 degrees since the beginning of the industrial era,

and the change hasn’t been uniform—warming has largely occurred during the periods from 1919 to 1940 and from 1976 to 1998, with cooling in between. Researchers

have been unable to explain this discrepancy.

Modelers claim to have simulated the warming and cooling that occurred before

1976 by choosing among various guesses as to what effect poorly observed volcanoes

and unmeasured output from the sun have had. These factors, they claim, don’t explain the warming of about 0.4 degrees C between 1976 and 1998. Climate modelers

assume the cause must be greenhouse gas emissions because they have no other explanation. This is a poor substitute for evidence, and simulation hardly constitutes

explanation. Ten years ago climate modelers also couldn’t account for the warming

that occurred from about 1050 to 1300. They tried to expunge the medieval warm

period from the observational record—an effort that is now generally discredited.

The models have also severely underestimated short-term variability El Nin ̃ o and

the Intraseasonal Oscillation. Such phenomena illustrate the ability of the complex

225

and turbulent climate system to vary significantly with no external cause whatever,

and to do so over many years, even centuries.

Is there any point in pretending that CO2 increases will be catastrophic? Or could

they be modest and on balance beneficial? India has warmed during the second half

of the 20th century, and agricultural output has increased greatly. Infectious diseases like malaria are a matter not so much of temperature as poverty and public

health policies (like eliminating DDT). Exposure to cold is generally found to be both

more dangerous and less comfortable.

Moreover, actions taken thus far to reduce emissions have already had negative

consequences without improving our ability to adapt to climate change. An emphasis

on ethanol, for instance, has led to angry protests against corn price increases in

Mexico, and forest clearing and habitat destruction in Southeast Asia. Carbon caps

are likely to lead to increased prices, as well as corruption associated with permit

trading. (Enron was a leading lobbyist for Kyoto because it had hoped to capitalize

on emissions trading.) The alleged solutions have more potential for catastrophe

than the putative problem. The conclusion of the late climate scientist Roger

Revelle—Al Gore’s supposed mentor—is worth pondering: the evidence for global

warming thus far doesn’t warrant any action unless it is justifiable on grounds that

have nothing to do with climate.

Lindzen is the Alfred P. Sloan Professor of Meteorology at the Massachusetts Institute of Technology. His research has always been funded exclusively by the U.S. Government. He receives no funding from any energy companies.

 2007 Newsweek, Inc.

226

(227)

THE STATE OF CLIMATE CHANGE SCIENCE

2007: THE FINDINGS OF THE FOURTH ASSESSMENT REPORT BY THE INTERGOVERNMENTAL PANEL ON CLIMATE CHANGE

(IPCC), WORKING GROUP III: MITIGATION

OF CLIMATE CHANGE

WEDNESDAY, MAY 16, 2007

HOUSE OF REPRESENTATIVES,

COMMITTEE ON SCIENCE AND TECHNOLOGY,

Washington, DC.

The Committee met, pursuant to call, at 10:05 a.m., in Room

2318 of the Rayburn House Office Building, Hon. Bart Gordon

[Chairman of the Committee] presiding.

228

229

HEARING CHARTER

COMMITTEE ON SCIENCE AND TECHNOLOGY

U.S. HOUSE OF REPRESENTATIVES

The State of Climate Change Science 2007:

The Findings of the Fourth Assessment

Report by the Intergovernmental Panel on

Climate Change (IPCC), Working Group III:

Mitigation of Climate Change

WEDNESDAY, MAY 16, 2007

10:00 A.M.–12:00 P.M. 2318 RAYBURN HOUSE OFFICE BUILDING

Purpose

On May 16, 2007, the Committee on Science and Technology will hold a hearing

on the third section of the 2007 Fourth Assessment Report, Climate Change 2007:

Mitigation of Climate Change, prepared by Working Group III of the Intergovernmental Panel on Climate Change (IPCC). Released in Bangkok, Thailand, on May

4, 2007, the summary document highlights the key findings of the comprehensive

appraisal of the current state of scientific knowledge on strategies to mitigate climate change. The full underlying report will be released later this year.

The Committee will hear testimony from three witnesses who will discuss the

findings of the Report and current mitigation technologies and strategies.

Key Findings of the 2007 Working Group III Report

On May 4, 2007 the Intergovernmental Panel on Climate Change (IPCC) released

the third section of its Fourth Assessment Report, entitled ‘‘Mitigation of Climate

Change.’’ This third section of the IPCC Fourth Assessment Report builds upon information contained in the previous reports. Working Group III analyzed mitigation

options for the main economic sectors in the near-term and provided information on

long-term mitigation strategies for various stabilization levels, paying special attention to implications of different short-term strategies for achieving long-term goals.

Furthermore, the report addresses the relationship between mitigation and sustainable development. The Working Group was co-chaired by Dr. Ogunlade Davidson

from Sierra Leone and Dr. Bert Metz from The Netherlands.

Held from April 30th through May 3rd, the 9th plenary session of Working Group

III (WGIII) gathered government delegates from more than one hundred countries,

together with the WGIII Lead Authors. The IPCC-produced documents, including

this Summary for Policy-Makers (SPM), are consensus documents, meaning that all

member governments approve the Summary documents and the underlying chapters

before each document is released.

This report updates information from the Third Assessment Report based on research conducted over the past six years. Looking in detail at the most promising

technologies for reining in heat-trapping gases, Working Group III’s report outlines

the need for improving energy efficiency in buildings, vehicles and appliances; shifting energy sources away from fossil fuels, retaining forests as a carbon sinks, and

reducing emissions associated with agriculture.

Greenhouse Gas Emission Trends

Global greenhouse gas (GHG) emissions have grown since pre-industrial times

and continue to grow. They increased by 70 percent between 1970 and 2004, and

by 24 percent between 1990 and 2004. Growth in CO2 emissions dominates the

growth in greenhouse gases. The growth in emissions has come from all sectors with

the greatest percentage increases coming from the energy supply, transport, and industry sectors.

Emissions associated with income and population growth have overwhelmed decreases in the amount of energy utilized per unit growth (energy intensity) and continue to drive growth in emissions. Under current climate change mitigation policies

global GHGs will continue to grow over the next few decades. Current policies

230

adopted have limited greenhouse gas emissions, but the scale of adoption is too

small to counteract factors driving growth in emissions. Under scenarios assuming

no new mitigation strategies are adopted, emissions will increase by 25–90 percent

by 2030. Two thirds of these increases will come from the less developed countries.

Mitigation in the Short-Term (2007–2030)

Released earlier this year, the first two sections of the 2007 Fourth Assessment

Report present a comprehensive appraisal of the current state of scientific knowledge of climate change and the impacts of that change on natural and human systems around the world.

The first two Working Groups presented information about the potential impacts

associated with continued patterns of GHG emissions, making a strong case for

mitigation. The report prepared by Working Group III focuses on options for mitigating climate change through a variety of technologies and policies. Some greenhouse-gas emissions can be cut through straightforward, cost-neutral measures such

as improving insulation and replacing incandescent light bulbs with fluorescent

lighting. Other techniques, such a Carbon Capture Storage (CCS), require substantial upfront funding, additional research, and a re-orientation of industry practices.

Figure 1 illustrates the technologies and practices that Working Group III identifies

as currently commercially available.

231

1Pages 26 and 27 of the Summary for Policy-makers.

Working Group II reported that global average temperature increases above two

to four degrees Centigrade would lead to severe impacts in many parts of the world

that could not be overcome by adaptation strategies. In order to avoid temperature

increases in this range, atmospheric concentrations of carbon dioxide (CO2) need to

be stabilized in a range of 445–490 ppm.

Working Group III asserts it will be easier to reach and maintain a lower target

stabilization range if mitigation efforts are undertaken early. This is because infrastructure built today has an associated energy demand that will go forward for the

life of the infrastructure (25 years or more). If investments in infrastructure with

high energy demand are made early, the opportunities for reducing GHG emissions

going forward are constrained and it will be more difficult in the future to attain

lower stabilization levels. The risk of severe climate change impacts increases with

later implementation of mitigation strategies.1

Both bottom-up and top-down economic modeling studies indicate that there is a

substantial economic potential for mitigation of global GHG emissions over the coming decades. However, macroeconomic cost estimates are sensitive to assumptions

about rates of technological change, target stabilization level, and whether a multiple gas approach or carbon-only mitigation approach is adopted.

To stabilize GHG concentrations at a level that will avoid the most dangerous

global warming, the Report estimates costs, generated by macroeconomic models,

may vary from a reduction of three percent Gross Domestic Product (GDP) to an

increase of one percent GDP. The reduction in GDP is greater for more stringent

stabilization targets.

Another factor that influences macroeconomic cost estimates is the rate of technological change. Models that assume climate change policy enhances technological

change, revenues from carbon taxes or auctioned permits are used to promote lowcarbon technologies, or that assume a reform of existing taxation policies generally

provide the lower macroeconomic cost estimates. Mitigation strategies that assumed

a multiple-gas approach also resulted in substantially lower costs.

Not surprisingly, changes in lifestyle and behavior patterns of citizens across the

world can contribute to climate change mitigation across all sectors. More wide

spread adoption of existing mitigation practices can also have a positive role (Figure

1). New energy infrastructure investments in developing countries, upgrades of energy infrastructure in industrialized countries, and policies that promote energy security, can, in many cases, create opportunities to achieve GHG emission reductions

compared to baseline scenarios. Additional co-benefits are country specific but often

include air pollution abatement, balance of trade improvement, improvement of

modern energy services to rural areas, and increases in employment opportunities.

Energy Supply

Investment in new energy supply infrastructure is estimated to be over 20 trillion

dollars between now and 2030. The investments made in this time frame will impact GHG emissions for many years due to the expected lifespan of these facilities

(25–50 years). A significant shift in energy supply to low-carbon technology is estimated to take decades even with aggressive incentives to promote them, but would

result in a return to 2005 GHG emission levels by 2030 if the investment patterns

were shifted to favor these technologies. The additional cost to achieve this shift is

estimated to be small—on the order of five to ten percent more than investments

in traditional energy supply technologies.

The pattern of investment will continue to be influenced by the market prices for

fossil fuels. At higher fossil prices alternative energy sources will become more attractive, but other factors influence these decisions also. If higher fossil fuel prices

lead to replacement of conventional oil resources with oil sands, oil shales, heavy

oils, and synthetic fuels from coal and gas, GHG emissions will increase from this

sector unless these facilities are equipped with carbon capture and sequestration

systems.

Working Group III indicates that electricity generated through renewable energy

sources could supply 30–35 percent of the total electricity supply in 2030. The Report concludes that nuclear energy will increase by two percent by 2030 (from 16

percent in 2005). High costs, safety, concerns about weapons proliferation and waste

continue to constrain nuclear energy development.

Working Group III also found energy efficiency investments to be more cost-effective than increasing energy supply to meet energy demand. Efficiency improvements

also deliver benefits in terms of energy security, pollution reduction, and employment.

232

Transportation Sector

Pertaining to the transportation sector, multiple mitigation options exist, although

these solutions must overcome many barriers, such as consumer preferences and

lack of policy frameworks. Improved vehicle efficiency measures, leading to fuel saving, in many cases have net benefits but the market potential is much lower than

the economic potential due to the influence of other consumer considerations, such

as performance and size. It is important to note that Working Group III states that

market forces alone, including rising fuel costs, are not expected to lead to significant emission reductions.

Depending on their production pathway, biofuels might play an important role in

addressing GHG emissions in the transport sector. Biofuels used as gasoline and

diesel additives/substitutes are projected to grow three percent of total transport energy demand in the baseline in 2030. This could increase to about 5–10 percent, depending on future oil and carbon prices, improvements in vehicle efficiency and the

success of technologies to utilize cellulose biomass. Shifts in transportation use from

cars to rail or public transport could provide great benefits to mitigated greenhouse

gas emissions. This trend would further benefit from integrated urban planning to

minimize the need for car travel.

Pertaining to air travel, medium-term mitigation potential for CO2 from the aviation sector could be gained from improved fuel efficiency, which can be achieved

through a variety of means including technology, operations, and air traffic management.

Residential & Commercial Building Sector

Energy efficiency options for new and existing buildings could considerably reduce

CO2 emission with net economic benefit. Many barriers exist against tapping this

potential, but there are also large co-benefits. The barriers to achieving more energy

efficient buildings are higher in developing countries. This is another area where

rapid improvements in building design, development and diffusion of energy efficient building technologies (e.g., heating, cooling, lighting), adequate financing, and

better information would yield benefits in reduced energy demand and GHG emissions. The rate of construction in developing countries is high and investments in

this infrastructure will have an impact on emissions from these areas now and in

the future. Working Group III estimated up to 30 percent of the GHG emissions

could be avoided with net economic benefit by 2030.

Industrial Sector

The economic potential for reducing GHG emissions in the industrial sector is predominantly located in the energy intensive industries. The new facilities in developing countries include new technologies that are more energy efficient and are associated with lower GHG emissions. However, there are many old, inefficient facilities in both the developed and developing countries that, if upgraded, could significantly reduce GHG emissions from this sector. Key barriers to achieving reductions

from this sector include the long life-span of existing facilities, lack of financial and

technical resources, and insufficient access to technological information on strategies

for emission reduction.

Agriculture and Forestry Sectors

Agricultural practices collectively can make a significant contribution at low cost

to increasing soil carbon sinks, to GHG emissions reductions, and by contributing

biomass feed stocks for energy use. The mitigation potential in the agricultural sector is associated primarily with opportunities to increase carbon sequestration and

through reductions in methane and nitrous oxide emissions in specific agricultural

systems.

Working Group III found that biomass can be an important energy feedstock.

However, its contribution to mitigation is dependent upon a variety of factors including the demand for bioenergy from the transport and energy supply sectors,

water availability, and competition with other land uses including production of food

and fiber.

Similarly, forest-related mitigation activities can considerably reduce GHG emissions. Much of the mitigation potential from this sector is located in tropical regions

and half of the potential could be achieved by reducing deforestation. Improved forest management practices could also result in increased CO2 removal from the atmosphere and more sustainable systems with many co-benefits.

Mitigation in the Long-Term: Beyond 2030

As stated earlier, investment choices made in the 2005 to 2030 timeframe will determine the additional emissions reductions required in 2050 and beyond to stabilize

atmospheric GHG concentrations at a level that will avoid dangerous impacts of cliVerDate 11-MAY-2000 16:04 May 12, 2008 Jkt 032966 PO 00000 Frm 00006 Fmt 6601 Sfmt 6621 C:\WORKD\FULL07\020807\32966B.TXT SCIENCE1 PsN: SCIENCE1
233

mate change. Limited, preliminary results from analyses of costs and benefits associated with mitigating climate change indicate they are comparable.

In order to stabilize atmospheric concentrations of GHG, emissions would have to

peak at some level and decline thereafter to achieve the new stabilized concentration. GHGs remain in the atmosphere for a long period of time once emitted and

therefore achieving a lower stabilized concentration will not occur immediately once

emissions are reduced. The current concentration of CO2, the most important GHG

is 379 ppm. Working Group III found that the stabilization levels they examined

are achievable if currently available technologies and the technologies expected to

be commercialized by 2030 are deployed. The technologies and practices predicted

to be available by 2030 are listed in Figure 2.

Decision-making about appropriate level of global mitigation over time involves an

iterative risk management process that includes mitigation and adaptation, taking

into account actual and avoided climate change damages, co-benefits, sustainability,

equity, and attitudes to risk. Choices about the sale and timing of GHG mitigation

involve balancing the economic costs of more rapid emissions reductions now against

the corresponding medium-term and long-term climate risks of delay.

The preferred choice rests on the assumption about the shape of the damage cost

curve associated with increased global average temperature and on the sensitivity

of the climate to continuing increases of GHG emissions. If the relationship between

climate change and the costs associated with damaging impacts is gradually rising

and the changes are predictable and regular in their growth, this would allow for

greater adaptation and would economically justify a later starting date for implementing mitigation measures.

If however, the costs associated with climate change increase rapidly with time

and if the rates of change are not predictable or stable, then earlier and more stringent mitigation strategies are required. Even small probabilities of catastrophic

events such as significant melting of ice sheets in Greenland or Antarctica would

justify earlier and more stringent action.

If climate sensitivity is high, earlier and more stringent implementation of mitigation is required than if climate sensitivity is low. The results from Working Group

II, indicating more rapid and widespread impacts being identified over the past decade suggest the climate sensitivity may be high, especially if GHG emissions continue to grow.

Policies, Measures, and Instruments to Mitigate Climate Change

A wide variety of national policies and instruments are available to governments

to create the incentives for mitigation actions. Their applicability depends on national circumstances and understanding their interactions, but experience from implementation in various countries and sectors shows there are advantages and disadvantages for any given instrument. Policies that provide a real or implicit price

of carbon could create incentives for producers and consumers to significantly invest

in low-GHG products, technologies and processes. Such policies could include economic instruments, government funding and regulation.

Voluntary agreements between governments and industry and voluntary actions

being adopted by corporations, non-governmental organizations, local and regional

234

authorities and other groups may limit GHG emissions and stimulate innovative

policies, but they have had limited impact on national or regional emission levels

and have not resulted in significant reductions of GHG emissions.

Government support through financial contributions, tax credits, standard setting

and market creation is important for effective technology development countries depends on enabling conditions and financing. Figure 3 illustrates possible government actions noted by Working Group III.

Witnesses

Dr. Mark Levine, Division Director of the Environmental Energy Technologies Division at Lawrence Berkeley National Laboratory (LBNL)

Dr. Mark Levine served as a Coordinating Lead Author for Chapter 6 of the report entitled: Specific Mitigation Options in the Short- and Medium-Term—Residential/Commercial Sector (Including Services). Currently, Dr. Levine works as division

235

director of the Environmental Energy Technologies Division at Lawrence Berkeley

National Laboratory (LBNL). He received his Ph.D. in chemistry from UC–Berkeley

and was a Fulbright scholar in Germany. Before joining LBNL in 1978, he was a

staff scientist at the Ford Foundation Energy Project in Washington, D.C., and a

senior energy policy analyst at SRI, International in Menlo Park. Dr. Levine research focuses on energy modeling, appliance energy efficiency policy, and other aspects of energy efficiency and climate change policy analysis. He sits on the boards

of several energy policy organizations, including the American Council for an Energy-Efficient Economy and the Center for Clean Air Policy.

Dr. William A. Pizer, Fellow at Resources for the Future and a Senior Economist at the National Commission on Energy Policy

Dr. William Pizer served as a Lead Author for Chapter 11 of the report entitled:

Mitigation from a Cross-Sectoral Perspective. Currently, Dr. Pizer is a Fellow at Resources for the Future and Senior Economist at the National Commission on Energy

Policy. Dr. Pizer has a B.A. in physics from the University of North Carolina at

Chapel Hill and a Ph.D. and M.A. in economics from Harvard University. Dr. Pizer’s

research seeks to quantify how various features of environmental policy and economic context, including uncertainty, individual and regional variation, technological change, irreversibility, spillovers, voluntary participation, and flexibility, influence a policy’s efficacy.

Recently, Dr. Pitzer’s work has considered the regional variation in household energy use, firm variation in pollution control costs, the effectiveness of voluntary programs, the role of technology programs in pollution control efforts, the relative efficiency of flexible performance standards and intensity targets, and the effectiveness

of regional climate change policies. Since August 2002, Dr. Pizer has worked parttime as a Senior Economist at the National Commission on Energy Policy. During

2001–2002, he served as a Senior Economist at the President’s Council of Economic

Advisers where he worked on environment and climate change issues.

Mr. Steven Plotkin, Transportation Energy and Environmental Systems Analyst at the Center for Transportation Research, Argonne National Laboratory

Mr. Stephen Plotkin served as a Lead Author for Chapter 5 of the report entitled:

Specific Mitigation Options in the Short- and Medium-Term—Transport and Infrastructure. Mr. Plotkin is a transportation energy analyst with the Center for Transportation Research of the Argonne National Laboratory. His recent work focuses on

advanced automotive technology, greenhouse gas reduction strategies, and automotive fuel economy policy. He was a co-principal investigator of the joint U.S. Department of Energy/Natural Resources Canada study, Examining the Potential for

Voluntary Fuel Economy Standards in the United States and Canada and a consultant to the National Research Council’s study on the effectiveness and impact of Corporate Average Fuel Economy (CAFE) Standards. Mr. Plotkin received B.S. in Civil

Engineering from Columbia University and his Masters in Aerospace engineering

and did graduate work in applied physics/aerospace engineering at Cornell University.

Dr. Roger Pielke, Jr., Director, Center for Science and Technology Policy

Research and Professor in the Environmental Studies Program at the University of Colorado

Dr. Roger Pielke is a Professor in the Environmental Studies Program and also

Director, Center for Science and Technology Policy Research. With a B.A. in mathematics and a Ph.D. in political science from the University of Colorado, he focuses

his research on the relation of scientific information and public and private sector

decision-making. His current areas of research are societal responses to extreme

weather events, domestic and international policy responses to climate change, and

United States science policy. Dr. Pielke’s research interests include understanding

natural disasters and climate change, the politicization of science and decision-making under uncertainty.

Definitions

Mitigation Potential: The concept has been developed to assess the scale of GHG

reductions that could be made, relative to emissions baselines, for a given level of

carbon price (expressed in terms of cost per unit of carbon dioxide equivalent emissions avoided or reduced). Mitigation potential is further differentiated in terms of

‘‘market potential’’ and ‘‘economic potential.’’

236

Market Potential: The mitigation potential based on private costs and private discount rates, which might be expected to occur under forecast market conditions, included policies and measures currently in place, noting that barriers limit actual uptake.

Economic Potential: The mitigation potential, which takes into account social

costs and benefits and social discount rates, assuming that market efficiency is improved by policies and measures and that barriers are removed.

Bottom-Up versus Top-Down Studies: Bottom-up studies look at mitigation options emphasizing specific technologies and regulations. In contrast, top-down studies assess the economy-wide potential of mitigation options. Bottom-up studies are

useful for the assessment of specific policy options a sectoral level, while top-down

studies better assess cross-sectoral and economy-wide climate change policies, such

as carbon taxes and stabilization policies.

Greenhouse Gases: Carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O),

hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulphur hexafluoride

(SF6). Water vapor is also a greenhouse gas—the most abundant greenhouse gas in

the atmosphere. However, the concentration of water vapor in the atmosphere has

not been significantly altered through human activities unlike the other above-mentioned greenhouse gases which are associated with fossil fuel production and use,

land-use management and change, and industrial processing and consumer products.

237

Chairman GORDON. This hearing will come to order, and good

morning, everyone. Welcome to the Committee’s third hearing on

the Intergovernmental Panel on Climate Change, Fourth Assessment Report. On May the 4th the third Working Group released a

summary of its chapters on the mitigation of Climate Change in

Bangkok. The summaries of the Working Group I and II released

earlier this year indicated that both adaptation and mitigation

strategies are needed to counteract the effects of increasing greenhouse gas concentration in the atmosphere.

Adaptation strategies can lessen the impact of the challenges in

climate, changes in climate we are experiencing now and that we

will experience under any scenario in the future. However, the

IPCC report tells us that if we are to avoid the dangerous impacts

of climate change associated with global temperature increases of

four degrees or higher, we must develop and implement mitigation

strategies.

Working Group III’s report outlines specific measures that we

can consider to design a path to stabilize and then reduce greenhouse gas emissions. Some are policy measures, others are technological. Not surprising, the report counsels that the earlier we

begin the better chance we have of achieving the goal of avoiding

dangerous impacts of climate change.

Of course, we are all concerned about the cost of achieving this

goal. As we all suspect, this effort will be costly, and the estimates

of these costs vary considerably depending upon the assumption

used in the economic models to generate them. However, in action

is not cost free, either in monetary terms or in human suffering.

Longer, more intense droughts increase flooding and accelerated

sea level rise are all very costly. Increased public health problems

and increased mitigation of environmental refugees are also very

costly as the Pentagon recently pointed out.

While there will be costs, there will also be benefits and opportunities for new jobs and new industries. We simply cannot afford the

cost of inaction, especially when we consider our need to move to

a new generation future to achieve greater national and economic

superiority.

The summary does not point to any single policy or group of technologies that will achieve emission reductions. Each nation and

each region must participate in a global effort to reduce emissions

by developing strategies that will work within their respective economic and social frameworks.

We must do the—for the U.S. the types of analysis performed by

the IPCC for a global basis to understand the cost and benefits associated with alternative mitigation policies and technologies. Time

is the one thing we can never recover.

We have an opportunity if we act now to avoid radical alternations in our world that we will be unable to adapt to or to overcome. We have an obligation to our children and grandchildren to

face the challenge of climate change and deliver them a future that

is an energy security as as we inherited. We can only accomplish

that by diversifying our energy supplies and becoming more energy

efficient.

238

We have the opportunity to lead the world in cooperative effort

to make sustainable development not just a goal but a reality. The

sooner we begin, the better off we will be.

We have a distinguished panel of witnesses here this morning to

discuss the options of mitigating climate change. Welcome to all of

you, and thank you for being here today to discuss this important

topic with the Committee.

[The prepared statement of Chairman Gordon follows:]

PREPARED STATEMENT OF CHAIRMAN BART GORDON

Good morning and welcome to the Committee’s third hearing on the Intergovernmental Panel on Climate Change’s Fourth Assessment Report.

On May 4, the third Working Group released the Summary of its chapters on the

Mitigation of Climate Change in Bangkok. The Summaries of Working Groups I and

II released earlier this year indicated that both adaptation and mitigation strategies

are needed to counteract the effects of increasing greenhouse gas concentrations in

the atmosphere.

Adaptation strategies can lessen the impacts of the changes in climate we are experiencing now and that we will experience under any scenario in the future. However, the IPCC reports tell us that if we are to avoid the dangerous impacts of climate change associated with global temperature increases of four degrees or higher,

we must develop and implement mitigation strategies.

Working Group III’s report outlines specific measures that we can consider to design a path to stabilize, and then reduce, greenhouse gas emissions. Some are policy

measures, others are technological. Not surprising, the report counsels that the earlier we begin the better chance we will have of achieving the goal of avoiding dangerous impacts of climate change.

Of course, we are all concerned about the costs of achieving this goal. As we all

suspect, this effort will be costly and the estimates of these costs vary considerably

depending upon the assumptions used in the economic models to generate them.

However, inaction is not cost-free, either in monetary terms or in human suffering. Longer, more intense droughts, increased flooding, and accelerated sea level

rise are all very costly. Increased public health problems and increased migration

of environmental refugees are also very costly.

While there will be costs, there will also be benefits and opportunities for new jobs

and new industries. We simply cannot afford the costs of inaction, especially when

we consider our need to move to new energy future to achieve greater national and

economic security.

The Summary does not point to any single policy or group of technologies that

will achieve emission reductions. Each nation and each region must participate in

a global effort to reduce emissions by developing strategies that will work within

their respective economic and social frameworks.

We must do for the U.S., the types of analyses performed by the IPCC on a global

basis, to understand the costs and benefits associated with alternative mitigation

policies and technologies.

