United States

Department of

Agriculture

Forest Service

Pacific Northwest

Research Station

General Technical

Report

PNW-GTR-706

March 2007 U S

Bringing Climate Change Into Natural Resource Management PNW-GTR-706 

Bringing Climate Change Into 

Natural Resource Management

Proceedings of a Workshop

U.S. Department of Agriculture

Pacific Northwest Research Station

333 S.W. First Avenue

P.O. Box 3890

Portland, OR 97208-3890

Official Business

Penalty for Private Use, $300

BCCNRM_Cover.indd 1 2/2/07 12:04:51 PM
Bringing Climate Change Into 

Natural Resource Management

Proceedings of a Workshop

June 28-30, 2005

Portland, Oregon 

 Technical Coordinators:

 Linda Joyce, Richard Haynes, 

 Rachel White, and R. James Barbour

Olympic National Park
Abstract

Joyce, Linda; Haynes, Richard; White, Rachel; Barbour, R. James, tech. 

coords. 2006. Bringing climate change into natural resource management: 

proceedings. Gen. Tech. Rep. PNW-GTR-706. Portland, OR: U.S. 

Department of Agriculture, Forest Service, Pacific Northwest Research 

Station. 150 p. 

These are the proceedings of the 2005 workshop titled implications 

of bringing climate into natural resource management in the Western 

United States. This workshop was an attempt to further the dialogue 

among scientists, land managers, landowners, interested stakeholders and 

the public about how individuals are addressing climate change in natural 

resource management. Discussions illustrated the complexity of global 

climate change and the need for managers to consider how the impacts 

of climate change will unfold across regional and local landscapes. The 

workshop offered examples of how managers are already responding to 

those aspects of the global climate change that they can see or perceive. 

While no comprehensive solutions emerged, there was an appreciation 

that policy complexity may exceed the science complexity but that 

eventually the accumulation of local actions will shape the future. 

Keywords: Climate change, forest and range management.
Contents

Introduction

Introduction..............................................................................................................................................................1

Rachel White and Jamie Barbour

Agenda

Climate Variability and Change as a Backdrop for Western Resource Management ............................................5

Kelly T. Redmond

Terrestrial and Aquatic Natural Ecosystems: Potential Responses to Global Climate Change.............................41

Hermann Gucinski

Social and Economic Issues of Global Climate Change in the Western United States.........................................67

Randall S. Rosenberger

The Challenges of Bringing Climate into Natural Resource Management: A Synthesis .......................................91

Linda Joyce and Richard Haynes

The Roundtable Session .....................................................................................................................................109

Rachel White and Jamie Barbour

Extended Abstracts

The Potential for Widespread, Threshold Dieback of Forests in North America 

 Under Rapid Global Warming ......................................................................................................................117

R.P. Neilson, J.M. Lenihan, D. Bachelet, R.J. Drapek, D. Price, D. Scott

Predicting Climate-Induced Range Shifts for Mammals: How Good are the Models? ........................................123

Joshua J. Lawler, Denis White, Ronald P. Neilson, Andrew R. Blaustein

Community Response to Climate Change and Forest Disturbance....................................................................127

Courtney G. Flint

Climate Change and Community Resilience: A Knowledge Management Exercise ..........................................133

Trista Patterson
Poster Persentation Abstracts

Rising Atmospheric CO2 and Carbon Sequestration in Forests ..........................................................................141

Beedlow, P. 

Invasive Plant Expansion into Biogeoclimatic Envelopes under Current Climate and Global Climate 

 Change Scenarios in Alaska.........................................................................................................................141

Bella, Elizabeth

Modeling Impacts On The Levels Of Sustainable Resources From Increased Wildfire Acres 

 Associated With Potential Climate Changes ................................................................................................142

Chew, J.; Bollenbacher, B.; and C. Stalling

Natural Resource Managers Respond to Climate Change: A Look at Actions, Challenges, 

 and Trends....................................................................................................................................................142

Laskowski, M. and L.A. Joyce

The Influence of El Niño-related Sea-Surface Temperature Gradients (Trans-Niño Index) 

 on Upper Klamath Basin Stream Discharge.................................................................................................143 

Kennedy, Adam M. 

Knowledge Management for Climate Change in Northern Renewable-Resource Based Communities .............143

L. Kruger and T. Patterson

Predicting Climate-induced Range Shifts for Mammals: How Good are the Models? ........................................144

Lawler, J.; White, D.; Neilson, R.; and A. Blaustein

Impact of Climate Change on Landscape-level Fire Severity Ratings in the North Okanagan, 

 British Columbia, Canada.............................................................................................................................144

Nitschke, Craig and J. L. Innes

Linking Climate to Multi-purpose Reservoir Management in the Gunnison Basin ..............................................145

Ray, Andrea J. 

Speaker List ........................................................................147

Metric-English Equivalents................................................150


1Science Writer-Editor, USDA Forest Service, Pacific Northwest Research Station, P.O. Box 3890, Portland, OR 97208. Email: rachelwhite@fs.fed.us

2Program Manager, USDA Forest Service, Pacific Northwest Research Station, P.O. Box 3890, Portland, OR 97208. Email: jbarbour01@fs.fed.us

Rachel White1 and Jamie Barbour 2

— Introduction — 

Tom Iraci, USDA Forest Service

Erik Ackerson, EarthDesign, Ink

Tom Iraci, USDA Forest Service


A few unusually big tropical storms and hurricanes don’t “prove” 

global warming is happening. But the hurricane season of 2005, which 

included monsters Katrina and Rita, has at least pointed anecdotally 

toward the predictions of extreme weather that have accompanied most 

climate change scenarios. Scientists around the globe have been making 

these predictions and warnings about climate change for decades. 

The Intergovernmental Panel on Climate Change (IPCC), created in 

1988 by the United Nations, has issued strong statements about the 

changing climate and has written a comprehensive study of it and its 

potential effects (IPCC 2001). This team, which includes more than 

2000 scientists from 100 countries, represents the largest scientific 

collaboration in history. Public understanding of the issue varies. Many 

in the science community recognize climate change as a serious matter 

where the consequences are likely to continue for many centuries. In 

the land management community, some managers are starting to adapt 

management strategies for changing climatic conditions. 

The issue of global climate change is highly complex and the spatial 

and temporal natures of its impacts are highly uncertain. First, there is the 

scientific complexity of a global issue and its relation to specific localities 

relevant to land managers. Second, there is uncertainty about the speed 

and extent of its occurrence that complicates human responses. Third, 

there is great market and policy complexity since it is an issue that crosses 

national and ownership boundaries.

It is the manager’s response to the complicated aspects of the global 

climate change issue that motivated this workshop. How are they adapting 

their local actions and how do these actions contribute to mitigation of 

either climate change or its impacts? The workshop was an attempt to 

have a dialogue on the kinds of information (mostly at the local scale) 

managers need to address climate change in natural resource management. 

Through civic engagement, we can help increase the understanding both 

of the complexity of the issue and ways in which land managers can 

modify their actions to increase the certainty of outcomes in the face of 

changing climate. 

Integrating (let alone locating) scientific information is sometimes a task easier said than 

done. Recognizing this, in 2003 then Pacific Northwest Research Station Director Tom Mills 

launched the Focused Science Delivery (FSD) program as one way to help address what he 

saw as a flaw in the way that scientific information is adopted and used by policy makers 

and natural resource managers. The purpose of the FSD program is to conduct syntheses 

of existing scientific information, perform analyses that will make this information more 

useful to natural resource practitioners, identify gaps in current knowledge, frame problems 

so that original research is more efficient, and deliver information in innovative ways 

that will quickly bring it into use. The “Bringing Climate Change into Natural Resource 

Management” conference is an example of a recent FSD effort—one intended to create a 

venue for scientists and managers to explore together problems and potential strategies for 

bringing climate change into natural resource planning.

Many in the science 

community recognize 

climate change as a 

serious matter where the 

consequences are likely to 

continue for many centuries.

It is the manager’s response 

to the complicated aspects 

of the global climate change 

issue that motivated this 

workshop. 


The Workshop

In late June 2005, the USDA Forest Service (Pacific Northwest 

and Rocky Mountain Research Stations) and the Western Forestry and 

Conservation Association hosted a conference in Portland, Oregon on 

climate change. The conference presented some of the latest developments 

in climate change research related to natural resource management, 

covering topics like the climate of the West, fire dynamics in the future, 

western water resources, invasive plants, western bark beetle management, 

native vegetation responses to increasing carbon dioxide, and carbon 

sequestration. Panels explored western ecological responses to climate 

change, socioeconomic impacts, and what the future may hold for natural 

resource management under climate change. The presentations and panels 

provided excellent coverage of information, using the traditional “lecturestyle” conference format, and successfully raised awareness on some very 

timely topics. 

These proceedings are not the usual workshop documentation. Instead 

they contain four essays (three topical and one synthetic), the results of a 

series of roundtable discussions, and selected papers including several that 

are context setting. 

References

Intergovernmental Panel on Climate Change [IPCC]. 2001. Third IPCC 

assessment report: summary for policymakers. Geneva: Switzerland: IPCC 

Secretariat.

The conference presented 

some of the latest 

developments in climate 

change research related 

to natural resource 

management...



Climate Variability and Change as a Backdrop 

for Western Resource Management 

Kelly T. Redmond1

1Regional Climatologist/Deputy Director at Western Regional Climate Center, Desert Research Institute, 2215 Raggio Parkway, Reno, NV 89512-1095. 

Email: Kelly.redmond@dri.edu

— Agenda —

Tom Iraci, USDA Forest Service

Mark Reid, USDA Forest Service


Abstract

Climate and its variations constitute a dominant driver of natural 

systems. Effective management of the natural resources of the West 

requires knowledge of the spatial and temporal characteristics of climate, 

and of ways of utilizing that knowledge. The topographic diversity of 

the West leads to similar diversity and structure in its climates. Climate 

varies naturally for many reasons, encompassing external forcings and 

internal dynamics. Human activities are increasingly an additional source 

of spatial and temporal variability in climate, at global, regional and local 

scales. Greenhouse gasses and aerosols are two well-known factors, but 

there are many others as well. The response of environmental systems 

varies from simple and straightforward to exceedingly complex. The 

Western United States has been warming during the past three decades, 

much more than the Eastern states, and more in winter than in summer. 

Evidence for this comes from many independent sources. Precipitation 

is much more variable and there are no discernible overall trends in this 

element for the West as a whole. In broad measure these findings do not 

appear to contradict theoretical expectations. There is more confidence 

in temperature than in precipitation projections. Temperature increases, 

by themselves, have significant hydrological implications. Snow and 

snow melt are critical factors in western water supplies, and there are 

numerous indications of reductions in snow over the past 2-3 decades. 

The U.S. vulnerability of snow-driven hydrology to temperature increase 

is much greater in the mountainous Western states, and greatest along 

the west coast. These changes, and apparent connections to temperature, 

may require societal adjustments and therefore must be more fully 

characterized and understood. Several teleconnections to global climate 

exist, the most important being to El Niño, La Niña, and the Southern 

Oscillation (ENSO), and furnish an important source of interannual 

variability. Persistent drought episodes in the region are linked to tropical 

ocean conditions. The region is monitored unevenly, favoring lower 

elevations and population concentrations. Conditions where important 

resources are located are not as well monitored. Many opportunities exist 

for improved monitoring, but they require persistence, dedication, and a 

strong commitment to coordination. Methods and structures are present 

to provide access to the large volume of data and information that does 

exist, but need further improvement. Variations and trends in climate are 

taking place in a region where many other factors are likewise changing, 

especially demographics, lifestyles, attitudes, and economics, and these 

relationships must be understood and accommodated in making good 

management decisions. 

Keywords: Climate, variability, monitoring, temperature, precipitation, 

snowpack, data.


Introduction

Climate and its variations constitute an important driver of natural 

systems. This discussion is predicated on the assumption that improved 

awareness and utilization of climate knowledge will result in improved 

management of natural resources. Variability is an inherent property 

of climate, driven by constant fluctuations in flows of energy and mass 

throughout the system. These flows are seldom in full equilibrium across 

important system interfaces, and fluctuations in stored energy and mass 

make up the difference. External drivers and internal dynamics operate 

on many different time scales, from microseconds to eons, to produce the 

variations we observe. The mixture of climate drivers is itself not constant, 

and in recent decades factors of human origin have increasingly been 

adding a new source of climate variability. No matter what humans do, or 

how much role they play in affecting climate, the existing natural sources 

of climate variability will continue to exert their influences as before. 

(In this article, the term “variability” is generally intended to connote 

temporal rather than spatial variability.) Fluctuation has been a constant 

accompaniment to climate and this is not going to stop.

Through their technology and their sheer numbers, humans have 

acquired the ability to modify climate in many ways. Most of these 

ways involve the manner in which energy moves through the system, 

particularly in the form of radiation. Others involve the microphysical 

processes that produce precipitation, operating at tiny scales. Still others 

involve chemical and biological pathways, and the vegetation that covers 

most landscapes. Climate changes associated with humans involve more 

than just greenhouse gasses, although the latter receive much of our 

current attention. 

Examples of these human modes of influence include 

greenhouse gasses (carbon dioxide, ozone, nitrous oxide, methane, 

chlorofluorocarbons, water vapor) and aerosols (particles suspended in 

a gas: dust from volcanoes, lakebeds, and disturbed soil; soot, ash, and 

pollution; and gasses transformed through photochemistry to particles), 

all of which affect the flow of radiant energy through air. Changes in 

land surface properties all affect the absorption and emission of solar and 

infrared energy, the partitioning of energy transfer between sensible heat 

and evaporation, the speed of the wind, and the flow of energy to/from 

the substrate. These properties include reflectivity or “albedo,” wetland 

fraction, permeability to water, presence or absence of reservoirs, and 

substrate properties, brought about by activities such as deforestation, 

irrigation, agricultural practices, paving, or other kinds of development. 

Cloud droplets and ice crystals form around small nuclei, and recent 

findings indicate that changes in atmospheric particle concentration 

can greatly alter cloud properties and reduce precipitation efficiency 

and amount, and affect its type (rain or snow). Changes in atmospheric 

CO2, ozone and other gaseous and aerosol constituents have direct but 

differential physiological effects on vegetation, species competitiveness, 

amount and quality of light, which in turn affect soil moisture and 

recharge budgets, plant species composition and community properties. 

Through their technology 

and their sheer numbers, 

humans have acquired the 

ability to modify climate in 

many ways. 


All of the above mechanisms are primary, acting as physical drivers 

to modify climate. Secondary mechanisms, acting in response to climate, 

are even more diverse, and include hydrological and biological responses 

to the original source of climate variation, and feedback effects that act 

to amplify or dampen climatic responses. Although certain processes and 

constituents dominate the discussion, climate change is not a single-issue 

problem and has numerous dimensions, many interacting synergistically.

In some cases the effects of particular changes act on climate to 

reinforce the original effect (positive feedback) or to dampen the original 

effect (negative feedback). A multitude of both kinds of feedback 

processes are at work, although ultimately it is negative feedbacks that 

keep our climate from wildly fluctuating from one time period to the next 

or running off to some extreme equilibrium state (Rial et al. 2004).

Observed Variability and Trends

The West is a land of juxtapositions and sharp contrasts, a salient 

characteristic of its climate and of other attributes. Basic climate categories 

can change over short distances, as does precipitation seasonality, annual 

amount, and phase (rain/snow). Temporal variability properties can vary 

over short spatial distances (Redmond 2003). Elevation plays a key role, 

and mountain ranges greatly modify and sometimes cause their own 

weather. Mountain time series of climatic elements can be very different 

from those in the adjoining valleys. Large scale “teleconnections” with 

other parts of the globe lead to spatially different responses in reaction 

to far-away phenomena such as El Niño and La Niña. Much of western 

hydrology is snowmelt driven (2/3 to 3/4 by most accounts), so that winter 

conditions are extremely important to the annual water budget of the 

entire region. Precipitation and streamflow show much greater relative 

(normalized) interannual variability in the Southwest than the Northwest 

(Cayan et al. 2003), with the greatest variability seen along the West 

Coast (Andrews et al. 2004).

For purposes here we focus primarily on the 11 westernmost 

continental (mountain) states, although many comments apply to Alaska 

and Hawaii as well. The 11 states occupy 1.20 million square miles, 38 

percent of the lower 48. With Alaska/Hawaii, the 1.87 million square 

mile total is 49 percent of the U.S. 50-state area. The 11 conterminous 

states show significant and different variability properties in temperature 

compared with precipitation. Winter (October-March) temperatures from 

1895-96 through 2004-05 are shown in figure 1 for the entire region. 

They show considerable winter-to-winter variability, and in later decades 

exhibit a trend that began in the late 1970s/early 1980s. Annual (calendar 

year) temperatures are shown in figure 2 from 1895-2004. The rising 

trend over the past 30 years is again evident. 

Although attribution is not a main goal here, shown in figure 3 are 

a series of temperature projections from 6 models and 2 greenhouse gas 

emission scenarios compiled by Dettinger (2004), for a location between 

Reno, Nevada and Susanville, California (representative of most of the 

West). These show that a general rise out of the inherent variability 

Much of western hydrology 

is snowmelt driven (2/3 to 

3

/4 by most accounts), so 

that winter conditions are 

extremely important to the 

annual water budget of the 

entire region.


End year

1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010

32

33

34

35

36

37

38

39

40

41

42

43

Western Regional 

Climate Center

Degrees F

individual winters

11-year running mean

Figure 1—Mean cold-season temperature (October-March) for the 11 westernmost continental states, 

area-weighted from divisional data, 1895-2006. Data source: National Climatic Data Center.

Year

1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010

47

48

49

50

51

52

53

Western Regional

 Climate Center

Degrees F

individual winters

11-year running mean

Figure 2—Mean annual calendar-year temperature for the 11 westernmost continental states, areaweighted from divisional data, 1895-2005. Data source: National Climatic Data Center.

should have begun sometime around 1980, and also show fairly close 

agreement between models during the first half of the 21st Century. There 

is a strong suggestion in these figures that climate change has already been 

underway in the Western states, escaping our notice for the last 25 years 

until this signal began to rise above the background variability. Seasonal 

temperature trends are shown in figure 4. Winter and spring have the 

strongest trends in later years.

By contrast, western winter precipitation since 1895 has rather 

different properties, as shown in figure 5. There is little trend, but 

great variability, and furthermore there is a change in the properties of 

variability after the mid 1970s. Water-year precipitation from 1895-

96 through 2004-05 is shown in figure 6. After a period of relatively 

There is a strong suggestion 

in these figures that climate 

change has already been 

underway in the western 

states, escaping our notice 

for the last 25 years...
1

0

Year

1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010

71706968676665

Summer

End Year

1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010

383736353433323130292827262524

Winter

Year

1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010

54535251504948474645444342

Spring

Year

1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010

545352515049484746

Autumn

individual winters

11-year running mean

Degrees F

Degrees F Degrees F

Degrees F

Western Regional Climate Center

Figure 3—Mean seasonal temperature for the 11 westernmost continental states, area-weighted from divisional data, Jan 1895 through Mar 2006. Upper left: Dec-Jan-Feb. Upper right: Mar-Apr-May. Lower left: Jun-Jul-Aug. Lower right: Sep-Oct-Nov. Data source: National Climatic Data Center.
11

Year

1900 1920 1940 1960 1980 2000 2020

-2

0

4

6

8

Degrees C

2040 2060 2080 2100

2

A2 Emissions

B2 Emissions

BAU Emissions

Projected changes in annual temperature, Northern California

Western Regional 

Climate Center

Figure 4—Simulated and projected temperature changes, between Reno, Nevada and Susanville, 

California, 1900-2100, from six climate models using three emissions scenarios, compared with baseline 

case. (1 C = 1.8 F). From Dettinger (2004). 