Time is the one thing we can never recover. We have an opportunity, if we act

now, to avoid radical alterations in our world that we will be unable to adapt to

or overcome. We have an obligation to our children and grandchildren to face the

challenge of climate change and deliver them a future that is as energy secure as

the one we inherited. We can only accomplish that by diversifying our energy supplies and becoming more energy efficient.

We have an opportunity to lead the world in a cooperative effort to make sustainable development not just a goal, but a reality. The sooner we begin, the better off

we will be.

We have a distinguished panel of witnesses here this morning to discuss the options for mitigating climate change. Welcome to all of you, and thank you for being

here today to discuss this important topic with the Committee.

Chairman GORDON. At this time I am pleased to yield to distinguished Ranking Member Mr. Hall, for an opening statement.

Mr. HALL. I thank you, Mr. Chairman, and I am really pleased

that you are holding this hearing today, because it provides all of

us with an opportunity to discuss what I believe and others of us

believe this committee should focus on when it comes to the issue

239

of global climate change and how much it is going to cost and what

do we get in return.

The key question I think facing all of us here in Congress is not

what does the latest science say about climate change. The key

question is given all the science what is the appropriate policy for

the United States to move our Nation towards affordable, and I repeat again, affordable, reliable, and clean energy sources.

It is not an easy question to answer. We have to consider if the

U.S. regulates greenhouse gases what impact could we have on

other major carbon-emitting countries who do not follow suit.

Would this reality put America in the position of shouldering the

burden of cleaning up the world and having our citizens bear the

high cost? What would regulations mean for the price of natural

gas, for example, for electricity rates? Are these costs we are willing to accept if given the uncertainty about whether regulations

could help them? Do you think we would accept them?

When I return to my Congressional district, constituents have

high on their list the high cost of gasoline. We need to be looking

to ways to lower this cost, not raise it, and yet the scenarios being

discussed here today propose raising the price of gasoline substantially. Estimates of price increases range from 20 cents per gallon

to as much as a dollar per gallon. Rather than focusing on ways

to raise energy prices for Americans, we ought to be discussing

what the United States could accomplish with the right investments in energy research and energy development. We have to consider the enormous benefits and the cost of adaptation, and we

must not lose sight of other pressing national priorities and understand the overall burden of all the national needs to the average

citizen.

Work Group III was asked to look at ways to mitigate greenhouse gases, and that is what they did. I think their charge was

too narrow and should have included a more comprehensive assessment to help us answer the questions I mentioned earlier. Policymakers should not make decisions in a vacuum, and so it would be

more useful if the technical information presented to us was placed

in a broader context.

Nevertheless, they did what they did under the charge that they

were given. The Working Group III report points out that even a

middle of the road greenhouse gas mitigation approach would mean

a reduction of up to four percent of global GDP.

Let me place that in context for you. At the end of the first quarter of 2007, the U.S. GDP was $13.6 trillion. Four percent of that

is $544 billion. Now, remember that figure, $544 billion. By comparison total United States spending on defense in FY 2004, was

$567 billion, just a little bit over the four percent that I am asking

you to compare with.

The American Competitiveness Initiative when complete in FY

2016, will total only $19 billion, just a fraction of one percent of the

U.S. GDP. One hundred and forty-three billion is the total Federal

R&D investment in FY 2007. Nationwide education spending, for

federal, State, and local combined as a percent of GDP is 5.7 percent.

240

Finally, the entire budget for the Social Security Administration is on the order of $600 billion. Now, compare those, and what do

you think of those comparisons?

Mr. Chairman, now that all three groups of the IPCC have reported, I look forward to the real discussion that the Committee

should promote. We should be the leader in the House of Representatives for promoting wise investments in energy research

and development, investments that tap into America’s innovative

spirit, and lead us to a future where our energy supply is affordable, reliable, and clean, and I add again affordable.

I yield back the balance of my time.

[The prepared statement of Mr. Hall follows:]

PREPARED STATEMENT OF REPRESENTATIVE RALPH M. HALL

Thank you Mr. Chairman. I am glad that you are holding this hearing today because it provides all of us with an opportunity to discuss what I believe this committee should focus on when it comes to the issue of global climate change—how

much is it going to cost and what do we get in return.

The key question facing all of us here in Congress is not ‘‘What does the latest

science say about climate change?’’ The key question is ‘‘Given all the science, what

is the appropriate policy for the United States to move our nation towards affordable, reliable and clean energy sources?’’ It is not an easy question to answer. We

must consider if the U.S. regulates greenhouse gases, what impact could we have

if other major carbon emitting countries do not follow suit? Would this reality put

America in the position of shouldering the burden of cleaning up the world and having our citizens bear the high costs? What would regulations mean for the price of

natural gas? For electricity rates? Are these costs we are willing to accept given the

uncertainty about whether regulations could help?

When I return to my congressional district, constituents have high on their list

of concerns the high price of gasoline. We need to be looking at ways to lower this

cost, not raise it. And yet, the scenarios being discussed today propose raising the

price of gasoline substantially. Estimates of price increases range from 20 cents per

gallon to as much as $1.00 per gallon.

Rather than focusing on ways to raise energy prices for Americans, we must discuss what the U.S. could accomplish with the right investments in energy research

and development. We must consider the enormous benefits and lower costs of adaptation. And, we must not lose sight of other pressing national priorities and understand the overall burden of all national needs on the average citizen.

Working Group III was asked to look at ways to mitigate greenhouse gases, and

that’s what they did. I think their charge was too narrow and should have included

a more comprehensive assessment to help us answer the questions I mentioned earlier. Policy-makers should not make decisions in a vacuum, and so it would be more

useful if the technical information presented to us was placed in a broader context.

Nevertheless, they did what they did under the charge given to them.

The Working Group III report points out that even a middle of the road greenhouse gas mitigation approach would mean a reduction of up to four percent of global GDP. Let me place that in context for you. At the end of the first quarter of 2007,

the U.S. GDP was $13.6 trillion. Four percent of that is $544 billion. By comparison:

• Total U.S. spending on defense in FY 2007 ($567 billion) will be close to four

percent of U.S. GDP.

• The American Competitiveness Initiative, when complete in FY 2016, will

total $19.5 billion, just a fraction of one percent of U.S. GDP.

• $143 billion is the total Federal R&D investment in FY 2007.

• Nationwide education spending (federal, State and local combined) as a percent of GDP is 5.7 percent.

• Finally, the entire budget for the Social Security Administration is on the

order of $600 billion.

Mr. Chairman, now that all three groups of the IPCC have reported, I look forward to the real discussion this committee should promote. We should be the leader

in the House of Representatives for promoting wise investments in energy research

and development, investments that tap into American’s innovative spirit and will

lead us to a future where our energy supply is affordable, reliable and clean.

241

I yield back the balance of my time.

Chairman GORDON. Thank you, Mr. Hall, and I just want to remind you that out of the Subcommittee this week we passed the

ARPA–E bill. We will have an opportunity to carry out your wishes

next week when the ARPA–E bill will be on, which will be the most

cutting-edge effort to do that kind of technology investment at, as

you pointed out, a very modest way.

Yes, sir, Mr. Hall. Did you——

Mr. HALL. I respect you and respect your position, and I look forward to next week.

Chairman GORDON. Thank you, sir. And if there are Members

who wish to submit additional opening statements, your statements will be added to the record.

[The prepared statement of Mr. Costello follows:]

PREPARED STATEMENT OF REPRESENTATIVE JERRY F. COSTELLO

Good morning. I want to thank Chairman Gordon for holding today’s hearing on

the third section of the 2007 Fourth Assessment Report, Climate Change 2007: Climate Change Impacts, Adaptation and Vulnerability, prepared by Working Group

III of the Intergovernmental Panel on Climate Change (IPCC). The report offers key

findings of the current state of scientific knowledge on strategies to mitigate climate

change and provides Congress with additional information on global warming.

As Congress begins to develop legislation to address climate change, we cannot

ignore the reality that coal is going to play a role in our nation’s energy supply and

the world energy supply for years to come. Coal generates half of the electricity in

this country and is a reliable domestic source of power with a 250-year supply of

coal in the U.S. alone. To fully maximize our use of coal, we must continue to take

steps that reduce emissions. The only way to achieve this goal is through advancements in technology. I have been a strong supporter of clean coal initiatives and programs to advance the research and development needed to improve coal-based electricity generation. Congress must continue to support the clean coal programs in the

President’s FY08 budget, which includes the FutureGen Project, slated to be the

world’s first zero-emissions coal plant. Among other things, FutureGen will demonstrate the ability to sequester carbon dioxide emissions safely underground. The

more coal plants using clean coal technology equals reduced greenhouse gas emissions.

Clean coal technologies do exist; however, they need the support and backing from

Congress to further develop and demonstrate their commercial viability. As we consider climate change legislation, I encourage my colleagues to include coal as part

of our energy solution. Again, I look forward to working with my colleagues as we

find practical solutions that lead us down the path of energy independence and protection of our environment.

I welcome the panel of witnesses and look forward to their testimony.

[The prepared statement of Ms. Johnson follows:]

PREPARED STATEMENT OF REPRESENTATIVE EDDIE BERNICE JOHNSON

Thank you, Mr. Chairman. I would like to welcome today’s witnesses to our hearing on the third section of the Intergovernmental Panel on Climate Change 2007

Fourth Assessment Report.

Entitled, ‘‘Climate Change 2007: Mitigation of Climate Change,’’ the report was

prepared by Working Group III of the IPCC.

Mr. Chairman and colleagues, you may know that I chair the Subcommittee on

Water Resources and Environment, of the House Transportation Committee.

This position places me at the intersection of water resources and the environment’s sensitivity to climate change.

Texas’ growing population is putting stress on the quality and effects of its precious water resources.

The Environmental Protection Agency estimates that Texas could see a temperature increase by four degrees Fahrenheit by 2100 if we continue along the predicted

global warming path.

The result, Mr. Chairman, will be hotter, drier Texas summers, with greater

threats of severe wildfires. Droughts will worsen and flooding will become more of

242

an issue. Rising sea levels may affect people and animals living near the coastal

zones.

The E.P.A. itself estimates that it could cost up to $12.9 billion to protect the

Texas coast from a 20-inch rise in sea level.

There are other effects predicted for Texas as well, such as a loss of its brown

shrimp population and shrinking barrier islands.

Mr. Chairman, it is disturbing to know that these climate changes have resulted

from human activities, and further damage is on the horizon.

Today’s witnesses will present the summary of a large volume of scientific information from delegates from more than one hundred nations.

Importantly, the report provides mitigation options for the main economic sectors

in the near-term and also provides information on long-term mitigation strategies.

The report also discusses the implications of different short-term strategies for

achieving long-term goals.

It is my hope that this information will better inform policy-makers so that we

can spur change.

Again, welcome to today’s witnesses. Thank you, Mr. Chairman. I yield back.

Chairman GORDON. And at this time I would like to introduce

our witnesses. First, Dr. Mark Levine served as the Coordinating

Lead Author for Chapter 6, Specific Mitigation Options in the

Short- and Medium-Term—Residential and Commercial Sector of

the Working Group III report. Currently Mr. Levine works as the

Division Director of the Environmental Energy Technology Division

at Lawrence Berkeley Laboratory.

Our next witness will be Dr. William Pizer. He served as the

Lead Author for Chapter 11, Mitigation from a Cross-Sectoral Perspective of the Working Group III report. Dr. Pizer is a fellow at

Resources for the Future and senior economist at the National

Commission on Energy Policy.

Dr.—or rather Mr. Steven Plotkin served as the Lead Author of

Chapter 5 of the report entitled, Specific Mitigation Options in the

Short- and Medium-Term—Transport and Infrastructure. Mr. Plotkin is a transportation energy analyst with the Center of Transportation Research at the Argonne National Laboratory.

And finally, Dr. Roger Pielke, Jr. is Professor of Environmental

Studies Program at the University of Colorado and Director of the

Center for Science and Technological Policy Research.

As our witnesses should know that we try to limit our spoken

testimony to five minutes, but this is an important hearing, and we

want you to be judicious but to take what time you need, and we

will start with Dr. Levine. Thank you for being here.

STATEMENT OF DR. MARK D. LEVINE, DIVISION DIRECTOR OF

THE ENVIRONMENTAL ENERGY TECHNOLOGY DIVISION AT

LAWRENCE BERKELEY LABORATORY

Dr. LEVINE. Thank you, Mr. Chairman, and distinguished Members of the Committee. I greatly appreciate your holding this hearing on this important topic. I am honored to be here today to speak

to you.

As you pointed out, I am a senior staff scientist at Lawrence

Berkeley National Laboratory, former division director, but I speak

to you in my capacity as Coordinating Lead Author of Chapter 6

of Working Group III of the 4th assessment report.

I was asked to address two questions. The first was to describe

to you the findings from Chapter 6, Specific Mitigations in the

Short- and Medium-Term for Residential and Commercial BuildVerDate 11-MAY-2000 16:04 May 12, 2008 Jkt 032966 PO 00000 Frm 00016 Fmt 6601 Sfmt 6601 C:\WORKD\FULL07\020807\32966B.TXT SCIENCE1 PsN: SCIENCE1
243

ings, and second, to explain how these findings differ from previous

assessments.

I think this chapter is particularly interesting in light of the

opening comments that we have heard because buildings represent

an opportunity to reduce, to mitigate carbon dioxide emissions cost

effectively, so that, in fact, the concern that you may have about

impacts on the economy need not be concerns if one does energy

efficiency cost effectively and there are numerous opportunities to

do so in the building sector.

The Summary for Policy-makers notes that energy efficiency options for new and existing buildings should considerably reduce

CO2 emissions with net economic benefits. It goes on to estimate

that by 2030 one could achieve 30 percent reduction in emissions

due to energy use associated with buildings if one were able to tap

into all cost-effective measures. Of course, tapping into all these

measures is no easy job, and the report points out the numerous

barriers that exist to obtaining these measures in the marketplace.

It also notes that it is particularly difficult for many developing

countries to overcome the many barriers to energy efficiency in

buildings.

Let me make a few comments on the findings. The most, there

are several significant features of this report. The first is that the

full report of 90 pages underwent extensive review by Governments, by experts, and so I view the report as as authoritative review of the literature as one can find, far more than my colleagues

and I could ever have accomplished. It is a long and torturous process at the IPCC, but it does give quality and works very hard to

remove bias.

My second comment has to do with the contribution of the report

to reviewing the different bottom-up studies of energy efficiency potential in buildings. By bottom-up I mean a characterization of the

key technologies that can reduce carbon dioxide emissions, their

costs, and the quantity of emission reductions that can be achieved

through time. The analysis involved a review of 80 studies and a

thorough assessment of 17 of these. These studies covered the

globe. This is the first time that a thorough analysis of these types

of studies have ever been done, and this analysis gives me confidence that we are working on a body of literature that is, in fact,

meaningful. I have been troubled for many years working in the

field, not knowing what really was understood out there in work

carried out in many other countries. So this, I think, is a significant achievement.

Second observation from the study is that this 30 percent reduction, if you could achieve it, is comparable to a 30 percent increase

that would be projected in the lowest of the scenarios that we are

looking at and comparable to about a 45 percent increase in a typical scenario that we are looking at. So that it is within the realm

of the possible that this cost-effective potential, a potential, Mr.

Hall, that would not for the case of buildings, cause damage to the

economy, could be achieved without increasing emissions. But, of

course, it depends on the scenario itself, and those results would

be less significant if the scenario is higher.

On the other hand, it is important to note that 70 percent of electricity is used in buildings, and as we decarbonize electricity, that

244

reduces emissions from buildings. Now, there you get into carbon

charges. If you want to decarbonize electricity, then it is likely that

you will have to talk about certain carbon charges.

Finally, I want to observe that notwithstanding these opportunities the policies necessary to bring about these major reductions

are very substantial, and the study identified many policies that

were, in fact, quite effective in different places, but it did not identify any silver bullets, any policies that were effective broadly, but

it did show quite a number of effective policies.

Now, I have spent most of my time I think. Let me conclude with

your last question. How does this compare with the previous assessments? The third assessment report devoted very little attention to this topic, so I almost want to skip it except that it came

up with some estimates that said, well, we could, in fact, achieve

emissions at 1998, levels in 2010, 2020, and 2050, but those were

admittedly guesses of the team. And so we give them low evidence

and low agreement in our terminology for how much we, how much

credibility we want to place on those results. And that is about it

for that report.

In the second assessment report these was a thorough descriptive

description of technologies, a description of policies but no evaluation, and the reason for that was that the world hadn’t moved toward energy efficiency far enough at that point to be able to do

evaluation.

But I think my final, my major conclusion is that the world has

come a long way. There is really no contradiction among the assessment, but we have seen an evolution of knowledge over time

as different countries, different regions, different, indeed, different

cities, have implemented different policies and different technologies for a greenhouse gas mitigation in the building sector.

Thank you very much.

[The prepared statement of Dr. Levine follows:]

PREPARED STATEMENT OF MARK D. LEVINE

Introduction

Mr. Chairman and distinguished Members of the Committee, thank you for holding this important hearing. It is my honor to be here today and I hope that I can

be helpful to you and your staff as the Committee considers the findings of the report and work to address its policy implications.

My name is Mark Levine and I am a senior scientist at the Lawrence Berkeley

National Laboratory and formerly the Division Director for the Lab’s Environmental

Energy Technologies Division. However, my testimony here today is not on behalf

of the Laboratory, but rather as a participant in the IPCC Working Group III on

mitigation.

I was the Convening Lead Author for the Second Assessment Report for the Chapter on GHG emissions on buildings and was the Co-coordinating Lead Author for

the 4th Assessment for the same topic (with Professor Diana Urge-Vorsatz of the

Central European University, Hungary). I am testifying in this role, on my own behalf and as a result of my expertise in this role.

The Committee has asked me address two issues. First, to discuss the findings

from Chapter 6, Specific Mitigations in the Short- and Medium-Term—Residential/

Commercial Sector. And, second, to explain how the findings of this Fourth Assessment report differ from those of the previous Assessments of Mitigation of Climate

Change.

I am interpreting the second question narrowly, as it relates to Chapter 6—the

area of my direct expertise.

245

Major findings of Chapter 6

The highest level findings from Chapter 6 are contained in the Summary for Policy-Makers (SPM). The SPM notes that ‘‘energy efficiency options for new and existing buildings could considerably reduce CO2 emissions with net economic benefit.’’

It goes on to state that ‘‘(m)any barriers exist against tapping this potential, but

there are also large co-benefits (high agreement, much evidence).’’ In summary the

working group found that:

• By 3030, about 30 percent of the projected GHG emissions in the building sector can be avoided with net economic benefit

• Energy efficient buildings, while limiting CO2 can also improve indoor and

outdoor air quality, improve social welfare and enhance energy security

• Opportunities for realizing GHG reductions in the building sector exist worldwide. However, multiple barriers make it difficult to realize this potential.

These barriers include availability of technology, financing, poverty, higher

costs of reliable information, limitations inherent in building designs and appropriate portfolio of policies and programs.

• The magnitude of the above barriers is higher in the developing countries and

this makes it more difficult for them to achieve the GHG reduction potential

of the building sector.

Commentary on Findings

These findings have been agreed to by all of the countries at the meeting, after

a line by line review. It is fair to say there is unanimity among a diverse body with

representatives of all major countries of the world. This careful review, supported

by a great deal of background work, gives these findings standing in the international community. The full chapter on buildings is 90 pages of detailed text and

references. It has been subject to extensive review by experts and governments before the IPCC meeting that concluded on May 4.

There is significance in the findings that may not be apparent. 30 percent of projected CO2 emissions can be avoided at net economic benefit. This occurs when costeffective investments are made in energy efficiency. Such investments are beneficial

to the consumer, who gains more than she or he pays on an annualized basis, as

well as to society.

An important contribution of the AR4 was its thorough review and effort to put

on a common footing the different ‘‘bottom-up’’ studies of energy efficiency potential

in buildings. By ‘‘bottom-up’’ is meant a characterization of the key technologies that

can reduce carbon dioxide emissions, their cost and the quantity of emissions reductions that can be achieved throughout time. The analysis involved a review of 80

studies and a thorough assessment of 17 of these. Such an extensive comparison of

the major ‘‘bottom up’’ analyses had never been done before, nor had they been applied to cover the globe. This effort alone has added a great deal of confidence to

the analysis of emissions reductions.

It is important to ask how far this energy efficiency will get us in the direction

of climate stabilization. To simplify the discussion, I address the question of the degree to which emissions in 2030 might, through energy efficiency alone, be equal

to those in 2004. Scenario B2 (one of the two commonly used cases) has ∼30 percent

higher emissions in 2030 than in 2004 (11.4 Gt/yr vs. 8.6 Gt/yr). Applying all costeffective mitigation options to buildings would result in constant emissions throughout the period for a B2 baseline scenario. By comparing this result with Figures

SPM 7 and 8, this level (if achieved by all other sectors) is consistent with Stabilization Scenarios II and III, 500–550 ppm CO2 eq. These stabilization levels result in

about three degree Centigrade temperature increase.

There are at least three factors that affect these conclusions relating to how much

buildings can contribute to mitigation of carbon dioxide:

• The baseline may grow faster or slower than B2 which we have chosen. The

baselines studies on which the buildings energy and carbon potential were assessed depended on assumptions in the individual studies we reviewed. Overall, they saw a CO2 emission growth from 8,6 Gt CO2/yr in 2004 to 14.3 Gt/

yr in 2030. (In the B2 scenario, the growth was to 11.4 GT/yr in 2030. In A1B,

the other often cited case, the growth was to 15.6 Gt/yr in 2030.) Using the

middle baseline, buildings-related CO2 would grow to1.4Gt/yr more by 2030

than in 2004 (or 16 percent above 2004 levels) with all cost-effective energy

efficiency.

• The supply side can contribute considerably to CO2 reductions. In the United

States, 70 percent of total primary energy used in buildings is electricity. Any

246

1 I should note that I was a lead author in the TAR and a convening and coordinating lead

author in the SAR and AR4. Thus, I am in a good position to observe the evolution of the reviews over a fifteen year period.

decarbonization of the fuel used to generate electricity translates directly into

lower emissions resulting from energy use in buildings. This suggests that

over time as more low-carbon supply options become available for electricity

generation, energy-related emissions in buildings will decline.

• Notwithstanding these opportunities, a general concern needs to be raised

about the fraction of the cost-effective potential that can be realized in this

time frame. This will depend a great deal on policies that countries have chosen to implement, and the willingness of citizens to spend time and money

on energy efficiency,

This brings us to the issue of policies. The current report reviews performance of

a large number of policies in many countries. No single policy is seen to work everywhere. Yet, unlike the previous assessments, there is evidence of considerable success with individual policies in different places. We have reviewed programs aimed

at the whole building: building codes; building certification and labeling programs;

and education, training, and energy audits. We have reviewed programs aimed at

appliances, lighting, and plug loads: standards and labeling; voluntary agreements.

We have studied cross-cutting programs, including utility demand-side management

programs; elimination of energy subsidies; creation of financial incentives for energy

efficiency; public sector leadership and procurement programs; promotion of Energy

Service Companies; energy efficiency obligations and tradable energy-efficiency certificates; and Kyoto Protocol’s Flexibility Mechanism. All of these—which the exception of the last which does not apply to the United States—has a realm in which

it is highly effective in bringing forth energy efficiency. In addition, to be successful

in mitigating emissions over time, the report notes the importance of expanding

R&D efforts.

Findings from Previous Assessments1

The previous assessment (the Third Assessment Report TAR) devoted little attention to sectoral analyses of GHG mitigation. In spite of this cursory assessment, the

report did estimate that the buildings sector had the potential to achieve levels of

carbon emissions in 2010, 2020, and 2050 that were roughly equal to those in 1998

(Synthesis Report, IPCC TAR, pages 315 and 316). These estimates are similar to

those obtained in AR4—somewhat more optimistic depending on the baseline assumption. However, they are based on very little evidence, as much less rigorous

literature review was conducted to support the findings. They were largely based

on expert judgment.

The Second Assessment Report, on the other hand, devoted a full chapter to mitigation of greenhouse gas emissions from buildings. The chapter provides a description of technologies for energy efficiency in buildings. It is not as complete nor as

rich as in the AR4. The chapter describes the key policies and programs that had

been attempted to that time. In general, the policies were well described in the report, but there was much less information available about evaluation of policy results. While this area has improved in the AR4, it is still evident that evaluation

of policies and programs is not adequate. The SAR does not attempt an evaluation

of bottom-up assessments. It reviews several scenarios that project additional energy efficiency as compared with baseline cases, but is not able to pull out of them

any direct information about emissions reductions from buildings.

Conclusions

I do not find anything contradictory among the three assessments. In reviewing

the SAR, I am struck by how little information on economics or projected savings

was in that report. It was primarily focused on describing what was known about

energy use in buildings, including data on how energy has been used in the buildings sector. But there was little information that might be seen as policy relevant.

The TAR provided much less information. But the authors were willing to make

guesses on the potential for emission reductions at cost-effective levels. These were

based on a given baseline and a very small number of studies that were cited in

the chapter. Thus, it would not have been possible for policy-makers to place much

reliance on the mitigation potentials from the TAR.

AR4 has come the farthest in generating information that can be useful for policymakers. We can be certain that there are many technologies to reduce emissions.

Many of these are described in depth in the report. There is experience with a wide

range of policies and programs, some of which have shown considerable success in

247

individual countries. The report casts a broad net in assessing mitigation potential

in the sector and finds consistency among many different studies in different countries.

There remain major shortcomings. The mitigation potential studies are still too

limited in technology scope and much effort was needed in putting them on a relatively consistent basis. These studies focus attention on technologies that are available today. They shed little light on the question of the magnitude of energy savings

and CO2 mitigation possible as a function of higher carbon charges. This is because

there are so many energy efficiency options available that are presently not being

adopted that the authors do not address advanced technology.

There is one other important point to make about the sector. Unlike the supply

sector, where carbon charges will be needed to bring about adoption of certain advanced technologies, the buildings sector generally needs targeted policies—including regulatory policies and market based approaches—to achieve mitigation goals.

This is because of the large number of barriers that exist in the marketplace that

deter investment in energy efficiency.

BIOGRAPHY FOR MARK D. LEVINE

Mark D. Levine, Director Emeritus of the Environmental Energy Technologies Division at Lawrence Berkeley National Laboratory, has returned to full-time leadership of the China Energy Group Leader in March, 2007. While serving as Division

Director, 1996–2007, Dr. Levine led the division to a doubling of funding during periods of declining federal funds. The Division has a staff of about 450 researchers

and support staff. The research is on energy efficiency technology for buildings, indoor air quality, and other key clean energy technologies (advanced batteries and

low NOΧ combustion). The Division is an international leader in analysis of key national and energy efficiency policy-related issues.

His major passion in the past two decades has been energy efficiency in China.

He again leads the China Energy Group full-time at LBNL since turning over responsibility for the larger Division. The China Energy Group works closely with tens

of leading institutions concerned with energy efficiency and hundreds of researchers

and policy-makers on the topic in China. It has played a leading role in collaborations leading to appliance efficiency labels and standards, targets for industrial energy efficiency, improved energy scenarios and data, building energy standards, and

a host of other activities promoting energy efficiency in China.

Dr. Levine leads prominent national and international non-profits in energy and

environment. He is Board Chair (Center for Resource Solutions), Board Member

(American Council for an Energy Efficient Economy, Center for Clean Air Policy,

Shanghai Pacific Energy Center, and the California Clean Energy Fund), and Member of Advisory Boards (Asian Pacific Energy Research Center in Tokyo and Beijing

Energy Efficiency Center). He is a delegate to and Coordinating Lead Author for the

Intergovernmental Panel on Climate Change.

He has authored more than 100 technical publications, most relating to energy

efficiency and methods of reducing carbon emissions to the atmosphere. Dr. Levine

was co-leader of the report ‘‘Scenarios for a Clean Energy Future’’ as well as a coleader of a recent study of energy and carbon futures of China. He was also a Lead

Author of sections on mitigation for the 1995 and 2001 report of the Intergovernmental Panel on Climate Change. He has led a major international study for the

World Energy Council on energy efficiency.

In 1999, he was elected to be a fellow of the California Council on Science and

Technology, California’s equivalent to the National Academy of Sciences. He graduated summa cum laud from Princeton University and received Fulbright and

Woodrow Wilson fellowships. He holds a Ph.D. from UC–Berkeley.

Chairman GORDON. Dr. Pizer.

STATEMENT OF DR. WILLIAM A. PIZER, FELLOW AT RESOURCES FOR THE FUTURE AND SENIOR ECONOMIST AT

THE NATIONAL COMMISSION ON ENERGY POLICY

Dr. PIZER. Thank you, Mr. Chairman, for the opportunity to talk

about the recent IPCC report.

Let me just start by saying the summaries I am going to give you

here today are not necessarily reflecting the opinions of my colleagues at Resources for the Future, which is an organization that

248

does research on environment, energy and natural resource questions but does not take positions on matters of public policy. It also

does not necessarily reflect the opinions of all my co-authors. There

were more than a dozen authors on my chapter of the IPCC, and

the report reflects all those different perspectives, and I will be

sharing some of my own personal views as I summarize the report.

If I try to summarize the conclusions of the report about the

costs of mitigation on the overall aggregate level, the way I think

about it is the following. There are a variety of different stabilization targets we could think about over the next century, ranging

from doing absolutely nothing and at the end of the century looking

at somewhere between perhaps a three- and seven and one-half-degree Celsius increase in temperatures, or we could do something

really aggressive and try to stabilize concentrations at almost current levels and have very rapid reductions in emissions.

Now, obviously, the cost of doing nothing, if we ignore the environmental consequences that were mentioned earlier in terms of

costal impacts and ecosystems and health and food and things like

that, if we ignore those sorts of impacts, and we do nothing, the

cost is going to be nothing.

On the other hand, if we do something aggressive like try to stabilize concentrations rapidly, try to avoid more than two degrees of

warming globally, well, the report suggests that the cost could be

perhaps as much as three percent of global income in the year

2030. If we think about up to three percent, the report actually

doesn’t have a lot of data on what the costs of stabilization are at

these very low levels. There is a lot more data on things in the

middle, and there the estimates range from something like a sixtenths of a percent increase, that is a net gain to the global economy, to somewhere up to about a two and one-half percent cost of

income.

If we compare these estimates to the last assessment report as

Dr. Levine just did, the main difference is that the new report suggests these very low and possibly negative costs, that is, maybe a

six-tenths of a percent gain to the global economy. And the reason

for this is that the new report considers models, first of all, which

incorporate more of the energy efficiency opportunities that Dr. Levine mentioned, and they also include the possibility that new energy technologies could have very broad economic benefits; things

like, you know, the Internet or mobile technologies that really advance overall economic growth.

So if I look at these conclusions and I try to think about observations, there are really four that I would like to make in my opening

remarks, and they concern uncertainty, the need for public support

for R&D, the need for or the importance of efficient global solutions, and last but not least, trying to put these into maybe a more

accessible framework. So let me just quickly go through those.

First of all, uncertainty, an important thing to realize, this range

of estimates that I just gave you is not actually, does not have a

probability associated with it. The cost could actually be higher or

lower, and the reason is is that this is a collection of best guesses.

And if you think about, for example, your office basketball pool, you

know, most of the people bet on the top seeds. Right? Well, in eight

of the last 29 championship games someone other than the top two

249

seeds have won. So what that means to me is when you look at a

collection of best estimates, it is a good way to predict the likely

outcome, but there is also a reasonable chance there is going to be

something else happening. And in terms of thinking about policies

to deal with climate change, it is very important to think about

what is going to happen if our best pick does not end up being

right.

The second observation concerns technology, and I mention that

the low-cost estimates that we have seen in the recent report hinge

on energy efficiency opportunities, as well as the opportunity for

new technologies to lead to broad economic benefits. And one of the

potential problems, for example, is that as we invest in these new

technologies that have broad economic benefits, we may be taking

away from other technologies that also have broad economic benefits. So to me the lesson and the lesson in the report is actually

the need for broad public support of research and development,

very much like the ARPA–E Policy that has come out of this committee.

The third observation I would make is that all the estimates in

this report emphasize the need for broad, flexible global solutions.

Hence, to the extent we don’t have those solutions, it is going to

be more expensive. So to me the lesson for public policy in the

United States is to think about broad, flexible, domestic policies

and engagement with the rest of the world to try to get similar

policies elsewhere.

The last thing I want to mention is that if you want to try to

make sense of these cost estimates, things like two percent of global income or something like that, I think a useful thing to do is to

try to break it down to what it means for a household. If we think

about what household income is likely to be in the year 2030,

where a lot of these cost estimates focus, the median household is

probably going to be around $55,000 per household, that is, half

the households will be more wealthy and half will be poorer.

If you take half a percent of global income and apply it to that

household, it would be about $275, and that is kind of the moderate approach to stabilization. If you take the more aggressive approach, it would be something more like $1,650. You could also

turn that into prices. The more aggressive approaches, trying to

limit warming to two degrees, would be something like a dollar per

gallon of gasoline or maybe several cents per kilowatt hour. The

more moderate proposals would be something like 20 cents a gallon

of gasoline and maybe one cent per kilowatt hour.

So to me if you are going to try to make a decision about what

sorts of long-term stabilizations to go for, you have to look at these

costs and weigh them against the benefits that we are getting,

somewhere in the middle, maybe a two to five degree likelihood of

warming, or something more aggressive that would really limit

warming to being less two degrees.

So in summary I would just emphasize that the report has a

range of estimates, and if we are thinking about policies, we need

to think about policies that are going to be responsive to, you know,

unlike the outcomes that it is more or less expensive. We need to

deal with the fact that technology is very expensive, and we can’t

just set a cap and trade in motion and go home. We are really

250

going to need public support for R&D. Third, that we need to pursue broad and flexible domestic policies and engage the rest of the

world, and last of all, to make some sort of choice about stabilization. We are going to need to come to grips with how much we

want to reduce the risk of climate change and how much we are

willing to spend.

Thank you.

[The prepared statement of Dr. Pizer follows:]

PREPARED STATEMENT OF WILLIAM A. PIZER

Thank you, Mr. Chairman, for the opportunity to offer testimony before the committee on the Working Group III contribution to the IPCC Fourth Assessment Report: Climate Change 2007: Mitigation of Climate Change, on which I served as one

of more than 100 lead authors. Over the past decade, I have had the privilege of

working on energy and environment issues for organizations as diverse as the President’s Council of Economic Advisers and the National Commission on Energy Policy.

Currently, I am a senior fellow at Resources for the Future (RFF), a 55-year-old research institution headquartered here in Washington, D.C., that specializes in energy, environmental, and natural resource issues. RFF is both independent and nonpartisan and shares the results of its economic and policy analyses with members

of all parties, environmental and business advocates, academics, members of the

press, and interested citizens. RFF neither lobbies nor takes positions on specific

legislative or regulatory proposals, although individual researchers are encouraged

to express their opinions, which may differ from those of other RFF scholars, officers, and directors. I emphasize that the views I present today are mine alone and

do not necessarily reflect those of any group with which I am affiliated, including

the IPCC.

On May 4, the IPCC released the Fourth Assessment Report (AR4) Working

Group III Summary for Policy-makers (SPM). While the underlying report contains

literally hundreds of pages surveying estimates of mitigation costs over the past six

years, three tables in the SPM summarize this information, reproduced below.

Those tables are then further summarized in the text of bullet points #5 and #6:

• Both bottom-up and top-down studies indicate that there is substantial economic potential for the mitigation of global GHG emissions over the coming

decades, that could offset the projected growth of global emissions or reduce

emissions below current levels.

• In 2030 macro-economic costs for multi-gas mitigation, consistent with emissions trajectories towards stabilization between 445 and 710 ppm CO2-eq, are

estimated at between a three percent decrease of GDP and a small increase,

compared to the baseline. However, regional costs may differ significantly

from global averages.

It goes without saying that condensing information so dramatically can leave the

end product open to misinterpretation. The further question of what a statement

like ‘‘a three percent decrease of GDP’’ really means can create additional confusion.

With that in mind, I would like to start by taking some time to interpret the three

tables in the SPM. Then I would like to make three additional points that are not

emphasized in the summary bullet points but are discussed elsewhere in the SPM

and underlying chapters.

First, the range of estimates should not be interpreted as being a ‘‘likely’’ range—

for the most part, it generally reflects a range of ‘‘best estimates’’ produced in the

literature. Second, there are a couple of reasons why we might want to be cautious

about the low end of the cost estimates. And third, all these estimates assume an

efficient global climate policy; to the extent that actual policies deviate from this

benchmark—which remains useful and quite standard—it is almost certain that

costs will be higher.

I would like to conclude by making a few remarks about how we might use all

of this information to think about our near-term policy choices in the United States.

What does the SPM say about costs?

There are a variety of ways to think about the cost of reducing greenhouse gas

emissions. One is to think about how much we have to pay for each ton being reduced. Another is to think about the impact of making those payments on other

things we care about—like our income, consumption, or well-being. Alternatively, we

251

might ask about effects on employment or energy prices, or about the distribution

of these various impacts on different regions, sectors, or demographic groups.

Most studies of mitigation costs focus on the first two measures—payment for

tons reduced and the impact on income—and do so with relatively little

disaggregation. For that reason, the IPCC similarly focuses on these two measures

in the SPM and the underlying report.

The two tables above, reproduced from the SPM, summarize and synthesize work

completed over the last six years examining how much we would have to pay, per

ton, for different volumes of reductions. The rows categorize opportunities based on

maximum estimated cost. As we move down the table to higher maximum estimated

costs, we see more opportunities, as they necessarily include preceding, cheaper opportunities. The columns then report the volume of reductions available at or below

the per-ton cost indicated in each row, first in actual tons (column 2) and then in

relation to two different estimates of what emissions might otherwise be in 2030

(columns 3 and 4). All estimates reflect calculations for 2030.

Reading the bottom row of Table SPM 2, for example, we find that the literature

published over the last six years indicates between 17 and 26 billion tons of carbon

dioxide—or the carbon dioxide equivalent of other greenhouse gases—is available at

or below $100 per ton.

This kind of data—schedules of emissions reductions and price—are useful for

several reasons. First, these prices on carbon dioxide can be converted relatively

easily into prices on things like electricity and gasoline. One dollar per ton of carbon

dioxide is roughly one penny per gallon of gasoline, one-tenth of a cent per kilowatthour for coal-fired electricity, and one-twentieth of a cent per kilowatt-hour for gasfired electricity. Thus, $20 per ton of carbon dioxide would be an increase of about

20 cents per gallon of gasoline, two cents per kilowatt-hour for coal-fired electricity,

and one cent per kilowatt-hour for gas-fired electricity. Second, this data can be

used to gauge how much harder it is to squeeze out more and more reductions. Note

that going from $20 to $50—a 150 percent increase in price—brings out about 50

percent more reductions. Yet, doubling again to $100 brings out only another 20 percent. Emissions reductions get harder the more you do. Finally, they can be used

to make crude calculations of overall costs, calculations that later can be checked

against estimates from more sophisticated models. The calculation is usually made

as one-half the price times the volume of reductions, where the ‘‘one-half’’ accounts

for the fact that these are maximum prices; many of the reductions would cost less.

Applying that to the bottom row of Table SPM 2, for example, we could estimate

the cost of 26 billion tons of reductions at 1/2 x $100 / ton x 26 billion tons = $1.3

trillion.

While this simple approach is a good starting point for thinking about costs, one

advantage of a top-down model is its ability to internally and consistently add up

costs, to consider the interaction of mitigation policies with other fiscal policies,

trade, and possible market failures, and to consider how costs are spread out over

252

time. Top-down models can also model emissions pathways that stabilize greenhouse gas concentrations in the atmosphere. With that in mind, we turn to Table

SPM 4.

This table shows, along different rows, the estimated cost of stabilization at three

different ranges of concentrations of carbon dioxide and other gases, expressed in

carbon dioxide equivalent. These ranges are given in the first column. Costs in the

second and third column are expressed as a share of global GDP, which is a measure of the income flowing to the world’s inhabitants in the form of wages, capital

income, and the sale of natural resources. That is, it is the fraction of income that

is no longer available for consumption or investment by individuals, firms, or governments, because it is being used to reduce greenhouse gas emissions.

The fourth column indicates the corresponding effect on growth, a measure that

I personally find confusing. Any effect on income, when viewed far enough into the

future, or from far enough in the past, will be a small fraction of annual growth.

To put this into perspective, a policy decision conducted in 1983 concerning a $120

billion cost today—one percent of U.S. GDP—could have been expressed as a 0.05

percent reduction in annual growth (much like the first row of Table SPM 4). Had

we viewed the decision in 1960, however, the effect would be half, a 0.025 percent

reduction in growth. Regardless, the cost is $120 billion or one percent of GDP

today, which is why I tend to focus on columns two and three.

The range of estimated costs summarized in columns two and three is defined by

the range of top-down modeling estimates published over the last six years, excluding the highest and lowest 10 percent of the estimates. In the case of the lowest

range, 445–535 ppm carbon dioxide equivalent, there are too few studies to say anything more than that the estimated costs in all the available studies are below three

percent of GDP.

Three percent of GDP means a three percent loss of income; whether that—

or some other number—is a lot or a little depends on how we view mitigation benefits and other consequences.

Today, three percent of GDP in the United States would mean $360 billion. (For

the world, it would be about five times higher.) These costs are annual, so that

would be $360 billion per year. In terms of households, we could consider the effect

on the median household—that is, the household for which half the population is

wealthier and half the population is poorer. According to the Census Bureau, median income in 2005 was about $46,000. Three percent would then mean a cost of

about $1,380, per year, for the median household. Of course, household income will

be a lot higher in 2030, right? Yes and no. Mean household income has grown at

almost 1.3 percent per year for the past 40 years. However, median household income has only grown at 0.7 percent. Projecting forward at the historic rate suggests

median income would be about $55,000 and three percent would amount to $1,650.

More importantly, whether we believe $1,650 is a lot or a little—or whether we

believe a different number is a lot or a little—to a large extent hinges on what we

think it is worth to mitigate the predicted effects of climate change and by how

much. We return to this issue at the end of my testimony. First, we need to go back

to the numbers and make a few important points.

The range of estimates does not have a likelihood or probability associated

with it.

A somewhat misleading feature of providing a range of estimates, as we see in

Tables SPM 1, 2 and 4, is that it suggests the true outcome will likely fall in that

range, and the question is simply where. This is particularly true in Table SPM 4,

where the range is explicitly referred to as representing a ‘‘10th and 90th percentile

253

range of the analyzed data.’’ A probabilistic interpretation, however, is not right.

The range of estimates, particularly in Tables SPM 2 and 4, reflects the range of

best estimates provided by different experts in the literature. In some cases, the

same model is included with different assumptions, but generally each estimate represents the researchers’ best attempt to estimate future emissions and mitigation

costs. As such, there is relatively little effort to quantify uncertainty in the estimate.

As an analogy, suppose you asked a group of experts to estimate the number of

‘‘heads’’ in 100 coin flips. Most likely, they would all say 50, which is the most likely

outcome, and the ‘‘range’’ of estimates would be exactly 50. However, it is a straightforward statistical exercise to show that there is a one in four chance that the number of heads will exceed 55 or be less than 45. And there is a one in 20 chance that

it will be at least 60 or no more than 40. The range of expert estimates says little

about the actual spread of outcomes. In other words, there is a difference between

a range of best guesses and a range that represents some notion of likely outcomes.

While there are well-established procedures for expert elicitation that generate

ranges with probabilistic interpretations, those procedures have not been applied to

this question of mitigation costs.

There are reasons to be cautious about the low end of the cost estimates

A question that might have arisen in the context of Tables SPM 1 and 2 is why

two separate tables contain what is apparently the same information. Table SPM

1 makes use of a particular kind of study, referred to as ‘‘bottom up.’’ Researchers

itemize different actions or technologies that could be applied to reduce emissions.

They estimate the cost per ton of that action or technology, as well as the volume

of reductions that could be reduced. Adding up the volume of reductions available

at or below different price points yields these bottom-up estimates.

Table SPM 2 summarizes results from an entirely different kind of study, referred

to as ‘‘top down.’’ In these studies, researchers have constructed complete, though

necessarily approximate, models of the global economy that include emissions of

greenhouse gases. These models are designed to replicate the (historically) observed

responsiveness of consumers and businesses to changing prices—including energy

and other activities causing greenhouse gas emissions. These models can be used

to simulate what will happen if the price of greenhouse gases is increased and, in

particular, how emissions of greenhouse gases will be reduced.

Both kinds of approaches have strengths and weaknesses. Bottom-up approaches

can include a wider variety of specific technological options that are often too numerous and detailed to be incorporated in a top-down model. Top-down models,

meanwhile, better represent historical patterns of behavior and responsiveness.

They also enforce accounting consistency—all the flows of goods and services are

tracked and supply must equal demand in every market. Bottom-up analyses are

often tabulations of opportunities that run into difficulties when some opportunities,

like energy efficiency, interact with others, like fuel switching, to create the risk of

double counting. Bottom-up analyses are also not forced to use the same baselines;

indeed, the different sectoral analyses compiled in Table SPM 1 used different baselines, as detailed in the notes to Figure SPM 6.

But the most significant concern about bottom-up analyses, acknowledged in the

definition of ‘‘economic potential’’ given in Box SPM 2, is that they assume the removal of barriers that often prevent or increase the costs of actions being represented. This is especially true for the ‘‘zero-cost’’ opportunities, often energy efficiency projects, highlighted in Table SPM 1. For example, it is often hard to capitalize energy efficiency investments in buildings, making such investments less

profitable for investors who might sell the building. Similarly, increased fuel economy in automobiles may pay for itself—but those same technologies can often be

used to increase power and size, keeping fuel economy unchanged. If consumers put

a higher value on these other characteristics, the proper way to value the cost of

higher fuel economy is not the actual cost of the technology, but the forgone value

to consumers of not having these other characteristics. Regardless of what barrier

is preventing a zero-cost option from being adopted, it is sensible to imagine that

it will not be entirely costless to remove it. Similar concerns arise for the positive

cost opportunities, where the presence of barriers similarly tends to raise costs

above the bottom-up estimates. Whether this concern is an argument for supplemental policies to remove barriers, for higher cost estimates, or for both, is unclear.

It is worth noting that Chapter 11 qualified the bottom-up estimates as having ‘‘medium agreement and medium evidence.’’

Meanwhile, none of this is to say that no zero- or low-cost opportunities exist;

rather, it leads me to put less confidence in the lower end of the bottom-up range

of estimates. It also raises the question of exactly what kinds of policies are going

to be required to remove barriers and to get at these opportunities. Market-based

254

policies that put a price on carbon dioxide emissions are clearly not enough, as the

zero-price opportunities reflect, suggesting the need for direct regulation or other

interventions.

It should be noted that almost by construction, top-down models ignore the possibility of zero-cost mitigation opportunities—as reflected by the absence of a ‘‘$0’’ line

in the Table SPM 2. While viewed as a strength by economists like myself, those

who have greater confidence in the zero-cost opportunities and the possibility of

policies to achieve them, see this as a weakness.

Given these observations about differences between top-down and bottom-up models, it is remarkable that the range of estimates is quite similar across the estimates, as presented in Tables SPM 1 and 2. In the previous, Third Assessment Report (TAR), the top-down estimates tended to show higher costs and lower mitigation potential. Chapter 11 attributes this to two changes in top-down models since

the TAR: inclusion of other greenhouse gases and endogenous technological change,

both of which would be expected to lower costs. Let’s look briefly at how AR4 topdown estimates compare to the TAR.

255

Compared to the TAR, the new AR4 presents a range of estimates with a

similar upper bound, but with a new lower bound including possible economic gains.

Only two pages (section 8.4.3) in the TAR focus on the cost of stabilization comparable to the new AR4 review. Figure 8.19, reproduced from that section above,

shows an average of results from six models for stabilization at 550 ppm carbon dioxide (that is, excluding other gases) and using different baselines. The figure provides a snapshot of reductions and costs in 2050. The horizontal axis indicates the

different volume of reductions required to meet the 550 concentration target, based

on the different baseline emissions scenarios. The vertical axis shows costs as a perVerDate 11-MAY-2000 16:04 May 12, 2008 Jkt 032966 PO 00000 Frm 00029 Fmt 6601 Sfmt 6621 C:\WORKD\FULL07\020807\32966B.TXT SCIENCE1 PsN: SCIENCE1
256

cent of global GDP. The figure suggests costs of between one-tenth of one percent

and almost two percent of global GDP, depending on the baseline.

For comparison, we can examine Figure 3.25(a) in the Fourth Assessment Report.

Unlike the TAR, this figure shows some models independently while the full range

of results, excluding the top and bottom 10 percent, is shaded grey. Here, there is

no attempt to draw out the effect of different baseline emissions assumptions, as

in the previous figure; instead we see the GDP effects along the vertical axis for

different levels of eventual stabilization along the horizontal axis. For comparison

with the TAR review, we focus on the ‘‘category C’’ levels, or about 650 carbon dioxide equivalent (i.e., including the other gases that were excluded in the TAR). What

we see is that the upper end of the range is still around two percent, but now the

lower end includes a net gain of one percent.

What explains this difference? As noted previously, two reasons are given in the

text. One is that the new scenarios include studies with multiple greenhouse gases,

which generally lowers costs because they offer cheaper mitigation opportunities in

percentage terms. While true, it does not explain negative costs—in top-down models, as also noted earlier, negative cost options typically do not exist, even for other

greenhouse gases. Instead, negative costs can arise in models where technological

change is endogenous, a point we now examine in more detail.

Assumptions about technological change can lower costs and even make

them negative-but we should be cautious.

Assumptions about technology have always been viewed as critical to the estimate

of mitigation costs—this was a key observation in the TAR. A new development

since the TAR is use of endogenous technological change (ETC) in some models.

What is endogenous technological change? Most models used to estimate the cost

of mitigation take the process of technological change as given; that is, the availability of new technologies at particular times and at particular costs is one of the

assumptions that researchers plug into their model. An alternative is to have the

model figure out when these technologies become available and at what cost, typically in response to spending on research and increased demand. At first blush, this

makes all the sense in the world: of course, technologies and costs should be responsive to policies and behavior. The problem, of course, lies in the details.

More specifically, the problem is that there is relatively little empirical evidence

about how technological change will respond to increased spending or increased demand for emissions reductions. On the one hand, there is evidence in the literature

on spill-over effects that increased spending on emissions-reducing research will

yield net economic gains because the return to research spending is extremely high.

On the other hand, there is evidence in the literature on crowding out effects that

increased spending emissions-reducing research will come at the expense of other

high-return research, such as health care. How these two competing effects play out

determines the extent to which ETC reduces costs or even produces negative costs.

In yet another modeling arena, we often see the costs of various technologies decline almost naturally with increased use and production—for example, the spectacular decline in the cost of computing power over the past three decades. It is easy

to imagine implying such a relation to the costs of new emission-reducing technologies as experience accumulates. Yet, it is hard to isolate what causes that decline—namely production and use alone, or possibly unmeasured and coincident

spending on research—and to know whether similar declines will occur for other

technologies.

Despite these unresolved empirical questions, researchers have produced a large

volume of work over the past six years in which they have experimented with making the availability and cost of new, emissions-reducing technologies responsive to

additional research and demand. The two figures below, taken from Figure 11.9 in

the underlying Working Group III report, summarize a major synthesis study looking at the consequences of this ‘‘endogenizing’’ of technological change—that is,

making it responsive to additional research and demand. These figures summarize

a collection of results from different models, with the dark colored lines showing

averages across different for each of four scenarios and the light grey lines showing

the spread across different models for one scenario. The first figure, Figure 11.9(a)

shows carbon prices, analogous to those reported in Tables SPM 1 and 2, associated

with two different levels of stabilization, 550 and 450 ppm carbon dioxide, both with

and without endogenous technological change. The second, Figure 11.9(c) shows the

effect on global GDP, similar to Table SPM 4.

The figures are complex, but highlight two important points. The first is seen by

comparing the brown triangles (‘‘450 ppmv without ETC’’) to the red triangles (‘‘450

ppmv with ETC’’). The ‘‘with’’ and ‘‘without’’ ETC refers to whether technology is

allowed to adjust in response to a constraint on carbon dioxide emissions. The obviVerDate 11-MAY-2000 16:04 May 12, 2008 Jkt 032966 PO 00000 Frm 00030 Fmt 6601 Sfmt 6621 C:\WORKD\FULL07\020807\32966B.TXT SCIENCE1 PsN: SCIENCE1
257

ous point is that it makes a huge difference, more than halving the costs in 2030,

whether viewed as the price of carbon dioxide or the loss of GDP. The second point

is that there are widely divergent results across models—the light grey lines show

the individual model results for the ‘‘450 ppmv with ETC’’ case. Some models show

gains, other show losses; even excluding the extremes, the range is from a one percent gain in GDP to a three percent loss in 2030.

My view is that while the estimates holding technology availability and cost fixed

are clearly wrong, we do not have a sufficient understanding of the empirical relationship between research spending, demand for emissions-reducing technology, and

eventual decreases in technology cost to give equal weight to the cost estimates produced by models where technology is endogenous. Both the significantly different estimates across models and the large effect on the central values of switching endogenous technological change on and off make this a very important point. It is precisely these models with endogenous technological change that drive the lower end

of the range of estimates in Tables SPM 2 and 4. Therefore, I tend to be cautious

about the plausibility of these lower-end estimates, especially so for the estimates

suggesting negative costs in Table SPM 4.

The assumption of global least-cost strategies means costs are likely to be

higher.

My last point about the SPM cost estimates, highlighted in Box SPM 3, is that

the estimates in these tables generally assume a global, least-cost strategy. That

means all nations are engaged in market-based policies that put a single price on

emissions reductions in all sectors throughout the world. Deviation from that—for

example, the lack of participation (or least cost participation) of key developing

countries or use of less efficient sectoral policies—will raise costs, according to some

estimates, by a factor of two or more.

258

None of this means ‘‘do nothing;’’ it simply means we need a thoughtful

consideration of costs and benefits.