End Year

1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010

4

5

6

7

8

9

10

11

12

13

14

15

Western Regional

 Climate Center

Precipitation (inches)

individual winters

11-year running mean

Figure 5—Total cold-season precipitation (October-March) for the 11 westernmost continental states, 

area-weighted from divisional data, 1895-2006. Data source: National Climatic Data Center.

little variability for several prior decades, the West has seen pronounced 

variability in precipitation since the standout drought winter of 1976-77, 

followed a few years later by the wettest winter on record in 1982-83. Not 

only has there been significant variation from year to year, but also over 

the past 30 years the West has experienced several extended periods that 

were wet (early 1980s), dry (1987-1994 excepting 1992-93), wet again 

(mid to late 1990s), and dry again with very severe drought from 1999-

2004 (not known at this writing if 2004-05 marked the end). A portion 

of this variability appears related to the “1976 shift” in Pacific climate 

(Ebbesmeyer et al. 1991; Trenberth and Hurrell 1994) and the changed 

frequency of El Niño and La Niña, but likely not entirely so. 

The precipitation projections from the same set of models employed 

by Dettinger (2004) are shown in figure 7. Collectively they show 
12

little trend, and exhibit more scatter among themselves later in the 21st

Century, with also a suggestion of greater interannual and multi-year 

variability. 

Global average effects of climate change will not be identical at each 

and every location.

The general expectation is that Earth’s climate will warm from 

greenhouse gasses, and that the hydrological cycle will speed up (more 

evaporation, more rain). However, the spatial and seasonal distribution 

of any such changes will vary regionally and locally. This is especially 

the case for precipitation. In the West such changes may also vary with 

elevation, because the ways in which mountains enhance precipitation are 

dependent on temperature, moisture, vertical stability, and trajectory.

In addition, the projections shown in figures 4 and 7 show more 

commonality for temperature than for precipitation, with tighter 

clustering among models and scenarios. At this point there is much 

more confidence in projections of temperature than in projections of 

precipitation. The question of whether precipitation will increase or 

decrease or stay the same, or in what seasons or locations or elevations, 

is not likely to be answered definitively very soon. Our response and 

adaptation mechanisms should be prepared to accept this state of affairs.

In terms of regional differences, the era since the turn of the new 

Millennium has brought warm conditions much more frequently to the 

West. Figure 8 shows the 72-month anomaly from the period mean, for 

the interval January-December 2000-2005. These and other studies have 

shown that most of the warming seen in the United States has been in 

the 11 Western states and the northern High Plains, with relatively little 

warming seen in the Eastern and particularly Southeastern United States 

(fig. 8). Whatever the reason, warming of the West appears to be a fact of 

life.

End year

1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010

12

13

14

15

16

17

18

19

20

21

22

23

24

Western Regional

 Climate Center

Precipitation (inches)

individual winters

11-year running mean

Figure 6—Mean annual water-year precipitation (October-September) for the 11 westernmost continental 

states, area-weighted from divisional data, 1895-2005. Data source: National Climatic Data Center.

The general expectation 

is that Earth’s climate will 

warm from greenhouse 

gasses, and that the 

hydrological cycle will 

speed up (more evaporation, 

more rain).

Whatever the reason, 

warming of the West 

appears to be a fact of life.
13

For purposes of forecast interpretation, the NOAA Climate Prediction 

Center has computed successive trends for each climate division in the 

United States from 1941-1998, and for all 3-month seasons, with a 

hinge point at 1966 (CPC 2005c). The trend after this hinge (1966-

1998) shows similar patterns of warming to those in figure 8, much 

more accentuated in winter than in summer. Cayan et al. (2001) used 

phenological evidence from a network of lilacs and honeysuckles [shows] 

that bloom dates have been occurring earlier each year for the last 

several decades. In the same paper they also presented further evidence 

of an earlier onset to spring in the West in the timing of the snowmelt 

“pulse.” Spring runoff in snow-fed basins typically begins in a sudden 

burst that can usually be identified to within a day or two. Over the past 

3-5 decades dates of this spring pulse have been occurring earlier by 1-

4 weeks in the Western contiguous United States, Canada, and Alaska 

(Stewart et al. 2005). Conversion of the bloom and spring pulse dates into 

temperature terms shows that they agree with thermometer records for 

the late winter and spring that precede these events (Cayan et al. 2001). 

This correspondence has given us more confidence in all of the separate 

time series, especially those for temperatures that are based strictly on 

thermometers. 

Western snowpack is critical to summer streamflow, and normally 

peaks between March 1 in the southern West and May 1 in the northern 

West; April 1 is commonly used as a west-wide date of maximum 

snowpack. Mote (2003a, 2003b) used data from the Natural Resources 

Conservation Service (NRCS) Snotel network and its predecessor, the 

snow course network, to show that the snowpack on this date has shown a 

recent decline over most of the West. Later studies, Mote et al. (2005) and 

Mote (submitted), expanded to the remainder of the West and showed 

a similar result, except in the southern portions. Subsequent diagnosis 

(Hamlet et al. 2005) has shown that both temperature and precipitation 

trends in winter have contributed to the observed trends in April 1 snow 

water equivalent (SWE, the water residing in the snowpack if melted). 

Year

1900 1920 1940 1960 1980 2000 2020

 0

100

150

200

Percentage of 1951–1980 norm

2040 2060 2080 2100

 50

Projected changes in annual precipitation, Northern California

 -50

 -100

Figure 7—Simulated and projected precipitation changes, expressed as percentages, between Reno, Nevada 

and Susanville, California, 1900-2100, from six climate models using three emissions scenarios, compared 

with baseline case. From Dettinger (2004). 

...phenological evidence 

from a network of lilacs 

and honeysuckles [shows] 

that bloom dates have been 

occurring earlier each year 

for the last several decades. 
14

In almost every location, temperature trends are acting to reduce late 

season snowpack, but in some locations, notably the southern Sierra 

Nevada, the effects from upward precipitation trends on snowpack 

(possibly from increased El Niño frequency) have overcome the effects of 

trends toward higher temperatures on snowpack. 

The factors that control the properties of the spring snowmelt pulse 

can be deduced with the help of hourly streamflow data (Lundquist 

and Cayan 2002, Lundquist and Dettinger 2005). Lundquist and 

Dettinger (2004) examine the very interesting issue of the details of 

how the spring snowmelt pulse forms, and its synchroneity at different 

altitudes. Surprisingly, this does not always appear to steadily march up 

the elevation gradient as spring warms up, and varies considerably from 

one year to another. In the Western states late winter and early spring 

have shown the greatest rate of warming during the year (CPC 2005c). 

The ratio of early summer runoff to the annual total began to decrease in 

the latter quarter of the 20th Century (Aguado et al. 1992, Dettinger and 

Cayan 1995, Roos 1991). Subsequent studies (Dettinger 2005; Stewart et 

al. 2004, 2005) have shown that earlier spring pulses and runoff fractions 

are occurring from Mexico to Alaska. Regonda et al. (2005) show a variety 

of interlinked trends stemming from warming that are consistent with 

many of the foregoing results, and in aggregate constituting a significant 

change in western hydrology already under way.

Composite standardized temperature anomolies

Jan to Dec 2000 to 2005

versus 1895–2000 longterm average

-2.00 -1.50 -1.00 -0.50 0.00 0.50 1.00 1.50 2.00 

NOAA–CIRES/Climate Diagnostics Center

Figure 8—Departure from average temperature, 344 United States climate divisions, for the 72-month 

period from January 2000 through December 2005, expressed as departure in standard deviations from 

1895-2000 mean. Analysis: NOAA Climate Diagnostics Center.

In the Western states late 

winter and early spring have 

shown the greatest rate of 

warming during the year...
15

Mountain glaciers in the western portions of the United States 

and Canada and in Alaska show widespread trends toward negative 

mass balances on an annual basis, cumulative mass loss, and retreat on 

a large scale (e.g., Burbank 1982, Hall and Fagre 2003, Hodge et al. 

1998, Luckman 1998, Naftz et al. 2002, Rasmussen and Conway 2004, 

Reichert et al. 2002).

In recent years there have been large die-offs in western forests 

on spatial scales not hitherto witnessed directly. In some areas (the 

Southwest) these forest effects have been driven primarily by drought, 

but also by related causes such as warm temperatures and insect growth 

(Northern United States and southern Canadian Rockies, where 

temperature has been the issue more than drought). Weiss and Overpeck 

(2005) present phenological evidence from vegetation of recent warming, 

especially minimum temperature, in the Sonoran Desert. The Southwest 

has experienced two large and lengthy droughts in the last half century, 

one in the mid 1950s and one from 1999-2004 (maybe not over yet). 

The second drought was during the warmer regime shown in figures 1 

and 2; the increased temperature appears to have exacerbated the effects 

of insects. In the Rockies of the Northern United States and Southern 

Canada, insect pests such as pine beetles are affecting elevations and 

tree species where they have not been previously seen. In some elevation 

bands, mild winters are permitting overwintering while longer summers 

are permitting a second generation in one year, speeding insect life cycles 

and overcoming the defense mechanisms of trees not accustomed to such 

assaults (Logan and Powell, submitted).

Long-term surface monitors at higher elevations are difficult to 

find, especially in North America and in the United States (see Diaz 

and Bradley 1997, and Diaz et al. 1997 and papers therein). Evidence 

of high elevation effects can be obtained from the National Center for 

Atmospheric Research/National Centers for Environmental Prediction 

(NCAR/NCEP) “Reanalysis” (Kalnay et al. 1996, Kistler et al. 2001). 

Operational weather models and data assimilation techniques are 

constantly being refined and changed. The concept of Reanalysis is to 

“freeze” the analysis and assimilation methods using a recent modern 

model, and re-process all the original input data from the last 3-5 decades 

(which has all been saved!) so that changes in processing are not the 

source of the subtle variations of interest for climate. Though laborious, 

this approach has proven to be well worth the trouble. Time series 

of temperature data at 700 mb (10,000 ft [3000 m]) taken from the 

Reanalysis shows winter and annual trends not too dissimilar from those 

of the cooperative network at the surface seen if figures 1, 2, and 4. These 

values, based largely on weather balloons, do not include precipitation. 

It is not known definitively whether high elevations have warmed or will 

warm differentially compared to low elevations, and it is very important to 

improve this understanding (Karl et al. 2006, Pepin and Seidel 2005).

In recent years there have 

been large die-offs in 

western forests on spatial 

scales not hitherto witnessed 

directly.

In the Rockies of the 

Northern United States and 

Southern Canada, insect 

pests such as pine beetles are 

affecting elevations and tree 

species where they have not 

been previously seen. 
16

What is Expected with Climate Change, 

and with What Certainty

The climate elements of most interest to resource managers are 

precipitation and temperature. Fortunately, these are the most widely 

measured and reported and have the longest time series. Other common 

elements of interest to resource managers include snowfall, snow depth, 

absolute or relative humidity, wind speed and direction, solar radiation, 

clouds and sky conditions, and soil temperature and moisture. The 

relevant statistical climate descriptors of most interest are usually means or 

totals over days, months, or seasons. Others wish to know the likelihood 

of threshold exceedance, because natural resource systems are unduly 

affected by rare extreme events and disturbances, that result in, for 

example, mortality, lack of mortality (for pests), erosive events, fire, or 

other ecosystem disturbance. Redmond (1998) presented an overview of 

many of the principal climate change issues in the West.

Temperature is the element in which there is the most confidence in 

the ability to project future trends. Temperature is a continuous variable 

in the atmosphere (it is always present), we have ample experience with 

it, and many biological and chemical processes are highly correlated 

with temperature. In the West, with its many dependencies on snow, 

temperature is an important hydrologic element, even though it is not 

often thought of in those terms. As figure 4 shows, there is significant 

coherence among forecast models for the next several decades for a 

relatively steady rate of warming. This combination of expectations 

approximately matching ongoing observed trends seems sufficient to 

instill at least moderate confidence in further expectation of continued 

warming of the Western states. Furthermore, there is reason to believe that 

nighttime minimum temperatures are likely to warm more than daytime 

maximum temperatures. Humans may pay more attention to daylight 

conditions, but natural systems are exposed at all times. More generally, 

all natural systems take notice of all climatic factors in their immediate 

environment and respond to them, whether nearby humans in their 

buffered environments do or not.

It is interesting to note that in the nearly four decades since Manabe 

and Wetherald (1967) used a simple one-dimensional model to estimate 

that global climate would warm by about 2oC with doubled CO2, a 

finding that has changed relatively little with far more sophisticated 

models. Nonetheless, until these models have attained a longer track 

record, and have proven themselves in more demanding contexts, there 

remains the possibility that they are missing or misrepresenting processes 

of importance, and results should not be accepted as gospel. They are tools 

for planning, diagnosing and understanding, and as long as this point is 

kept in mind, they can be extremely useful. 

With respect to precipitation, as with daily weather this element is 

much harder than others (such as temperature) to forecast at longer time 

scales, weeks to decades. Precipitation is discontinuous in the atmosphere, 

not present everywhere and every moment, so one has to first forecast the 

development of a storm or cloud, and then secondly obtain the amounts. 

Temperature is the element 

in which there is the most 

confidence in the ability to 

project future trends. 

...there is reason to believe 

that nighttime minimum 

temperatures are likely to 

warm more than daytime 

maximum temperatures. 

Humans may pay more 

attention to daylight 

conditions, but natural 

systems are exposed at 

all times. 
17

Cloud effects must be parameterized, since no present climate model can 

afford the resources to try to resolve the formation of individual clouds 

(and, there are many kinds of clouds). Winter systems are more likely to 

be simulated correctly, because of their large scale. Summer convection is 

much harder to simulate accurately. Likewise, monsoon systems present 

a real challenge to climate models. Manabe et al. (2004) note that on 

a global basis, current wet places are likely to become wetter, and other 

locations may experience more water stress. 

For precipitation over regions the size of typical western river basins, 

there is much disagreement among models, there are many issues of 

scale (spatial and temporal), the track record does not seem impressive, 

and the best advice for managers is to be very circumspect, take care in 

trusting any of the model results too much, and to use model results 

for precipitation as scenarios and potential futures. Attempts are being 

made to address this uncertainty more directly by expressing results as 

probability distributions (e.g., Dettinger 2004). Trenberth et al. (2003) 

emphasized that too much focus may be placed on precipitation amount, 

rather than other important characteristics that may change (frequency, 

timing, intensity, statistical distributions, extremes, types of events, 

etc). Meehl et al. (2000) discuss the impacts of changes in extreme of 

climate. Groisman et al. (2001, 2004) report on changes in the frequency 

distribution of precipitation and streamflow in the United States, with 

upward trends especially in the heaviest end of the frequency distribution, 

and in recent decades. With such extreme differences in precipitation 

climatology over short horizontal distances, much care must be taken 

in the West when interpreting the correspondence between model 

projections and observations (examples in Groisman et al. 2005). 

Snow and snowpack result from a combination of temperature and 

precipitation processes. To the extent that models can get the precipitation 

approximately correct, they have good prospects of utilizing their 

better temperature performance to provide diagnostic and prognostic 

inferences about snow depth and water content. Snow depth is important 

to plants (protection via coverage) and to animals (or their predators) 

that hibernate or that must forage or migrate through deep snow, and 

to snowplows, skiers and snowmobiles. Snow water content is important 

to water supplies, soil recharge, stream runoff, snow loading for design, 

rafters, early summer hikers, forest road design, and many others. Climate 

projections in nearly all cases are for snow levels to rise, and for endof-winter snowpack and snow depth to decline, except at the highest 

elevations (less cold, but still below freezing) and in those locations where 

precipitation might increase (Christensen et al. 2004; Knowles and Cayan 

2002, 2004; Van Rheenen et al. 2004). Barnett et al. (2005) estimate that 

about 1/6 of the world population receives its water supply from ice and 

snow, and is at risk of disruption from warming. Models, and empirical 

studies (see below), indicate that lower mountains, closer to the mean 

freezing level, are especially vulnerable to decreases in snowpack.

Along these lines, Mike Dettinger (reported in Bales et al., submitted) 

has performed a very informative vulnerability analysis, based largely on 

observed behavior, using the Variable Infiltration Capacity (VIC) model 

For precipitation over 

regions the size of typical 

western river basins, there is 

much disagreement among 

models, there are many 

issues of scale (spatial and 

temporal), the track record 

does not seem impressive, 

and the best advice for 

managers is to be very 

circumspect...

Models, and empirical 

studies, indicate that lower 

mountains, closer to the 

mean freezing level, are 

especially vulnerable to 

decreases in snowpack.
18

(Liang et al. 1994, 1996) at the University of Washington. In important 

catchments much snow falls near the freezing point. For example, in the 

Sierra Nevada, Blue Canyon at elevation 5,280 ft (1609 m) averages about 

248 in (630 cm) of snow with a mean winter temperature of 36oF (+2oC), 

whereas the Central Sierra Snow Lab 20 mi (35 km) east toward the Sierra 

crest on Interstate 80 at 6,883 ft (2098 m) receives 451 in (1145 cm) of 

snow with a mean winter temperature of 28oF (–2oC). Both locations 

have similar total winter precipitation. Assuming a modest change in 

temperature of about +3oC, daily time series are examined at each 1/8

degree VIC grid point to estimate the change in likelihood of a former 

snow event changing to a rain event because of the temperature increase. 

These results are shown in figure 9. 

This analysis shows that the entire West Coast (Sierra/Cascades) is 

seen to be quite vulnerable to modest increases in temperature. Much 

precipitation that now falls as snow would fall in the future as rain, so 

that snowpack would decline if precipitation amounts stayed the same. 

The state of Idaho and parts of the Great Basin are next most vulnerable. 

The highest, and thus coldest, mountains in Colorado, and the southern 

High Sierra, with its limited spatial area, are less vulnerable. Heavy rain 

events in winter, and rain-on-snow events, would likely increase (even 

with no increase in precipitation). Knowles et al. (submitted) report that 

rain/snow ratios have already begun to change in the Western United 

States; Huntington et al. (2004) are reporting a similar result for the 

Northeast United States. These have significant consequences for reservoir 

management, in attaining a seasonally evolving balance between flood 

control (empty reservoirs are best) and preservation of water supplies (full 

reservoirs are best). In many of these model runs, higher precipitation 

variability leads to the seemingly paradoxical and perverse result that 

the likelihood of both floods and dry spells and droughts goes up. This 

odd result does indeed appear physically plausible, and perhaps we have 

been witnessing this in the past 30 years. The summer dry season would 

generally begin earlier and end later, so that the evaporative demand 

season would be longer, and likely exaggerate fire danger. 

Additional studies (Dettinger et al. 2004, Hamlet and Lettenmeier 

1999, Jeton et al. 1996, Kim 2005, Kim et al. 2002, Leung et al. 2004) 

anticipate changes in the timing of many snowmelt driven systems. 

Miller et al. (2003) examine the effects of climate change on California 

hydrology. Others have gone further and attempted to determine 

biological effects of warmer streams, such as on fish populations (e.g., 

Gooseff et al. 2005 and references therein). Hayhoe et al. (2004) discuss a 

variety of issues pertinent to climate change in California.

Models with subsurface structure indicate that warming seems more 

likely to reduce rather than to increase soil moisture. In part this stems 

from a longer and warmer vegetative water demand season, and from less 

efficient recharge in the mountains in winter. With respect to atmospheric 

moisture, we do not have high quality long-term observations of humidity 

trends, and are unlikely to obtain these soon from in situ ground-based 

sensors. Wind also affects soil moisture and evapotranspiration, but is 

one of the most difficult elements to measure accurately and consistently 

This analysis shows that the 

entire West Coast (Sierra/

Cascades) is seen to be 

quite vulnerable to modest 

increases in temperature.

...higher precipitation 

variability leads to the 

seemingly paradoxical and 

perverse result that the 

likelihood of both floods 

and dry spells and droughts 

goes up.
19

over many years, and we have very few first-class long-term wind records. 