In summary, Table SPM 4 provides perhaps the simplest relationship between

various long-term environmental goals and the economic impact, in terms of forgone

income, estimated to result in 2030. According to that table, stabilization in the 650

ppmv carbon dioxide equivalent range will cost between -0.6 and 1.2 percent of global income, in the range of 550 ppmv between 0.2 and 2.5 percent, and in the range

of 450 ppmv less than three percent. Alternatively, we could use Tables SPM 1 and

2 to assess the mitigation possibilities at different carbon dioxide prices. My three

observations on these results are that (1) given my indicated concerns about the

low-end estimates in the SPM, my own view about mitigation costs lies at the middle to higher end of the estimated ranges, (2) our uncertainty about costs is not represented by the given range, which is a collection of best estimates, and (3) actual

policy implementations are likely to be more expensive than the indicated range because the global, least-cost benchmark is at best an ideal.

Given my view of these cost estimates—that our best guess is somewhere from

a few tenths of a percent of GDP up to three percent, depending on the stabilization

target—how do we choose a course of action, especially in the near-term? Here I

would offer five possible suggestions.

First, consider what these concentration targets will do to the environment. A colleague of mine, Richard Newell, put together the figure below relating concentration

targets to the likelihood of different changes in temperature. Across the horizontal

axis are various concentration goals; the vertical axis shows the range of likely temperature increases. Combined with the Figure SPM 1 from Working Group II, reproduced at the end of this document that shows the impacts associated with different

levels of warming, we could make decisions about how much we are willing to pay,

in terms reduced GDP based on Table SPM 4, to reduce the risk of various outcomes.

Second, consider what cost-benefit analysis suggests. Recent work by William

Nordhaus has suggested that near-term benefits of reducing carbon dioxide emissions are about $7 per ton of carbon dioxide. These estimates are very sensitive to

assumptions about future interest rates and/or how to value consequences over long

periods of time. My own work with colleague Richard Newell on uncertainty and discounting suggests roughly doubling his estimates to about $15 per ton of carbon dioxide.

Third, consider practical near-term constraints. Earlier, I mentioned the effect of

carbon dioxide prices on gasoline and electricity prices. One limit to efficient market-based approaches that put a price on carbon dioxide is consumers’ willingness

to pay higher energy costs. If $15 per ton of carbon dioxide implies 15 cents per galVerDate 11-MAY-2000 16:04 May 12, 2008 Jkt 032966 PO 00000 Frm 00032 Fmt 6601 Sfmt 6621 C:\WORKD\FULL07\020807\32966B.TXT SCIENCE1 PsN: SCIENCE1
259

lon and something slightly less than 1 cent per kilowatt-hour, that is useful information for calibrating a domestic policy. Another useful benchmark is the effect on

coal use. For a variety of reasons—energy security, regional economic interests,

pressure on natural gas prices—the effect on coal use is a useful metric. According

to the Energy Information Administration, a price of $15 per ton of carbon dioxide

in 2020 implies relatively constant coal use compared to current levels.

Fourth, look at what other countries are doing. The price in the EU Emissions

Trading Scheme, the only significant carbon dioxide emissions trading program in

the world, has fluctuated between $12 and $35 per ton and is currently around $25.

These prices give some estimate of what is possible without appreciable dislocation.

Finally, recognize that the most significant lesson in this exercise is the role of

technology and technological change. Addressing climate change is not just about

picking an emissions target or a price—unquestionably an important part. It is also

about designing a suite of policies that support technology development and deployment over time.

I thank you again for the opportunity to appear before this committee, and I

would be pleased to answer any questions.

BIOGRAPHY FOR WILLIAM A. PIZER

Billy Pizer is a Senior Fellow at Resources for the Future where his research

looks at how the design of environmental policy affects costs and environmental effectiveness, often related to global climate change. His research has examined the

aggregate level and distribution of regulatory costs, the effect of uncertainty on policy outcomes, the choice among various market-based policies, the role of voluntary

programs, impacts on competitiveness, the importance of technological change, and

the valuation of environmental benefits over long time horizons.

Pizer was a Lead Author on the Intergovernmental Panel on Climate Change 4th

Assessment Report, chaired the DOE review of its Integrated Assessment Research

Program, and serves on both the EPA Environmental Economics Advisory Committee and the DOE Climate Change Science Program Product Development Advisory Committee. Since August 2002, Pizer has worked part-time as a Senior Economist at the National Commission on Energy Policy. During 2001–2002, he served

260

as a Senior Economist at the President’s Council of Economic Advisers where he

worked on environment and climate change issues. He was a Visiting Scholar at

Stanford University’s Center for Environmental Science and Policy during 2000–

2001, and taught part-time at Johns Hopkins University during 1997–1999. His

work has been published in the Review of Economics and Statistics, Journal of Public Economics, Journal of Environmental Economics and Management, as well as

other scholarly journals and books. In 2006 he won, with Richard Newell, the Petry

Prize for their work on discounting.

STATEMENT OF MR. STEVEN E. PLOTKIN, TRANSPORTATION

ENERGY ANALYST WITH THE CENTER OF TRANSPORTATION

RESEARCH AT THE ARGONNE NATIONAL LABORATORY

Mr. PLOTKIN. Mr. Chairman and Members of the Committee,

thank you for this opportunity to discuss the IPCC’s finding on

mitigating greenhouse gas emissions from the transport sector.

Transport is especially important because it represents nearly a

quarter of energy-related greenhouse emissions, because is it growing rapidly, and because it is bound so tightly with oil. Oil supplies

95 percent of its fuel, and transport represents half of world oil use

and about two-thirds of U.S. oil use.

On their currently path world transport emissions and oil use

will grow at about two percent per year. That means that by 2030,

they will have grown by 80 percent, almost doubling. Although

much of that growth will occur in the developing world led by

China, U.S. transport emissions and oil use are also expected to

grow at nearly two percent per year.

If conventional oil production cannot keep pace with this rapid

growth, the most likely supplemental fuels would be liquid fuels

from tar sands, heavy oil, coal, and natural gas. These supplements

would tend to increase greenhouse emissions.

Further, a transition to these fuels would probably not go

smoothly and supply disruptions and very high prices would be

likely. This creates a strong added incentive to take steps to reduce

the growth rate of transport’s oil use.

Much of the growth in transport emissions is driven by the rapid

increase in ownership of personal vehicles, including two-wheel vehicles in the developing world. Although much attention is focused

on this growth, both freight transport and air transport deserve

close attention also. Freight now counts for over one-third of transport energy use and greenhouse emissions and actually is growing

more rapidly than passenger transport. And air travel accounts for

12 percent of emissions. It has got a five percent growth rate,

which is the fastest of all modes, and its effects on climate change

are magnified by airplane contrails and the cirrus cloud enhancement caused by the high altitude of aircraft emissions.

Since the IPCC’s third assessment report in 2001, there have

been significant advances in efficiency technology. Direct injection

diesel engines, 30 percent more efficient than gasoline engines,

have over 50 percent of new car sales in Europe. These engines are

much cleaner than older diesels, and their emissions performance

continues to improve.

Automakers also have made great strides in improving the performance and reducing the costs of hybrid electric vehicles, and

their use is spreading. Their ultimate role, however, will depend on

how successful automakers are at further reducing their costs.

261

Finally, there has been steady progress in hydrogen fuel cell development. But further progress in reducing costs, and increasing

onboard hydrogen storage capability, and strong Government support is crucial to future commercialization.

Several potential improvements to new light-duty passenger vehicles, that is cars and light trucks, conceivably double their fuel

economy by 2030. These are briefly described in my written testimony, and let me give you an idea of the costs. We are talking

about costs that are comparable to leather seats and a sunroof or

four-wheel drive. A few thousand dollars. The key issue is whether

these technologies will be used for reducing fuel consumption or instead to increase performance and size. EPA estimates that increased weight and acceleration capability has cost the U.S. new

car and light truck fleets’ fuel economy over five miles per gallon

between 1987, and 2005. That is, we can use this technology for

fuel economy, or we can use this technology for other things. And

although the U.S. may be an extreme case, this type of tradeoff of

performance and size versus fuel economy is being made throughout the world.

Technologies exist to reduce greenhouse gasses in other transport

areas as well. For example, a combination of aerodynamic and engine improvements could increase the fuel economy of intercity

freight trucks by as much as 50 percent when they are on the highway. And biofuels can play a substantial role in reducing greenhouse gas emissions from all transport modes. Displacing as much

as a quarter of oil-based fuels by 2050, but only if we make substantial progress in developing the technology for using materials

such as switchgrass and wood waste.

There is an array of potential policy tools to help reduce transport greenhouse emissions. In the areas with rapid urbanization

and transport systems in the early stages of development, good

urban design, development of efficient public transport systems,

and promotion of walking and biking can reduce the number and

use of personal vehicles while providing excellent mobility and access to services. These policies also have an important role to play

in the United States and elsewhere in the industrial world, although obviously much of the die is cast in terms of our dependence on personal vehicles and in the form of our urban areas.

Another key policy tool is from, to reduce greenhouse gas emissions from personal vehicles is the fuel economy standard. Standards are now being widely used, even in countries with much higher fuel prices and vehicle taxes than ours. They have been effective

in the past in the United States and elsewhere in slowing the

growth of oil use and greenhouse emissions. Some form of fuel

economy or CO2 standard or agreement is now in place in Japan,

the European Union, China, Australia, and elsewhere. And the

State of California and a group of other states are attempting to

establish their own CO2 standards.

Taxation policies on fuels and vehicles can also play an important role. Some of these policies may translate into a fairly high

gasoline tax, however, we can recycle those taxes, we can reduce

taxes elsewhere in the economy. If we do that intelligently, the effect on the economy does not have to be negative. Many countries

262

do have a lead tax motor fuels and have lower rates of fuel consumption than countries like ours with low taxes.

However, vehicle travel demand, the demand for vehicles and

fuel use are not highly price elastic, so relatively high taxes are required to have major effects on fuel use and greenhouse gas emissions.

For the longer-term there are a number of technologies that can

make a major difference in transport emissions but all require significant advances that must be addressed by strong research and

development programs. And here governments can play a significant role. Some promising examples are radical improvements in

conventional gasoline engines, light-weight materials for vehicles,

advanced biofuels from cellulosic materials, hydrogen fuel cell vehicles, plug-in hybrids, blended wind aircraft bodies, and unducted

turbo fan engines, and advanced diesel engines for freight trucks.

Mr. Chairman, this concludes my testimony, and I will be delighted to answer any questions.

[The prepared statement of Mr. Plotkin follows:]

PREPARED STATEMENT OF STEVEN E. PLOTKIN

FINDINGS OF THE TRANSPORTATION SECTOR

ANALYSIS

Mr. Chairman and Members of the Committee, thank you for this opportunity to

discuss the findings of the Intergovernmental Panel on Climate Change (IPCC) on

mitigating greenhouse gas (GHG) emissions from the transport sector. I draw extensively in this testimony from Chapter 5 of the full report, of which I was a co-author.

SUMMARY

The transport sector is an especially important focus of policy concern because it

represents nearly a quarter of energy-related greenhouse gas (GHG) emissions and

is growing rapidly, and because it is bound so tightly with oil—oil supplies 95 percent of its fuel, and transport represents half of world oil use (and about two-thirds

of U.S. oil use).

Technologies are available today to sharply reduce the growth of oil use and GHG

emissions from transport, but strong government actions will be needed for these

technologies to reach their full potential. Useful policies include fuel economy standards, registration and annual fees on vehicles tied to efficiency, public support for

transit and urban planning, and a host of others.

For the longer-term, there are a number of technologies that could make a major

difference in transport emissions, but all of these require significant advances that

must be addressed by strong research and development programs. Some promising

examples are radical improvements in conventional gasoline engines; lightweight

materials for vehicle structures; advanced biofuels from cellulosic materials; hydrogen fuel cell vehicles; plug-in hybrids; blended-wing aircraft bodies and unducted

turbofan engines; and advanced diesel engines for freight trucks.

A combination of careful urban planning and promotion of efficient public transport and walking and cycling can have a profound longer-term positive impact on

GHG emissions from urban transport as well as on the livability of cities. Although

the greatest impacts will be in the developing world whose cities and transport systems are undergoing rapid transformation, important positive impacts can occur in

the industrialized nations as well.

DETAILED TESTIMONY

Transportation accounts for about 23 percent of the world’s energy-related GHG

emissions, and is the fastest growing end-use sector. Three quarters of its emissions

come from road vehicles. If transport energy use and GHG emissions continue on

their current path, world transport emissions will grow at about two percent per

year; by 2030 they will have grown by 80 percent. Much of that growth will occur

in the developing world—the nations outside of the OECD account for 36 percent

of emissions today, but are expected to account for 46 percent by 2030, with nations

263

like China leading the way with its astonishing 20 percent/year growth in private

vehicle ownership. However, the United States is expected to have transport growth

not much lower than the world average during this period.

Much of the growth of transport is driven by rapid increases in the ownership of

personal vehicles—including two-wheeled scooters and motorcycles as well as passenger cars. As personal wealth has grown in developing nations, the motorized personal vehicle is being seen as a status symbol as well as a means to faster, more

flexible and convenient, and more comfortable travel than public transport. In this

part of the world, development of excellent public transport systems and intelligent

shaping of urban growth will be crucial to future GHG emissions as well as to adequate access of urban populations to jobs, recreation, and other services.

Although most attention in transportation has been paid to personal travel,

freight transport now accounts for over a third of transport energy use and GHG

emissions, and is growing more rapidly than passenger transport. Freight operations are driven more strongly than personal travel by energy costs, but pressure

to increase speed and reliability and provide smaller ‘‘just-in-time’’ shipments means

that there has been an ongoing movement to faster and more energy-intensive

modes.

Air travel, most of it for personal travel, is also a crucial sector—currently it accounts for about 12 percent of transport GHG emissions, it is growing the fastest

of all modes (five percent/year), and its effects on climate change are magnified by

contrails and on cirrus cloud enhancement caused by the high altitude of aircraft

emissions.

The importance of the transport sector’s energy use and GHG emissions is magnified by the fact that transportation and oil are inextricably linked. . .worldwide,

oil supplies about 95 percent of transport energy, and the ratio is similar in the

United States—and transport accounts for about 50 percent of worldwide oil use, a

share that will grow over time (for the U.S., transport’s share is about two thirds).

There is now a debate about the likelihood that conventional oil production may be

nearing its peak, which could have drastic consequences for both energy security

and GHG emissions. If conventional oil production cannot keep pace with transport

demand growth, the most likely fuels to supplement oil-based fuels would be liquid

fuels from unconventional fossil resources—tar sands, heavy oil, and coal—and liquids synthesized from natural gas. These supplements would tend to increase GHG

emissions. In my personal view, it is quite likely that the transition to such fuels

would not go smoothly, and supply disruptions and very high prices would be probable. Further, even if oil resource optimists prove to be correct, expanding production to match demand will require huge investments in oil-producing regions with

troubled investment environments. If these investments are not forthcoming, future

supply problems will be severe. These issues create a strong added incentive to focus

on reducing the growth rate of demand for oil.

Efficiency Technology

Improvement in energy efficiency is a key method of reducing GHG emissions.

Since the Third Assessment Report (TAR) in 2001, there have been significant advances in efficiency technology. For example:

• Turbocharged direct injection diesel engines, capable of improving fuel efficiency by 30 percent or more over similar gasoline engines, have attained a

market share of over 50 percent of new car sales in Europe. These engines

are much cleaner than the last generation of diesels, and their emissions performance continues to improve.

• Hybrid-electric vehicles had just been introduced at the TAR’s publication;

since the TAR, automakers have made great strides in improving their performance and reducing their costs, and their use has spread to bus fleets and

recently to urban trucks. They clearly will play a larger role in the future,

but the extent of their penetration into the road vehicle fleet depends strongly

on further reducing their costs.

• There has been steady progress in hydrogen fuel cell development, especially

in reducing the cost, size and weight of fuel cell systems; however, further

progress in reducing costs and increasing on-board hydrogen storage capability is crucial to future commercialization—and hydrogen is likely to play

a significant role only with strong government support.

An array of potential improvements to new light-duty passenger vehicles conceivably could double their fuel economy by 2030. Aside from hybrid drivetrains, there

can be substantial improvements in both gasoline and diesel engine technology,

weight reduction through lightweight materials and improved designs, better aerodynamics and tires, improved transmissions, and so forth. However, a key issue will

264

be the extent to which these technologies are used for reducing fuel consumption

or instead to obtain other things—larger vehicles; better acceleration performance;

more amenities such as four-wheel drive; and improved safety. The U.S. Environmental Protection Agency has estimated that the U.S. new car and light truck fleet’s

fuel economy in 2005 would have been 24 percent higher had the fleet remained at

the weight and performance distribution it had in 1987. Instead, it became 27 percent heavier and 30 percent faster in 0–60 mph acceleration time—and fuel economy

actually declined a bit. Although the U.S. may be an extreme case, this type of

tradeoff of performance and size versus fuel economy is being made to some degree

throughout the world.

A wide array of technologies exists to reduce GHG emissions in other transport

areas. For example, an array of body shaping and other measures on inter-city

freight trucks can sharply reduce aerodynamic drag; coupled with significant improvements in diesel technology, fuel economy improvements as high as 50 percent

may be possible for high speed operation. Similarly, substantial improvements in efficiency are possible for trains and airplanes.

Biofuels can play a substantial role in reducing GHG emissions from all transport

modes. A recent International Energy Agency study estimated that biofuels could

substitute for 4–7 percent of transport fuel in 2030 and 13–25 percent by 2050 at

costs less than U.S.$25/metric ton of CO2. However, the higher values require substantial progress in developing the technology for using cellulosic materials (such as

switchgrass and wood waste) as fuel feedstocks.

Policy

There is an array of potential policy tools that could help to reduce GHG emission

growth throughout the transport sector. As noted above, in areas with rapid urbanization and transport systems in the early stage of development, good urban design,

development of efficient public transport systems, and promotion of walking and

biking can reduce the growth of personal vehicles while providing excellent mobility

and access to services. These policies also have an important role to play in the

United States and elsewhere in the industrialized world, although much of the die

is cast in terms of dependence on personal vehicles and in the form of urban areas.

A key policy tool that is applicable worldwide is the fuel economy standard for

personal vehicles. Such standards are now widely used, even in countries with much

higher fuel prices and vehicle taxes than ours, and much better public transport systems. These have been effective in slowing the growth of oil use and GHG emissions, and they were effective in the United States—in consort with higher fuel

prices—in raising new light-duty vehicle fuel economy from 13.1 mpg in 1975 to 22.1

mpg in 1987. Some form of fuel economy or CO2 standard or agreement is now in

place in Japan, the European Union, China, Australia, and elsewhere, and the State

of California and a group of other States are attempting to establish their own CO2

standards. In my personal view, the new attribute-based standard for light trucks

recently established by the National Highway Traffic Safety Administration, based

on a vehicle’s ‘‘footprint’’ (wheelbase times track width) is worthy of close attention

as a candidate for a standard for the combined fleet of cars and light trucks.

Taxation policies on fuel and vehicles can also play an important role. Many countries do heavily tax motor fuels and have lower rates of fuel consumption than countries with low taxes. However, vehicle travel demand, the demand for vehicles, and

fuel use are not highly price elastic, so relatively high taxes are required to have

major effects on fuel use and GHG emissions. A variety of transportation demand

management (TDM) strategies can also reduce the use of personal vehicles and reduce GHG emissions.

Several of the ‘‘high potential’’ technologies that could allow sharp reductions in

GHG emissions from transport will require substantial additional development, so

government support of research and development activities aimed at these technologies is an important policy tool. Key technology areas include:

• Cellulosic biomass—production and sustainability

• Batteries for hybrids, plug-in hybrids and electric vehicles

• Aircraft engines and high efficiency aircraft structures (e.g., the blended wing

concept)

• Hydrogen fuel cells

• Vehicle structural materials

• Advanced gasoline and diesel engines

265

Mitigation Potential

The IPCC estimates that the mitigation potential for the transport sector is about

1,600–2,550 million metric tons of CO2 at carbon prices below $100/ton of CO2. This

estimate does not consider heavy-duty freight and transit vehicles, rail transport,

shipping, and shifts from private vehicles to public transport and non-motorized

travel. The estimate is highly uncertain, however, because of the limited number of

studies of world transport mitigation potential and strong uncertainties about future

oil prices and future progress in technology development. Key areas of uncertainty

are biomass fuel production technology and biomass production sustainability in

massive scale, and battery cost, lifetime, and energy storage capacity.

BIOGRAPHY FOR STEVEN E. PLOTKIN

Steve Plotkin is a staff scientist with Argonne National Laboratory’s Center for

Transportation Research, specializing in analysis of transportation energy efficiency.

He has worked extensively on automobile fuel economy technology and policy as a

consultant to the Department of Energy, and was a consultant to the National Research Council’s study on the Effectiveness and Impact of Corporate Average Fuel

Economy (CAFE) Standards. He is a lead author on the Intergovernmental Panel

on Climate Change (IPCC) 2007 Assessment Report on Mitigating Climate Change.

He was for 17 years a Senior Analyst and Senior Associate with the Energy Program of the Congressional Office of Technology Assessment (OTA) and prior to that

he was an environmental engineer with the U.S. Environmental Protection Agency.

Mr. Plotkin has a BS degree in Civil Engineering from Columbia University, and

a Master of Engineering (Aerospace) degree from Cornell University. He is the 2005

recipient of the Society of Automotive Engineers’ Barry D. McNutt Ward for Excellence in Automotive Policy Analysis.

Chairman GORDON. Thank you, Mr. Plotkin. You gave us a lot

to think about there.

And Dr. Pielke.

STATEMENT OF DR. ROGER A. PIELKE, JR., PROFESSOR OF

ENVIRONMENTAL STUDIES PROGRAM AT THE UNIVERSITY

OF COLORADO AND DIRECTOR OF THE CENTER FOR

SCIENCE AND TECHNOLOGICAL POLICY RESEARCH

Dr. PIELKE. I thank the Chairman the Committee for the opportunity to offer testimony this morning. I just want to note before

I get into my testimony that it was 16 years ago this week I

walked into Rayburn 2320 as a graduate student intern under Congressman George Brown, and I have a great deal of appreciation

for the work that everyone does here, particularly the staff and

how important they are.

My testimony today is based entirely on the information provided

in the Summaries for Policy-makers of Working Groups II and II

of the IPCC. I begin with three assertions.

Number 1. Current debate over climate change represents a

great opportunity to discuss what kind of future will result from

our current decision.

Number 2. Working Group III indicates that the benefits of mitigation outweigh its costs, and based on this conclusion, mitigation

should be a policy priority.

Number 3. Working Group II is concerned with one of the many

pressing challenges to global well-being and emphasizes that greenhouse gas mitigation is only one of many avenues for confronting

these challenges.

The problem that I am addressing today is that we may successfully meet the challenge of greenhouse gas mitigation but still fail

in the broader effort to promote a sustainable future for our

globalizing society.

266

In my written testimony I argue that effective progress on coping

with climate impacts such as sea level rise, tropical diseases, and

disaster impacts, requires a broad focus on sustainable development, including future development in the United States and other

developed countries. I want to emphasize that nothing in this testimony or in any of my work on climate change over the past decade

or more should be interpreted as being opposed to or somehow contrary to the mitigation of greenhouse gases. The main point is that

a focus on control of carbon dioxide cannot substitute for a broader

discussion of policies that will enable the most desirable futures.

And, indeed, this is one of the main messages of the IPCC, which

is discussed in its Working Group II report, but which seems to be

overlooked in the broader debate on climate change. Today I want

to make sure that this message is clear.

The IPCC bases its work on four families of scenarios for the future, which it creatively named A1, A2, B1, and B2. The scenarios

provide a basis for projecting our greenhouse gas emissions growth

in the future as input to climate models, which use the projected

future emissions as an input. The IPCC scenarios are thus alternative visions of how the future might evolve. The IPCC makes no

claim about the relative probability of each scenario actually occurring.

In reality, of course, how the future evolves is the result of decisions that we make. In other words, by making decisions we make

some futures more likely and some futures less likely.

Scenarios are also important because they allow for an analysis

of the importance of decisions that lead to one scenario being realized versus another. A collection of decisions that lead to the realization of a particular scenario is a development pathway. Another

way to think about this concept is as a broad notion of what is traditionally called adaptation.

Now, the essential message of my testimony can be seen in two

figures, and if I could have the first figure put up.

267

This figure shows the IPCC assumptions for global GDP growth.

So you see with that gray bar there the IPCC starts with $20 trillion in 1990. Now, the IPCC, one of its scenarios, its lowest scenario, after you factor in the cost of damage from climate change,

has the green bar showing future global GDP. So it anticipates that

even with damage related to climate change we will be much

wealthier. Under the IPCC assumptions, if we aggressively mitigate, we will be richer. That is represented by the red marginal addition.

268

Now, if we look at another other IPCC scenarios, the one with

the highest global GDP, that is this green bar on the far right, and

indeed, under this scenario there is also benefits to aggressive mitigation. What I would like to emphasize is the difference between

these two development pathways, these two scenarios, which is

shown in this following graph. If you look at the subset, the little

269

yellow box on the lower right there, the green bar represents the

difference in global GDP based on pursuing one development pathway versus another. The red bar, the smaller red bar, represents

the benefits of mitigation, and the point I want to make is that discussions of development pathways are far more important than discussions of mitigation. It is not a substitute for discussions of mitigation, but mitigation has to take place in this broader context.

The conclusions to take from this analysis are as follows. Number 1, mitigation provides benefits under all scenarios I discuss in

my testimony and almost all scenarios presented by the IPCC.

Number 2, in all scenarios discussed here under the assumptions, conclusions, and metrics of value used by the IPCC, the importance of the development path far exceeds the importance of

mitigation. Consequently, a focus on sustainable development

should be central to any discussion of climate polices.

Adaptation provides the link between sustainable development

and climate change by ensuring that the capacity of societies to develop is not compromised by the impacts of climate on their socioeconomic prospects.

Policy discussions about what sort of future we collectively wish

to see unfold are myopic if focused only on greenhouse gas emissions. It would be the equivalent of a family discussion of their future focused only on their utility bill, ignoring their healthcare,

education, housing, and everything else that matters.

It is true, of course, that a family that does not focus on its utility bill may find themselves in deep trouble. So a focus on the utility bill is indeed important, but that cannot be the entire focus.

With respect to the current political debate about the world’s future focused on energy policies, the analysis presented in my testimony based on the assumptions of the IPCC indicates that our

focus needs to be much broader, on the path of development itself.

The most immediate way that the U.S. Congress can influence

sustainable development as related to climate change would be to

focus as intensively on the issue of adaptation as it has in recent

months on mitigation. The Science Committee in particular can

contribute to this agenda by ensuring that the Nation’s climate research portfolio is organized in such a way so as to reflect the information needs of decision-makers facing choices about adaptation.

For example, legislation proposed by Congressman Mark Udall and

others on this committee, is notable for its efforts to more closely

connect climate research with the needs of decision-makers.

In closing, the IPCC has great potential to serve as a unique resource for decision-makers. In my opinion, it will best reach that

full potential not by replicating the important work of advocacy

groups that seek to reduce the scope of choice available to decisionmakers. Instead, the IPCC should serve to empower decision-makers by expanding their view and their options and to clearly distinguish the role of advisor from advocate and advisor from decisionmaker.

Thank you very much.

[The prepared statement of Dr. Pielke follows:]

270

1 At the University of Colorado I am affiliated with CIRES, the Cooperative Institute for Research in Environmental Sciences, a joint institute of the University of Colorado and the National Oceanic and Atmospheric Administration (NOAA). The Center that I direct at CIRES has

received research funding from a number of other federal research agencies, including NSF and

NASA. I thank a number of colleagues who offered perspectives on early versions of this testimony. The views presented here are my own. 2 I discuss this challenge in this testimony: Pielke, Jr., R.A., 2006. Statement to the Committee on Government Reform of the United States House of Representatives, Hearing on Climate Change: Understanding the Degree of the Problem, 20 July. http://

sciencepolicy.colorado.edu/admin/publication¥files/resource-2466-2006.09.pdf 3On this point see especially Chapter 20 of the forthcoming full AR4 WG II report.

4Pielke, Jr., R.A., Prins, G., Rayner, S. and Sarewitz, D., 2007. Lifting the taboo on adaptation. Nature, 445, 597–598. http://sciencepolicy.colorado.edu/admin/publication¥files/resource2506-2007.11.pdf See this paper for citations to the literature.

PREPARED STATEMENT OF ROGER A. PIELKE, JR.

Introduction

I thank the Chairman and the Committee for the opportunity to offer testimony

this morning on ‘‘The State of Climate Change Science 2007: The Findings of the

Fourth Assessment Report by the Intergovernmental Panel on Climate Change

(IPCC), Working Group III: Mitigation of Climate Change.’’ I am a Professor of Environmental Studies at the University of Colorado and also Director of the University’s Center for Science and Technology Policy Research.1 My research focuses on

the connections of science and decision-making. I also have been studying climate

change science and policy for about 15 years. A short biography can be found at the

end of my written testimony, including links to my publications. I am the author

of a recently released book, The Honest Broker: Making Sense of Science in Policy

and Politics (Cambridge University Press, 2007).

On a personal note it is a pleasure to appear before the Science and Technology

Committee. In 1991 I had the opportunity to serve as an intern for the Committee

under Chairman George Brown (D–CA) (and his staff director, Radford Byerly) and

the experience greatly shaped my thinking and has influenced my career ever since.

Three Assertions

My testimony today is based entirely on the information provided in the Summaries for Policy-Makers (SPMs) of Working Groups (WGs) II and III of the Intergovernmental Panel on Climate Change (IPCC). My testimony today begins with

three assertions:

• Current debate over climate change represents a great opportunity to discuss

what kind of future will result from our current decisions. This opportunity

is often missed because of a focus on the negative aspects of climate change

or because debate degenerates into unhelpful partisan or ideological attacks.

• The IPCC WG III indicates that the benefits of mitigation outweigh its costs,

and based on this conclusion, mitigation should be a policy priority. Of course,

the exact details of mitigation policies, and in particular the time symmetry

between costs and benefits, are not trivial.2

• The IPCC WG II is concerned with one of many pressing challenges to global

well-being, and emphasizes greenhouse gas mitigation is only one of many

avenues for confronting those challenges.3 However, this important message

often goes unappreciated in policy debates. We need to make certain that the

focus on the issue of greenhouse gas emissions does not crowd out other important challenges.

What Is the Problem?

The problem is that we can successfully meet the challenge of greenhouse gas

mitigation but still fail in the broader effort to promote a sustainable future for our

globalizing society. In a commentary in Nature, Gwyn Prins, Steve Rayner, Dan

Sarewitz and I argued that mitigation alone cannot solve many of the world’s most

pressing environmental problems, including many that are related to climate:4

For example, in the Philippines, policy-makers have begun to acknowledge the

flood threats posed by the gradual sea-level rise of one to three millimeters per

year, projected to occur with climate change. At the same time, they remain oblivious to, or ignore, the main reason for increasing flood risk: excessive groundwater extraction, which is lowering the land surface by several centimeters to

more than a decimeter per year.

271

5Pielke, Jr., R.A., 2007 (accepted). Future Economic Damage from Tropical Cyclones: Sensitivities to Societal and Climate Changes, Proceedings of the Philosophical Transactions of the

Royal Society. http://sciencepolicy.colorado.edu/admin/publication¥files/resource-2517-

2007.14.pdf

Similarly, non-climate factors are by far the most important drivers of increased

risk to tropical disease. For instance, one study found that without taking into

account climate change, the global population at risk from malaria would increase by 100 percent by 2080, whereas the effect of climate change would increase the risk of malaria by at most seven percent. Yet tropical disease risk

is repeatedly invoked by climate-mitigation advocates as a key reason to curb

emissions. In a world where political attention is limited, such distortions reinforce the current neglect of adaptation.

In another example, the threat of hurricane damages is often invoked in the climate debate as a justification for action on energy policies (e.g., see Figure 1 below),

creating an expectation that future damages can somehow be effectively modulated

according to atmospheric greenhouse gas concentrations. This is simply wrong. In

a forthcoming paper I conclude:5

. . .under a wide range of assumptions about future growth in wealth and population, and about the effects of human-caused climate change, in every case

there is far greater potential to affect future losses by focusing attention on the

societal conditions that generate vulnerability to losses. Efforts to modulate

tropical cyclone intensities through climate stabilization policies have extremely

limited potential to reduce future losses. This conclusion is robust across assumptions, even unrealistic assumptions about the timing and magnitude of

emissions reductions policies on tropical cyclone behavior. The importance of the

societal factors increases with the time horizon.

This does not mean that climate stabilization policies do not make sense or that

policy-makers should ignore influences of human-caused climate change on tropical cyclone behavior. It does mean that efforts to justify emissions reductions

based on future tropical cyclone damages are misleading at best, given that

available alternatives have far greater potential to achieve reductions in damage. The most effective policies in the face of tropical cyclones have been and

will continue to be adaptive in nature, and thus should play a prominent role

in any comprehensive approach to climate policy.

The lesson from these three examples is that effective progress on coping with sea

level rise, tropical diseases, and disaster impacts requires a broad focus on sustainable development. I wish to emphasize that nothing in this testimony—or in any

of my work on climate change over the past decade or more—should be interpreted

as being opposed to or somehow contrary to the mitigation of greenhouse gases. The

main point is that a focus of control of carbon dioxide cannot substitute for a broader discussion of policies that will enable the most desirable futures. And this is inVerDate 11-MAY-2000 16:04 May 12, 2008 Jkt 032966 PO 00000 Frm 00045 Fmt 6601 Sfmt 6621 C:\WORKD\FULL07\020807\32966B.TXT SCIENCE1 PsN: SCIENCE1
272

6http://www.grida.no/climate/ipcc/emission

7http://www.grida.no/climate/ipcc/emission/025.htm

deed one of the main messages of the IPCC, which is discussed in its Working

Group II report, but which seems to be overlooked in the broader debate on climate

change. Today I want to make sure that this message is clear.

Which Path to the Future?

The IPCC bases its work on four families of scenarios for future which are named

A1, A2, B1, and B2.6 The scenarios provide a basis for projecting how greenhouse

gas emissions might grow into the future as input to climate models which use the

projected future emissions as a key input. Figure 2 (below) illustrates the four scenarios as presented by the IPCC with respect to two dimensions.

But the scenarios are much more than projections of emissions. The IPCC describes them as follows:

Scenarios are images of the future, or alternative futures. They are neither predictions nor forecasts. Rather, each scenario is one alternative image of how the

future might unfold. A set of scenarios assists in the understanding of possible

future developments of complex systems. Some systems, those that are well understood and for which complete information is available, can be modeled with

some certainty, as is frequently the case in the physical sciences, and their future states predicted. However, many physical and social systems are poorly understood, and information on the relevant variables is so incomplete that they

can be appreciated only through intuition and are best communicated by images

and stories. Prediction is not possible in such cases.7

The IPCC scenarios are thus alternative visions about how the future might

evolve. The IPCC makes no claim about the relative probability of each scenario actually occurring.

The SRES scenarios are descriptive and should not be construed as desirable

or undesirable in their own right. They are built as descriptions of possible,

rather than preferred, developments. They represent pertinent, plausible, alterVerDate 11-MAY-2000 16:04 May 12, 2008 Jkt 032966 PO 00000 Frm 00046 Fmt 6601 Sfmt 6621 C:\WORKD\FULL07\020807\32966B.TXT SCIENCE1 PsN: SCIENCE1
273

8http://www.grida.no/climate/ipcc/emission/025.htm

9http://www.grida.no/climate/ipcc/emission/057.htm

native futures. . .. Good scenarios are challenging and court controversy, since

not everybody is comfortable with every scenario, but used intelligently they

allow policies and strategies to be designed in a more robust way.8

In reality, of course, how the future evolves is a result of decisions that we make.

In other words, by making decisions we make some futures more likely and others

less likely.

Both IPCC WGs II and III included a short description of the four families of scenarios. The text box on the following page reproduces the summary descriptions of

the scenarios from WG III.

The scenarios are important because they allow for a sensitivity analysis of the

importance of decisions that lead to one scenario being realized versus another. The

collection of decisions that lead to the realization of a particular scenario is a ‘‘development pathway.’’ Another way to think about this concept is as a broad conception

of what is traditionally called ‘‘adaptation.’’

Development Pathways Matter a Great Deal for Societal Outcomes

There are multiple measures that can be used to measure the relative worth of

a particular societal outcome. The SPMs of IPCC WGs II and III emphasize wealth

as measured by global Gross Domestic Product (GDP). So that is the measure used

here. The IPCC justifies its use of this metric in one its chapters in its SRES report

on as follows:

Income is not an end in itself, but a way to enable human choices, or to foreclose them in the case of poverty. Therefore, levels of per capita income (GDP

or GNP) have been widely used as a measure of the degree of economic development, as in many instances such levels correlate closely (as lead or lag indicator) with other indicators and dimensions of social development, such as mortality, nutrition, and access to basic services, etc. Average income values also

do not indicate the distribution of income, which is an important quantity. Composite measures, such as the UN Human Development Index, are also used in

historical analyses (see Box 3–1). Note, however, that the overall nature of scenario results may not vary much even if some other measure could be used, because often-used components, such as literacy rates, are generally correlated

with income levels.

In fact, per capita income is the (and often only) development indicator used in

the literature for long-term energy and GHG emissions scenarios. This explains

why this review chapter, while recognizing the importance of alternative dimensions and indicators to describe long-term human development, almost exclusively embraces an economic perspective.9

Even though the IPCC has chosen to focus on GDP as a primary indicator of relevant societal outcomes, WG II in particular recognizes that decisions are made for

a wide range of reasons, wealth being only one of them. Also, the analysis presented

below relies on quantitative estimates of the costs of climate change damage and

climate mitigation. The IPCC states that both types of estimates are clouded by considerable uncertainties and thus although the analysis presented below relies on

specific, quantitative assumptions and conclusions of the IPCC, it should be understood in terms of its qualitative implications.

The SRES scenarios describe very different worlds:

274

10http://www.grida.no/climate/ipcc/emission/090.htm 11http://www.grida.no/climate/ipcc/emission/100.htm

All four storylines and scenario families describe future worlds that are generally more affluent compared to the current situation. They range from very

rapid economic growth and technologic change to high levels of environmental

protection, from low-to-high global populations, and from high-to-low GHG

emissions. Perhaps more importantly, all the storylines describe dynamic

changes and transitions in generally different directions. The storylines do not

include specific climate-change policies, but they do include numerous other

socio-economic developments and non-climate environmental policies. As time

progresses, the storylines diverge from each other in many of their characteristic features.10

In terms of specific economic numbers, the SRES report begins with 1990 global GDP estimated at $20 trillion (T) in 1990 dollars. It then projects future world GDP

based on different estimates of future population and per capita growth rates. The

SRES growth assumptions11 (in parentheses below) result in the following baseline

global GDP values for 2050:

A1 = (3.6 percent) $167.0T

A2 = (2.3 percent) $78.3T

B1 = (3.1 percent) $124.9T

B2 = (2.8 percent) $104.9T

These estimates do not include the costs of damage associated with unmitigated

climate change. IPCC WG II provides an estimate of future damages for a temperaVerDate 11-MAY-2000 16:04 May 12, 2008 Jkt 032966 PO 00000 Frm 00048 Fmt 6601 Sfmt 6621 C:\WORKD\FULL07\020807\32966B.TXT SCIENCE1 PsN: SCIENCE1
275

12http://www.ipcc.ch/SPM13apr07.pdf at p. 16. 13http://www.ipcc.ch/WG1¥SPM¥17Apr07.pdf at p. 14. 14The costs of aggressive mitigation (i.e., stabilization at 445–590) are estimated by IPCC WG

III to be at most three percent of GDP in 2030 and 5.5 percent of GDP in 2050 according to

WG III SPM tables SPM.4 and SPM.6. Because these values are at the top of the IPCC range,

and the IPCC does not provide a mid-range value, I arbitrarily cut them in half to 1.5 percent

and 2.75 percent in the analysis presented here.

ture rise of four degrees Celsius: ‘‘global mean losses could be 1–5 percent GDP for

4°C of warming.’’ 12 IPCC Working Group I indicates that 4°C of warming is highly

unlikely to occur by 2050 under any of the scenarios (Figure 3 below).13 So an assumption of five percent reduction in GDP in 2050, the top of the WG II range, very

likely overstates the amount of damage projected by the IPCC for 2050.

Reducing the baseline global GDP by five percent results in the following totals:

A1 = $158.6T

A2 = $74.4T

B1 = $118.7T

B2 = $99.6T

If we assume that all of the five percent in damage costs can be avoid through

aggressive mitigation then net 2050 global GDP would be the following totals:14

A1 = $159.9T

A2 = $75.0T

B1 = $119.6T

B2 = $100.4T

These figures allow for a comparison of the sensitivity of future global GDP to

mitigation policies alone versus a more comprehensive focus on differences between

different development paths. Figures 4 and 5 show this comparison.

The first column of Figure 4 shows (in grey) the $20T used by the IPCC for 1990.

The second column shows (in green) 2050 global GDP ($74.4T) under the IPCC

growth and damage assumptions for the A2 scenario which has the lowest total

GDP of the four scenario families. On top of this bar is a smaller (red) bar showing

the additional benefit ($0.6T = $75.0T–$74.6T)) to global GDP for aggressive mitigation that avoids damage. On the right hand side of the figure is a third column that

indicates 2050 global GDP ($84.2T = $158.6T–$74.4T) under the IPCC growth and

276

15 Instead assuming that damage will reduce GDP by five percent annually then the benefit

to aggressive mitigation would be $16.5T under A1 and $5.1T under A2. At 2.5 percent the values are $8.5T and $1.6T respectively.

damage assumptions for the A1 scenario which has the highest total GDP of the

four scenario families. Similarly, on top of this bar is a smaller (red) bar showing

the additional benefit ($1.3T = $159.9–$158.6) to global GDP for aggressive mitigation that avoids damage.15

Figure 5 shows the relative sensitivity of future global GDP to aggressive mitigation policies and development pathway. The inset figure (yellow box) on the lower

right shows that aggressive mitigation provides a benefit to global GDP of $0.6 or

$1.3T (depending on scenario) and choice of development pathway provides a benefit

of up to $84.4T (i.e., the difference between the GDP in scenario A1 and scenario

A2, = $158.6–$74.4T). It must be underscored that this analysis reflects assumptions explicit in the IPCC assessments.

277

16The IPCC SRES discussion of global population growth can be found at http://

www.grida.no/climate/ipcc/emission/051.htm 17The Stern Review Report on the Economics of Climate Change, http://www.hm-treasury.gov.uk/independent—reviews/stern¥review¥economics¥climate¥change/

stern¥review¥report.cfm

Because the IPCC estimates of damage related to anthropogenic climate change

and mitigation costs are highly uncertain, it is worth examining a wide range of assumptions in this analysis. Such an examination leads to qualitatively similar results across assumptions about damage and mitigation. For instance, if one instead

uses global per capita GDP rather than total GDP (as shown in Table 1 below16)

the largest difference between development paths (i.e., between A1 and A2 =

$11,388) is about 76 times larger than the largest benefit associated with aggressive

mitigation (A1 = $150).

These results hold qualitatively if one uses the assumptions of the Stern Review

report17 on climate change which included much larger estimated damage associated with unmitigated emissions (of a five percent–20 percent reduction in annual

global GDP starting immediately) with aggressive stabilization policies of costing

three percent annually, as summarized in Tables 2 and 3.

278

18 In Tables 2 and 3 the calculations use the IPCC assumptions of 1990 world per capita GDP of $3,700 and growth rates to 2050, see: http://www.grida.no/climate/ipcc/emission/100.htm

For five percent annual damage the largest difference between development paths (i.e., between A1 and A2 = $10,980) is about 19 times larger than the largest benefit

associated with aggressive mitigation (for A1 = $590). For 20 percent annual damage the largest difference between development paths (i.e., between A1 and A2 =

$7,720) is about 1.7 times larger than the largest benefit associated with aggressive

mitigation (for A1 = $4,490).

What does this analysis mean?

The conclusions to take from this analysis are as follows:

1. Mitigation provides benefits under all scenarios discussed here, and

almost all scenarios presented by the IPCC. According to the IPCC

these benefits increase as the time horizon extends further into the

future.

2. In all scenarios discussed here, under the assumptions, conclusions,

and metrics of value used by the IPCC, the importance of the development path far exceeds the importance of mitigation. Consequently,

a focus on sustainable development should be central to any discussion of climate policies. This point is in fact reflected especially by

IPCC WG II, but often it is overlooked in broader discussions of climate change policy.

3. Adaptation provides the link between sustainable development and

climate change, by ensuring that the capacity of societies to develop

is not compromised by the impacts of climate on their socioeconomic

prospects.

To reiterate, nothing in this testimony should be interpreted as being opposed to

or contrary to the mitigation of greenhouse gases. To the contrary, under all scenarios discussed here the benefits of mitigation exceed its costs. Mitigation is good

policy, and many decision-makers are now coming to understand that it is good politics, as well.

However, policy discussions about what sort of future we collectively wish to see

unfold are myopic if focused only on greenhouse gas emissions. It would be the

equivalent of a family discussion of their future focused only on their utility bill,

ignoring their health care, education, housing, and everything else that matters (or

279

19http://www.ipcc.ch/SPM13apr07.pdf, p. 18 20http://www.ipcc.ch/SPM040507.pdf, p. 33–34. 21See, http://democrats.science.house.gov/Media/File/Commdocs/hearings/2007/energy/

03may/hearing¥charter.pdf

simply how their utility bill is related to their health, education, housing, and everything else that matters). It is true of course that a family that does not focus on

its utility bill may find themselves in deep trouble. So a focus on the utility bill is

indeed important, but that cannot be the entire focus. With respect to the current

political debate about the world’s future focused on energy polices, the analysis presented in this testimony based on the assumptions of IPCC indicates that our focus

needs to be much broader—on the path of development itself. A discussion of greenhouse gas mitigation cannot substitute for that broader discussion, but should be

a part of it.

The IPCC WG II SPM recognizes the importance of a discussion of development

pathways explicitly:

. . .the projected impacts of climate change can vary greatly due to the development pathway assumed. For example, there may be large differences in regional

population, income and technological development under alternative scenarios,

which are often a strong determinant of the level of vulnerability to climate

change.

To illustrate, in a number of recent studies of global impacts of climate change

on food supply, risk of coastal flooding and water scarcity, the projected number

of people affected is considerably greater under the A2-type scenario of development (characterized by relatively low per capita income and large population

growth) than under other SRES futures. This difference is largely explained, not

by differences in changes of climate, but by differences in vulnerability.19

And so too does WG III SPM:

Making development more sustainable by changing development paths can

make a major contribution to climate change mitigation, but implementation

may require resources to overcome multiple barriers. . .

Changes in development paths emerge from the interactions of public and private decision processes involving government, business and civil society, many

of which are not traditionally considered as climate policy. This process is most

effective when actors participate equitably and decentralized decision-making

processes are coordinated. . .

Making development more sustainable can enhance both mitigative and adaptive capacity, and reduce emissions and vulnerability to climate change.20

Until our discussions of climate change are broadened to include a more comprehensive focus on development pathways, it is unlikely that we will make wise

decisions about the future, including those about the emissions of greenhouse gases.

Put somewhat differently, poor decisions about development can ruin the benefits

of wise decisions about mitigation.

Recommendations

The most immediate way that the U.S. Congress can influence sustainable development as related to climate change would be to focus as intensively on the issue

of adaptation as it has on mitigation. Adaptation allows societies to maintain their

vitality in the face of climate variability and change, and also the pressures caused

by development itself. Effective policies with respect to sea level rise, tropical diseases, and the impacts of natural disasters would complement progress on mitigation and provide benefits in the near-term, since these issues are already of considerable importance.

The Science Committee in particular can contribute to this agenda by ensuring

that the Nation’s climate research portfolio is organized in such a way so as to reflect the information needs of decision-makers facing choices about adaptation. For

example, legislation proposed by Congressman Mark Udall (D–CO) is notable for its

efforts to more closely connect climate research with the needs of decision-makers.21

In closing, the IPCC has great potential to serve as a unique resource for decisionmakers. In my opinion, it will best reach its full potential not by replicating the important work of advocacy groups that seek to reduce the scope of choice available

to decision-makers. Instead, the IPCC should serve to empower decision-makers by

280

22Pielke, Jr., R.A. 2007. The Honest Broker: Making Sense of Science in Policy and Politics

(Cambridge University Press).

expanding their view and their options in order to clearly distinguish the role of advisor from advocate, and advisor from decision-maker.22

BIOGRAPHY FOR ROGER A. PIELKE, JR.

Roger A. Pielke, Jr. has been on the faculty of the University of Colorado since

2001 and is a Professor in the Environmental Studies Program and a Fellow of the

Cooperative Institute for Research in Environmental Sciences (CIRES). At CIRES,

Roger serves as the Director of the Center for Science and Technology Policy Research. Roger’s current areas of interest include understanding disasters and climate change, the politicization of science, decision-making under uncertainty, and

policy education for scientists. In 2006 Roger received the Eduard Bru ̈ ckner Prize

in Munich, Germany for outstanding achievement in interdisciplinary climate research. Before joining the University of Colorado, from 1993–2001 Roger was a Scientist at the National Center for Atmospheric Research. Roger serves on various

editorial boards and advisory committees, and is the author of numerous articles

and essays. He is also author, co-author or co-editor of five books. Roger has degrees

in mathematics, public policy, and political science, all from the University of Colorado. His most recent book is titled: The Honest Broker: Making Sense of Science

in Policy and Politics published by Cambridge University Press.

DISCUSSION

BIOFUELS

Chairman GORDON. Thank you, and welcome back, Dr. Pielke.

At this point we will open our first round of questions, and the

Chair recognizes himself for five minutes.

Mr. Plotkin, in your discussion of transportation, you had, I

think, some positive views on biofuels. What are, in your opinion,

are the type of breakthroughs that we need to make to really fully

maximize those biofuels?

Mr. PLOTKIN. I think there are two issues we have got to focus

on primarily. The first is that if we really are serious about getting

significant amounts of biofuels into worldwide use and in use in the

United States, we have got to move past corn-based ethanol and

move to cellulosic-based fuels. And it may be ethanol, but it may

also be a variety of other fuels for transportation. And in order to

do that we have got to bring the costs way down, because right now

they are unaffordable. So that is number one. We have to continue

and maybe intensify our research and development.

And second, we really have to focus on what the effects will be

of transforming very large quantities of our land and land elsewhere in the world into what is basically going to be a monocrop.

Crops like these are nice from the standpoint of not needing a lot

of pesticides and fertilizer, at least not to the same extent as road

crops do, but on the other hand, they are vulnerable as monocrops

to new kinds of pests and problems like that. We really don’t know

at this point what will happen if we transform a large portion of

our land into those crops, so we need to study that.

FUEL ECONOMY STANDARDS IN CHINA

Chairman GORDON. And in your testimony, and I will quote here,

you say, ‘‘Some form of fuel economy or CO2 standard or agreement

is now in place in Japan, the European Union, China, Australia,

281

and elsewhere in the—and the State of California and a group of

other states are attempting to establish their own CO2 standards.’’

What are they doing in China now?

Dr. PLOTKIN. The Chinese have weight-based standards that are

somewhat similar to the standards that the Japanese have, which

are also based on weight. That is the larger the vehicle, the less

fuel economy they must achieve, which is, you know, pretty logical.

It is obviously a lot harder to get high fuel economy with a big SUV

than it is with a smaller mini car.

The difference in the Chinese standards is that they apply to

every segment of the market. That is, you can’t switch credits from

one part of the market to the other, which makes it a lot less flexible for their manufacturers to conform with that than in a situation where you can have some cars more efficient and some cars

a little less, and as long as the total fleet meets the target.

INTERNATIONAL EFFORTS

Chairman GORDON. And Dr. Pizer, you mentioned engaging in

international reassessment. There are some that are concerned

that the United States, you know, that we can’t afford to take on

this whole burden. And that we would be foolish, I guess you might

say, economically to try to do that, unless you get China and other

countries to participate. I don’t necessarily advocate that, but that

is what some would suggest. What is your suggestion on how we

can engage other nations?

Dr. PIZER. Well, I think the first step is to have a reasonable domestic policy. I think it is a lot easier to convince people to come

along with something once you have already demonstrated leadership. We already have, the European Union has in place an emissions trading program to deal with their emissions, and my guess

is if we took action, most of the other developed countries would

take action.

Engaging poorer countries like China and India that are growing

and have a lot of development needs I think is going to be harder.

I think there are a variety of ways we could do that, and just to

mention four ways right off the bat, one is through expanded use

of project-based crediting, which is currently the way the protocol

works. Two would be to try to get them to recognize policy reforms

along the lines of the energy efficiency improvements that Mr. Plotkin mentioned. They would be in their interests in reduced emissions. Third would be to try to twist their arm and get them to take

on CAPS through, you know, other things they care about internationally or just their own concern about the problem. And then

fourth would be to try to engage their private sector on deals that

would benefit particular entities like trying to get the national gas

company in China to become interested in getting a pipeline to

China that would eventually reduce their emissions.

So I think there are a variety of different ways that we can go

about it, but probably the first step is a more serious U.S. policy.

282

THE ADVANCED RESEARCH PROJECTS AGENCY–ENERGY

(ARPA–E)

Chairman GORDON. And you had mentioned in your statement

without prodding ARPA–E and the benefits. What do you see as

the benefits of ARPA–E?

Dr. PIZER. Well, I think one of the problems on the technology

front has just been the absence of a sustained commitment to develop major new technologies in the energy arena. I mean, if you

look at the pattern of public investment in energy R&D over the

past 30 years, it has been very unstable, and it has been declining.

And a lot of that hasn’t been very flexible in terms of how it has

been applied. So I think having a very serious and sustained management and support for energy research would go a long way towards dealing with one of the real pillars of the future of this problem.

Chairman GORDON. Thank you and all the other witnesses.

Mr. Hall, I now recognize you for five minutes.

ADAPTATION AND MITIGATION STRATEGIES

Mr. HALL. Thank you, Mr. Chairman.