Probably the best wind record in the West is the one starting 1944 at the 

Hanford Meteorology Station tower that continues to the present.

Unlike CO2, aerosols vary greatly in their concentrations and 

properties from place to place (Kaufman et al. 2002), can travel long 

distances (Koch and Hansen 2005), and can affect climate in a variety of 

ways (Ramanathan et al. 2001). Increased numbers of small particulates 

can create too many small droplets, which make the mechanisms of 

precipitation formation less efficient. Small droplets do not coalesce well 

into drops large enough to fall to the surface. Evidence exists suggesting 

that particulate pollutants are changing the amount of precipitation 

in western mountains (Borys et al. 2000, 2003; Givati and Rosenfeld 

2004; Rosenfeld 2000; Rosenfeld and Givati, in press). Clouds in 

general continue to provide one of the most vexing problems in climate 

simulation (Randall et al. 2003). Contrails have both cooling and 

warming effects and are becoming more common (Minnis et al. 2003, 

2004). Together, clouds and aerosols pose some of the most daunting 

challenges to more accurate modeling of climate. Much of the basic 

problem has to do with how radiation flows through the atmosphere, a 

subject concisely described by NRC (2005). The global effect of human 

aerosol contributions is proving to be quite substantial (Bellouin et al. 

2005). In general these aerosols act as a cooling influence on global 

climate by reflecting radiation from the system. Because they originate 

from processes similar to those that produce greenhouse gasses, there 

remains a possibility that removal of these aerosols from the air for health 

reasons may release what is in effect now a partial “brake” on climate 

warming.

Fraction of annual precipitation falling

in the daily tempture range: -3C < Tavg < 0C

[from 1950-1999 VIC 1/8-degree INPUT DATA]

Fraction 

120°W 105°W 90°W 75°W

0.00 0.15 0.25 0.35

45°N

30°N

Figure 9—Fractional change of mean annual precipitation falling as snow to falling as rain, with a +3 C 

change in mean temperature. Redder areas are more vulnerable to small temperature rises. Courtesy Mike 

Dettinger, from Bales et al. (2005).

Together, clouds and 

aerosols pose some of the 

most daunting challenges 

to more accurate modeling 

of climate. 
20

Mountains enhance precipitation, often greatly. The mechanisms 

are complex and subtle, and evidence and theoretical considerations 

suggest that the amount of enhancement varies within storms, from 

storm to storm, from winter to winter, and on longer time scales. In 

some mountain ranges the phase of ENSO makes a difference (Dettinger 

et al. 2004). Numerical experiments (e.g., Grubisic et al., submitted) 

and experience (Leffler et al. 2001) strongly suggest that orographic 

effects operate at scales of hundreds of meters or less. A clear need exists 

for model studies at finer scales (Leung and Qian 2003; Leung et al. 

2003a, 2003b). Changes in cloud microphysics, flow trajectories, and 

temperatures can cause changes in orographic enhancement (ratios of 

high elevation to low elevation precipitation). Orographic effects can be 

highly sensitive to slight changes in trajectory and enhanced or changed 

by barrier winds (Nieman et al. 2002, 2004; Ralph et al. 2003; White et 

al. 2003).

The reasons for summer to summer variations in regional 

precipitation systems like the Southwest monsoon (July, August and 

sometimes September) are only dimly understood. Monsoon precipitation 

is difficult to forecast more than a few days in advance. It is known that 

monsoon season precipitation totals in Arizona and New Mexico are 

not highly correlated (Gutzler 2000, Mitchell et al. 2002). Gutzler and 

Preston (1997), Gutzler (2000), and Lo and Clark (2002) report on 

a potential relation between prior winter snow cover and timing and 

amount of monsoon rains. 

Our confidence in accuracy of attribution will improve when there 

is a better match between theory and observation, and when we can 

successfully trace changes in energy flow and storage in the climate 

system. The oceans represent a major sink for energy; Hansen et al. (2005) 

has recently reported progress on accounting for Earth’s energy imbalance, 

which appears to be going into warming of the world’s oceans (Levitus 

et al. 2000, 2001, 2005; Willis et al. 2004). Pielke (2003) has argued 

that ocean energy storage rates constitute an important climate metric 

and must be better known. At this point there is no single improvement 

that is widely foreseen that would provide a quantum leap in quality and 

accuracy of climate forecasts. Rather, any improvements are likely to be 

the result of numerous incremental advances, slowly chipping away at this 

difficult problem. New techniques to combine multiple runs of multiple 

models (“super-ensembles;” Kharin and Zwiers 2002, Krishnamurti et al. 

2000) offer additional promise for improved bounds on uncertainty. It is 

certainly clear that this arid region cannot be understood or predicted well 

until we incorporate better its relations to the world ocean. 

Large Scale Teleconnections

Spatial patterns of climate variability in the Western United States are 

correlated with patterns of climate variability in other parts of the world, 

the teleconnections referred to earlier. For example, it is known that winter 

precipitation in the West frequently exhibits a “dipole” pattern (wet in 

the Pacific Northwest and dry in the Desert Southwest, or vice versa), and 

that this pattern is strongly related to tropical Pacific ocean temperatures 

Our confidence in accuracy 

of attribution will improve 

when there is a better 

match between theory and 

observation, and when 

we can successfully trace 

changes in energy flow 

and storage in the climate 

system. 

...any improvements are 

likely to be the result of 

numerous incremental 

advances, slowly chipping 

away at this difficult 

problem. 
21

and to atmospheric pressure patterns in the Southern Hemisphere 

(Redmond and Koch 1991). The sense of the relation is such that El Niño 

is associated with wet winters in the Southwest and dry winters in the 

Northwest and northern Rockies; La Niña is associated with dry winters 

in the Southwest (very reliably: no exceptions in 75 years) and wet winters 

in the Northwest and northern Rockies. 

There is much popular confusion between El Niño itself and the effects

of El Niño. El Niño refers (only, and exclusively) to ocean warming in the 

top 100-200 meters in a narrow band between South America and the 

Date Line, typically within 5 degrees latitude of the equator. The effects 

of El Niño, by contrast, are global in reach. At time scales of a few years 

or less, outside of the seasons El Niño is the largest contributor to climate 

variability on earth. The warm area may look small on a map of the 

Pacific, but can easily be larger than the United States. The exact shape, 

magnitude, extent, duration, and longitudinal position of the warm water 

patch can vary from one episode to the next, factors that can significantly 

influence the impacts on the West (Hoerling and Kumar 2002). Typical 

events last 6-18 months, and recur irregularly at 2-7 year intervals. La 

Niña refers to unusually cool temperatures in this same area. El Niño 

exhibits characteristics of an oscillation in the sense that during one 

phase of the cycle forces are at work that lead to the demise of that phase 

and often even the eventual growth of the opposite phase, like a very 

complicated pendulum, albeit one subject to irregular forcing by short 

term weather events. 

The atmospheric pressure difference Tahiti minus Darwin (Australia) 

is negatively correlated with ocean temperatures in the El Niño /La Niña 

area, a phenomenon known as the Southern Oscillation. For historical 

reasons these two descriptions have been lumped together as ENSO (“El 

Niño /Southern Oscillation”). The magnitude of this correlation, usually 

strong, has varied somewhat through time (McCabe and Dettinger 

1999), so the atmosphere and the ocean each carry somewhat different 

information. Other descriptive measures have been developed more 

recently, such as the Multivariate ENSO Index (MEI) by Wolter and 

Timlin (1993). El Niño and La Niña are now simulated by many models 

that couple the atmosphere to the ocean, a necessity for El Niño to appear 

in them. They can thus be predicted with some success, as can their effects 

in North America and elsewhere. In the Western United States the effects 

of El Niño and La Niña are experienced in the cold half of the year, from 

approximately October through March; summer signals are very weak. 

The climatic effects of ENSO are also found in streamflow (Andrews et 

al. 2004, Barnett et al. 2004) where they are greatly accentuated with 

respect to precipitation (Cayan et al. 1999) in the Western states. Because 

annual tree growth in the Southwest is strongly dependent on prior 

winter precipitation, these ENSO effects are clearly seen in tree ring 

widths (Swetnam and Betancourt 1990). The West is “fortunate” in that 

temperature and precipitation over large areas can be predicted with some 

skill at 3-7 month lead times, and 6-9 month lead times for the summer 

streamflow runoff. 

There is much popular 

confusion between 

El Niño itself and the 

effects of El Niño.

In the Western United States 

the effects of El Niño and 

La Niña are experienced 

in the cold half of the year, 

from approximately October 

through March...
22

The frequency of El Niño has varied through time. During the period 

1947-1976 El Niño occurred relatively infrequently and La Niña was 

common. A sudden and still unexplained change (the “1976 shift”) in the 

Pacific ushered in an era of much more common El Niño and a virtual 

dearth of La Niña. This appeared to many observers to have switched 

again in the late 1990s, though present evidence remains somewhat 

ambiguous. This long “cycle” of about 50 years duration is expressed 

in a pattern of ocean temperatures, atmospheric pressures, jet stream 

positions, and ocean currents seen from the tropics to the high latitudes 

in the Pacific, first described by Mantua et al. (1997) and Mantua and 

Hare (2002) as the Pacific Decadal Oscillation (PDO) and elaborated by 

others. They related the PDO to strong differences in salmon abundance 

between Alaska and the Pacific Northwest. There is much debate about 

the origin of the PDO, whether it truly is an oscillation, and even whether 

it really exists except as a (multi-year) filtered effect of El Niño (Newman 

et al. 2003) with strong elements of chaotic behavior (Overland et al. 

2000). Thus far, models have been unable to faithfully simulate the 

behavior of the PDO, particularly transitions from one phase to the other, 

or its possible effects on temperature or precipitation in Western North 

America, despite tantalizing evidence that there are such effects. For now, 

ENSO has predictive value, but the PDO remains primarily diagnostic. 

Brown and Comrie (2004) saw the same western “dipole” at longer time 

frames in the PDO signal as seen on the shorter time scales of ENSO 

(e.g., Redmond and Koch 1991); McCabe and Dettinger (2002) see this 

dipole on both time scales in the historical Western United States snow 

course data. 

Another kind of connection operates in the Pacific at intermediate 

time scales of approximately 40-70 days. Pairs of mostly cloudy and 

mostly clear regions slowly drift eastward from the Indian Ocean toward 

the Western Pacific, a phenomenon known as the Madden-Julian 

Oscillation (MJO), or sometimes, Intra-Seasonal Oscillation (ISO). 

Interactions with the eastward flowing jet stream coming off Asia can lead 

to multi-day precipitation episodes on the West Coast 5-10 days later 

(Mitchell and Blier 1997, Mo 1999, Mo and Higgins 1998). These are 

important because much of the annual precipitation occurs in the largest 

3-5 storms of the 20-25 that typically strike the coast of California in 

winter.

Quite clearly, there are long term phenomena in the Pacific that 

require explanation and understanding (see Zhang et al. 1998, for an 

overview). Attempts to further extend these records must rely on proxy 

paleoclimatic data, such as tree rings (Biondi et al. 2001; D’Arrrigo et 

al. 2001, 2005; Gedalof and Smith 2001; MacDonald and Case 2005; 

Wiles et al. 1998), corals (Gedalof et al. 2002) and nitrogen isotopes in 

salmon (Finney et al. 2002). The relevance of variations on these scales 

is that slow natural changes appearing in the short sample afforded by 

historical records (50-150 years) can masquerade (perhaps) as “climate 

change” if our temporal perspective for interpretation is too short. The 

PDO shifted abruptly in 1976, at about the time when the temperatures 

shown in figure 1 began to warm. Our best global climate observations 

are unfortunately from this very same post-World War II period, and thus 

A sudden and still 

unexplained change (the 

“1976 shift”) in the Pacific 

ushered in an era of much 

more common El Niño 

and a virtual dearth of La 

Niña. This appeared to 

many observers to have 

switched again in the late 

1990s, though present 

evidence remains somewhat 

ambiguous. 
23

nearly coincide with this approximately 50-year long period of the PDO 

(1947 to latter 1990s). One might interpret this in two ways: (1) some 

of the recent warming in Western North America is a natural effect due 

to the mid-1970s phase change of the PDO, or (2) the climate system 

has “selected” this pattern to express the effects of climate warming 

(some climatic changes are likely to appear in the form of pattern 

changes). However, western warming has continued into 2005, seemingly 

independent of the phase of the PDO. From a management perspective, 

it is of interest to note that climate variations of 2-3 decade duration 

roughly correspond to the length of a typical career.

Emboldened by these findings of recurrent behavior, the research 

community has been examining connections between additional aspects 

of Western United States climate and hydrology and other oscillatory 

phenomena. Among the latter are the North Atlantic Oscillation (NAO) 

for both instrumental (Hurrell 1995, Marshall et al. 2001) and millennial 

time scales eras (Cook et al. 2002), the related Arctic Oscillation (AO) 

(Thompson and Wallace 1998, 2000, 2001; Wu and Straus 2004), and 

the Atlantic Multidecadal Oscillation (AMO) (Enfield et al. 2001, Gray 

et al. 2004b, McCabe et al. 2004). It is more difficult to understand 

the cause and effect chain with a “downwind” ocean like the Atlantic 

compared with an “upwind” ocean like the Pacific, but the statistical 

associations are suggestive and intriguing. Also, one would expect these 

Atlantic couplings to vary between winter and summer. The Atlantic 

would seemingly have more “opportunity” to affect Western North 

America when the Bermuda High shifts northward in early summer and 

a broad flow from east toward west develops at lower latitudes on its 

southern flank. In winter, the broad flow over Western North America 

nearly always has a component directed from west toward east.

Much of the (relatively modest) skill that now exists at lead times of 

1-12 months arises from two sources, ENSO and (continuation of) recent 

trends (Quan et al., submitted). Until about 2004 statistical approaches 

and dynamical models showed rough parity in their respective abilities 

to forecast upcoming seasons. However, after about 50 years of long-lead 

forecasting in the United States, in an inevitable development dynamical 

models have begun to pull slightly ahead of statistical models, and in the 

long run they will have much more potential. To maintain this progress, 

a new framework, known as the Climate Test Bed, has emerged, currently 

centered around the Climate Forecast System (Saha et al. in press ). The 

goal is to systematically add and improve the representation of climate 

factors in forecast models for the upcoming 1-12 months (CPC 2005a, 

2005b).

The climate research community has recently begun to make a 

concerted effort to understand the cause of decadal-to-centennial scale 

climate variability. In the West, modern (e.g., Cayan et al. 1998) and 

paleoclimate (e.g., Cook et al. 2004; Fye et al. 2003; Gray et al. 2004a, 

2004b; Hughes and Brown 1992; Stahle et al. 2000, 2001; Woodhouse 

2003; Woodhouse and Overpeck 1998; Woodhouse et al. 2005) records 

have firmly established that long-term drought (5-20 years and more) is 

an inherent part of climate variability in this dry region. Recent model 

From a management 

perspective, it is of interest 

to note that climate 

variations of 2-3 decade 

duration roughly correspond 

to the length of a typical 

career.

The climate research 

community has recently 

begun to make a concerted 

effort to understand 

the cause of decadal-tocentennial scale climate 

variability.
24

studies to understand the source of the 1930s Dust Bowl (Schubert et 

al. 2004a, 2004b; Seager et al. 2005), the 1950s Southwest drought, and 

the intense 2000-2004 drought (Hoerling and Kumar 2003) have shown 

that a major part of the answer lies in the world’s oceans, in particular the 

Western Pacific and the Indian Oceans. These parts of the world ocean are 

also slowly warming (Levitus et al. 2000, 2005), with potential additional 

implications for the West. Hansen et al. (2005) have pointed to the energy 

imbalance at the top of the earth’s atmosphere arising from increased 

greenhouse gasses. These imply another 0.6oC of ocean warming yet to be 

realized at the surface (excess energy already residing in the system), even 

if all present human greenhouse emissions were to cease. The direct and 

immediate effect of greenhouse gasses is to reduce the radiative energy loss 

to space, without appreciably affecting the solar supply. The climate must 

warm to increase this energy loss rate so that it approximately equals the 

solar supply rate, but this warming cannot occur instantly.

Major Sectors

The impacts of climate variability and climate change are experienced 

differently by every sector, and often differently within sectors, depending 

on the exact set of circumstances. The manner in which events are 

sequenced can be a significant determinant of whether their impact is 

serious or inconsequential. Considerations for a selected set of sectors 

are discussed next. This list is not exhaustive and there is a continuum of 

variations on the underlying themes. 

Drought

The already arid West is the most drought prone part of the United 

States. At this writing the region has experienced its most significant 

drought in half a century, with no certainty that this episode is finished. 

Regardless, water supply systems for urban and rural populations, and 

for environmental needs, must be engineered to work with expected 

variability and long periods of shortage. Drought involves a mismatch 

between supply and demand, and consequent impacts, and thus is better 

defined in such terms (Redmond 2002). Burgeoning populations, and 

migrations to new locations, are placing new demands and increasing 

stress on western water supplies. New knowledge of past climates has 

led to the realization that very long droughts could occur and raise the 

question as to whether we are adequately buffered or otherwise prepared 

should they materialize. Swetnam and Betancourt (1998) discuss the 

major synergistic effects of drought, fire and insects that can be seen in the 

Southwest paleoclimate records, and how these can hinge on subtleties in 

their relationships.

Water Resources

The West is the most urban region (percentage of people living in 

cities) in the United States. A slow but inexorable shift is taking place as 

growing western cities and towns exert more influence on large scale water 

management decisions, and as agriculture steadily yields to development. 

Unlike agriculture, cities cannot lie fallow to during a poor water year, and 

The already arid West is 

the most drought prone 

part of the United States. 

At this writing the region 

has experienced its most 

significant drought in half 

a century, with no certainty 

that this episode is finished. 

Regardless, water supply 

systems for urban and 

rural populations, and for 

environmental needs, must 

be engineered to work with 

expected variability and long 

periods of shortage. 
25

thus reliability is paramount. The environmental footprints of the West’s 

cities extend all the way to the headwaters of its major river systems, and 

increasingly to groundwater, both typically recharged by snow. Systems 

have been designed to accommodate the measured climates and flows. 

Lately, some water managers have taken an interest in utilizing longer 

estimates from paleo (pre-historical) records. However, the prospect of 

climate change leads to a major and unanswered question: What part of 

the climatic past is relevant to what part of the climatic future? Already, 

snowpack appears to be declining. Very few cities have factored in the 

prospect of climate change with respect to water planning, or even know 

how to do so. This is emerging as a significant issue, and is commingled 

with the ubiquitous growth issue affecting nearly every part of the West 

(Lund et al. 2003). Water decisions by the urban centers will have 

significant repercussions well upstream and often out of the basin. Few 

studies have comprehensively examined vegetative demand changes. 

Rind et al. (1990) did examine this issue from a drought perspective, 

but western droughts are typically more associated with snowfall deficit. 

Hidalgo et al. (2005) estimate that a +3 C temperature change in 

California would (all else unchanged) lead to about a 6 percent increase 

in evapotranspiration. Pan evaporation values have decreased (Roderick 

and Farquhar 2002) in the United States, but there are many possible 

reasons for this, climatic and observational. The geographic synchroneity 

of variations in streamflow greatly affects whether there is inter-regional 

“compensation” among anomalies, and thus is of much interest to water 

and power managers (Cayan et al. 2003, Hirschboeck and Meko 2005); 

evidence exists that such relations are not constant (Jain et al. 2005). 

Timber and Forestry

The eventual fate of a tree is to be blown down, burned down, or 

cut down. Two of these involve the atmosphere, and the susceptibility to 

those outcomes is increased by weather and climate behavior and often 

by insects. Much of the life of insects is in turn controlled by climate, 

particularly temperature. Changes in climate have potentially significant 

consequences for insects (Williams and Liebold, 2002). Trees can also 

be harmed by pollutants that are either advected from afar or created 

in place through photochemical reactions. Both sources are closely tied 

to weather and climate. As with other plants, trees also will exhibit 

differential physiological responses to increased CO2 concentrations, a 

direct consequence of this greenhouse gas, and CO2 may modulate the 

response to factors such as ozone. Climate affects the growth of seedlings, 

and changes in microclimate induced by clearcuts have been shown to 

affect regeneration (Childs and Flint 1987). Thus, even neglecting fire, 

there are many ways in which weather and climate phenomena can affect 

forest management.

Fire

Fire is an integral component of forest and range communities, and 

knowledge of its many roles is improving steadily (Baird et al. 1999, 

Brown and Smith 2000, Christensen et al. 1989, Foster et al. 1988, 

Grissino-Mayer and Swetnam 2000, Heyerdahl et al. 2001, Johnson 

Very few cities have factored 

in the prospect of climate 

change with respect to water 

planning, or even know how 

to do so. This is emerging 

as a significant issue, and 

is commingled with the 

ubiquitous growth issue 

affecting nearly every part 

of the West...
26

and Miyanishi 2001, many others). Climate and weather events are 

major factors affecting fire vulnerability and potential, ignition, spread, 

suppression when needed, and regeneration. Climate information, 

expressed probabilistically, can be useful for planning of prescribed 

burns, with adjustments that take into account the presence or absence 

of drought, and forecasts at various lead times from two weeks to a day 

are available when active intervention is desired. Westerling et al. (2002, 

2003) have developed techniques that show some skill at longer lead times 

in forecasting aspects of upcoming fire seasons. Precipitation can increase 

or decrease fire potential, depending on the time of year, the particular 

seasonal climatological background, the type of fuel, and the recent 

weather history. On longer time scales, the general effect of warming, with 

no change in precipitation patterns, would be for increased dryness of 

soils and vegetation, lengthened summer dry seasons, and lower relative 

humidity. Brown et al. (2004) discuss climate change effects on wildland 

fire. Some areas that presently do not burn often, such as coastal fog 

belts and higher elevations, might experience significant change toward 

greater susceptibility, especially in the zone below timberline. Some forests 

of significant aesthetic and economic value (e.g. the redwoods) are tied 

to small scale phenomena (coastal winds and upwelling, systems with 

dimensions of 5-50 km [3-31 miles]) that await high-resolution longterm climate simulations likely embedded in large scale global models. At 

present it is unknown whether the summer fog belt along the West Coast 

will change appreciably, though some models hint at modest warming 

and lower humidity. Few climate studies have addressed whether wind 

and cloudiness, both factors that affect plant and soil moisture budgets, 

will increase or decrease, or which general settings will experience which 

effects.

Recreation

Every corner of the diverse western landscape is host to some form 

of recreation, including tourism, camping, rafting, windsurfing, biking, 

hiking, snowmobiling, climbing, motorcycling, boating, four-wheeling, 

fishing, hunting, backpacking, skiing, boating, picnicking, photographing 

and just plain relaxing, to name but a few. The West has a long-standing 

outdoor orientation. All such activities are greatly affected by long and 

short term events in the atmosphere, exposure to ultraviolet radiation, and 

the condition of streams, lakes and reservoirs. Preparation for visitation 

to national parks and other public lands is often planned according 

to expected climate, and numerous last minute decisions are made on 

the basis of recent or upcoming weather. In some locations climate is a 

primary park attractant (the Olympic rain forest, the ice of Glacier and 

Rainier and North Cascades, the fog of Channel Islands, the snow of 

Crater Lake, even the heat of Death Valley). Festivals and gatherings are 

planned on the basis of climate expectations. A large number of local 

and regional economies are tied to seasonal recreation. Forest closures 

from drought or fires have significant financial impacts, and political 

dimensions. Summer homes extend the wildland-urban interface and 

habitat fragmentation ever farther out from cities. Warmer temperatures 

will drive people to cooler, higher, more comfortable climate zones. 

Climate and weather events 

are major factors affecting 

fire vulnerability and 

potential, ignition, spread, 

suppression when needed, 

and regeneration.

A large number of local 

and regional economies are 

tied to seasonal recreation. 

Forest closures from drought 

or fires have significant 

financial impacts, and 

political dimensions.
27

Grazing

The rural and agrarian traditions in the West remain alive in the 

widespread presence of cattle and sheep on public lands. Managers 

of these range and forest lands would prefer that grazing intensity be 

optimized according to the present status and expected trends of forage 

and drought indicators. Personnel limitations do not allow on-site visits 

to evaluate conditions on every patch of ground. Automated climate 

monitoring sites feeding into spatial and temporal models, in concert 

with satellite information, is greatly desired. Such sites need long records 

for calibration, and for ground truth of remote sensing data. Techniques 

are needed to interpolate and map such information, in forms that assist 

with making decisions. Invasive plants and animals are a major issue in 

much of the interior West, and indeed in nearly ecotone. Climate is a 

major factor in the invasion process itself, as well as in establishment and 

consolidation of new species. Disturbances that facilitate invasions (such 

as fire or drought) often have a climatic origin or strong component.

Monitoring Needs

There are a number of motivations for monitoring of climate, from 

reasons related to forecasting and modeling (Goody et al. 2002) to 

those that support myriads of operational and practical decisions (NRC 

1998, 1999, 2001). Although Lewis and Clark carried thermometers 

from 1804-1806 (Knapp 2004, Solomon and Daniel 2004), systematic 

weather and climate measurements did not begin until the settlement of 

the West commenced in earnest, particularly through the forts and the 

Signal Corps (recounted in, e.g., Moran and Hopkins 2002). A large 

increase in the number of stations occurred during 1890s, and these form 

the backbone of our current historical surface climate data set. Most 

historical networks are biased toward locations where humans live and 

work, and thus the higher and more remote locations of the West have 

generally been severely underrepresented. These regions are, however, the 

source of most of the natural resources that urban centers depend on. 

Because the underrepresented areas have very different climates (colder, 

wetter, snowier, windier) from those of population concentrations, spatial 

averages that do not account for these differences will be biased toward 

values representative of lower elevations. Figure 10 shows that in the Great 

Basin, the upper elevations supply a disproportionate share of annual 

precipitation. 

The Nation has long relied on the NOAA (National Oceanic and 

Atmospheric Administration) cooperative network maintained by the 

National Weather Service (NWS) and on airports (NWS and Federal 

Aviation Administration, FAA) sites. However in the Western states 

the interagency RAWS (Remote Automatic Weather Station) and U.S. 

Department of Agriculture/Natural Resources Conservation Service 

(USDA/NRCS) Snotel system provide an invaluable and substantial 

augmentation, as both are designed for duty in the locations where 

crucial natural resources are located. Neither of these were designed or 

deployed specifically as “climate” networks, though they are increasingly 

used in that way and will continue to be. With improved technology, 

Invasive plants and animals 

are a major issue in much of 

the interior West...Climate 

is a major factor in the 

invasion process itself, as 

well as in establishment 

and consolidation of new 

species. Disturbances that 

facilitate invasions (such as 

fire or drought) often have 

a climatic origin or strong 

component.

Although Lewis and Clark 

carried thermometers from 

1804-1806...systematic 

weather and climate 

measurements did not begin 

until the settlement of the 

West commenced 

in earnest...
28

added stations and networks are appearing. Most networks were deployed 

to serve particular constituencies that must continue to be satisfied, 

whereas a few (e.g., NWS cooperative network) have served a general 

multipurpose role of benefit to every citizen. Lists of uses for climate 

information can be found in NRC (1998, 2001). 

However, there still remains no comprehensive coordination to these 

observing efforts, and the special need of climate–long term consistency 

and careful attention to siting–is not a mandated priority. This, especially, 

remains a critical need for the region. Detailed discussions of these issues 

can be found in Redmond and McCurdy (2005) and Redmond et al. 

(2005). The West is unevenly sampled, mostly as a consequence of a 

large variety of individual decisions pertaining to expressed local needs. 

The high elevations are especially undersampled, with most of the West’s 

approximately one thousand mountain ranges having no instrumentation 

at all. There is presently no coherent strategy among all public, or even 

federal, agencies to coordinate the location, sensors, communications, 

siting, and maintenance criteria, or expected minimum standards, needed 

to establish a West-wide climate observing network. Many bits and 

pieces do exist, however. Strategies have been developed for estimating 

desired station density (e.g., Janis et al. 2004, Vose and Menne 2004) 

but these often address a well-defined observing need. Observation needs 

vary widely, depending on intended use, and there are difficult issues of 

spatial scale, because climates in physically close locations can exhibit very 

different properties. This is especially true for ecological studies, where the 

climate at the scales of communities and organisms and their ranges is the 

most relevant. A major shortcoming with the present observing system is 

the shortage of soil moisture observations. Soil moisture status is affected 

by a variety of processes and parameters, and serves as an integrating 

property. Likewise, snow is a critical element for western hydrology, 

and stands to be greatly affected if climate changes. Snow is difficult to 

100%

90%

80%

70%

60%

50%

40%

30%

20%

10%

0%

% of total

Elevation (m)

0 500 1000 1500 2000 2500 3000 3500

Elevation Precipitation

0% total PPT Elev %

Nevada precipitation-elevation distribution

Figure 10—Cumulative distribution of elevation and of precipitation for the state of Nevada, based on 

30-year means from PRISM. Figure courtesy Chris Daly, Oregon State University. 

There is presently no 

coherent strategy among 

all public, or even federal, 

agencies to coordinate 

the location, sensors, 

communications, siting, 

and maintenance criteria, 

or expected minimum 

standards, needed to 

establish a West-wide 

climate observing network. 
29

measure (Doesken and Judson 1996) and although some studies of valley 

snows have been conducted (Karl et al. 1993, Scott and Kaiser 2004) we 

still do not understand the strengths and limitations of the national snow 

data base (Knowles et al., submitted; Kunkel et al., submitted).

Greater coordination is being promoted, through such efforts as the 

Consortium for Integrated Climate Research in Western Mountains 

(CIRMOUNT 2005), which has sponsored several meetings since 2004, 

advocating improved high elevation observations and understanding of 

fundamental processes and vulnerability to climate change. The highest 

such station is White Mountain Summit, east of the Owens Valley in 

California at 1,4245 ft (4342 m) reporting every ten minutes on the Web. 

Another similar effort is the interagency Western Mountain Initiative 

(WMI 2005). Of note is NSF’s effort to develop a series of “observatories” 

and associated communications and computer access infrastructure: 

NEON (National Ecological Observatory Network), Hydrologic 

Observatories through CUAHSI (Consortium of Universities for the 

Advancement of Hydrologic Science, Inc.), engineering and sensing with 

CLEANER (Collaborative Large-scale Engineering Analysis Network 

for Environmental Research), and ORION (Ocean Research Interactive 

Observatory Networks). NOAA has been attempting to upgrade its legacy 

cooperative network to 5-minute live reporting with NERON (National 

Environmental Realtime Observing Network), and USDA is similarly 

attempting to deploy a large number of Soil Climate Analysis Network 

(SCAN) sites to measure soil moisture (a major shortcoming identified 

by Western Governors Association 2004) and temperature (e.g., Hu 

2004). Both NERON and SCAN have been adding stations at a relatively 

slow pace, however. Many other smaller or specialty networks could be 

mentioned. Practical considerations lead to the clear conclusion that there 

is an enormous need for improved coordination among a very diverse cast 

of characters. 

Increasingly, resource management agencies are being urged to shore 

up the scientific underpinnings for their management decisions. It is also 

vital to know whether slow changes in abundance of individual species 

(e.g., Chavez 2003) is due to changes in climate or to changes in resource 

management; one phase of the PDO lasts about the length of a typical 

career. The requirement that baseline climate monitoring stations be sited 

in settings that will remain undisturbed (except for natural successional 

processes) leads to the need for land devoted primarily to research needs. 

Many of the West’s federal agencies have something to offer in this regard. 

The NOAA Climate Reference Network, for example, has attempted 

to take advantage of the natural platforms, automatically protected 

from encroachment, offered by the lands of the National Park Service 

(NPS), with the further advantage of tying in to the NPS Inventory and 

Monitoring Program. Such efforts should be encouraged and expanded.

The NOAA Regional Climate Center (RCC) program has recently 

teamed with the National Weather Service and the National Climatic 

Data Center to develop a distributed infrastructure for ingesting and 

disseminating climate data from various networks. At this writing the 

system now ingests manually observed daily cooperative data supplied by 

Practical considerations lead 

to the clear conclusion that 

there is an enormous need 

for improved coordination 

among a very diverse cast of 

characters. 
30

NWS, and transforms this into temperature and precipitation anomaly 

maps for various periods extending back into the past from a week to 

36 months, updated each day for the nation and for subregions. This 

infrastructure is known as the Applied Climate Information System 

(ACIS) (ACIS 2005, Hubbard et al. 2004, WRCC-CIP 2006 “related 

sites”). Such information is very useful for resource management. 

The National Park Service (NPS) Inventory and Monitoring (I&M) 

Program is an ambitious and comprehensive effort to utilize about 285 

park units as platforms to monitor ecological health in a wide variety of 

settings (NPS 2006, Oakley et al. 2003). NPS has organized 32 groups 

of geographically distributed park units (I&M Networks) to address 

regional aspects. Climate and weather are a major environmental driver 

and indicator in all park units with significant natural resources. Climate 

is being addressed at the network level; for representative examples see 

Oakley and Boudreau (2000), MacCluskie and Oakley (2002, 2003), 

MacCluskie et al. (2004), and Sousanes (2004). The NPS and Western 

Regional Climate Center (WRCC 2006) are collaborating on the 

development of inventories of weather and climate information for each 

of 32 NPS groups of park units (I&M Networks) to help guide future 

activities. This depends heavily on the ACIS structure (WRCC-CIP, 2006, 

“related sites”). Initial emphasis on central Alaska (Redmond and Simeral 

2006) and the Greater Yellowstone ecosystem (Davey et al. 2006) build on 

earlier work for the Channel Islands (Redmond and McCurdy 2005) and 

southwest Alaska (Redmond et al. 2005). The methods, findings, data and 

metadata, web pages, and activities associated with this effort are directly 

relevant to those of many other resource management agencies. 

The highly convoluted topography of the West necessitates mapping 

and descriptive techniques that can resolve individual mountains ranges 

and mountains (e.g., to a mile or less), such as PRISM (Daly et al. 1994, 

2002, 2004), for uses such as ongoing monitoring, quality control of data, 

understanding changing elevational relationships, and the elevational 

details of climate variability and change. Simpson et al. (2005) have 

evaluated different approaches to mapping of climate in regions of 

exceptional topographic relief.

In addition to tracking of the physical elements of climate, measures 

of the consequences and impacts of climate behavior are needed to 

identify and understand how these connect. Efforts to establish a National 

Integrated Drought Information System (NIDIS) must address this 

issue. Monitoring of the impacts of climate is haphazard and very uneven 

(Western Governors Association 2004), with very few systematic efforts. 

NIDIS represents the kind of broadly based activity able to provide a 

common framework and coordination for a wide variety of climate-related 

operational and research needs. Furthermore, the bulk of climate impacts 

are felt at the smaller scales of individuals and businesses, where such 

information is even harder to acquire, manipulate and distill. For such 

work a database of economic impacts is also much needed (Changnon 

2005). 

The highly convoluted 

topography of the West 

necessitates mapping and 

descriptive techniques 

that can resolve individual 

mountains ranges and 

mountains ...for uses such 

as ongoing monitoring, 

quality control of data, 

understanding changing 

elevational relationships, 

and the elevational details 

of climate variability and 

change. 
31

Concluding Remarks

The needs for climate information span a very broad range. The 

National Research Council (2001) laid out the ingredients and attributes 

of a comprehensive program of national climate services, defined after 

careful deliberation over each word as: 

The timely production and delivery of useful climate data, 

information, and knowledge to decision makers.

The key point is that the desired information is centered around 

assisting with some sort of decision, narrow or broad, trivial or 

momentous. Monitoring, data stewardship, active programs of research, 

and the engagement of diverse governmental, academic and private 

communities constitute other essential components, interacting in an 

iterative fashion.

There is an extraordinary amount of information currently “out 

there,” much of it greatly underutilized, often not in a convenient, 

meaningful, or accessible form. The United States Climate Change 

Science Program, currently budgeted at around $2 billion annually, 

and allied efforts, continue to churn out new knowledge about global, 

regional and local climate behavior at a rapid pace. The pipeline between 

knowledge production and use needs to be shorter and wider, to reduce 

the time lag between discovery or observation and application. To 

provide this capacity, there is a great need for trusted and knowledgeable 

information brokers, acting as intermediaries to connect providers and 

users. These individuals must be comfortable and credible within each of 

the respective communities they are attempting to bridge. 

State, regional, and national climate centers have operated in 

this milieu for a number of years. Over the last ten years additional 

institutional structures have arisen, with a special, but not exclusive, 

emphasis on better understanding of the decision environment of users, a 

necessity for effective use of knowledge (e.g., Rayner et al. 2005). A special 

NOAA activity, the Regional Integrated Sciences and Assessments (RISA) 

Program, has made significant headway in this direction. The process is 

long, iterative, nonlinear, organic, and features mutual learning. Four of 

these projects operate in the Western states (RISA 2006). Collectively, 

among all these varied players, there is a significant amount of capability 

waiting to be harnessed. New technologies for sensing, storing, retrieving, 

displaying, and disseminating information offer a great deal of promise.

With all the multiple complexities found in the West in observational 

systems, information repositories, economic sectors, user communities, 

climatic diversity, topographic juxtapositions, and a potential trajectory 

toward a different kind of future, apparently endlessly nested like Russian 

dolls, the whole situation may seem hopelessly complex. However, in spite 

of this appearance, there is also ample evidence to suggest that with care 

and diligence we can nonetheless harness what we know and what is being 

discovered to effectively navigate our way through this maze, and achieve 

satisfactory solutions. To do so simply requires an ability and willingness 

to stretch in new ways on the part of information providers and users alike.

There is an extraordinary 

amount of information 

currently “out there,” much 

of it greatly underutilized, 

often not in a convenient, 

meaningful, or accessible 

form. 

...there is also ample 

evidence to suggest that with 

care and diligence we can 

nonetheless harness what 

we know and what is being 

discovered to effectively 

navigate our way through 

this maze, and achieve 

satisfactory solutions. 
32

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41

Terrestrial and Aquatic Natural Ecosystems: 

Potential Responses to Global Climate Change

Hermann Gucinski 1

1Was an assistant director (retired), USDA Forest Service, Southern Research Station, Asheville, NC 28802.

Erik Ackerson, EarthDesign, Ink

foreground Gary M. Stolz 

U.S. Fish and Wildlife Service

background Erik Ackerson

Olympic National Park
42

Abstract

Evidence that climate is warming is increasingly obvious. Responses 

include the earlier onset of green-up, the displacement of high-latitude 

species by low-latitude ones in both terrestrial and coastal regions, and the 

infilling of alpine tundra by sub-alpine. For the American West models 

and projections of current climate trends show reductions of desert 

and increase in shrubland, except for the great basin, and reduction or 

disappearance of alpine biomes for the 21st century. Already multiple 

stresses influence western ecosystems; climate change is an added stressor. 

Fire frequencies and intensities may hasten ecosystem degradation 

from other causes; vegetation shifts can be accelerated or slowed by fire. 

Invasive species will affect fire regimes and induce positive or negative 

feedback mechanisms. Insects and pathogens, as well as their natural 

predators will change in numbers, population dynamics and areal extent. 

Resource systems are not static, with climate change their dynamism 

may be accelerated. This changes how we approach conservation reserves, 

view development at the wildland-urban interface, think about habitat 

and future migration corridors. Seed dispersal, the role of pollinators, 

influence of topographic and human constraints to migration, and 

conflicting demands between community, agricultural and aquatic system 

water needs will require new thinking over multiple organizational levels.