Dr. Pizer, you, I heard your presentation as an argument for increased gasoline tax. Was that, is that correct? Did I understand

you correctly?

Dr. PIZER. I think you have to recognize that if you are going to

put into place a flexible policy to try to reduce emissions, one of the

ways that works is by raising prices to try to encourage conservation. Now, if you actually look at what we are talking about in

2030, relative to where we are now, it is actually depending on

what happens over the next 30 years. It might be an increase or

a decrease relative to current levels, but it would certainly be an

increase relative to what they would be otherwise.

Mr. HALL. And you recommend that?

Dr. PIZER. I think if we are serious about reducing a use of fossil

fuels, and we want to do it flexibly, yeah. You have to raise the

price of fossil fuels.

Mr. HALL. Is that what you mean by saying engage other nations

and show some leadership?

Dr. PIZER. I think there is a number of pieces to it, but one would

be a serious market-based policy. The other would be the support

of technology.

Mr. HALL. And the leadership you want us to show is by going

ahead and expending the money. What presumptions did you use

on China’s position when you arrived at that conclusion?

Dr. PIZER. I am sorry. Presumption about——

Mr. HALL. About China, about their participation, about their

emissions. You surely entered into some presumptions on your own

when you arrived at the figures that you have given us and you

chose the level of the year that you chose.

Dr. PIZER. Well, I was basing the numbers that I was using on

the numbers that were actually analyzed in the IPCC report. Now,

if you are asking kind of my personal opinion about this, you know,

I think that——

Mr. HALL. I will take that.

283

Dr. PIZER. Okay. You know, I think a policy where the U.S.

starts with something modest, and we could discuss what modest

means, and we expect China to follow us, you know, at some interval, maybe five years or 10 years, and if they don’t, we either go

back on what we are doing or we, you know, enact some sort of legislation to protect our domestic industries. That would probably

make sense. But I think we do have to, I think if we are going to

expect China to go forward, given their standard of living is a fraction of what ours is right now, we have to exercise some sort of

leadership.

Mr. HALL. You mean go forward by taking American jobs?

Dr. PIZER. I don’t necessarily think that the policies that are

being talked about would cost jobs. I mean, there would be switching jobs.

Mr. HALL. Do you use that in your presumption in arriving at

the conclusions you have given us here today?

Dr. PIZER. Presumption that it would cost jobs?

Mr. HALL. Absolutely.

Dr. PIZER. No. I don’t think it would cost jobs.

Mr. HALL. You don’t think so?

Dr. PIZER. No. It would be switching jobs.

Mr. HALL. Well, let us see here. Let me see how reasonable you

are. You looked at the three concentrations of greenhouse gases

and then estimated it both the year 2030, and the year 2050, as

to what it would cost to achieve these concentrations. And you used

the lowest concentration, didn’t you, in giving us your figure of

three percent?

Dr. PIZER. The three percent is associated with the most stringent stabilization goals. Yes.

Mr. HALL. Based on year 2030.

Dr. PIZER. In 2030. That is correct.

Mr. HALL. Yeah. But on the year 2050, what would your estimate

be on the percent?

Dr. PIZER. I could look at the numbers, but I am going to guess

it is probably about around three percent as well. It is a pretty constant number.

Mr. HALL. No change in——

Dr. PIZER. It might be a little bit higher, but I don’t think it is

substantially. Is it five percent? Okay.

Mr. HALL. Well, I used the middle concentration of 2050, and

these studies say that would be four percent as I stated. Do you

disagree with that?

Dr. PIZER. I would not say——

Mr. HALL. You would stay with three no matter if it is 2020, or

2050, or 2090.

Dr. PIZER. One of the things I, the first point I really emphasized

was the uncertainty we have predicting the costs. I would certainly

agree that the costs could be as high as four percent in 2050. That

is correct.

THE IPCC PROCESS

Mr. HALL. Okay. I appreciate that.

Dr. Pielke, what do you think of the IPCC process?

284

Dr. PIELKE. Overall I think the IPCC process is a sincere effort

to collect and bring the best knowledge available from the science

community, the impacts community, the economics community to

decision-makers. I do think that the IPCC process suffers from a

lack of connection with the stated needs from decision-makers. It

would be nice to have the process start with decision-makers saying here is what information we need. Here are the questions we

have, and that would shape the production of the reports.

The first IPCC assessment in 1990, had its Working Group III

focus on policy options. That changed over time. Now it is focused

on mitigation, and I think something was lost in that process

where we don’t talk about a wide range of options now.

Mr. HALL. What changes would you recommend for the future reports?

Dr. PIELKE. I would suggest something that I have often called

for a ‘‘Working Group IV,’’ where we take the science, the impacts,

the economics, and we integrate it. And we provide you folks, policy-makers, with a smorgasbord of options all the way from doing

nothing to aggressive mitigation, adaptation, different forms, with

the idea that their job is to provide you with what you can do, and

your job is to decide what you should do.

ADAPTATION AND MITIGATION STRATEGIES IN CHINA

Mr. HALL. I will ask the panel, did you all use any presumptions

that China was going to change their course when you arrived at

the three percent?

Dr. PIZER. One of the things I mentioned was that all the studies, at least in the section I worked on, generally presumed that

the whole world, you know, at some point in the future when the

studies are done, are all working together. The cost studies are

based on the idea of global participation. Yes.

Mr. HALL. That would be wonderful, wouldn’t it? Yes, sir.

Dr. LEVINE. Outside IPCC, I studied China energy, and China

has embarked on a path of reducing their energy intensity by 20

percent over the next five years. Now, they are not doing that for

CO2 mitigation. They are doing that because they can’t afford to be

investing that much in energy, and they are very concerned about

local environmental impacts.

Mr. HALL. Isn’t it impossible to get to the three percent you all

talked about if China alone stays on their present course?

Dr. LEVINE. Well, they are——

Mr. HALL. Their present course and that is why we have to judge

them on. They have given us no indication they are going to change

or help us try to cleanse the world.

Dr. LEVINE. No. They have changed courses. Their energy GDP

ratio in this past year has declined considerably. I do give you a

lot of credence for being concerned about how well they do, but

they are trying very hard to change course.

Mr. HALL. I sure hope so. I am out of time. Thank you.

Chairman GORDON. Dr. McNerney is recognized for five minutes.

285

GREEN EMPLOYMENT OPPORTUNITIES

Mr. MCNERNEY. Thank you, Mr. Chairman. I want to thank the

panel for coming out here and sharing your expertise with us.

I am going to direct my first comment to something that Dr.

Pizer said. The cost of mitigation to keep temperature rise at two

degrees Centigrade or less, which is already a very large increase

and has a very large associated global economic cost, has a very

wide possible range of outcome from plus four to minus six percent,

which means that if we mitigate, we will create new sections of the

economy which, some of which will focus on our rural communities,

creating a new prosperity in our rural areas which are now having

difficulties.

And if we, the cost of inaction or inadequate action will very likely be very, very much higher than that. So just in terms of probabilities it is a good outcome to go ahead and make the investment

in mitigation.

Now, Mr. Plotkin’s comments on the transportation reinforced

that assessment that mitigation will improve the economy. So my

colleagues on the other side of the table often focus on the taxes

and particularly on gas tax, but the panel’s testimony indicates to

me that policies can move forward without relying very much on

gas tax. Can you comment on that, Dr. Pielke?

Dr. PIELKE. Yeah.

Mr. MCNERNEY. Well, can you comment on my assessment that

investing in mitigation will actually improve the economy, especially the rural economy.

Dr. PIELKE. Yeah. I guess my view on that is at some point we

should stop debating what the economy and the climate system is

going to be in 2030, or 2050, and start doing things. And by doing

things I suggest that we start taking actions. States are taking actions, cities are taking actions on greenhouse gases, and we should

evaluate them, and those things that have net benefits, we should

do a lot more of those things, and those things that don’t work and

have costs, we should do less.

And I think the notion of improving the economies in rural locations or fostering technological innovation that stimulates the economy are all plausible, and they are all supported, I think, in the

economics literature, but we won’t know in the real world until we

actually start doing things.

BUILDING EFFICIENCY

Mr. MCNERNEY. Okay. I am going to switch a little bit to Mr. Levine. Building efficiency seems to be a very critical part of eliminating or reducing CO2, but I don’t know exactly what would be

effective in terms of building mitigating or how we get our people

that own houses to invest in the things they need to, and how do

we change buildings? Is there a new technology on the horizon that

will make this more transparent, this approach more transparent?

Dr. LEVINE. Well, the first thing you want to do is put policies

in place, and California is probably the best example. California

has been able to keep energy use per capita in buildings constant

since 1972, whereas the rest of the country has increased by I

think around 70 percent. They have done it through aggressive apVerDate 11-MAY-2000 16:04 May 12, 2008 Jkt 032966 PO 00000 Frm 00059 Fmt 6601 Sfmt 6601 C:\WORKD\FULL07\020807\32966B.TXT SCIENCE1 PsN: SCIENCE1
286

pliance efficiency standards, which has the advantage of educating

consumers. They only get to buy cost-effective, efficient appliances.

They have had very aggressive, I should say we, I am from California, so are you. We have had very aggressive utility demand

management programs, which means the utilities go in and offer

rebates and offer fixes within houses to improve efficiency within

the house. That has been very effective because it goes into areas

where consumers really just need help. And then we have had a

successful set of building codes.

So without any new technology, and there are, of course, new

technologies, we have been able to keep energy use per capita constant in the state for, how many years is that? Forty years. Now,

there are new technologies, and some of them have come in almost

automatically. There was a big push not too many years ago to get

builders to build their houses tighter when it was discovered that

leaking houses caused large losses in energy use. And that has

been very successful. It has been successful through training programs among builders, word of mouth.

We now have this sort of unfortunate situation or I guess you

could say the glass is half full, fortunate situation where we have

compact fluorescents, and it turns out that while they save threefourths of the energy and they perform very well, very well, very

few of the sockets in our houses in California have them. Well, we

need to do something about that. It is a trivial matter. The utilities

did a sensational job in California and elsewhere in getting more

efficient fluorescent lamps in.

So those are the kinds of things you can do in the near-term. In

the longer-term it is a bit of a tougher problem for commercial

buildings because you really want to have much more advanced

technology to have integrated systems that control and give you

feedback on the buildings, and for that R&D is needed, demonstration programs are needed. But we could get to, close to 0 energy

buildings over time.

Chairman GORDON. Thank you, Dr. Levine. Mr. Sensenbrenner.

MORE ON INTERNATIONAL EFFORTS

Mr. SENSENBRENNER. Thank you very much. I have heard an

awful lot of testimony this morning about raising the price of energy. I have heard the word tax. I have heard the word, substantial

tax. I have heard the words increasing the cost whether it doesn’t

involve a tax to raise the price of energy. And I have heard questions from at least two of my colleagues relative to what happens

if we do that and China does nothing.

Just by way of historical note since I am the gray beard around

here, in 1993, my Democratic colleagues voted for Al Gore’s carbon

tax, and then they voted for a big package that included an increase in the gasoline tax, and then in the next election we won

52 seats and took over control of the House of Representatives. So

I hope that the tax word is falling on very productive ears on the

other side of the desk.

That being said, I went to Kyoto as chair of the delegation in

1997, and the entire delegation met with the Chinese, and they

said no way, no how are they going to reduce any carbon emissions,

and they have maintained that position up to and including their

287

submission to the meeting of IPCC Group III in Bangkok. All of us

are getting hit by our constituents relative to the outsourcing of

jobs to countries like China and India.

And how do you expect our manufacturing sector in particular to

compete if there is a huge increase in the energy that they need

to make their products here but no increase in energy costs in

China and India? These are decisions that we as policy-makers are

going to have to consider if we are to accept any of these recommendations.

Anybody want to take a whack at that? Dr. Levine.

Dr. LEVINE. I think we have a bigger issue with the exchange

rate with China, and if we could get the exchange rate in an appropriate parity, I think many of these other issues would be second

order. We have much higher energy prices in Japan, in Europe,

and you know——

Mr. SENSENBRENNER. Well, you know, if I can reclaim my time,

the Japanese economy has been in a recession for the better part

of the last 15 years and only has recently turned around. Most European countries have got double digit unemployment. I don’t think

any of us, whether we are Democrats or Republicans, want to consign our economy to that kind of a fate. The real issue is how do

you deal with this without China and India being on board? And

what is the IPCC doing to be able to come up with a matrix that

would encourage the Chinese and the Indians to be on board, because they would view it as in their economic best interest. I

haven’t heard anything lately on that.

Dr. LEVINE. IPCC doesn’t do anything. They are very advisory,

and this is within the realm of——

Mr. SENSENBRENNER. But IPCC is giving advice to policy-makers.

We are policy-makers. We are policy-makers where our existence

here is dependent upon our voters sending us here. And listening

to the prescriptions that you and the panels at the previous hearings have had, I am supposed to be the happy bearer of good news

saying we are going to increase your taxes, we are going to double

your electric bill, we are going to double your natural gas bill, and

we are not going to make China do anything. So when everybody

gets thrown out of work, you know, then I guess we will increase

the deficit to provide some kind of an adjustment program for you.

Now, that is not a winning political matrix for anybody, is it?

Dr. PIZER. If I could just respond to the first point that you were

talking about. It definitely does not work for the U.S. to pursue a

policy that is adverse for its economy period. But it is also not sensible for the U.S. to do something that raises its energy prices if

China and India don’t do anything, and all of our industry just goes

over there and emits over there. It doesn’t help the economy, it

doesn’t help the environment.

So the question is what do we do in order to bring China and

India along, and I guess my argument is that we have to do a lot

of different things, and one of them is probably take a modest first

step. I don’t think we do something that has dramatic impacts, but

we do have to take something that says that we are serious and

convince them to come along with us.

Mr. SENSENBRENNER. Thank you. My time is up.

Chairman GORDON. Mr. Carnahan is recognized.

288

EFFICIENCY TECHNOLOGIES

Mr. CARNAHAN. Thank you, Mr. Chairman, and thank this panel.

It has been very insightful and inspiring to hear some of the possibilities that are there and pulling this information together can

help us with our public policy.

I will tell a little bit about our experience in St. Louis. We had

a prominent building company there, a prominent construction

company, that renovated an older structure, has gotten the platinum lead certification, the top, I guess, green building certification

you can get internationally. Was so successful in doing that with

their own building, and the business executives there talk about

the economic benefit to their company, the long-term savings they

are going to have with those things they have designed into the

building, they actually created a green building design subdivision

of the company, and they are going out and selling this. And we

have had a lot of international visitors come to St. Louis to see

this, to see how it can be done, and so, you know, this is a winning

business model, a winning economic model that people are using,

and we seen that locally at home.

And I wanted to ask Dr. Levine about, you know, the testimony

about by 2030, about 30 percent of the emissions could be saved.

And really if you could just list off what are some of the technologies or practices that help us get to that point that we need

to be focusing on.

Dr. LEVINE. The biggest growth areas in both residential and

commercial buildings is plug loads, things you simply plug into

wall outlets and when they are not on, they are hot, and that is

when they are not producing anything useful, they are producing

heat. What we need to do is to develop a chip so that when they

are plugged into the wall, they are effectively not doing anything,

and you are saving electricity.

Mr. CARNAHAN. That would be something built into the plug

itself or into the appliance?

Dr. LEVINE. Into the gizmo that you plug into the wall.

Mr. CARNAHAN. The plug itself.

Dr. LEVINE. The plug itself.

Mr. CARNAHAN. Okay.

Dr. LEVINE. Yeah. And right now the estimate is that you have

the equivalent of a refrigerator worth of, one to three refrigerators

worth of those things in your house. So they are a very large savings that you just aren’t aware of.

Mr. CARNAHAN. Has that chip been developed? Is

that——

Dr. LEVINE. It is under development and not yet available in all

applications. You know, you have set-top boxes on your TVs that

are using 20 plus watts, and they could be using two to three

watts. We need to get industry agreement to cut them down to two

to three watts, and that is a process that is going on right now.

Mr. CARNAHAN. Where is that being done?

Dr. LEVINE. Well, EPA has an Energy Star Program. We are involved in it and trying to congeal the manufacturers. The California Energy Commission is trying to make a pest of itself in getting appropriate attention. The windows can be better. We are

289

working on the next generation of windows that are dynamic windows that respond to different temperatures outside. I think for

residential buildings insulation is in pretty good shape. There is

still ways of reducing air infiltration, particularly in the ductwork

in residential buildings, and there are now technologies to do that.

And I don’t want to go at length on this, but I do want to say that

the, I want to say two more things.

Commercial buildings are actually a very unfortunate situation,

large commercial buildings. They have had very, very little attention on R&D, and the opportunities are very great. They are systems, and so it is very hard to do R&D in a system instead of widget. And so we need to treat them as systems, and we need to work

on them as systems, and we need to do demonstrations with control

systems and the building interacting.

And then, of course, for the longer-term you want to have building-integrated floatable tank systems in buildings. That is not

available now, but it will be in due course one hopes.

MORE ON BUILDING EFFICIENCY

Chairman GORDON. Thank you, Dr. Levine.

Just for the information of the Science Committee Members,

former Chairman Boller a few years ago asked the Carnegie Mellon

University to do a research project on the Science Committee and

energy efficiency. We have picked that up and talking with the

Speaker this fall the Science Committee, all of our rooms will be

made a model for the Capitol in terms of energy efficiency.

Later you are going to see, I have got quite a bit of legislation,

which is concerning energy efficiency within commercial and residential buildings, most of which will come through this committee,

almost all of which is off-the-shelf technology now that is not, you

know, anything that is way outside. The commercial residential

section is the largest user of energy, and I think there is a lot of

things we can do.

One thing I think is of interest, and I think certainly the Federal

Government should take the lead, but what will happen oftentimes

is an agency will say, well, you know, we don’t have enough money

as it is, so we can’t waste it, not waste money, but we can’t use

money on insulation or more expensive light bulbs because our

budget is too tight. So we want to create a revolving fund so that

agencies can come to this revolving fund and with a plan of ‘‘X’’

amount, again, off-the-shelf types of insulation or changes, that will

cost a dollar, and some expert will say that the savings can, you

can repay that with your energy savings over three years or four

years, and so they will pay that back in. So we are going to do, I

think, some creative things. Again, off-the-shelf things that should

hopefully continue our unanimous—yes, Mr. Bilbray.

Mr. BILBRAY. Mr. Chairman, I come from a state from where we

only use two forms of energy from an air pollution point of view.

We talk about putting in the light bulbs and everything, but as

long as the United States Government in Washington is generating

its electricity out of the dirtiest technology and the highest emitter

of carbon, I really find it interesting that we are talking about five

percent reduction doing this and this when the elephant in the

room is not being addressed. And the fact is that we have, since

290

1992, the Federal Government has tried to decommission zeroemission generators, such as hydroelectric. But as long as we are

looking down the pipe of coal-burning Congressional facility over

here, I really have a problem with us having a moral high grounds,

setting an example for the rest of America. My little old constituency out there, well, the fact that what Congress does to generate

the electricity for this facility, you would go to prison in California

for.

So I just want to say as we talk about all these neat things, I

am still in culture shock when I come back here and see those coal

trains coming in, and I know it is an inappropriate thing. It is not

politically correct to say right now, but I just say again, we have

got to confront this issue, and we have got to address the source

of the emissions, which is the power plants.

And I yield back. Thank you, Mr. Chairman.

Chairman GORDON. Thank you. We want to see you come out of

shock, and that is the reason that the Speaker has already introduced a Green Capitol Initiative. That is the reason that we got approval to do the science room. The, certainly the coal-fired plant is

of real interest. I would point out that most of the, what looks like

the gray stuff that is coming up is steam.

But you are right. And there needs to be a change, and I think,

and the Federal Government needs to take the lead, and you are

going to see that start to occur.

And Mr. Rohrabacher is next.

ANTHROPOGENIC CAUSES OF CLIMATE CHANGE

Mr. ROHRABACHER. Thank you, Mr. Chairman, and I certainly

appreciate my colleague from California who along with this Member of Congress enjoys transportation vehicles that have totally renewable, based on renewable energy in terms of title and wave-related energy sources. We both, of course, live on the ocean.

Let me just note, and then we will go into a more detailed discussion about it right now, what we are talking about is based on the

idea that manmade global warming is a reality, and of course that

I totally reject. And I might add I have put on the record numerous

scientists from MIT and other major universities throughout the

world who disagree with that and think that it is basically being

used as a football to push other agendas. That is the analogy I

guess having a football to push agendas but as a method of pushing other agenda.

I would like to put a quote on the record here by Timothy Ball,

who is, of course, a professor of climatology at University of Winnipeg. ‘‘I, believe it or not, global warming is not due to human contribution of carbon dioxide. This, in fact, is the greatest deception

in the history of science. We are wasting time, energy, and trillions

of dollars while creating unnecessary fear and consternation over

an issue with no scientific justification.’’

Let me add that Dr. Ball’s observation is not different than I say

than many, numerous other scientists who now have been just totally ignored in the public debate in order to move forward with

these very revolutionary concepts of what we should be doing to

curtail or change the economic way, and the technological way that

we manage our society.

291

Back to today’s hearing about what we are really talking about

is IPCC and what was recommended there. I have a quote here

from Dr. Christopher Landsea, who was taught by NOAA and received his doctoral degree from Colorado State University in atmospheric sciences. He was part of the IPCC effort, and he said, ‘‘I am

withdrawing,’’ meaning from the IPCC, ‘‘because I have come to

view the part of the IPCC to which my expertise is relevant as having become politicized. In addition, when I have raised my concerns

to the IPCC leadership, the response was simply to dismiss my concerns, which I have seen so often where people just want to say the

debate is over, and not handle the actual specific arguments that

are being presented by those who question this.’’

And then I go on with Dr. Landsea, ‘‘I personally cannot in good

faith continue to contribute to a process that I view as being both

motivated by pre-conceived agenda and being scientifically unsound.’’ Now, first of all, I would like to ask the witnesses that

were part of the IPCC process is Dr. Landsea just some guy who

is dishonest about this, or is he someone who has raised some serious concerns about the IPCC process?

Chairman GORDON. Mr. Rohrabacher, we have two votes coming

up. What I would suggest is the witnesses to answer your question.

We will then go to Mr. Lampson and see if we can get that one in,

and then witnesses, if you will excuse us for about 30 minutes, we

have to go vote, and we will be back.

Mr. ROHRABACHER. Mr. Chairman, does that mean that possibly

I could have the rest of my five minutes when we come back?

Chairman GORDON. Do you want to start all over, or you could

let them, you had a minute, 30 seconds left if you would like for

them to complete.

Mr. ROHRABACHER. Thank you. Go right ahead and answer and

then I have got one other thing to put on the record.

Mr. PLOTKIN. Well, first of all, we were working on a different

part of the assessment. I guess your gentleman was working on the

science part, the first part. We are working on mitigation. There

are a lot of people involved. It occasionally got sort of chaotic. I did

not feel that it was a political process at all, and it is also a process

that is, I come from an agency, an office of technology assessment,

which had a really extensive review process. This was far more extensive than that, and that in my career, that was the most intensive.

So I think that a lot of that is filtered out if it gets into the system anyway.

Mr. ROHRABACHER. We have one scientist who was part of it who

felt that it was totally compromised.

Mr. PLOTKIN. Part of a different part. I have no idea what went

on, and I don’t think any of us do——

Mr. ROHRABACHER. Let me just——

Mr. PLOTKIN.—on that particular part of the analysis.

Mr. ROHRABACHER.—for the record I am going to put this article

into the record from Newsweek Magazine by Richard Lindzen, who

is an MIT professor, very respected man, who says, ‘‘The current

alarm rests on the false assumptions that not only that we live in

a perfect world temperatures but also that our warming forecasts

292

for the year 2040, are somehow more reliable than the weatherman’s forecast for next week.’’

And let me know even today from what your testimony is, I

heard the words, best guesses, I think were the words that I jotted

down, and in terms of what these models that we are talking

about. We should not be doing something that will affect the standard of living of people who in our country, middle Americans who

earn $50,000 a year, affect them dramatically, which is what I

have heard, based on these type of charts which are being called

into question, these types of projections that are being called into

question by some of the top scientific minds on the planet who are

being ignored in this debate.

Chairman GORDON. Thank you, Mr. Rohrabacher.

And Chairman Lampson, if you would conclude this section.

MITIGATION OBSTACLES

Mr. LAMPSON. Thank you, Mr. Chairman. I may give you back

a little of time. I will try.

I would like for Dr. Levine to talk for just a minute about maybe

more you have already perhaps already done some of this, but obstacles that keep commercially-viable technologies from widerspread use in the country. And I think that your Summary for Policy-makers includes a table with a number of building relevant

mitigation strategies that are available. What are some of the obstacles? Why aren’t more people more anxious to do those kinds of

things?

Mr. LEVINE. I think one of the biggest problems is transaction

costs. How much time do you have to shop? How much time do you

have to shop to get the most efficient product, and how do you

know that it really is the most efficient product? And so people

really have limited time.

Another aspect of that is availability of technology. Turns out interestingly that appliance manufacturers were not making the

most efficient appliances that would sell on the market because

they had a marketing strategy that gave them a better return by

not doing do. And so until appliance standards came in, they had

no incentive to put more efficient technology onto the market.

You have got extremely complex design processes for commercial

buildings, where you have engineers doing one thing and architects

doing another thing, and they don’t talk to each other. And everybody gets paid based on how much time it takes to do the design,

and nobody gets paid on how much energy savings you get in the

design. So the design process itself if flawed. It is often difficult to

get extra financing for more efficient products.

Mr. LAMPSON. And we trust the efficiency guides that are placed

on appliances today?

Dr. LEVINE. I think we do now. Yeah. The EPA has done a terrific job in its Energy Star Program so that that problem has in

good measure been overcome. And also Appliance Standards I

think has done a very good job.

Mr. LAMPSON. Let me——

Dr. LEVINE. But, you know, it is sort of, it is a matter of trust.

You are dealing with these gizmos. You don’t know what they are,

293

and whom do you trust? You have salespeople at one end and the

other end. It is a tough job.

Mr. LAMPSON. Indeed. Let me just ask Dr. Plotkin if I may. You

made a comment about if the U.S. new car and light truck fleets,

fuel economy would have been 24 percent higher had we not

changed the weight of the vehicles. Would you comment on that

and also on the weight or body shape changes as far as automobiles

are concerned?

Mr. PLOTKIN. Well, I think in vehicles there is a little, something

a little different happening than in buildings. If you, I don’t think

there is a lot of tradeoff in buildings with energy savings. You got

a more efficient air conditioner, you are going to use it to save energy. Unless you decide to chill your house a little bit more. But

in vehicles, making a vehicle more efficient or a technology that

can make a vehicle more efficient can be used either for fuel economy or it can be used to improve performance or make the vehicle

bigger. That is sort of similar to a house. You can make the house

bigger, obviously, if you can produce the energy savings.

Chairman GORDON. Will the gentleman yield back? I am sorry.

We are getting close on time.

Mr. LAMPSON. Yes.

Chairman GORDON. Let me make this suggestion. It is my understanding that we have a motion to adjourn, which will be followed

by 10 minutes of debate on the National Defense Authorization

Bill, and you know how long 10 minutes can go. And then we will

have two votes. So what I would suggest, I don’t mean to be overly

inconvenient to you folks, but I would suggest let us go vote and

then come back here between the debate, you know, starting with,

you know, we can get several questions in, and Mr. Plotkin, I understand you have to catch a plane, and your presence has been appreciated, and you are excused, and we will, if there is no objection

we are going to come back after this vote, and if we can finish, we

will.

[Recess.]

Chairman GORDON. The Committee is back in session, and Dr.

Ehlers is recognized.

MITIGATION COSTS

Mr. EHLERS. Thank you, Mr. Chairman. My first question is for

Dr. Pielke. First of all, I appreciated your suggestion that the concentration of IPCC should be on recommendations for policy-makers. I appreciate the work they do, but it would be helpful to have

it translated to meet our needs. On your charts, perhaps I didn’t

quite understand it, but you showed very small mitigation costs

compared to economic growth, as I recall. Did I understand that

correctly?

Dr. PIELKE. That is correct.

Mr. EHLERS. Okay. Now, were you implying that we can forget

about mitigation because the costs are so small compared to our

economic growth, or are you trying to say we should mitigate because the cost is really so small compared to economic growth?

Dr. PIELKE. I guess I would say ‘‘small’’ is a relative term because we are talking about trillions of dollars and so if you can

benefit the global economy by a few trillion dollars, then we should

294

do that. So the message from that is that mitigation provides a net

benefit. But the broader, bigger picture is that, that is the not the

only set of decisions we have to make about our long-term economic

future. And the difference between the low-GDP future envisioned

by the IPCC and the high-GDP future is something like $80 trillion, which is about 80 times larger than that mitigation benefit.

I guess my overarching point is that we should be paying as much

attention to achieving that $80 trillion as we are to achieving that

$1 or $2 trillion by 2050.

DEVELOPING COUNTRIES

Mr. EHLERS. Okay. Now, how do you see this relating to less developed countries or even countries which are rapidly developing

such as China or India? How do you see their decision-makers reacting to this?

Dr. PIELKE. Yes, I see this as the key question, and I appreciate

that you asked it because in the discussion earlier about China, I

think this point was missed. China is not something to fear, the

rapid development in China is an opportunity. China is using enormous amounts of expensive energy. If the United States through an

innovation agenda, investing in the development of cleaner, cheaper, energy technologies gets there first, then the Chinese are going

to rush to buy our products. So it seems to me that if we think

about not just climate change but about innovation, competitiveness, as a much bigger picture, the development in China is nothing to be afraid of or that it should limit our action. It is really an

opportunity, particularly for the science community, to invest

money in innovation that puts us out in front so that our economy

grows, and we capture some of that $80 trillion in growth.

Mr. EHLERS. Well, I totally agree with you on that. I am dismayed that some of my colleagues here in the Congress seem intent on making China into an enemy whereas I like to see them

as a potential customer, not just as a supplier but as a customer

of us. A good example might be in terms of what IPCC worries

about would be nuclear development in our country. We have not

done a good job of developing nuclear plants. But if we made an

effort at it, we would have a very large market in China. Right now

I am afraid that market is going to go to France or some other

countries, simply because we are not latching onto it. So I appreciate your comment on that.

MORE ON BUILDING EFFICIENCY

Also a general comment for both of you, if you wish to comment.

Mr. Chairman, you made some comment about how we must not

look at the energy savings just in terms of cost; we must look at

the other benefits as well, the other issues involved. I certainly

agree with that. I have been gung-ho about energy efficiency for

years. In fact, back in the mid-seventies, I got fed up with the insulation in my house. It was done according to standard practices,

but I redid it myself, you know, plugged the air holes where the

cold air, in Michigan you get a lot of cold air was getting in. It filtered down from the attic into the walls from every opening that

that you made for electrical outlets and everything. I sealed everyVerDate 11-MAY-2000 16:04 May 12, 2008 Jkt 032966 PO 00000 Frm 00068 Fmt 6601 Sfmt 6601 C:\WORKD\FULL07\020807\32966B.TXT SCIENCE1 PsN: SCIENCE1
295

thing off, sprayed the insulation back in, and shaved one-third off

my utility bill. Now, that is a very substantial savings. However,

if I had hired someone to do it, it would not have been much of a

saving. But the fact that I did it myself, I earned a lot of money

very easily. I don’t know how we address that. If either of you have

any ideas of how we can change either the system or change the

mentality so people are more prepared to spend money on energy

conservation. And I am not talking just about individuals. I find

the business sector that way too. I have never understood why in

the business community they are totally gung-ho about efficiency

of operation, efficiency of distribution and all that, but you talk energy efficiency to them, this is a silly, fuzzy-headed, knee-jerk liberal idea and it is still money. And when EPA did the Green Lights

Program, it was a real eye opener to industry that they could see

that much money just by replacing the lighting. So I don’t know

if either of you have any comments on that.

Dr. PIZER. Well, I think one possibility is improved information

programs, probably through the utility companies, to make people

both more aware of these opportunities that exist, as well as providing them with loans potentially to try to—if they don’t actually

want to install the insulation themselves, to hire someone to do it.

I think that is a big piece of it. Another possibility is to think about

tighter building codes. That is usually something that is done more

at the State and local level, but, you know, requiring builders to

actually to use more efficient—more insulation when they are

building houses would go a long way towards dealing with that

problem.

Mr. EHLERS. Well, actually that is the most cost-effective way to

do it is through a building code because redoing a house later is

far more expensive than doing it right the first time.

Chairman GORDON. The gentleman’s time has expired.

Mr. EHLERS. Just one last comment on the utilities. The difficulty with the utilities is that they make more money by selling

more energy so you have to totally restructure the reimbursement

mechanism for the utility.

I yield back.

Chairman GORDON. Thank you, sir.

Mr. Smith is recognized.

CHINA’S COAL ENERGY PRODUCTION

Mr. SMITH. Thank you. I regret that our witnesses are disappearing, but I will try to make it quick. Perhaps anyone on the

panel can respond, but earlier statements suggested that we need

to get away from corn ethanol and transfer to switchgrass. If either

of you can speak to the energy content or renewable energy content

of a bushel of switchgrass compared to a bushel of corn, if you

could speak to that. Also, a statement was made by the gentleman

who had to catch an airplane about mono-cropping relating to renewable energy, if you could comment on that. And then also we

heard earlier from my colleagues about coal and about China’s approach, and if you have the data on China’s coal energy production

now, how many plants are due to come online, whether or not it

is clean-coal technology, and then also, I don’t know, maybe it was

Dr. Levine who said that China is already striving to be I think

296

more energy efficient or something. Anyway, in my estimation, this

is suggesting that market-based approaches are being engaged in

China.

I realize that is a lot of questions for a short period of time, but

I do want to speak to the issue that market-based approaches are

working a great deal. I find it very hard to imagine that my good

friend from Michigan accuses businesses of ignoring the cost savings of energy efficiency, and those are my words. I don’t want to

change your words. But already the desire to engage in capitalist

economy many times works. I am afraid—I visited India, and the

environment there is very, very concerning to me. And then I come

home—and Mr. Sensenbrenner certainly spoke to the fact that we

get beaten up politically over all these jobs going to Asia and to

think that they would be exempt when we would not be. So if the

panel would care to respond, perhaps Dr. Pizer, if you would begin?

Dr. PIZER. I am going to skip the switchgrass versus corn ethanol. That is not really something I could speak well to. Unfortunately, Mr. Plotkin had to leave. Let me talk a little bit about, I

guess, coal, because that is something I know a little more about.

There was a recent study done by MIT, the MIT coal study, which

really looked at this problem in a lot of detail. And I think one of

the conclusions of that study is that coal is an incredibly important

part of our energy mix as well as of China’s. And to answer your

specific question, I think they are building something like the

equivalent of one 500-megawatt plant every couple of weeks basically to feed their rising demand for energy, and these are not the

most efficient plants in the world that they are building.

So the recommendation of the study, recognizing the importance

of the climate change issue, was really to call for a large research

effort on capture and storage technology for coal plants. Because if

we are going to continue to use coal in this country, and China is

going to continue to use coal as well, that is going to be a really

critical technology. So at this point, it is something that needs—

there needs to be a regulatory framework. There needs to be largescale demonstration projects and that is kind of the key story for

coal. Dr. Levine might be able to speak to the energy efficiency programs in China a little bit better than I could. I guess I would say

on the trade side, that keeps coming up, for a modest program to

get started, the consequences for trade are in the noise. I mean,

there are a lot of things that are going on that are problems for

American industry and we need to really seriously work on those

problems but I do think that it is possible to get started and eventually get China along with us without having an adverse impact

on jobs in the United States.

Mr. SMITH. If I might interject, also on the taxation suggestions,

that taxing energy would lead to more conservation. Certainly that

can be the case, but I would suggest—I can’t remember, and I

apologize, which member of the panel suggested that recycling tax

dollars would lead to great economic results. Would you suggest

that the same dollar in taxes would leverage better results than a

dollar—the same amount in the private sector with capitalist objectives?

Dr. PIZER. I think the point that was being referred to was a general theory of taxation. Tax—when you tax something it generally

297

discourages it because it costs more, and if we have a choice, usually we like to tax things that are bad like pollution as opposed to

taxing things that are good like labor and capital. And so the obvious point is that if we were to switch off of some of our taxes on

labor and capital and put more tax on pollution like carbon dioxide

emissions, we could actually increase the efficiency of the tax system, and that is a benefit to society.

Mr. SMITH. Dr. Levine, while you were out of the room I was inquiring about China. I think you made some statements about China’s efforts already underway in terms of more efficiency, and I am

assuming that you meant more environmentally friendly. Now, it

is my understanding and as Dr. Pizer pointed out as well, that new

coal plants are coming online in China without clean-coal technology that make our efforts seem pretty pristine. Would you speak

to that?

Dr. LEVINE. Yeah. I would disagree a little bit with Dr. Pizer.

Most of the coal plants coming into China are at least efficient, but

they are not designed for carbon capture and storage. Neither are

ours. And so we find ourselves in exactly the same situation. The

problem in China is that they are building so many. They are

building—they have this tremendous construction activity in coalfired power plants in China, and this is frightening.

Now, what is to be done about it? The best thing to be done

about it is to cut demand, and the Chinese have been slow to move

in that direction. Up until 2000, they had been effective in cutting

the growth and demand, and then it got away from them. They

have now embarked on a program to cut the growth in energy intensity by 30 percent in five years. This is a remarkable goal. It

is not only a goal. They have organized their industry, and they

have given quotas to industries. They have given quotas to cities.

They have put governors under pressure where if they don’t do the

right things, they stand to lose their jobs. They are attempting to

create a bureaucracy that will once again provide incentives and no

doubt punishments for accomplishing these objectives.

Chairman GORDON. The gentleman’s time has expired. Vice

Chair Lipinski is recognized.

ENERGY EFFICIENCY PRIORITIES

Mr. LIPINSKI. Thank you, Mr. Chairman. I would like to thank

all our witnesses for their testimony today. I think that what we

really need to, of course, focus on first is a very low-hanging fruit,

and last night I was in the Rayburn garage, and I saw them putting in CFLs and was, you know, happy to see that as part of our

Green Capitol Initiative. I have an amendment today of the DOD

Authorization Bill to require the DOD to use high-efficiency bulbs

where practicable. I also have a bill to require GSA buildings to

use high-efficiency bulbs, put in high-efficiency bulbs when they

are replacing bulbs. It seems that high-efficiency lighting is certainly such an easy way to, you know, save energy and you also

save money, which is not something that you always find when you

are saving energy.

That leads to my question here. All the recommendations that

you have given, I appreciate hearing all these and hearing your expert testimony on them. What I would like to ask for is

298

prioritization of these, you know, ways to go about, you know, helping reduce greenhouse gases and saving energy. How would you

prioritize them? Like I said, I would think you go after the lowhanging fruit first, things which are less costly and save the most,

and, you know, just balancing those things out. What do you think?

And I will ask—I will start with asking Dr. Levine. Just quickly

what would you prioritize that we here do first to work on this

problem?

Dr. LEVINE. Well, the highest priority is efficiency. You do well

in buildings, you can do very well in industry, not so widely known,

and you heard from Steve Plotkin that we have a long way that

we can go in transportation at low cost or net benefit.

Mr. LIPINSKI. Now, do we——

Dr. LEVINE. Those are the first things you do.

Mr. LIPINSKI. In terms of efficiency, what type of requirements—

obviously you could talk CAFE standards with automobiles or what

other ways do we get there to be more efficiency in various industries?

Dr. LEVINE. Well, those ultimately are political questions.

Mr. LIPINSKI. Well, that is why we are asking you for what the

easiest way, you know, has the most impact.

Dr. LEVINE. Look, for industry my own personal preference would

be to have industry agree to voluntary standards they take seriously. I think they can do it. I think you have seen it done in other

countries, but this is sector wide. This is not, you know, plant by

plant. For cars, you know, auto fuel economy standards, alternatives to gasoline. I have already talked about, I think, what the

best policies are for buildings. I think when you get into the supply

side, you are going to talk about some taxes and R&D, and you

have to talk about R&D for efficiency as well, and you would like

to recycle whatever the taxes are into R&D.

Mr. LIPINSKI. Okay. Dr. Pizer, one or two things?

Dr. PIZER. Yeah. I think I am a little bit more skeptical maybe

with all due respect to Dr. Levine about the voluntary programs.

The work that I and some colleagues have done suggest that there

are some opportunities to get reductions and improvements in energy efficiency from voluntary programs, but they are usually limited to maybe five to ten percent. And if you really want serious

activities, in the long run you are going to have to have something

stronger, although five or ten percent wouldn’t be a bad start, I

guess.

The other thing that I think is a really important priority is

sending signals to businesses so that they invest in new technologies and R&D, and I think that, you know, there are a variety

of different ways to try to send that signal to business, but one of

them is to suggest that the future is going to be somewhat different. If we really care about greenhouse gas emissions and the

future is going to be about reducing those emissions in more and

more serious ways, we need to convince business of that. Because

if they keep making the same investments to improve conventional

technologies, then we are never going to get the investment in the

newer technologies that we need.

Mr. LIPINSKI. Thank you.

299

Chairman GORDON. If the gentleman would yield back then, Ms.

Biggert is recognized, and we would like to—has the 15 minutes

started? Okay. You know, I would like for our three remaining

Members to have a chance the best you can here in these next 10

minutes to get your questions in.

Ms. BIGGERT. I will be short.

I know that Dr. Ehlers mentioned nuclear energy, and I think

that is something that we really have to look at and what happens

all the time is we look at the short-term and then don’t move ahead

with the nuclear, particularly when the gas prices go down. We

seem to be lulled back into not looking at reducing our dependence

on foreign oil and gas. So I think that that always has to be in forefront, and you know, we are talking about what, $2 billion probably

to build another nuclear plant, but there are companies now who

are already looking at getting the licensing and things. So I think

that they are moving ahead.

A few years back then-Secretary of Energy, Spence Abraham,

came to my district and to Argonne to look at the fuel cell for the

hydrogen cars, and it was a big fuel cell, and he said, how long is

this going to take before we will see it in cars. And I have already

driven a hydrogen car around the streets of Washington, which is

kind of scary because it is a $1 million car right now, and I don’t

drive around the streets of Washington that often. But I think as

we move ahead, I was a little disappointed to hear that we haven’t

done anything, because I think EPAct, the 2005 energy bill, really

had a lot in it. Unfortunately, everybody focused on the fact that

we were for oil and gas, the tax credits, but there were a lot of tax

credits. For example, we have a bill in the Energy and Environment Subcommittee for contractors, for architects who develop an

energy-efficient building. I think we are moving ahead so much,

and I don’t know whether we need to combine that all into this one

big project, but the President has the Advanced Energy Proposal

and GNEP for nuclear, and so I think what you are doing is great.

I think we need to look, say that we are doing these things and

to find the ways to, you know, increase the need for it, increase the

visibility of our plans because it is crucial.

But—so I am not going to ask a question. I am just going to

make a statement. I yield back.

Chairman GORDON. Thank you, Ms. Biggert, and Mr. Bilbray is

next.

NUCLEAR ENERGY

Mr. BILBRAY. Yes, Mr. Chairman. Gentlemen, I hear about the

retrofitting and whatever, and I am just trying to picture in my

years at air resources in California, California reduced its emissions by 50 percent. The air is twice as clean now as it was 20

years ago with twice as much population. There is no way we

would have done that talking about retrofit. Stationary sources are

where we have made the major reductions.

When it comes down to zero generators, have you guys specifically addressed the transformation from fossil fuels to nukes, either

fission or fusion?

Dr. PIZER. I think most of the studies of stabilization have a hard

time doing that without some increased role of nuclear power. CerVerDate 11-MAY-2000 16:04 May 12, 2008 Jkt 032966 PO 00000 Frm 00073 Fmt 6601 Sfmt 6601 C:\WORKD\FULL07\020807\32966B.TXT SCIENCE1 PsN: SCIENCE1
300

tainly the higher-end estimates are, you know, that is what a lot

of times drives it is constraints on nuclear power. There are obviously a lot of problems with nuclear power as the previous person

mentioned, but those are probably going to have to be dealt with

if we are really serious.

The other big——

Mr. BILBRAY. Before you go——

Dr. PIZER. Sorry.

Mr. BILBRAY.—to the problems, what is the cost comparison between nuclear and other alternative, zero generation facilities?

Dr. PIZER. For base load, and my colleagues here can correct me,

but for base load I don’t think there really is an alternative right

now for zero emissions. I mean, unless you are talking about expanded higher power, things like wind and photovoltaics and centralized solar power, you know, are not going to be cheaper, and

wind isn’t really base loads. So, you know, I think that that really

is the alternative. Over the longer run I think people are very excited or hope for coal with capture and storage.

Mr. BILBRAY. And what?

Dr. PIZER. Coal with capture and storage.

Mr. BILBRAY. Well, that is an interesting thing, because I will

tell you something. We talk about capture and storage. It is tough

enough to find a disposal site within one State. When we talk

about putting it two miles down with three-State jurisdiction and

then people will raise later, what about this, the questions. I just

think the capture and storage is sort of being treated as if it is not

issue. It is a huge issue and regulatorily it is a huge issue.

Mr. Chairman, just, I know my time is—we are on short time.

Chairman GORDON. Yes. Why don’t you ask one more question,

and then we will give the rest of your time to Mr. Gingrey if that

is okay.

Mr. BILBRAY. The question is this. There are three major opportunities here. One is nuclear, one is hydroelectric and the other is

biofuel, but biofuel needs genetically engineered organisms to make

it practical. Wouldn’t you agree with that?

Dr. PIZER. It is not really my expertise. I might ask some of the

other people to comment on that.

Dr. LEVINE. I tend to agree with that.

Mr. BILBRAY. Yes. So, Mr. Chairman, my point being that the

three major options for generating are those that have been actively opposed by people who claim they are supporting the environment. We have to break those taboos, stomp away from the sacred ground, and move into practical applications that the three

technologies we are talking, we got to think about when we talk

about destroying hydroelectric dams, what is the real big picture

here, not just what is the micro picture. We have got to talk about

next-generation nuclear, and we got to talk about genetically altered enzymes to be able to produce the biofuels that everybody

touts, but when we get to genetically altered, you watch. The people will come out of the woodwork to oppose it, and we have got

to find reasons, to find answers rather than always excuses to oppose it.

Chairman GORDON. Thank you.

Mr. BILBRAY. And thank you very much.

301

Chairman GORDON. Thank you, Mr. Bilbray, and the last word

to Mr. Gingrey.

FUTURE IPCC REPORTS

Mr. GINGREY. Definitely not the last word but I thank you, Mr.

Chairman.

Would all three of you briefly comment on the thought of maybe

having a Working Group IV of the IPCC that was made up of

maybe not pure scientists? You have made your case I think pretty

well, although my friend on the upper row, Mr. Rohrabacher, would

not agree with me on that. But it seems to me that a lot of the

discussion that goes on is, well, what do we do about it, and what

is the most cost-effective way? Twenty years from now, how much

will we be dependent on coal? Dr. Barlett talks about that a lot,

and you know, will there be cap and sequestration technology?

Hopefully there will be, but it just seems to me that a Working

Group IV, if you want to call it that, under the IPCC to say, okay,

now, we have got the scientific facts that we have accepted, what

is the best, most economical way, what is best for our economy,

what is best for our health. What do you think about that?

Dr. PIELKE. I think that doing it via the IPCC might be difficult

because it is an international organization and all the international

politics involved, but in the United States this could be done right

away. And in 1992, the National Academy of Sciences published a

massive report called Policy Options on Climate Change, a big

green volume, and in it they surveyed a whole wide range of options, mainly energy policy, some adaptation. But this committee

could very easily motivate such an entity to update this report.

What are our options for mitigation, for adaptation? Both narrowly

focused on the climate issue but focus broadly on what actions can

we take that has a side benefit of reducing emissions. And you

could have a report next year, and I think the sooner that sort of

thing would be done, the faster you can get input into——

Mr. GINGREY. Yeah, because, let me just interject. I mean, you

pick your poison. Would you rather starve to death in 10 years or

choke to death in 20, when you get right down to it.

Chairman GORDON. The Chair would be happy to work with Mr.

Gingrey in trying to develop something like this.

Let me say this has been a modified type of hearing today. I appreciate the staff, our Members, and the witnesses for their indulgence. This has been important to our continuing basis of knowledge. We have a vote. I am afraid that the attendance would be

very poor if we tried to come back again, so we will adjourn, and

again, thank you for being here.

[Whereupon, at 12:20 p.m., the Committee was adjourned.]

(303)

Appendix:

ANSWERS TO POST-HEARING QUESTIONS

304

ANSWERS TO POST-HEARING QUESTIONS

Responses by Mark D. Levine, Division Director of the Environmental Energy Technology Division at Lawrence Berkeley Laboratory

Questions submitted by Representative Ralph M. Hall

Q1. In your testimony you state that the building sector needs targeted policies, including regulatory policies, to achieve mitigation goals because a large number

of barriers exist in the marketplace to deter investment in energy efficiency.

Please give me a few examples of these barriers and explain why you think regulatory policies are the way to overcome them.

A1. Up until appliance efficiency standards were put into place, the energy efficiency of appliances had not increased in years. Manufacturers were not aware of

ways to increase efficiency, because they had not explored them. As a result, consumers who may have wanted to obtain efficient appliances could generally not find

them in stores. And many customers who were not aware of energy efficiency and

thus had no information to know how much high energy-using appliances were costing them.

Appliance efficiency standards changed the situation by requiring all manufacturers to eliminate their most inefficient models. It ensured that the playing field was

level, in that all manufacturers had to eliminate inefficient models at the same levels. Later, when the standards brought more efficient models into the market, they

continued to have similar effects on all firms; if a more efficient appliance was more

expensive for one firm to manufacture it would be for other firms. (As it turned out,

the prices of more efficient appliances declined from their less efficient predecessors.)

There are many other examples of market barriers, which have been described

with references in the IPCC report. These include:

1. Traditional building design process, in which communications among architects, engineers, and contractors generally precludes execution of measures

for the whole buildings

2. Fragmented market structure: many small firms, fragmented knowledge,

limited R&D

3. High transaction costs to obtain reliable information about energy savings of

energy-efficient equipment (and often to find the equipment)

4. Misplaced incentives and administrative hurdles; e.g., landlords own building

but do not pay energy bills

5. Difficulty in obtaining loans because of small project size, high transaction

costs and perceived risk.

Questions submitted by Representative Gabrielle Giffords

Q1. As a Representative of a district from Southern Arizona, I am very interested

in the potential of solar energy and technologies to contribute to the reduction

of emissions of greenhouse gases. I believe that achieving energy independence

is the Apollo mission of our generation, and I am pleased that the IPCC Working Group III report acknowledges the significant role that solar energy and

technologies can play. Could you please address in detail how solar energy and

technologies can contribute reducing our dependence on fossil fuels both in

America and abroad? Please discuss solar technologies expected to be available

in 2030 as well.

A1. Solar energy was placed in the chapter of the IPCC report dealing with energy

supply. Thus, I was not part of the overall review of solar energy and this is not

my area of expertise.

However, I will share with you some of my views. I agree that there is a significant role for renewable energy. I believe this role will increase substantially with

time. Indeed, I am convinced that we need to have very significant increases in renewable energy in many forms in the time frame of one, two, and three decades if

we are to have a chance of addressing climate change. Right now, wind energy is

commercial in many locations. Unless there is a major breakthrough, it will probably be fifteen to twenty years before solar photovoltaic becomes a very large player.

However, thereafter it could be of enormous importance. My personal hope is that

we find a way through advanced science and technology to absorb sunlight into

woody crops and convert them into fuels in a highly efficient manner. High effiVerDate 11-MAY-2000 16:04 May 12, 2008 Jkt 032966 PO 00000 Frm 00078 Fmt 6601 Sfmt 6621 C:\WORKD\FULL07\020807\32966B.TXT SCIENCE1 PsN: SCIENCE1
305

ciency is the key; otherwise, very large amounts of land and water will be needed,

making the approach impractical.

Q2. As a follow up to my first question, could you address the potential for solar

energy and technologies in developing countries and the challenges they might

face in deployment of solar?

A2. Because developing countries have the least developed energy infrastructures

and will experience the greatest growth in energy demand in the coming decades,

the opportunities for renewable energy are great in these countries. A further advantage is that biomass can be gathered at low costs and renewable energy systems

can be assembled inexpensively because of low labor costs.

Major challenges are the cost of renewable energy systems—one cannot expect developing countries to pay more than the cost of fossil-based energy—as well as the

lack of skilled personnel (both technical and management) and often a very powerful

establishment deriving large sums of money from exploitation of fossil fuel.

In spite of these challenges, renewable energy will likely find a large role in developing countries over the coming decades.

Q3. To stabilize greenhouse gas concentrations to a level that will avoid the most

dangerous global warming, the costs, according to the Report, may vary from

a reduction of three percent GDP to an increase of one percent GDP. The reduction in GDP is deemed to be greater for more stringent stabilization targets.

Could you address the issue of cost? Do these numbers take into account the job

and economic growth that would result if we invest in a clean future? What role

does new and innovative technology play in the figures? Also, what are the costs

to the global economy if we do nothing to combat global warming? Can we even

truly quantify the costs to the global economy of increased global conflict and

decreased food supply, of less water resources and more risks to human health?

A3. As best as I can determine, these costs do assume that new and innovative

technology will cone into practice during the period of study. In the technical summary (page 41), it states ‘‘Baseline scenarios usually assume significant technological change and diffusion of new and advanced technologies. In mitigation scenarios there is additional technological change ‘induced’ through various policies and

measures.’’ However, it is not reported just how much improvement in technology

is to be expected in the different cases, so comparison is difficult.

I am not aware that the numbers take into account job and economic growth resulting from investment in clean energy technologies, as the aggregate models most

often assume that such investment is only productive if it lowers the cost of energy.