Keywords: Climate changes, ecosystems responses. 

Introduction

Natural resource managers of today face an uncertain world that 

poses many challenges, among them the threat of invasive species, fuel 

accumulations and risk of catastrophic fire, alteration and loss of habitat, 

encroachment from human development such as urban expansion, and 

the interaction of processes that produce difficult to predict synergistic 

effects. Managers have further come to realize that to that plethora 

must be added the risk of potential climate change and altered climate 

variability. How ecosystems will respond to these added stressors, and 

how these might play out with the other impacts is of concern when it has 

become apparent that attaining sustainability in the delivery of goods and 

services from natural systems can at times appear a losing proposition. 

In this paper we will attempt to describe the current knowledge of 

ecosystem responses to climate change and variability in the American 

West and explore the implications managers may wish to be aware of both 

from the short-term tactical perspective and from the long-range, policy 

position. It is a foregone conclusion that uncertainty and the framework 

within which to manage in an uncertain world will be a significant part of 

the problem, and it is hoped some helpful hints will be found here.

The scope of this paper, in addition to limiting itself to the American 

West, is to touch on topics that were insufficiently advanced for 

consideration 4 years ago when the National Assessment was completed. 

...will attempt to describe 

the current knowledge 

of ecosystem responses 

to climate change and 

variability in the American 

West and explore the 

implications managers may 

wish to be aware of...
43

We will analyze several broad areas from the perspective of the added 

risk of climate change and variability in relation to ecosystem response: 

a. Vegetation re-distribution ranging from the biome to the species 

level

b. Fire-affected processes

c. Aquatic ecosystems

d. Biodiversity impacts, disturbance and invasive species

e. Multiple interactions and feedbacks

Finally, we will make some recommendations that reflect the implications 

of the advances in recent learning. 

Background

The concept that man-made releases of CO2 could alter climate 

goes back to some very early thinking by Arrhenius (1896, cited in the 

National Assessment 2001) and was given more substantive thought in 

the late 1950s by Roger Revelle (Revelle and Waggoner 1984). Revelle’s 

hypothesis led to experimental verification that CO2 was rising in the 

earth’s atmosphere by Keeling and Whorf (1999), whose measurement 

record at the Mauna Loa dates back to 1958. The interpretation of choice 

by atmospheric scientists is that radiative forcing produced by additions 

of “greenhouse” gases to the atmosphere is the driver for climate change. 

Greenhouse gases (water vapor is the most potent among them) absorb 

energy within the solar spectrum, and that energy “capture” leads to a 

rise in temperature, ultimately balanced by emission of radiation at much 

lower wavelengths. 

However, changes in radiative forcing alone do not tell the whole 

story of climate change. We must also take into account the processes 

that take up and redistribute energy (such as changes in the atmospheric 

moisture and the storage capacity of oceans), and interchanges between 

these reservoirs and the biosphere. Coupled ocean-atmosphere physics 

models have grown in sophistication and account for most of the known 

processes. However, the complexity a multitude of variables, and a certain 

degree of stochasticity, permits the models to provide predictions at 

continental scales, but not regional ones. This is shown by the divergence 

in results of different GCMs (Global Circulation Models). Nevertheless, 

the confidence level for global interpretation has continued to rise; in 

fact, a group of National Science Academies, representing 16 countries, 

say: “We support the IPCC’s—Intergovernmental Panel on Climate 

Change—conclusion that it is at least 90 percent certain that temperatures 

will continue to rise, with average global surface temperature projected to 

increase by between 1.4 and 5.8°C above 1990 levels by 2100” (Gucinski 

et al. 2004, excerpted therein from HYPERLINK "http://www.royalsoc.

ac.uk/files/statfiles/document-138.pdf").

For insights regarding the ecosystem responses to climate change, 

the inadequacy of regional-scale predictability has lead scientists to 

consider a second approach. Here, trends within the period of record for 

meteorological observations (a little over a century) are extrapolated over 

The interpretation of choice 

by atmospheric scientists 

is that radiative forcing 

produced by additions of 

“greenhouse” gases to the 

atmosphere is the driver for 

climate change. 
44

the next few decades; in many cases this is generally consistent with GCM 

model runs for the same period, but perhaps allows greater insight into 

events at the regional scale. 

The dichotomy can be usefully employed in examining ecological 

responses. One may build ecological models driven by the climate 

scenarios—using several GCM outputs, a "fix" is derived for the range 

of possible responses—and analyze the most likely trends in ecosystem 

behavior. Alternatively, one can use empirical extrapolation from observed 

ecosystem function. Given the current level of understanding, the safest 

approach is to employ both methods and use the contradictions, real or 

apparent, to refine and improve the science, as was done in the National 

Assessment (2001).

State-of-Science by 2000

The state of science up to the year 2000 can be found in the “Climate 

Change Impacts on the United States” effort (NAST or National 

Assessment Synthesis Team 2001) and a series of papers that are derived 

from it, such as Aber et al. (2001), Dale et al. (2001), Hansen et al. 

(2001); we will recap its major conclusions for the American West. 

The assessment team used the two broad approaches mentioned 

above, extrapolating the historical records and using general circulation 

model simulations to assess the climate change effects. In the former 

approach, direct observations of temperature and precipitation for the 

past 100 years were supplemented by space-based observations, along 

with paleoclimate surrogate data inferred from tree ring, sediment, ice 

core and related proxies. In the National Assessment sensitivity studies 

that examine ecosystem impacts were taken from VEMAP (VegetationEcosystem Modeling and Analysis Project, Kittel et al. 1997) used to 

supplement the historical data. 

The 20th century climate simulations show general agreement for the 

U.S. data as a whole, are a bit warmer than observations along mountain 

ridges such as the Sierra Nevada and Cascade Mountains, colder over 

mountain basins, and diverge even more over the southern Rocky 

Mountains and Great Basin. Direct model outputs must be modified, or 

modeled further to arrive at secondary information such as soil moisture 

and snow pack extent and depth, or extrapolated to provide a measure 

of changes such as the nature of precipitation events, or the likelihood of 

temperature extremes or other extreme events.

With these inputs, the National Assessment Synthesis Team and 

Wagner (2003) concluded the following regarding global climate change 

and variability and potential ecosystems responses for the West:

• Where wetter conditions are likely, we can expect an increase in 

vegetative biomass and a reduction in desert area. In the Pacific 

Northwest, average increases in precipitation were 11 percent for 

the 20th century, with the far northwestern region experiencing as 

much as a 50 percent increase. The northwest is additionally subject 

to cyclical changes strongly correlated to El Niño/La Niña and the 

Direct model outputs must 

be modified, or modeled 

further to arrive at secondary 

information such as soil 

moisture and snow pack 

extent and depth...
45

Pacific Decadal Oscillation (PDO). These cycles tend to correlate 

warm temperatures with summer drought, and cool temperatures 

with wetter winters. At the time of publication of the assessment, 

little was known about how such pattern will be affected by altered 

climate. Using GCM scenarios for the relative small size of the 

Pacific Northwest region is made problematic by the coarse grid cells 

of the GCMs, few grid cells cover the northwest, and the montane 

topography add further complications due to elevation difference 

effects.

• Where reduced precipitation is expected, as in areas of southwestern 

Arizona, the opposite is likely, i.e., forest productivity may decline 

and desertification increase. In either case, increases in forest fire 

frequency are possible.

• Biodiversity is already impacted by habitat fragmentation, increases 

in migration barriers and invasive species. It will likely decline 

further with climate change as an added stressor. While some species 

may be able to migrate to higher elevations, habitats specific to high 

elevations now may disappear. Adaptive strategies having the most 

promise for implementation include lessening the impact of rural 

development and consciously removing existing migration barriers 

and preventing new ones from arising.

• Aquatic systems are likely to be impacted by the reduction of 

snowpack extent due to warming, which may offset scenarios 

of increased precipitation. Earlier melting and changed run-off 

intensities could alter hydrographs significantly, affecting spawning 

and altering stream habitat. For example, in the northwest, clear 

correlation between salmon abundance and climate exists for the 

freshwater portion of their life cycle, which includes spawning, of 

course, and here, potential summer warming and reduced summer 

stream flow will be negatives. In regions of lessened precipitation 

increased competition for water resources could impact stream 

productivity and reduce available habitat for aquatic organisms. 

Means for using technological approaches to mitigate these 

impacts are available and could be applied if policy for such steps is 

promulgated and accepted.

Examples from the NAST (2001) Selected 

to Conveythe Scope of the Impacts:

In a quantitative estimate of climate change impacts on runoff for 

selected western basins (taken NAST 2001), the authors note that where 

runoff remains the same or is reduced, added stresses to stream habitat 

can be inferred from increased temperatures, with attendant reductions in 

dissolved oxygen levels, particularly in slow-flowing systems (table 1). 

They note further that in montane areas, significant temperature 

rise may put alpine, coldwater species at risk of extinction. Increases in 

runoff will have varying effects, depending on the extent of accompanying 

changes in the hydrograph; flashier flow regimes are likely to produce 

negative changes while well-distributed ones could be beneficial. 

Biodiversity is already 

impacted by habitat 

fragmentation, increases 

in migration barriers and 

invasive species. It will likely 

decline further with climate 

change as an added stressor.

...in montane areas, 

significant temperature rise 

may put alpine, coldwater 

species at risk of extinction.
46

Alteration in habitat characteristic can drive competition among species, 

change dominance patterns, and drive some toward extinction (this 

applies to more than aquatic systems). A confounding factor here is 

the competitive advantage that permits introduced species to thrive, 

exacerbating biodiversity issues.

Large regions of the American West are covered by fire-prone 

vegetation; these ecosystems have evolved adaptations to survive these 

conditions. The appearance of humans has at times upset that balance, 

such as when reforestation has lead to denser tree growth, inviting more 

crown- and stand-replacement fires, or where human development in 

wildland areas took no heed or precautions to fire risk. The introduction 

of xenobiotics (foreign invasives) has further exacerbated the problem. 

Where climate warming leads to increased evapotranspiration, increased 

fire frequency may result, and increased precipitation may not routinely 

reduce fire risk. The latter is likely where the increases in precipitation 

occur in winter months, but leave summer drought unchanged, 

which is typical for much of the Far West. For example, the dynamic 

ecosystem model MC1, using both Hadley (HadCM2) and a Canadian 

GCM (CGCM1), shows a gradual trend of increasing forest biomass 

consumption by fire and greater consumption for single year events 

(catastrophic fires), with the Hadley scenario appearing somewhat more 

benign (Bachelet et al. 2001). There have been several new studies 

to provide further insights into these dynamics, along with increased 

emphasis on understanding the interaction between multiple ecosystem 

changes, and these will be considered in the next section. 

The direct effect of atmospheric carbon increases, sometimes seen as 

“fertilization” that enhances forest productivity, has remained elusive for 

the writers of the National Assessment. The initial responses of increased 

CO2 seen in chamber and other exposure studies were only maintained 

under conditions of adequate water and nutrient availability. Otherwise 

a down-regulation by trees resulted, leading to only small and variable 

increases in forest productivity (Orem et al. 2001). But the data were not 

yet conclusive at the time of writing.

In the next section we will attempt two things: one, to bring the 

insights of new studies, experiments and modeling efforts to bear; and 

two, to attempt to synthesize the state-of-science findings based on the 

interaction of multiple variables, of which climate change and climate 

Region Historical

runoff Change in annual runoff

1961-1990 2025-2034 (mm/y) 2090-2099 (mm/y)

Upper Colorado 43 -15 3 2 28

Lower Colorado 2 -1 6 0 33

Great Basin 21 -1 4 16 29

California 232 60 63 320 273

Table 1—Current and estimated changes in runoff from CGCM1 and HadCM2

Large regions of the 

American West are covered 

by fire-prone vegetation; 

these ecosystems have 

evolved adaptations to 

survive these conditions. The 

appearance of humans has 

at times upset that balance, 

such as when reforestation 

has lead to denser tree 

growth...

The direct effect of 

atmospheric carbon 

increases, sometimes seen as 

“fertilization” that enhances 

forest productivity, has 

remained elusive...
47

variability are but two elements. Throughout, we will hark to “the big 

picture” that we believe is of greater relevance to the resource manager 

than a host of details, many of which may be contradictory.

New Insights into Climate Change and the 

Potential Range of Ecological Responses

Climate Change

Examining specific developments in climate science itself goes beyond 

the scope of this paper, and will be addressed in a parallel effort. Our 

interest here is in understanding how progress in the climate science 

arena has benefited analyses of ecosystem, hydrologic/aquatic and related 

responses.

We will digress briefly, however, to broach a topic that received only 

the merest mention in the National Assessment, and one that may be 

relegated to the topic of “climate surprises.” That is the possibility of 

global cooling triggered by the temperature rise at high latitude. A recent 

Pentagon study (Schwartz and Randall 2003) forcefully calls attention 

to the need to plan for such a scenario. A subsequent comprehensive 

review done by Clark et al. (2002) re-states the importance of the ocean’s 

thermohaline circulation (THC) in redistributing the globally uneven 

input of solar atmosphere. The thermohaline circulation is the density 

driven movement of ocean water, fresh or warm water will tend to stay on 

top, salty or cold below. However, very cold water such as formed in some 

polar regions, will sink and displace water below, this leads to exchange 

of deep waters and helps balance energy input differences between the 

northern and southern hemisphere. This interaction is complex and has 

added uncertainly in general circulation models. Recently obtained proxy 

records (radionuclide ratios in ice cores) show that the thermohaline 

circulation has collapsed several times over millennial time scales. The 

THC is driven in part by the formation of Atlantic deep water by sinking 

of surface water near Greenland (the Irminger Sea and Davis Strait areas). 

In past ice-ages, the THC has been interrupted because a fresh water lens 

is formed by increased melting of the Greenland ice cap (for a discussion 

of the value and need to use multiple proxy records, see Mann 2002 

and for a discussion for statistical approaches to quantify climate model 

uncertainties, see Katz 2002). Coupled atmosphere-ocean GCMs are 

known to have several equilibria that reflect the altered thermohaline flow. 

This, and the relationship between the circulation status and cold periods 

like the Younger Dryas, as well as additional recent modeling, appear to 

point to the potential for a modest increase in freshwater runoff leading 

to a significant decrease in North Atlantic density driven flow. That could 

produce the cooling that has occurred historically (on geologic time 

scales) and has come about abruptly. Hansen (2005) points out in a recent 

editorial that glacial retreat and melting proceeds at a far more accelerated 

rate than does accretion, in large part because of positive feedback loops 

that come into play, and examines critical points in the melting regime 

that could lead to abrupt change—he warns that a “business as usual” 

scenario for man-made climate change could quickly take us to such 

a point.

...glacial retreat and melting 

proceeds at a far more 

accelerated rate than does 

accretion, in large part 

because of positive feedback 

loops that come into play...

critical points in the melting 

regime that could lead to 

abrupt change...
48

The above serves as an added dimension to examine the spectrum 

of possible ecological responses. While we cannot as yet translate this 

emerging thinking into recommendations for resource managers, we shall 

return to this when discussing management in a climate of open-ended 

uncertainties.

There is a rapid and increasing accumulation of observations of 

consequences of the current warming trend. We will not attempt to cover 

the climatological data records, instead focusing on observed ecosystem 

and related responses, but wish to cite one review paper in order to 

address briefly the continued controversy regarding extreme climate 

events. Easterling et al. (2000) state that recent model studies further 

strengthen earlier outputs, that we can expect more intense precipitation 

events and increased summer drought, and that the future climate could 

resemble El Niño years more often. While there is poor agreement 

between GCMs on large storm intensity and frequency, work with nested 

models suggest that there will be increases in surface wind speeds and a 28 

percent increase in near-storm precipitation. Unfortunately, the current 

level of scientific analysis has not yet allowed breaking out particulars for 

the Western United States. 

Ecosystem Responses

Vegetation Redistribution at the Biome and Species Level

We now return to the more commonly accepted climate change 

scenarios of global warming. We begin with a discussion of vegetation 

change in response to climate forcing. The observational evidence since 

the National Assessment continues to give instances that match the trend 

previously reported (Iverson and Prasad 2001, Julius et al. 2003). In their 

report on a longitudinal transect (CLIMET) from the Olympic Peninsula 

in Washington State to Montana, Fagre et al. (2003) note the continued 

reduction of alpine tundra due to the replacement by sub-alpine forest. 

They caution that the process is not linear and not simply elevational, 

but appears to favor areas such as avalanche paths and infilling, and has 

aspect-dependent differences. However, upward migration has been 

observed to reach as much as 250 m in elevation. By contrast, elevational 

changes during the Holocene appear to have been generally less than 100 

m. Accompanying the sub-alpine forest expansion is the glacial retreat. 

Glacier National Park had 150 glaciers in 1850; today 37 remain. Glacial 

ice thickness has decreased along with the retreat, as determined by use of 

ground penetrating radar. Simple extrapolation of this pattern could lead 

to the disappearance of the park’s glaciers as early as 2030 (see references 

within Fagre et al. 2003). Lastly, the authors note that high elevation 

forest productivity has risen when compared to that of lower elevation 

forest. In Mexico, the drought of the 1950s led to changes in the pine to 

pinion-juniper forest up to 5 km, and these shifts have not reversed to the 

present time, though the drought abated (Easterling et al. 2000).

A full understanding of the relationship of climate to ecosystem 

productivity and processes will not come from observational evidence 

alone. To test one’s understanding, models can provide considerable 

Glacier National Park 

had 150 glaciers in 1850; 

today 37 remain. Glacial 

ice thickness has decreased 

along with the retreat...

Simple extrapolation of this 

pattern could lead to the 

disappearance of the park’s 

glaciers as early as 2030...
49

opportunity, and, once sufficiently robust and grounded in dominant 

physiological and biochemical mechanisms, can have predictive value. 

Lacking that, the models can deliver insight for potential scenarios that 

may delineate the range of potential ecosystem responses.

The National Assessment delineated ecosystem responses by 

considering both a biome-level, biogeographic—essentially, a life zone 

approach—to vegetation distribution. This approach has been developed 

further to incorporate hydrology, such as the equilibrium model 

MAPSS (Neilson 1995) and the MC1 model [the latter is dynamic and 

incorporates biogeography, biogeochemistry and fire dynamics (Bachelet 

et al. 2001, Daly et al. 2000, Lenihan et al. 2003)]. These models have 

continued to be used and refined, as has species-specific work relying on 

the development of response surfaces from empirical consideration of 

species requirements, as will be explained below.

Bachelet et al. (2001) used both MAPSS and MC1 to simulate 

vegetation distribution for historical climate and future scenarios, 

and to determine changes in leaf-area index (LAI) and changes in 

areas of stress as reflected by reduction in vegetation density for the 

conterminous United States. Their approach compares the two models, 

which can inspire confidence where good agreement is observed, or 

invite improvement where differences remain. In more recent work, 

the Canadian GCM (CGCM1) and the British Hadley Centre model 

(HadCM2) have principally been used; these agree in positing a slight 

conifer forest expansion. Figure 1 is a coarse scale representation of that 

expansion, done for both GCMs. 

Model outputs further show shrubland losses in the Great Basin; 

farther west, they show reductions in desert area, i.e., increased shrubland 

biomass, due to the increased precipitation. Under increased warming the 

cold tolerant, high elevation alpine tundra, and even some sub-alpine trees 

may have nowhere to climb and disappear. The fate of western coniferous 

forests is of great interest, and here the models leave room for speculation. 

One model, MC1, posits an increase in forest area, but accompanied by 

decreased biomass (as reflected in carbon stores) in their present range, 

while the other, MAPSS, posits little areal change, but yields a decrease in 

LAI (i.e., a loss of productivity). In other words, the expanding forest may 

have a savannah-like structure.