Most importantly, the numbers cited refer only to the economic costs of reducing

emissions of greenhouse gases; they do not include the benefits of avoiding the effects of global climate change. Apparently the integrated analyses of costs and benefits have not been put on a firm enough foundation for the IPCC to quote results

on this matter. In my view, you have put your finger on the problem: as you suggest

with your question, ‘‘we cannot even quantify the costs to the global economy of increased global conflict and decreased food supply, or less water resources and more

risks to human health.’’ As a result, IPCC can quote the economic costs of mitigation as estimated by economists but has a difficult time in its literature review of

finding quantification of the benefits of mitigation.

306

ANSWERS TO POST-HEARING QUESTIONS

Responses by William A. Pizer, Fellow at Resources for the Future and Senior Economist at the National Commission on Energy Policy

Questions submitted by Representative Ralph M. Hall

Q1. Some people that advocate for greenhouse gas regulations assert that only with

regulations will mitigation technology development occur, but in your testimony

you stated that there is little empirical evidence for how technological change

will respond to increased demand for emissions reductions. Why don’t we have

that evidence? What information or research is needed to better understand this

assertion?

A1. Most of what we know about the response of technological change to increased

demand for emission reductions comes from a limited number of studies. These

studies either look at the development of new technology—for example, scrubber

patents—in response to policy drivers, or improvements in energy efficiency in response to energy prices. (Popp, 2002; Newell, 1999). A separate line of analysis examines how technology costs fall with expanded production, but it is unclear whether expanded production is causing costs to fall, whether spending on research goes

along with production, or whether costs are the same, and expanded productions

creates more competition and lower prices to customers So ̈derholm and Klaasen

(2007).

Part of the problem is that we have very poor data on environmental expenditures, on research and development expenditures, and measures of environmental

performance. For example, the highly useful ‘‘Pollution Abatement Costs Expenditure Survey’’ collected by the Census Bureau was discontinued in 1994 for budgetary reasons (EPA, 2002). Additional spending on data collection concerning pollution control costs, environmental performance, and research spending, would greatly

enhance our understanding of how policy can drive technological improvement (see

NRC, 2004).

However, part of the problem is that we are inherently trying to drive the economy in new directions and we cannot completely know the responsiveness of new

technologies nor the eventual costs of mitigation efforts to new mitigation efforts.

Large scale capture and storage of emissions from coal-fired power plants, advanced

nuclear power, and geo-engineered biomass—these are but a few of the technologies

that a successful mitigation strategy will depend on. While more research can help

us understand the drivers of technological change in the past and likely responses

in the future, only pushing the economy in this direction can fully reveal the answers to how well these new technologies will work and at what cost.

That said, twenty years of economic research has revealed one thing—emphasized

in the IPCC report: The costs of any mitigation effort will be minimized by flexible

market-based policies that create broad demand for new technologies (see Box

SPM.3, IPCC WGIII, 2007). Efforts by the government to push particularly promising technologies can be helpful, but only as a complement to increased market demand.

Questions submitted by Representative Gabrielle Giffords

Q1. As a Representative of a district from Southern Arizona, I am very interested

in the potential of solar energy and technologies to contribute to the reduction

of emissions of greenhouse gases. I believe that achieving energy independence

is the Apollo mission of our generation, and I am pleased that the IPCC Working Group III report acknowledges the significant role that solar energy and

technologies can play. Could you please address in detail how solar energy and

technologies can contribute reducing our dependence on fossil fuels both in

America and abroad? Please discuss solar technologies expected to be available

in 2030 as well.

A1. Overall, solar technologies have a limited potential to displace fossil fuel use

in the near- and medium-term out to 2030. Chapter 4 of the IPCC WGIII (2007)

report includes an evaluation of the potential contributions of various low-carbon

technologies to energy supply in 2030. Section 4.4.3.3 addresses renewable technologies, including solar. It estimates that solar technologies can at maximum contribute 1–2 percent of the total electricity mix worldwide. This percentage is smaller

than for other renewable technologies such as hydro, wind, and electricity generated

from biomass. The primary reason for this is the projected high costs—between 6

cents–25 cents/kWh in 2030—for solar technologies relative to other low-carbon

307

technologies, as illustrated in Table 4.19: solar technologies are project to have the

highest costs, in terms of expense per emissions avoided, of any of the low-carbon

technologies discussed in the report.

There are two broad categories of solar technologies for electricity generation. The

first is photovoltaic (PV) cells, in which electricity is generated directly. The second

is thermal solar power—referred to as concentrating solar power (CSP) plants—in

which solar flux is collected, concentrated, and used to heat a working fluid which

in turn powers a conventional heat engine (e.g., a steam or gas turbine). PV cells

account for the vast majority of current solar generation, with current world peak

capacity estimated at 3000–5000 MW. This is located primarily in Germany, Japan,

and the United States. Most current installation is in response to subsidies such as

installation rebates or feed—in tariffs. About 80 percent of the PV module market

is occupied by traditional crystalline silicon cell technology. There are several other

technologies which have a small share of the commercial market or are in development which may become more competitive in the future. Thin film solar panels (8–

9 percent of the market) typically have lower conversion efficiencies than traditional

PV modules, but compete by being less expensive to manufacture. Among the other

technologies which are being explored are high efficiency alloy cells, photochemical

cells, polymer cells, and multi-layer cells. Most of these are not yet ready for commercialization. Currently, average levelized costs for grid-connected solar power are

17 cents–23 cents/kWh. (This compares with costs of 4–6 cents/kWh for coal- and

gas-fired generation.) The U.S. Climate Change Technology Program (CCTP) has a

stated goal of reducing these costs to 6 cents/kWh by 2030. A limiting factor for the

widespread deployment of solar PV technology could be the cost of silicon, particularly with competition from computing and electronics applications.

There are three main types of CSP plants, categorized by the technology used to

concentrate the solar flux: parabolic trough-shaped mirrors, heliostats—mirrors that

track the sun—that concentrate flux on a central tower, and parabolic dish-shaped

reflectors. The optimal sites for CSP plants are lower latitude locations that receive

high levels of direct sunlight, such as the American desert southwest. Currently,

there is far less CSP capacity installed—around 350 MWe—than PV capacity. It is

also far less dispersed, with almost all current capacity in California, and consists

primarily of parabolic troughs. However, there are several new projects underway

in 11 countries—including Spain, Israel, and the U.S.—that total over 1400 MW of

capacity, and use a wider variety of technologies. The U.S. CCTP has a goal of reducing near-term CSP costs to 9 cents–11 cents/kWh in the Southwest U.S. by 2010,

and eventually achieve costs of 3.5 cents–6.2 cents/kWh.

Finally, solar heating and lighting are non-central, distributed technologies that

provide the opportunity to reduce demand for centrally-generated energy and reduce

peak electricity loads. Passive space heating and cooling relies primarily on building

design, including orientation, shading, or placement of windows. Active systems capture solar heat for applications such as domestic hot water, heating of building

space, or swimming pool heating. Typical residential hot water systems can provide

40–70 percent of water heating requirements. Although around 1.2 million solar

water heating systems are installed in the U.S., the current rate of installation is

very low, around 8,000 units per year. Other portions of the world are adopting this

technology more rapidly, particularly China, which accounts for 80 percent of global

annual installations of solar hot water systems. Worldwide capacity of active solar

water heating is around 90 GWth, making solar heating the largest current solar

power source.

Q2. As a follow up to my first question, could you address the potential for solar

energy and technologies in developing countries and the challenges they might

face in deployment of solar?

A2. Solar power does have the potential to make a slightly larger impact in the developing world than in OECD countries. The WGIII report, section 4.4.3.3, projects

that while solar is likely to contribute a maximum of one percent of the electricity

supply in 2030 for OECD countries, it might amount to two percent in non-OECD

countries. Currently about 20 percent of new global PV capacity is being installed

in the developing world, primarily in areas that lack access to reliable grid electricity, and that expansion in these countries is rapid, around 30 percent annually.

A recent book (Barnes, 2007) includes case studies of how several countries, including Tunisia and Mexico, successfully used PV power as one part of a strategy to increase electrification in rural areas, relying on PV as a complementary strategy for

isolated users who could not access the grid. The high cost of PV power, however,

meant that these policies had to be heavily subsidized. Expansion of solar power in

developing countries will continue to rely on subsidies from governmental and nongovernmental organizations and policies.

308

Q3. To stabilize greenhouse gas concentrations to a level that will avoid the most

dangerous global warming, the costs, according to the Report, may vary from

a reduction of three percent GDP to an increase of one percent GDP. The reduction in GDP is deemed to be greater for more stringent stabilization targets.

Could you address the issue of cost? Do these numbers take into account the job

and economic growth that would result if we invest in a clean future? What role

does new and innovative technology play in the figures? Also, what are the costs

to the global economy of we do nothing to combat global warming? Can we even

truly quantify the costs to the global economy of increased global conflict and

decreased food supply, of less water resources and more risks to human health?

A3. As indicated in my written testimony, I tend to be wary of the low-end cost estimates contained in the IPCC report—suggesting a change in global GDP of between

+0.6 and -3 percent (Table SPM 4, IPCC WGIII, 2007). The estimates of gains in

global GDP hinge on two assumptions: (1) there are significant inefficiencies in the

existing economy; and (2) that government policies will fix these inefficiencies and

yield a gain. While certainly (1) is true, and (2) is likely true in some limited cases—

mainly surrounding energy efficiency and basic research—it seems unlikely that

both are true at a sufficiently large scale to make a difference in general cost studies.

The argument that job and economic growth can occur from an innovative and

clean future ignores the strong evidence that large volumes of clean energy will cost

more than ordinary energy. The best example is carbon capture and storage, whereby CO2 emissions from a coal-fired power plant are captured and stored underground-perhaps the most important technology we are counting on to mitigate climate change. The cost of capturing and storing CO2 will always be an additional

cost relative to operating a coal-fired power plant without capture and storage. In

this way, clean energy clearly costs more than ordinary energy.

This is not to say that investing in clean energy technologies now will not cut

costs in the future, nor give the U.S. some amount of a international competitive

advantage as future energy trends evolve towards cleaner sources. Rather, reducing

emissions will still cost real resources relative to not reducing emissions.

All of that said, I do believe that we can make significant reductions in emissions

at costs of less than one percent of global world product, and probably achieve the

most aggressive targets at three percent—assuming we can achieve global participation and enact efficient policies. In my mind, these are costs worth enduring.

There have been a variety of efforts to quantify the costs of inactions, summarized

in section 20.6 of the IPCC WGII (2007) report. These estimates tend to be less compelling than the cost studies because they are even more uncertain and hinge on

many subjective parameters—most notably the rate of ‘‘return’’ required on climate

change investments (also referred to as the discount rate). While Stern (2006) suggested damages equivalent to five percent of GDP, this was roundly criticized by

leading economists, primarily on the based on the discount rate assumptions

(Dasgupta, 2007; Nordhaus, 2007; Mendlesohn, 2007; Tol and Yohe, 2006).

References

Barnes, D.F., editor (2007). The Challenge of Rural Electrification: Strategies for Developing Countries, RFF Press: Washington, DC.

Dasgupta, Partha (2007). Comments on the Stern Review’s Economics of Climate

Change,’’ National Institute Economic Review, No. 199, 4–7.

EPA (2002). Letter from the Science Advisory Board to the Administrator, Importance of maintaining the Annual Pollution Abatement Cost and Expenditure

Survey. EPA–SAB–EEAC–COM–02–001

IPCC 2007, WGIII (2007). Climate Change 2007: Mitigation of Climate Change.

Cambridge: Cambridge University Press.

Mendelsohn, Robert (2007). A Critique of the Stern Report. Regulation 29:4.

Newell, Richard, Adam Jaffe, and Robert Stavins. 1999. The Induced Innovation Hypothesis and Energy-Saving Technological Change. The Quarterly Journal of

Economics 114 (3): 941–975.

Nordhaus, William (2007). A Review of the Stern Review on the Economics of Global

Warming. Journal of Economic Literature, forthcoming.

NRC (2004). Measuring Research and Development Expenditures in the U.S. Economy. Lawrence D. Brown, Thomas J. Plewes, and Marisa A. Gerstein, Editors,

Panel on Research and Development Statistics. Washington: National Research

Council.

309

Popp, David. 2002. Induced Innovation and Energy Prices. American Economic Review, 92(1): 160–180.

So ̈derholm Patrik and Ger Klaassen (2007), ‘‘Wind Power in Europe: A Simultaneous Innovation-Diffusion Model,’’ Environmental and Resource Economics, 36,

163–190.

Stern, Nicholas (2006). Stern Review on the Economics of Climate Change. Cambridge: Cambridge University Press.

Tol, Richard S.J. and Gary Yohe (2006). A review of the Stern Review. World Economics 7:4.

USCCTP, 2005, United States Climate Change Technology Program, http://

www.climatetechnology.gov/library/2005/tech-options/index.htm

310

ANSWERS TO POST-HEARING QUESTIONS

Responses by Steven E. Plotkin, Transportation Energy Analyst with the Center of

Transportation Research at the Argonne National Laboratory

Questions submitted by Representative Ralph M. Hall

Q1. In your testimony you state that technologies are available today to sharply reduce greenhouse gas emissions from the transport sector, but strong government

actions will be needed for those technologies to reach their full potential. Please

elaborate on this point: Specifically what technologies are you talking about? If

the technologies are available today, why is government action needed? What are

the major technical hurdles to making these technologies available? What are

the major (if any) societal or policy hurdles?

A1. Your first question concerns technologies available today to reduce greenhouse

gas emissions from the transport sector. In my testimony, I identified many of these

technologies. Some of the most promising technologies for light-duty vehicles are:

• Direct injection turbo-charged diesel engines. These engines represent

about half of the engines currently being sold in Europe, but few are sold in

the U.S. except in some light truck segments of the market. They can reduce

GHG emissions by about 20 percent compared to current gasoline engines.

• Direct injection gasoline engines, in both turbo-charged and naturally-aspirated form. Growing numbers of manufacturers (e.g., Audi,

Mazda, GM, Toyota, BMW) are offering these in the U.S., but presently only

in a few models. They should become more common in the future.

• Hybrid electric drivetrains ranging from simple stop-start systems to

full hybrids (e.g., Toyota’s Prius).

• 6, 7, and 8 speed automatic transmissions. Currently available only on

luxury models, they will migrate to the rest of the fleet.

• Improvements in aerodynamic performance. Sharp improvements have

recently been obtained in the crossover SUV segment of the market, and

there is significant opportunity across the fleet.

• Low rolling resistance tires. A key issue here is the difficulty of obtaining

these in the aftermarket; this was addressed recently by the National Academy of Sciences.

• Weight reduction through new materials and improved design. A 10

percent reduction in vehicle weight can translate into a 6–7 percent improvement in fuel economy if engine power is reduced to maintain the same performance.

• A wide variety of engine improvements, including more sophisticated

valve controls, engine friction reduction, variable air intake systems,

high pressure fuel injection systems, etc.

• Electric power steering and air conditioning.

• Higher efficiency accessories and measures to reduce vehicle heating

and cooling loads (e.g., window films to block solar input into the

cabin).

There are also many technologies currently in development that have an excellent

chance of technical and market success. Industry analysts believe, for example, that

gasoline engines will gradually gain the ability to use thermodynamic cycles that

are more efficient than the current Otto cycle. Plug-in hybrid vehicles may also play

an important role if battery development succeeds in providing less expensive and

more robust high-energy batteries. Biofuels, and in particular ethanol or other fuels

from cellulose, can play a significant role in replacing oil and reducing GHG emissions, but only if production costs can be reduced substantially. And eventually, hydrogen fuel cell vehicles may become commercially feasible, although there remain

important barriers in fuel cell cost, onboard hydrogen storage cost and capacity, and

the need to simultaneously develop a fuels infrastructure and vehicle production capacity.

Many of the above technologies will gain market share without government intervention, and some have already been helped by government economic incentives—

hybrids, for example, have been helped by generous federal tax credits. However,

in the absence of further government action, improvement in U.S. light duty vehicle

311

fuel economy may be quite disappointing. The primary reason for this prediction is

that U.S. consumers behave as if they do not place a high value on fuel economy

performance when purchasing new vehicles. Also, many vehicle purchasers apparently place a high value on vehicle features that directly conflict with fuel efficiency—particularly engine power and acceleration performance. In my testimony,

I noted that between 1987 and 2006 the U.S. new light duty vehicle fleet became

27 percent heavier and 30 percent faster in 0–60 mph acceleration time, and actually declined in fuel efficiency despite the introduction and widespread penetration

of a wide array of fuel efficiency technologies. Although high gasoline prices might

shift this trend somewhat in the future, I am relatively pessimistic that the market

alone will produce important gains in fleet fuel economy. Instead, I expect to see

many of the potential gains of these technologies used instead to improve vehicle

performance and increase other vehicle amenities, and I also expect that some of

the technologies will fail to gain nearly as much market share as would occur if fuel

economy were more highly valued.

The obvious question that arises from this narrative is, ‘‘Why should Congress act

to override market forces?’’ Historically, Congress has intervened in markets when

it determines that public values override private incentives and/or that markets are

operating inefficiently. For example, Congress enacted vehicle emission requirements when it determined that private decisions about the benefits of emission controls did not protect public health. And partly because many purchasers of appliances are home builders and rental building landlords who do not pay for the cost

of operating the appliances during their lifetime, Congress enacted legislation requiring the Department of Energy to set standards for appliance energy efficiency.

Although purchasers of light-duty vehicles and other energy-using equipment will

gain personal benefits from higher fuel efficiency, in the form of reduced energy

bills, they generally take no account of the societal costs of energy use—in particular, emissions of greenhouse gases and their impact on climate change, and the

energy security costs of oil use. Further, many analyses of the costs and benefits

of automobile fuel efficiency technologies have concluded that the net personal benefits—fuel savings minus higher vehicle costs—tend to be relatively small over a

range of fuel savings options. Combined with consumers’ tendency to value only the

first few years of fuel savings, this discourages manufacturers from taking market

risks in pushing fuel economy.

One obvious way Congress could address this issue is with new, more stringent

fuel economy standards. Automakers opposing new standards have argued that they

will greatly increase their market risks because consumers won’t want to purchase

the more efficient but more costly vehicles that will result. Consumers’ response to

the emission standards mentioned above—they were willing to continue to purchase

new vehicles with expensive emission controls despite industry fears—provides a

counter-argument. Using emission standards as an example, I would argue that new

fuel economy standards can be successful if the following criteria are met:

• Consumers must believe that the standards make sense, that is, that they

promote a real societal benefit (from decreased GHG emissions and lower oil

imports);

• The new standards must be technically achievable at reasonable cost and

must give automakers sufficient time to redesign their fleets; a starting point

for negotiations about ‘‘reasonable cost’’ might be the breakeven point between higher vehicle cost and lower fuel cost, with or without ‘‘externalities’’

accounted for in fuel cost; and

• The structure of the standards must be designed to spread the burden equitably among different automakers, to minimize market risk; the current

NHTSA design for new light truck standards (fuel economy targets based on

vehicle ‘‘footprint’’) is a good starting point for this.

Q2. In your testimony you state that the greatest potential impact on greenhouse gas

emission reduction in the transport sector lies in the developing world. If the

U.S. adopted many of the transport technologies and policies you discussed but

the developing world did not, would the U.S. actions it have a discernible influence on greenhouse gas levels? If so, what magnitude decrease could be

achieved? How would that number change if the developing world did participate?

A2. In your second question, you begin by saying that I claimed in my testimony

that ‘‘the greatest potential impact on greenhouse gas emission reduction in the

transport sector lies in the developing world.’’ I would like to repeat what I said in

my testimony:

312

A combination of careful urban planning and promotion of efficient public transport and walking and cycling can have a profound longer-term positive impact

on GHG emissions from urban transport as well as on the livability of cities.

Although the greatest impacts will be in the developing world whose cities and

transport systems are undergoing rapid transformation, important positive impacts can occur in the industrialized nations as well.

In other words, my statement about the differential potentials in the developed

and developing world referred only to the potential of urban planning and alternatives to private vehicles. The role of advanced technology may well be more important in the developed world than in the developing world. One possible exception

to this is the potential to introduce a gaseous vehicle fuel—the lack of an established gasoline refueling infrastructure in developing countries might offer some advantage here, although that might be overwhelmed by other considerations such as

availability of skilled construction labor.

In my view, it is unlikely that the U.S. would adopt multiple new transport technologies and policies without much of the rest of the world doing so also, because

the technologies are fungible and because much of the rest of the world is already

moving to promote improved efficiency in their light-duty fleets. In particular, Europe and Japan have much higher transport fuel prices than those in the U.S. but

also have new fuel economy standards that are considerably more stringent than

we have. And China, the developing nation with the fastest growing fleet of private

vehicles, also has enacted standards that are quite stringent for larger vehicles.

It is still possible to get a sense for what might happen if the U.S., or the OECD

nations, acted alone or together with the rest of the world in curbing transport GHG

emissions by examining the current and expected shares of transport emissions and

energy use in these regions. In the year 2002, the U.S. and Canada accounted for

about 39 percent of total world transport energy use and GHG emissions, and the

OECD nations (which include the U.S. and Canada) accounted for 68 percent. By

2030, the International Energy Agency’s 2004 International Energy Outlook expected the U.S. and Canada share to decline to 32 percent, and that of the OECD

nations to decline to about 55 percent. Consequently, if the U.S. acted alone, it

would essentially leave about two-thirds of world transport emissions untouched; if

the developed nations of the OECD acted alone, without the developing nations and

the economies of the former USSR that would leave about 40 percent of the world

transport emissions untouched.

In the IPCC analysis, which focused on light-duty vehicles, about half of the 2030

reductions in GHG emissions (from a ‘‘business as usual’’ case) achieved by an ‘‘efficiency strategy’’ occurred in the United States, and about 70 percent occurred in the

OECD countries. The U.S.’s large share of reductions results from two factors—the

very high driving rates for U.S. vehicles (which improves the economic viability of

new technologies), and the low expected fuel economy levels for the U.S. fleet in the

‘‘business as usual’’ case, which leaves more room for improvement. In other words,

for this one analysis, the effect of the U.S. ‘‘going it alone’’ would mean that the

total GHG emissions reductions achieved worldwide for the light-duty vehicle sector

would be cut in half compared to a worldwide strategy.

Questions submitted by Representative Gabrielle Giffords

Q1. As a Representative of a district from Southern Arizona, I am very interested

in the potential of solar energy and technologies to contribute to the reduction

of emissions of greenhouse gases. I believe that achieving energy independence

is the Apollo mission of our generation, and I am pleased that the IPCC Working Group III report acknowledges the significant role that solar energy and

technologies can play. Could you please address in detail how solar energy and

technologies can contribute reducing our dependence on fossil fuels both in

America and abroad? Please discuss solar technologies expected to be available

in 2030 as well.

Q2. As a follow up to my first question, could you address the potential for solar

energy and technologies in developing countries and the challenges they might

face in deployment of solar?

Q3. To stabilize greenhouse gas concentrations to a level that will avoid the most

dangerous global warming, the costs, according to the Report, may vary from

a reduction of three percent GDP to an increase of one percent GDP. The reduction in GDP is deemed to be greater for more stringent stabilization targets.

Could you address the issue of cost? Do these numbers take into account the job

and economic growth that would result if we invest in a clean future? What role

313

does new and innovative technology play in the figures? Also, what are the costs

to the global economy of we do nothing to combat global warming? Can we even

truly quantify the costs to the global economy of increased global conflict and

decreased food supply, of less water resources and more risks to human health?

A1, 2, 3. Congresswoman Giffords’ questions focus on solar energy and broadly on

stability costs and benefits. I have no expertise to deal with her first two questions,

about the role of solar energy, and only limited expertise in dealing with the third

question, about costs. I will only make a few comments on this last question.

The first part of the question asks whether the mitigation cost numbers take into

account the job and economic growth that would result if we invest in a clean future. Although some mitigation analyses identified in the literature—particularly

those that use sophisticated economic models—will capture such effects to some extent, the analysis used in the transport sector did not use an economic model and

would not have captured economic growth and jobs impacts.

The question then asks about the role of new and innovative technology in the

cost figures. The analyses and models used to quantify the costs and GHG emissions

reductions of various mitigation strategies have limited ability to capture the role

of new and innovative technologies, especially over longer time frames. Those technologies that have begun development generally have highly uncertain future costs

and performance, and their likely future market penetration also is highly uncertain. The instigation of incentives to reduce emissions eventually will yield new but

as yet unidentified technologies, but no analysis or model can properly account for

these technologies. At best, analyses and models can assume rates of improvement

in the energy efficiency of core services and industries, based on historical experience.

A second part of the question asks whether we can quantify the costs to the global

economy if we do nothing to combat global warming. The mitigation report did not

address this issue, and the issue lies outside my area of expertise.

314

ANSWERS TO POST-HEARING QUESTIONS

Responses by Roger A. Pielke, Jr., Professor of Environmental Studies Program at

the University of Colorado and Director of the Center for Science and Technological Policy Research

Questions submitted by Representative Gabrielle Giffords

Q1. As a Representative of a district from Southern Arizona, I am very interested

in the potential of solar energy and technologies to contribute to the reduction

of emissions of greenhouse gases. I believe that achieving energy independence

is the Apollo mission of our generation, and I am pleased that the IPCC Working Group III report acknowledges the significant role that solar energy and

technologies can play. Could you please address in detail how solar energy and

technologies can contribute reducing our dependence on fossil fuels both in

America and abroad? Please discuss solar technologies expected to be available

in 2030 as well.

A1. I am not an expert in solar energy technology.

Q2. As a follow up to my first question, could you address the potential for solar

energy and technologies in developing countries and the challenges they might

face in deployment of solar?

A2. As above in #1.

Q3. To stabilize greenhouse gas concentrations to a level that will avoid the most

dangerous global warming, the costs, according to the Report, may vary from

a reduction of three percent GDP to an increase of one percent GDP. The reduction in GDP is deemed to be greater for more stringent stabilization targets.

Could you address the issue of cost? Do these numbers take into account the job

and economic growth that would result if we invest in a clean future? What role

does new and innovative technology play in the figures? Also, what are the costs

to the global economy of we do nothing to combat global warming? Can we even

truly quantify the costs to the global economy of increased global conflict and

decreased food supply, of less water resources and more risks to human health?

A3. The IPCC estimates for the future costs of stabilization depend a great deal

upon assumptions used in the so-called ‘‘Integrated Assessment’’ models that are

used as the basis for the scenarios employed by the IPCC (the ‘‘SRES scenarios).

Each of these scenarios assumes that spontaneous technological innovation (i.e.,

without implementation of climate-related energy policies) will account for an enormous reduction in future emissions, as compared to scenarios with no technological

innovation (note that the IPCC discusses this on pp. 218–221 of Chapter 3 in its

Working Group III report, see especially Figure 3.33 which shows this reduction).

One question that has received insufficient attention is whether or not the assumptions by the IPCC of such automatic emissions reductions via spontaneous

technological innovation are in fact sound. If such technological innovation does indeed occur spontaneously, then the marginal costs of stabilization of greenhouse

gases will be much smaller than otherwise. Rather than assume such technological

innovation, it may be appropriate for Congress to consider ensuring that it occurs

through an aggressive investment strategy that has benefits not simply for climate,

but for air pollution, reduced reliance on foreign energy sources, job creation, and

economic competitiveness.