Another interesting concept included in the simulations by Bachelet 

et al. (2001) is that of the stressed area as the fraction of the total land 

surface under consideration where a decline in vegetation density occurs. 

The simulation of historical climate shows the 1930s drought, which 

affected 49 percent of U.S. forested area and 60 percent of the land area, 

and also shows the 1972 climate shift toward wetter conditions. The sharp 

difference between the models’ stress index for future climates reflects 

differences in the GCMs, when comparing the Hadley with the Canadian 

model. Such divergence reflects interpretation of large-scale atmospheric 

behavior in the GCMs, which are influenced by such factors as the 

positioning or shift in summer high-pressure fields such as the Bermuda 

High, or differences in the location of the jet stream. 

Under increased warming 

the cold tolerant, high 

elevation alpine tundra, and 

even some sub-alpine trees 

may have nowhere to climb 

and disappear.
50

There are, as yet, no a priori considerations that allow either an 

atmospheric physicist or a layperson to accept or reject one scenario 

over another. Hence, the resource manager will face a wider spectrum 

of uncertainty. The implications of these findings will be taken up 

subsequently.

The conclusions of the above work are amplified by a more refined 

analysis applied by Lenihan et al. (2003) to California. Based on the 

use of the same two GCM (Canadian and Hadley) above, their results 

show similar vegetation dynamics, such as the shift in dominance of 

needle-leaved to broadleaved forests, accompanied by increases in 

productivity. Additionally, their work serves to highlight the role of fire 

in these ecosystems. Fire dynamics are not only altered by annual as 

well as seasonal trends in precipitation, but may initiate feedback loops 

to strengthen emerging trends. For example, the Modoc Plateau in 

northern California, now dominated by shrubland-conifer vegetation, will 

experience reduced precipitation that allows ingress of grass species. The 

fine fuel flammability will lead to higher fire frequencies, which serves to 

Figure 1—Conifer expansion in the American West under future climate shown as a DIFFERENCE map 

from current climate for a) the HadCM2 GCM and b) the Canadian GCM (CGCM1) scenario (courtesy 

of D. Bachelet, Oregon State University).

b.

a.

Legend

Alpine Tundra

Temperate Deciduous Forest

Conifer Forest

Grassland

Savanna/Woodland

Shrubland/Woodland

Fire dynamics are not 

only altered by annual as 

well as seasonal trends in 

precipitation, but may 

initiate feedback loops to 

strengthen emerging trends.
51

discourage tree/shrub recovery, solidifying the competitive advantage of 

the grasses. One somewhat ironic effect is that the wetter climate under 

the Hadley scenario can increase fire frequency or severity. California is 

influenced by the cyclical nature of both short-term events such as El 

Niño/La Niña cycles and the longer term PDO. Wet years will permit 

greater productivity and hence greater fuel accumulation. The following 

dry cycle will not only lead to higher ignition rates, but to more intense, 

and possibly more extensive fires because of fuel availability.

Although the simulations of MAPSS and MC1 yield potential 

redistribution of major biome components such as forest, savannas, 

shrublands or deserts, they say nothing of species. Yet the response of 

vegetation will be borne at the species level, under a multiplicity of 

reactions that include species-specific responses in productivity, root-shoot 

carbon allocation, competitive interactions, seed dispersal mechanisms, 

influence of soils, herbivory, pollination, and so on. This will affect plant 

behavior in situ as well as the plants’ ability to new habitats.

Current efforts at predicting species-based vegetation response rely 

on empirical bioclimatic correlations. For example, Shafer et al. (2001) 

use the mean temperature of the coldest month of the year, growing 

degree days, and a moisture index to derive “response surfaces” that reflect 

the “exploitable” habitat for a given species. However, the treatment of 

these response surfaces allows imposition of future climate scenarios 

and can be used to infer new zones of species “habitability.” The results 

are instructive. Selected species relevant to the West include Douglas-fir 

(Pseudotsuga menziesii (Mirbel) Franco), Ponderosa (Pinus ponderosa P.& 

C. Lawson), Pacific yew (Taxus brevifolia Nutt.), big sagebrush (Artemisia 

tridentate Nutt.), Saguaro (Carmegiea gigantean (Engelm.) Britt. & Rose), 

and creosote bush (Larrea tridentate (Sessé & Moc. ex DC.) Coville). 

Response surfaces can be generated for future climate using GCM 

scenarios. In general, the authors report that resulting species shifts 

are potentially large—hundreds of miles—in all three GCM scenarios 

used (CGCM1, HadCM2, and CSIRO [Commonwealth Scientific and 

Industrial Research Organization, Australia]). The actual patterns of 

the shifts are affected by topography, and are not simply a northward or 

upward expansion as warming only would suggest.

In the northwest, higher coldest month temperature may lead to a 

contraction of Pacific silver fir (Abies ambilis (Dougl. ex Loud.) Dougl. 

ex Forbes) habitat. Interestingly, the authors report a shift eastward of 

species typical of the west-side mountains of Oregon and Washington; 

these species include Douglas fir, Pacific yew, as well as red alder (Alnus 

rubra Bong.) and Oregon white oak (Quercus gerryana Dougl. ex Hook.). 

Conversely, drought tolerant species such as Ponderosa will shift westward 

across the crest of the Cascades. Big sagebrush, a cold steppe component, 

will shift northward, but also contract from its current range, presumably 

driven by summer moisture stress, which in part limits its southern range. 

At the same time, both saguaro and creosote bush will expand into some 

of the present range of big sagebrush, and saguaro could expand both east 

and westward from its current distribution.

Wet years will permit greater 

productivity and hence 

greater fuel accumulation. 

The following dry cycle 

will not only lead to higher 

ignition rates, but to more 

intense, and possibly more 

extensive fires because of 

fuel availability.

...drought tolerant species 

such as Ponderosa will shift 

westward across the crest of 

the Cascades. 
52

These simulations do not take into account limiting factors such 

as barriers to migration, seed dispersal issues, absence or lessening 

fire frequency effects on species requiring fire-hardening (e.g., having 

serotinous cones), and isolation of habitats or their fragmentation. The 

final distribution of species from such changes may be quite different than 

their potential range would indicate. One may surmise that periods of 

instability will create opportunities for invasive species where none exist 

now, further complicating predictions. Lastly, the simulations will be 

reliable to the extent that average temperature of coldest month, growingdegree days and moisture stress can be used to explain the principal 

response of the species examined; there may be cases where adaptation or 

other variables modify responses.

Fire

We have already mentioned the role of fire in western ecosystems, 

the conclusions regarding fire in the National Assessment, and the firevegetation interaction reported by Lenihan et al. (2003) for California. 

Figure 2 shows the simulation for both current and future climate. Fire 

alters the landscape, changes the vegetation patterns, affects succession, 

alters, and is altered by, invasive species. Understanding the effects of 

potential climate change includes understanding direct changes on present 

vegetation, vegetation-fire feedbacks, and fire regimes under vegetation 

shifts. Between 1989 and 1998, an average 100,000 fires consumed forests 

on 3.3 million acres per year in the United States. There is, of course, 

great variability (Flannigan et al. 2000); Whitlock at al. (2003) state that 

the paleo-record shows the fire-climate relationship quite clearly, they 

suggest that 20th century fire histories in the West portray a situation of 

“fire scarcity” when compared to the paleo-ecological record; it could be 

that the present-day fire regimes may be more ephemeral than previously 

thought. 

Resource managers would like to know how fire regimes will change 

in both the near term, e.g., the next decade or two, and over the longer 

stretch, when the doubling of CO2 might be expected. Fire danger is 

measured in several ways; indices have been developed to express differing 

aspects. Flanagan et al. (2000) used seasonal severity ratings (SSR), 

an index commonly used by fire managers that describes the seasonal 

average of the daily estimate of fire control difficulty. This measure can 

be projected using GCM outputs, and the authors state that both models 

(CGMC1 and HadCM2) show a 10 percent or less increase in SSR in the 

west.

More detailed is the work of Brown et al. (2004), who have used 

the Energy Release Component (ERC) to investigate climate change 

responses. The ERC (measured as heat energy per unit area) relates to fire 

severity, the higher the ERC, the more likely that a hot fire will grow and 

be hard to contain. The ERC is strongly influenced by relative humidity, 

which in turn affects fuel moisture. This relationship is quantified using a 

fuel model; climate model outputs, including humidity and temperature 

are inputs to the fuel model, which, combined with fuel abundance 

data, can be used to calculate ERC numbers. The model is calibrated 

...periods of instability 

will create opportunities 

for invasive species where 

none exist now, further 

complicating predictions. 

Fire alters the landscape, 

changes the vegetation 

patterns, affects succession, 

alters, and is altered 

by, invasive species. 

Understanding the effects 

of potential climate change 

includes understanding 

direct changes on present 

vegetation, vegetation-fire 

feedbacks, and fire regimes 

under vegetation shifts. 
53

by running it for historical periods for which ERC values have been 

determined independently, and then future scenarios are derived.

Brown et al. (2004) report on the Parallel Climate Model developed at 

NCAR (National Center for Atmospheric Research, Boulder, Colorado), 

which differs from those mentioned earlier. Using this model, they predict 

a drying trend, with more days of lower humidity compared to the 

present, for the Great Basin and the desert southwest. They arrive at an 

ERC threshold value of 60, a value presently reached at certain points in 

the fire season; Figure 3, taken from their work, shows the change in mean 

Figure 2—California vegetation change for 2 global circulation model (GCC) scenarios, a) current and 

simulated distribution, and b) future distribution using the Parallel Climate model (PCN), top, and 

Hadley (HadCM2), bottom, models (Lenihan 2003, by permission).

Alpine/subalpine forest

Evergreen conifer forest

Mixed evergreen forest

Mixed evergreen woodland

Grassland

Shrubland

Desert

a. b.

Alpine/subalpine forest

Evergreen conifer forest

Mixed evergreen forest

Mixed evergreen woodland

Grassland

Shrubland

Desert

a. b.
54

number of days when the energy release component exceeds 60 for four 

future decades, based on parallel climate model runs. At that threshold, 

fires have historically reached large proportions (> 40 ha), been difficult 

to control, and required a large containment effort, i.e., been expensive to 

fight. The Western United States is strongly affected by bidecadal climate 

patterns and the influence of these patterns can be seen in the predictions. 

The predicted threshold ERCs are reached 2 weeks earlier in the fire 

season in the Southwest, and earlier than at present nearly everywhere 

in the West, especially in the Great Basin and the northern Rockies, 

excepting the Front Range and High Plains. Neither group was able to 

include the effects of potential vegetation shifts, as theirs was a first-cut 

approach.

Added to potential vegetation shifts is the appearance of exotic 

species. These may not only alter the success rate of such shifts, outcompete native species, but influence fire with feedback mechanisms. 

Brooks at al. (2004) cite examples of both positive feedback—for 

example, the alien grass Bromus tectorum invades shrub steppe areas; 

by its creation of fine fuels it increases not only fire frequency, but the 

length of the fire season because fine fuels can dry out quickly—and 

negative feedback. The latter has been observed in maritime southwestern 

chaparral invaded by a South African succulent, Carpobrotus edulis, which, 

having a higher moisture content, reduces fire intensity. In both cases, the 

change enhances the competitive status of the invader, altering ecosystem 

properties, including herbivore status and their dependent predatorprey relationships. Brooks at al. (2004) develop a schema (fig. 4, taken 

Figure 3—The change in mean number of days when the energy release component (ERC, see text for 

explanation) exceeds 60 for four future decades, based on PCM (parallel climate model) runs (Brown et al. 

2004, by permission).

48°N

46°N

44°N

42°N

40°N

38°N

36°N

34°N

32°N

48°N

46°N

44°N

42°N

40°N

38°N

36°N

34°N

32°N

48°N

46°N

44°N

42°N

40°N

38°N

36°N

34°N

32°N

125°W 120°W 115°W 110°W 105°W 100°W 125°W 120°W 115°W 110°W 105°W

125°W 120°W 115°W 110°W 105°W 100°W 125°W 120°W 115°W 110°W 105°W 100°W

48°N

46°N

44°N

42°N

40°N

38°N

36°N

34°N

32°N

48°N

46°N

44°N

42°N

40°N

38°N

36°N

34°N

32°N

100°W

48°N

46°N

44°N

42°N

40°N

38°N

36°N

34°N

32°N

...the alien grass Bromus 

tectorum invades shrub 

steppe areas; by its creation 

of fine fuels it increases not 

only fire frequency, but the 

length of the fire season 

because fine fuels can dry 

out quickly...
55

from their paper) for understanding the invasive plant fire-regime cycle 

with a four-phase conceptual model. Phase one, invasive plant potential 

depends on the life history and preadaptive status of the invasive in 

relation to the existing fire regime. Phase two, the establishment phase, 

addresses propagule characteristic, dispersal opportunities and barriers 

and related factors required for self-perpetuating populations. Phase 

three occurs when invasive populations reach a size sufficient to alter 

native community composition and functioning. The final phase is the 

one where the presence of the invader alters the fire regime, providing 

the feedback mechanism that effectively ends or greatly reduces the reestablishment potential of the native dominants. We cite this conceptual 

scheme, because it enables the resource manager to conceptualize more 

easily how and when to combat the invaders, and conveys a sense of 

how effective, or expensive, such measures might be. One compelling 

thought—one that comes as no surprise—is that prevention of initial 

introduction is probably the most cost-effective step that can be taken. 

However, managing fuel loads and ignitions are other actions that may 

hold promise once a manager is confronted with the growing presence of 

the invader. Of course, success is not easy to guarantee and may require 

manual native plant re-establishment efforts as well—hard to contemplate 

when resource budgets are scarce and manpower is limited.

Figure 4—A system to evaluate the effects of invasive species and prioritize them for several stages of the 

fire regime cycle. (Brooks et al. 2004, by permission).

Phase 1

Plant species has not

been introduced to the

region of interest.

Phase 2

Plant species is naturalized 

or invasive but has not 

yet caused significant 

ecological impact.

Phase 3

Plant species has had

significant ecological 

impact but has not yet

changed the fire regime.

Phase 4

Plant species has 

changed the fire regime,

establishing an invasive

plant-fire regime cycle.

Evaluate its potential to naturalize, become invasive, 

cause ecological impact, and alter fire regimes.

Prioritize for exclusion of the species from the

management unit.

Evaluate its potential to have significant ecological 

impact, especially by altering fuel structure.

Prioritize for exclusion or control of the species.

Evaluate its potential to alter fire regimes.

Prioritize for control of the species, revegetation of

preinvasive plant populations and communitites, and

restoration of preinvasive ecosystem properties.

If eradication

is successful

If revegetation/

restoratoion is

successful

If fire regime

restoratoion is

successful

Evaluate its potential for the altered fire regimes to

have serious negative effects on natural resources,

local economies, or public safety.

Prioritize for control of the species and restoration

of the preinvasive fire regime.

...this conceptual scheme...

enables the resource 

manager to conceptualize 

more easily how and when 

to combat the invaders, 

and conveys a sense of how 

effective, or expensive, such 

measures might be. 
56

River Flow and Some Implications 

for Aquatics Systems

In order to understand the responses of aquatic ecosystems to climate 

change, one needs to understand how climate affects the hydrology of 

streams, rivers, and lakes. It appears there has been more progress in 

hydrology research than in the biological components. This may be a 

reflection of the state-of-science in both fields. We begin a brief review of 

the former.

An interesting development has been “downscaling,” an attempt to 

take outputs of GCMs, which operate at a coarse scale (grid cells measure 

about 90 miles on edge), and use them as inputs to mesoscale models; 

the much higher resolution of the latter then provide input for yet finer 

scale hydrologic models (Barnett et al. 2004). Leung et al. (2004) used 

the NCAR Parallel Climate Model (PCN) to drive the accepted mesoscale 

MM5 model (40 km spatial resolution), which in turn provides the 

input for the hydrologic simulations. Using the Columbia River and the 

Sacramento-San Joaquin River basins, the author’s simulations suggest 

that the 1 to 2.5°C warming from projected climate change will be greater 

on warm days, and less so on cold days (Payne et al. 2004, Van Rheenen 

et al. 2004). There will also be a strong effect on winter snowpacks, 

leading to a 60 to 70 percent reduction in the coastal mountains of these 

basins, and a 15 to 20 percent cold season increase in daily precipitation. 

This will be accompanied by an increase in rain-on-snow events—these 

are the events that frequently give rise to flooding episodes—and a shift 

of the snowmelt peak from May to April for many portions of the basins. 

The simulations show that during winter months in the Cascades and 

Sierras, daily precipitation will increase 15 to 20 percent, and 15 to 30 

percent in the northern Rockies. Conversely, extremes in precipitation will 

be reduced in the southern portions of the Sierras and Oregon’s coastal 

reaches, consequently snowpack reductions reach as much as 60-70 

percent, which appears to be the effect of temperature varying about the 

freeing point. In areas now normally colder, the increase in temperature 

does not reach the freezing point; impacts on snowpack are much less. 

The predicted snowpack reductions and earlier melt, also reported by 

Stewart et al. (2004) for the Western United States in the same issue, 

will lead to diminished soil moisture in summer. Runoff increases by 

40 percent for the December through February winter months, and is 

reduced by 28 percent for the March through April period. The reduced 

summer moisture appears to contradict the greater precipitation reported 

for northern California by the Hadley GCM (HadGCM2), which shows 

that the simulations have not yet converged to give the resource manager 

a simple picture of what the future holds. Finally, the authors assert that 

the climate-change-induced temperature rise in these regions points to a 

positive snow-albedo feedback enhancing the rise. Their claim makes sense 

from a physics standpoint, but was not well supported in their paper.

Christensen et al. (2004), also starting with the PCM, report a 

much similar result for the Colorado River Basin. They evaluate their 

simulations by giving results for the historical period and the future 

The simulations show that 

during winter months in the 

Cascades and Sierras, daily 

precipitation will increase 

15 to 20 percent, and 15 to 

30 percent in the northern 

Rockies. 
57

scenario, thus they report a 10 percent reduction in basin-wide runoff 

for the historical period, and a 14, 18 and 17 percent reduction for 20-

year periods beginning in 2010. Water storage is simulated at 7 percent 

less than the historic record, and 36, 32 and 40 percent less for the same 

future decadal intervals. 

These simulations set the stage for examining aquatic ecosystem 

responses. The literature for these responses is not as systematic as one 

might wish; some speculative papers appeared a decade or more ago (e.g., 

Gucinski et al. 1990). The aquatic habitats and the fauna adapted to 

present ecosystems will be much influenced by the periodicity of runoff, 

such as the timing of annual peak runoff from snowmelt, summer lowflow stages, the flashiness of runoff events large enough to rework streams 

and alter spawning beds, and change in riffle and pool distributions. 

Reductions in snowpack will alter the hydrograph of rivers in basins 

such as the Columbia, the Sacramento-San Joaquin and, perhaps to a 

lesser degree, the Colorado Rivers. For anadromous fishes, reductions in 

summer low flows may be of greater consequence than earlier peak runoff; 

in portions of western basins, this is already a problem because of water 

withdrawals for irrigation. We make no attempt in this paper to examine 

water resource issues for human uses, but must point to the fact that some 

climate change effects may exacerbate existing stresses from just such 

conflicts.

The flashiness of runoff, and the potential for greater flooding due 

to rain-on-snow events can have mixed consequences: aquatic fauna has 

co-evolved with disturbance. On short time-scales, flood disturbance 

generally brings population decreases for stream reaches. We also know 

that perpetually uniform stream flow does not lead to the highest stream 

productivity. The problem most likely lies with the degree of departure 

from historic extremes, and there may well be thresholds, that when 

exceeded with greater frequencies or exceeded beyond a certain point 

in single events, will have catastrophic impacts on aquatic ecosystem 

productivity. It is not clear if the events depicted in the simulations of 

basin hydrology are well within “normal” ranges or “push the envelope” 

beyond present tolerance limits. The stresses from human development, 

habitat degradation, water withdrawals, and dams are known to have 

pushed many populations toward tolerance limits, and disrupted the 

base on which aquatic productivity rests. Added negative changes from 

whatever source, climate included, could hasten deleterious degradation. 

Biodiversity, Disturbance and Invasives

Observations, thinking, analysis, and modeling all show that 

potential climate change and variability can significantly influence species 

populations, community composition, reproductive success, competitive 

status, and resilience to disturbance patterns. Only fairly recently, it was 

believed that ecosystem processes were too subtle to allow the simple 

determination that observed changes could be attributed to climate 

change. Especially vexing is the added complexity when an ecosystem or 

an entire biome is subjected to the invasion and establishment of a foreign 

The aquatic habitats and the 

fauna adapted to present 

ecosystems will be much 

influenced by the periodicity 

of runoff, such as the timing 

of annual peak runoff from 

snowmelt...

For anadromous fishes, 

reductions in summer low 

flows may be of greater 

consequence than earlier 

peak runoff; in portions 

of western basins, this is 

already a problem because 

of water withdrawals for 

irrigation.
58

(xenobiotic) species; Simberloff (2000) states, “how global climate change 

will affect these impacts has scarcely been addressed.” Fortunately, farreaching implications can be found in the painstaking search of long-term 

records, comparison of old plots, the reexamination of data sets, and the 

modeling efforts now mature enough to convey meaningful results.

The most trenchant summary is the report of the Pew Center 

(Parmesan and Galbraith 2004, but also see Parmesan and Yohe 2003, 

Root et al. 2003). Observations relevant to the American West include 

disruptions to community structure because of earlier spring events 

and the decline of cold-adapted species; the breeding season advance of 

Mexican jays (Aphelocoma ultramarina), which requires parallel advance 

of their food sources to permit continued survival; the earlier emergence 

from denning of marmots (Marmota flaviventris); and a nearly 80 percent 

decline of Edith’s checkerspot butterfly (Euphydryas editha) in their 

southern range (though populations at the northern range limit appear to 

be doing well). On the aquatic side, long-term records in Monterey Bay 

and kelp forest fish communities off southern California show the decline 

of northern species and establishment and dominance of southern species.

The Pew Center report is not alone in delineating the significant 

impact of potential climate change in the faunal community. Thomas et 

al. (2004), writing in Nature, report an analysis of bird extinction risk 

based on an empirical, but well-accepted relationship between the number 

of species and the area occupied by them. The relationship is reported as 

a reasonable predictor of the number of species that become threatened 

or go extinct as the areas available to them is reduced from all possible 

causes, including climate change. Their analysis compares habitat loss 

from reasons other than climate to loss as a result of climate. Using results 

from GCMs with moderate warming scenarios, they conclude that for the 

taxa they examined in their sampling regions, from 15 to 37 percent of 

species will be “committed to extinction,” that to the degree the species/

area relationship applies, extinction is highly likely. The regions examined 

(Mexico, South Africa, Queensland [Australia], Amazonia, and Europe) 

do not include the American West, but can be deemed equally applicable. 

It is important to note that the estimates from Thomas et al. (2004) 

apply to the proportions of species committed to future extinction, not 

the number of species. This observation parallels the work of Sekercioglu 

et al. (2004), whose results are somewhat more ominous, stating that 

by 2100, 6 to 14 percent of bird species will be extinct, and 7 to 25 

percent of bird species will be extinction prone from the sum total of all 

foreseeable causes, including climate change. The significance of birds to 

ecosystem processes such as pollination, insectivory, seed dispersal, and 

decomposition is hard to overstate, as the authors recognize.

Logan et al. (2003) assess the impact of global warming on forest pest 

dynamics and begin with the premise that insects, diseases, and other 

forest pathogens—anthropocentrically called pests—in general have been 

an ever-present threat to “health” when a system is managed or exploited 

for human use. With an affected area that is approximately 45 times 

that of fire (although the per cent mortality may not be comparable) the 

economic impact is 5 times that of fire (Dale et al. 2001, cited by Logan 

Observations relevant to 

the American West include 

disruptions to community 

structure because of earlier 

spring events and the decline 

of cold-adapted species...

The significance of birds to 

ecosystem processes such 

as pollination, insectivory, 

seed dispersal, and 

decomposition is hard 

to overstate...
59

et al. 2003), investigating the potential for exacerbation due to climate is 

not trivial. As with changes in phenology reported above, seasonally earlier 

insect activity compared to prior histories have been observed (Ayres and 

Lombardero 2000). Thus, one would expect changes in herbivory, altered 

predator-prey relations for insects, and regional as well as elevational 

effects (Bale et al. 2002). Logan et al. (2003) posit that the area occupied 

by an invader grows in proportion to the mean dispersal distance per 

reproductive cycle. Such relationships may be tied to climate model 

outputs to assess how insects will respond for future scenarios. 

Multiple Interactions and Feedbacks

There is now considerable evidence that multiple interactions are 

occurring on the land; these will complicate the picture for the future. Fire 

will accompany vegetation shifts and exacerbate the decline where dense 

forests will give way to savannas due to water limitations on productivity. 

Moreover, as we observed, the change in fine fuel abundance will not 

only slow or stop forest reestablishment, but also speed the forest decline 

in those areas. This is exacerbated when the establishment of a grasslike invasive species is added to the mix. Stressed forests become much 

more susceptible to insect attack; the abundant opportunity for insects 

will lead to population surges. The eventual checks from insect predator 

populations may be at risk from unfavorable habitat conditions. The 

analysis of bird extinctions does not inspire confidence that such predators 

will be available. Lastly, we have mentioned that the promise of carbon 

fertilization that might offset some of the negative factors that lead to 

decline in vegetative productivity is not likely to be large and may be 

restricted by highly specific constraints.

The foregoing does not consider that expected dominant vegetation 

that characterizes the particular bird habitat may have changed as well. 

In turn, the analyses of such shifts are usually done without regard to 

human impediments to dispersal, re-establishment barriers, and habitat 

losses. Interdisciplinary work has made great strides in recent times (see 

for example references below that have climatologists, biologists, paleoscientists, hydrologists and modelers in their list of authors). However, 

the science of modeling combined effects of entire suites of processes to 

obtain results that are meaningful, and not merely speculative, is in its 

infancy. 

Implications for Management

At first blush the resource manager is faced with what seems an 

intractable problem. She or he is told that problems of potentially 

serious consequences are posing a threat, but that there is considerable 

uncertainty associated with the problems. Moreover, the consequences are 

reported as an initially disparate set, sometimes at odds with one another. 

Hints are given about their inter-connectedness, yet no self-consistent set 

of recommendations exists by which to approach the management needs.

We regret to say that we cannot provide any simple answers, but we 

do think we can identify some starting points. If everything is thrown at 

There is now considerable 

evidence that multiple 

interactions are occurring 

on the land; these will 

complicate the picture for 

the future. 

At first blush the resource 

manager is faced with 

what seems an intractable 

problem. She or he is told 

that problems of potentially 

serious consequences 

are posing a threat, but 

that there is considerable 

uncertainty associated with 

the problems. 
60

us at once, it will be hard to respond in a logical and decisive manner that 

can yield improvement instead of adding to the chaos. We are told we are 

facing a global rise in temperatures, but one with wide regional differences 

accompanied by precipitation changes that could either increase or 

decrease. A potential increase in climatic variability is forecast, but as yet 

we see no identifiable change in hurricane frequency. We are told that 

these changes will come in concert with other stresses such as human 

encroachment at the urban-wildland interface, increasing pressure on 

conservation areas and perhaps on needed migration routes for both flora 

and fauna, changed timing and extent of run-off and changes in reservoir 

capacity and water demand for human consumption and agricultural 

priorities, and a growing threat from invasive species. Lastly, we are told 

that as yet unknown human responses to these stresses will affect which 

avenues for resource management will be closed or remain open

We can begin to face this challenge by a first-order approach and 

develop secondary options that can be prioritized and brought forward 

for implementation. Five to 10 years ago, the debate took the form of 

a dichotomy of mitigation versus adaptation. Then, mitigation referred 

to action needed to avert climate change, primarily by reductions in 

emissions of greenhouse gases and increases in the sequestration of some 

of them—principally CO2—in the biosphere, and perhaps, the oceans. 

Adaptation strategies were based on the concept that climate change 

effects had a low probability of occurrence, had the potential of even 

being beneficial (who would argue that a warmer, wetter world would not 

be better than a colder, drier one?) and that resulting costs for adaptive 

strategies would be less than costs of mitigation, the latter was believed to 

have an economic slow-down as a by-product. 

The discussion has changed since that time.

As stated earlier, the IPCC concluded that the certainty of warming 

from increasing man-made releases of greenhouse gases has a 90 percent 

probability. Then there is the concept of climate momentum. Increases 

in atmospheric CO2 since the industrial revolution will result in climate 

change even if we are to stabilize emissions to earlier levels. Mitigation 

as initially envisioned is no longer an option—we are seeing the effects 

of climate change, as Parmesan and Galbraith (2004) and others report. 

Mitigation has taken on the new meaning of reducing the negative aspects 

of climate change by prudent action, and has become a part of adaptation. 

We hasten to add that this does not imply that action to reduce emissions 

or enhance sequestration would be useless. Even prolonging the time 

it takes CO2 emissions to double may have significant benefits, but we 

want to alert the reader to a change in the operating framework we find 

ourselves.

We begin with recommendation at the local scale, and end with 

implications for managers at the broadest scale.

Recommendations of authors cited above reflect the perspective 

developed in their area of expertise after thorough study of climate change 

effects in their field. We cite those relevant to managers:

...the IPCC concluded that 

the certainty of warming 

from increasing man-made 

releases of greenhouse gases 

has a 90 percent probability. 

Mitigation has taken on the 

new meaning of reducing 

the negative aspects of 

climate change by prudent 

action...
61

When considering vegetation change responses, Bachelet et al. (2003) 

suggest: 

... managers would be well advised to develop contingency plans 

for alternative futures, increased vegetation growth, or increased 

vegetation stress, with specific regional patterns and timing to 

both. Monitoring could be configured to identify these alternative 

conditions as they occur. 

Fagre et al. (2003) stress:

It is critical that we understand the effects of climatic variability 

on mountains, because mountains support a high diversity of 

ecosystems and provide a wide range of ecological services to 

human populations. Mountains serve as the world’s water towers by 

providing 50 percent of freshwater consumed by humans.

For range management Shafer et al. (2001) observe: 

... range fragmentation may be a significant problem for some 

species. [In the West] areas of future bioclimatic habitat... are often 

small and disjunct, reflecting the heterogeneity of the landscape. 

Land-use activities will both severely restrict the amount of suitable 

habitat available... and impede [the species’] ability to successfully 

disperse...

Regarding fire and vegetation responses in California, Lenihan et al. 

(2003) state: 

... results will indicate fire will play a critical role in the adjustment 

of vegetation to any of the later precipitation regimes for California, 

be it slowing the encroachment of woody vegetation in grasslands or 

hastening the transition from woody communities to grassland under 

drier conditions.

Sticking to the practical on the same subject, Flannigan et al. (2000) 

recommend: 

Possible manipulations of fuel type, load and arrangement could 

be used to help protect local areas of high value. A fine balancing 

act is required by managers to protect values (people and resources) 

from fire, while... allowing fire to resume... its role in ecosystem 

functioning and maintenance. Manage ignitions sources: create and 

adopt local ordinances to reduce human-caused ignitions.

By contrast, Brown et al. (2004) make sweeping recommendations on 

a broad scale, given with a pessimistic flavor—we will return to them at 

the end of this section:

Policy makers face formidable challenges in ecosystem management 

and stewardship given socioeconomic desires and the physical 

outcomes from both climate change and human decisions. Our 

results suggest new fire management strategies and policies may be 

needed to address the added climatic risks.

...managers would be 

well advised to develop 

contingency plans for 

alternative futures

A fine balancing act is 

required by managers...
62

For dealing with the considerable problem of invasive species, large 

enough without the confounding factor of climate change and variability 

and interaction with fire regimes, Brooks et al. (2004) stick to the 

practical, proceeding from the tried and true to the more thorny areas by 

summarizing thus (paraphrased): 

If invaders promote fire: manage fuels: eradicate or reduce 

dominance; establish fire-resistant vegetation that competes; create 

firebreaks; manipulate to restore pre-invasion vegetation and fire 

regimes; limit land-use conditions that increase invader dominance.

If invaders reduce fire: manage fuels: eradicate or reduce 

dominance; restore pre-invasion fuel structure; mechanically or 

chemically treat to increase flammability; restore pre-invasion 

fire regime; limit contrary land-use. Manage ignitions sources: 

use prescribed fire after fuel bed alteration for flammability; use 

prescribed fire often when possible.

The manager needs no primer to tell him or her the costs of 

undertaking such steps.

What are the manager’s responsibilities in the broader arena, where 

policies must be developed or advocated, which may clash with political 

realities? What is or should be the role of the manager in situations 

where current knowledge is inadequate to allow future directions to be 

identified, and recommendations for new research direction may have to 

be stressed?

These are question we cannot answer as members of the research 

community. We would respectfully suggest, however, that managers, as do 

scientists and others possessing special expertise, bring their understanding 

of the implications of current practices to top level administrators, policy 

groups, and the general public. This is not done in an advocacy role, but 

in the neutral, objective role reflected in the “if, then...” approach. If you 

continue a particular policy, then it is our job to tell you the consequences 

you will find yourself faced with. These may be undesirable, or desirable, 

but may have side effects that cannot be minimized beyond a certain 

point; policy makers or policy advocates must take all of them into 

account when mapping the future.

If resource managers are faced with uncertain, but highly likely 

knowledge that effects such as the probable extinction of bird species 

that provide ecosystem services such as pollination, predator control, and 

decomposition is already occurring or becomes a near-term risk, then they 

must call attention to the fact that their assigned responsibility cannot be 

met given their existing resources and policy direction.

Hence the observation by Brown et al. that “... managers face 

formidable challenges...” and further emphasized by Thomas et al. 

(2004): 

... anthropogenic climate warming at least ranks alongside other 

recognized threats to global biodiversity... many of the most severe 

impacts of climate are likely to stem from interactions between 

We would respectfully 

suggest, however, that 

managers, as do scientists 

and others possessing 

special expertise, bring 

their understanding of the 

implications of current 

practices to top level 

administrators, policy 

groups, and the general 

public. 
63

threats in many if not most regions. Returning to near pre-industrial 

global temperatures as quickly as possible could prevent much of the 

projected, but slower acting, climate related extinction from being 

realized.

The most comprehensive approach is that of Parmesan and Galbraith 

(2004), who restate “the big picture” interpretation of where we find 

ourselves today, and where this must take us. They give particular 

recognition to the problem of interaction among many stressors acting on 

natural resources:

“There is growing consensus within the scientific community that climate 

change will compound existing threats and lead to an acceleration of 

the rate at which biodiversity is lost (emphasis added). Reducing 

the adverse effects of climate change on U.S. ecosystems can be 

facilitated through a broad range of strategies, including adaptive 

management, promotion of transitional habitat in non-preserved 

areas and the alleviation of non-climate stressors. [This includes] 

... promoting dynamic designs and management plans for nature 

reserves [which] may enable managers to facilitate adjustment of wild 

species to changing climate conditions.

They continue with a call that is both a plea for managers to continue 

to develop their expertise and for some research initiatives by stating: 

A major future challenge is to achieve a better understanding of 

which systems or species are most or least susceptible to projected 

climate change. [We need the] ... development of ... vulnerability 

assessment tools and methods ... begun only recently, [and need to] 

reassess species and habitat classification to evaluate their relative 

vulnerabilities to GCC [as well as] design new reserves to allow 

for shift in distribution of target species, promote native habitat 

corridors between reserves, practice dynamic rather than static 

habitat conservation planning [and] alleviate effects of other stressors.

Conclusion

Observational evidence that climate is warming is increasingly 

obvious. The link of climate change to man-made inputs of greenhouse 

gases to the atmosphere is only slightly less clear. More importantly, 

responses to the climate change are manifest in both the physical and 

in the biological realm. The breakup of large parts of the Antarctic ice 

shelf, the receding of glaciers worldwide, the reduction in polar sea ice, 

the loss of arctic permafrost, and warming trends in high latitudes are 

strong indications of the former, while the earlier onset of green-up, 

the displacement or loss of high-latitude species in many regions both 

terrestrial and coastal, and the infilling of alpine tundra by sub-alpine 

forest are but a few examples of the latter.

Resource managers are only too aware that multiple stresses affect the 

systems they are charged to protect or from which they are expected to 

permit a sustainable flow of ecosystem services; to these stresses climate 

change is now added. In some cases, climate responses will exacerbate the 

“There is growing consensus 

within the scientific 

community that climate 

change will compound 

existing threats and lead to 

an acceleration of the rate at 

which biodiversity is lost...”

A major future challenge 

is to achieve a better 

understanding of which 

systems or species are most 

or least susceptible to 

projected climate change.
64

existing stresses—fire frequencies and intensities may hasten ecosystem 

degradation from other causes; vegetation shifts can be accelerated or 

slowed by fire. Invasive species affect fire regimes and induce positive or 

negative feedbacks. Insects and pathogens, and their natural predators 

will change in numbers, population dynamics and areal extent. Some 

indications of how such processes play out has been suggested. However, 

comprehensive modeling of all of the above into forecasting a single 

outcome is in its infancy, and needs to be nurtured.

One emerging outcome is that the resources to be managed are not 

static systems, and that their dynamism is accelerated by climate change. 

This has profound implications for management. It changes how we 

approach conservation reserves, view development at the wildland-urban 

interface, think about habitat, and envision future migration corridors. It 

opens up the need for new thinking over that of the day-to-day priorities 

of a resource manager. Seed dispersal, the role of pollinators, influence of 

topographic, man-made constraints to migration, and potential conflicts 

between community, agricultural and aquatic-system water needs will 

require new thinking and demand responses at multiple organizational 

levels.

Knowing how to develop a “no-regrets” strategy, how to think 

about present and future costs of protecting ecosystem services, how to 

integrate such costs into economic analysis is needed. Classical analysis 

has historically viewed the environment as an inexhaustible reservoir. 

This is no longer tenable. On the issue of mitigating climate change 

versus adapting to its consequences, the manager may well want to think 

through the implications and costs of either strategy and voice his or her 

expert knowledge of which road to travel.

Acknowledgments

The scientific, technical and editorial help of Linda Joyce, the expert 

editing assistance of Zoe Hoyle, the generous contributions of the figures 

by Dominique Bachelet and Jim Lenihan, as well as the library research by 

Michele Laskowski and others is hereby gratefully acknowledged.

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67

Social and Economic Issues of Global Climate 

Change in the Western United States

Randall S. Rosenberger 1

1Environmental economist, Department of Forest Resources, College of Forestry, Oregon State University, Corvallis, OR 97331.

Tom Iraci, USDA Forest Service

Erik Ackerson, EarthDesign, Ink

Mark Reid, USDA Forest Service

Erik Ackerson, EarthDesign, Ink
68

Abstract

Global climate change and its attendant environmental changes will 

affect the functioning of our social and economic systems. This paper 

provides an overview of social and economic issues pertaining to global 

climate change impacts in the Western United States. A values typology 

that links human values with ecological functioning is introduced. This 

typology provides a motivation for developing strategies to minimize 

the impacts of climate change through mitigation and adaptation. Four 

research themes are introduced, including policy-relevant science, microscale analyses, non-market valuation, and local adaptation.

Keywords: Climate change, social, economic, mitigation, adaptation.

Introduction

The Intergovernmental Panel on Climate Change (IPCC) projects 

mean global temperatures will increase by 2.5-10.4oF (1.4-5.8oC) 

this century, with continued increases in mean temperature thereafter 

(Houghton et al. 2001). In the United States, mean temperatures are 

expected to increase by about one-third greater than the global mean; i.e., 

4-14oF (2-80C) (Wigley 1999). In the United States, mean temperatures 

have already increased by 1oF (0.6oC) and precipitation has increased 

by 5-10 percent over the past century (Parmesan and Galbraith 2004). 

Generally there is scientific consensus that humans are contributing 

to climate change through increased atmospheric concentrations of 

greenhouse gases and land use changes (Oreskes 2004). The question 

is not whether climate is changing, but by how much, when, and what 

impacts it is likely to have on ecological, social and economic systems. 

The IPCC (2001) and Smith (2004) identify several likely 

consequences of climate change on ecological, social and economic 

systems:

• Agriculture–changes in growing season; available soil moisture and 

nutrient balances; depleted water supplies;

• Water–variability in precipitation patterns resulting in droughts, 

floods and water shortages in certain areas, especially the arid 

southwest; reduced snowfall;

• Coastal communities–sea level rise from melting glaciers and ocean 

warming;

• Human health–more frequent and severe heat waves and increased 

air pollution; migration northward of tropical diseases;

• Terrestrial ecosystems–migration of colder regions northward and 

in elevation; reduced snowfall; changes in stream ecology through 

variable runoff and warmer water temperatures;

• Forestry–changes in growing conditions; increases in extreme 

events such as droughts, pest outbreaks, and wildfire frequency and 

intensity; expansion of timber production to agricultural lands;

The question is not whether 

climate is changing, but by 

how much, when, and what 

impacts it is likely to have 

on ecological, social and 

economic systems. 
69

• Biodiversity–changes in species composition from habitat losses, 

reduced in-stream flows, warmer water temperatures, and loss of 

wetlands; most at risk include coldwater species of fish, endangered 

species, and migratory waterfowl;

• Energy–increased energy demands for summer cooling, especially in 

the southwest but also expanding into regions with historically cool 

summer temperatures; and

• Recreation–changes in fishing opportunities; lengthening of summer 

season activities; reduction in skiing opportunities.

In a Pew Center report, Smith (2004: 19) summarized the likely 

impacts of temperature changes on different sectors in the United States 

based on evidence from the scientific literature. With a few degrees of 

warming (up to 7oF [4oC]) over the next century, national impacts are 

expected to be:

• Agriculture–a medium confidence in net benefits,

• Water–uncertain direction of impact,

• Coastal communities–high confidence in net damages,

• Human health–a medium confidence in some net benefits, some net 

damages,

• Terrestrial ecosystem productivity–a low to medium confidence in 

net benefits,

• Terrestrial biodiversity–a medium confidence in net damages,

• Forestry–a low to medium confidence in net benefits, and

• Aquatic biodiversity–a low confidence in net damages.

These likely impacts of climate change are a function of our 

expectations regarding the degree of warming, their effects on human and 

ecological systems, and the ability of these systems to respond to climate 

change signals. Economic and social systems (such as agriculture, forestry, 

and coastal developments) in the United States are less vulnerable (i.e., 

resilient) to climate changes than are natural ecosystems (Smith 2004). 

E.g., agriculture and forestry may benefit from lengthened growing 

seasons and increased carbon dioxide concentrations. The most recent 

analyses of climate change impacts on social and economic systems show 

that the U.S. economy is not greatly threatened by climate change over 

the 21st century (Mendelsohn 2001). In fact, these studies suggest national 

net benefits could range up to one percent of GDP. Smith (2004: iv) 

summarizes that while several sectors within the United States are sensitive 

to climate change, they are not vulnerable due to a significant capacity to 

adapt:

The country’s high per capita income, relatively low population 

density, stable institutions, research base, and health care system give 

the United States a strong capacity to adapt to climate change. ... The 

country’s large size and the population’s mobility give it advantages in 

adapting to climate change. The lower 48 states span more than 20 

degrees of latitude in the temperate zone, so while some southern parts 

of the country are at relatively higher risk from climate change, more 

northern areas are at less risk or may have many benefits.

The country’s high per 

capita income, relatively low 

population density, stable 

institutions, research base, 

and health care system give 

the United States a strong 

capacity to adapt to climate 

change.
70

With greater than 7oF (4oC) of warming over the next century, 

national impacts are expected to be negative (net damages) with the 

exception of uncertainty regarding impacts on human health (Smith 

2004). The expected impacts of climate change are prefaced on a gradual 

warming along with changes in regional precipitation patterns. If climate 

changes suddenly and catastrophically, all bets are off. The magnitude 

of likely impacts due to increasing temperatures varies across different 

regions of the United States.

Climate Change Impacts in the West

The Western United States is quite diverse not only in its topography 

and climate, but also in its distribution of people on the landscape. The 

West contains many states that have been the fastest growing in the nation 

over the last two centuries, compounding other issues such as resource 

allocation and land-use changes. While most of the population in the 

West resides in urban areas, communities are dispersed across the region 

with varying degrees of dependence on availability and access to natural 

resources. In addition, most rural areas in the West are dominated by 

public landownership (Travis 2003). Rural areas may be most at risk from 

changes in climate due to their relatively higher degrees of vulnerability 

to climate change (increased exposure, sensitivity, and lack of adaptive 

capacity). Miller and Gloss (2003: 251) note that the “west shows great 

heterogeneity in (1) the problems caused by climate variability, (2) current 

flexibility, (3) institutional constraints, (4) interests and perceptions of 

participants, (5) resources available to them, and (6) policy options.” 

Therefore, the impacts of climate change cannot be evaluated out of 

context of existing stresses on natural, social and economic systems, 

including aridity, water shortage, burgeoning populations, and land use 

changes (Wagner 2003).

Climate change is a global phenomenon that will have some effect 

on all scales nested within the global framework. We can generally expect 

climate change to effect local economies, public health, water supplies, 

electric power production, and key industries such as tourism, agriculture 

and forestry in the long-term. In addition, we can expect an increase 

in the frequency and severity of weather events, and coastal areas could 

see an increased risk from sea level rise and storm surges. We can expect 

southern regions to be more vulnerable to climate change than northern 

regions (IPCC 2001, Shugart et al. 2003, Smith 2004). 

A synthesis of evidence for the southwest (Smith 2004: 23) concludes:

The Southwest has quite different vulnerabilities to climate change 

than the rest of the country. It is the most vulnerable region in terms 

of water supplies (Hurd et al. 1999) because of the combination 

of a semi-arid to arid climate and relatively high withdrawals 

of water resources. Earlier snowmelt could increase the risk of 

winter flooding and summer shortage of water supplies, thereby 

exacerbating current water scarcities. Should there be increased 

average annual runoff, some supply concerns may be alleviated, but 

flooding should increase. Agriculture in the region is projected by 

The expected impacts of 

climate change are prefaced 

on a gradual warming along 

with changes in regional 

precipitation patterns. If 

climate changes suddenly 

and catastrophically, all 

bets are off. 

We can generally expect 

climate change to effect local 

economies, public health, 

water supplies, electric 

power production, and key 

industries such as tourism, 

agriculture and forestry in 

the long-term.
71

economic models to fare relatively well. However, with about 90 

percent of the region’s water consumption going to agriculture, a 

reduction in water supplies could have a substantial negative effect 

on that sector. Biodiversity in the region is likely to be reduced 

because of the complex topography and human development (e.g., 

dams blocking migration of fish). Yet mountains such as the Rocky 

Mountains and Sierras also provide north-south and altitudinal 

migration corridors for some species. Interestingly, species in the 

Southwest (and Northwest) may not always migrate toward the 

north because of complex terrain and substantial variances in climate 

across these regions. Vegetation biomass could increase or decrease, 

depending on whether the Southwest becomes wetter or drier. 

There is generally less risk to coastal areas in California than in the 

Northeast, Southeast, or Southern Great Plains. Nonetheless, San 

Francisco Bay, the Sacramento-San Joaquin Delta, and many parts 

of southern California are at risk from sea-level rise. Risks to human 

health are relatively low because heat stress is not a significant risk in 

urban areas and there is limited risk of infectious disease outbreaks 

(although infectious diseases such as hantavirus are a problem in the 

region). The region’s ski industry is likely to be harmed, although 

warm weather recreation activities could expand. 

A synthesis of evidence for the Northwest (Smith 2004: 24) 

concludes:

It can be argued that the Northwest’s relatively cool climate and 

wet conditions (at least in the western portions of Oregon and 

Washington) make the region less vulnerable to climate change 

than warmer or drier regions, yet the region has some distinct 

vulnerabilities. Changes in the seasonality of runoff could be 

problematic for management of the region’s water resources 

infrastructure (Hamlet and Lettenmaier 1999). Much of the coast 

is not vulnerable to sea-level rise, with the notable exception of 

the highly developed Puget Sound area. Agricultural production 

is estimated to increase in the region (Adams et al. 1999), and 

ranching could benefit if grassland productivity increases. The 

effects of climate on forests in the region are uncertain. Under some 

scenarios, productivity increases, while under others it decreases. 

Higher temperatures may benefit forests in the region only up to a 

point, and then they may become a detriment (Neilson and Drapek 

1998). As in the other regions, biodiversity is expected to be harmed, 

although vegetation productivity could increase. The valuable 

salmon fishery may be at particular risk from rising temperatures and 

changes in runoff patterns. 

The biggest winners from climate change are probably agriculture and 

summer recreation (high capacities to adapt), while the biggest losers are 

likely to be water resources and energy sectors (long-lived infrastructure 

with limited adaptive capacity) (Mendelsohn and Neumann 1999, Smith 

2004). A shift of land from agricultural production to timber production 

is expected to be mainly an issue for the West (Sohngen and Mendelsohn 

1999). However, the overall impact climate change will have on individual 

The biggest winners from 

climate change are probably 

agriculture and summer 

recreation (high capacities 

to adapt), while the biggest 

losers are likely to be water 

resources and energy sectors 

(long-lived infrastructure 

with limited adaptive 

capacity)...
72

economic sectors, social systems, communities, and individuals depends 

on how well and when we decide to mitigate the causes of climate change, 

and to reduce or adapt to changes in ecological systems brought on by a 

changing climate. 

Scientific Consensus and Social Values: 

A Prescription for Action

Given the level of scientific consensus and concern about climate 

change, why is the world barely beginning to take action? Part of the 

problem seems to lie in the void between scientific opinion and lay 

opinion (Robert Socolow as quoted in Kolbert 2005). Social, political and 

economic responses to climate change will require a shift in preferences for 

public and private managers, politicians, and consumers. These necessary 

shifts in preferences will take place when managers, politicians, and 

consumers accept the signals that climate is changing, that we need to do 

something about it, and we are willing to incur the (possibly substantial) 

costs of avoidance. Unfortunately, the lay public does not seem to see 

the signals or heed the warnings; scientific consensus is tenuously held 

by citizens and not supported by citizen’s perceptions of climate patterns 

in the short term (e.g., marginal changes in climate patterns from year 

to year are not easily perceived by people). It may take a catastrophic, 

climate-related episode to finally get people’s attentions to the likely future 

state of the world. A case in point is the recent tsunami in the Indian 

Ocean that affected Southeast Asia. It took this type of catastrophic event 

before politicians, managers and citizens would pay significant attention 

to warnings by scientific experts about tsunami preparedness in the Pacific 

Northwest.

Ecological and Socio-Economic Linkages

What is sustainability? In the context of their sustainable forest 

management initiative, the USDA FS (2005) defines sustainability as “the 

human desire for an environment that can provide for our needs now 

and for future generations.” Sustainability is a human value that requires 

human judgment regarding the current and desired future condition of 

the world. Scientists, managers, politicians and citizens recognize the 

interconnectedness, complexity and dynamism of social, economic and 

ecological systems (USDA FS 2005). This recognition is based on decades 

of scientific and political debate, the evolution of people’s preferences, 

and the development of our economic and social systems. The desire to 

improve human well-being is broadly recognized to be based on economic 

prosperity, social equity and environmental quality. However, the 

multitude of often competing human values and different desired future 

conditions not only necessitates continuing the debate about sustainable 

management, but expanding it to include all concerned parties (scientists, 

managers, politicians and citizens) in public discourse (USDA FS 2005). 

Climate change must be part of this discourse.

Humans, including their economic and social systems, are supported 

by ecological systems. Ecological systems affect and are affected by a wider 

network of systems, including social and economic ones. Sustainable 

Unfortunately, the lay public 

does not seem to see the 

signals or heed the warnings; 

scientific consensus is 

tenuously held by citizens 

and not supported by 

citizen’s perceptions of 

climate patterns in the 

short term...

Ecological systems affect 

and are affected by a 

wider network of systems, 

including social and 

economic ones. 
73

management integrates these systems in an attempt to promote their 

sustainability across space and over time (fig. 1). Climate change and 

climate variability affect these systems directly and indirectly, as noted 

above. De Groot et al. (2002) identify four functions of ecosystems and 

the goods and services derived from them:

• Regulation functions–The maintenance of essential ecological 

processes and life support systems, including gas regulation, climate 

regulation, disturbance prevention, water regulation, water supply, 

soil retention, soil formation, nutrient regulation, waste treatment, 

pollination, and biological control;

• Habitat functions–The provision of habitat for wild plant and 

animal species, including refugium (adequate living space) and 

nursery (adequate reproduction habitat) services;

• Production function–The provision of natural resources, including 

food, raw materials, genetic resources, medicinal resources, and 

ornamental resources; and

• Information functions–The provision of opportunities for cognitive 

development, including aesthetic information, recreation, cultural 

and artistic information, spiritual and historic information, and 

science and education.

Through policy and regulations, management, and voluntary actions 

we may be able to curtail or at least slow down trends in human-caused 

climate change, or adapt to changes in ecosystem functioning that directly 

or indirectly affect social and economic systems. A better understanding of 

the link between those things we value and climate change seems a logical 

step in raising public awareness of the likely consequences if we continue 

to ignore the signals. 

Economic value is generally defined as the amount of one good or 

service that must be given up to obtain an increase in another good or 

service. Therefore, economic values are relative in the sense that they are 

measured in terms of something else (opportunity cost). To measure these 

relative values, we must define the source of people’s values for goods 

and services supported or provided by ecosystems. The following section 

on economic values is not to be confused with ‘total valuation.’ Total 

valuation would include the value of ecological functions themselves, of 

which people may not always be aware (NRC 2005). In addition, ‘total 

economic value’ as the aggregation of individual values may not be the 

same as the social value of an ecosystem. Social value would include 

broader considerations of the value of ecosystem functions beyond the 

values individuals gain from them. E.g., equity or fairness in the sharing 

of harms and benefits may be a social value that transcends individual 

values and interests. It is likely that the total value of ecosystems is more 

than the sum of their individual parts.

To measure value in economic terms, a link between ecological 

functioning and economic valuation must exist. Figure 2 labels this link 

as the ecological-economic interaction. Economic values of ecosystems 

depend on the functioning of these ecosystems. However, these functions 

are not necessarily directly valued by people. Economic values are derived 

Through policy and 

regulations, management, 

and voluntary actions we 

may be able to curtail or 

at least slow down trends 

in human-caused climate 

change...
74

from the goods and services supported by these functions. E.g., certain 

biotic characteristics are necessary to support viable fish populations, but 

it is fishing quality that is valued by the angler.

Why Should We Care About Climate Change? 

A Values Typology

The natural environment is important to people in a variety of ways. 

People value natural environments as part of what constitutes their 

quality of life. People’s dispositions toward their natural environments 

motivate their behavior and decisions as they allocate scarce resources in 

pursuit of happiness or well-being. The quantity and quality of natural 

environments, along with climate and management-induced changes in 

natural environments, also affect individuals’ abilities to produce value. 

An environmental good or service has economic value if it increases 

human well-being. At the root of economic value is the individual human 

and it is based on this individual’s preferences for one thing over another 

that constitutes economic value; i.e., we do not prefer a good or service 

because it is valuable, it is valuable because we prefer it. The economic 

value of a good or service is derived when an individual uses a resource to 

produce satisfaction (or value or benefit), where this use is an allocation 

of scarce resources (time and money) in the production of preferred 

outcomes, experiences, or knowledge. The appropriate context for 

economic valuation is estimation of the relative value of a good in relation 

to what a person is willing to give up (‘willing to pay’) or willing to accept 

compensation for a good or service. 

Figure 1—Integration of ecological, economic and social systems within an adaptive, sustainable 

management framework.

Infrastructure

Open space

Institutions Recreation

Plant and animal health,

environmental quality

HUMAN

WELL-BEING

Society and

economy

Production

Social justice

Ecological

habitat

Human

habitat

People’s dispositions toward 

their natural environments 

motivate their behavior and 

decisions as they allocate 

scarce resources in pursuit 

of happiness or well-being.
75

An efficient outcome occurs when the benefits of an action (e.g., 

allocation of resources) outweigh the costs of that action. In a democratic 

society, values permeate resource allocation decisions related to land 

and resource management. An administrator’s or manager’s decisions 

should reflect the values held by their constituents, including the 

general public, in the formulation, selection and implementation of 

management alternatives (Lewis 1995). Therefore, understanding how the 

general public values natural systems and future conditions is critical to 

identifying efficient and effective responses to climate change. Thus, we 

complete the circle and return to the issue of public discourse regarding 

sustainable management and climate change.

Pete Morton (1999) merged an economic value classification 

schematic with an environmental philosopher’s schematic of humanderived values from natural areas (Rolston 1985). Figure 3 reproduces 

Morton’s value classification schematic.

• People may derive direct use benefits from natural areas, both 

managed and protected. Direct use benefits may include on-site 

recreation; mental, physical and/or spiritual regeneration; cultural 

heritage (both as natural history such as unique rock formations, 

cultural history such as archeological sites, or natural/cultural 

heritage and symbolization such as forestry’s role in the history of 

the Pacific Northwest or the beaver as Oregon’s state animal); and 

commercial uses (such as agriculture, timber harvesting, mineral 

extraction, and collection of non-timber resources). 

Human-controlled

inputs

Attributes of

ecosystems

Structure Process

INPUTS

Ecosystem

goods and services

Individual utility Individual

preferences

Direct

use values

Indirect

use values

Passive-use

values

Individual

valuations

Prices, constraints,

Individual use

levels

ECOLOGICAL

FUNCTIONING

ECOLOGICALECONOMIC

INTERACTIONS

ECONOMIC

VALUATION

Ecosystem

inputs

Figure 2—Schematic of valuing ecosystems (adapted from Randall 1984 and Turner et al. 2000).

...understanding how 

the general public values 

natural systems and future 

conditions is critical to 

identifying efficient and 

effective responses to 

climate change.
76

• People may derive community benefits from natural systems as they 

support jobs, whether these jobs are recreation and tourism-based or 

resource extraction-based, and other contributions to the quality of a 

place to live and/or do business.

• People may derive benefits from the scientific values of natural 

systems in the form of research areas, educational tools, and 

evaluation of management outcomes (an important component to 

adaptive management). 

• Natural areas may provide off-site benefits to people in the form 

of off-site hunting and fishing, off-site recreation, scenic viewsheds, 

enhanced property values, and other non-consumptive uses (photos, 

books, stories about areas, history, etc.). 

• Natural areas may provide biodiversity conservation benefits

that include preserving genetic diversity. Biodiversity conservation 

also sustains passive use values by providing sanctuaries for rare or 

endangered species. 

• Protected natural areas and managed natural areas may provide 

benefits through sustaining ecological services such as the 

protection of watersheds, nutrient recycling, natural pest control, 

and carbon storage. 

• People may derive option value benefits from natural areas for 

future active use of the areas both on-site and off-site. 

• People may derive bequest value benefits by knowing that certain 

areas and all they contain will be there for future generations’ 

benefits. 

• And people may derive existence value benefits from knowing that 

protected natural areas will exist into the future, independent of any 

human active use of the resources.

Loomis and Richardson (2000) estimated recreation benefits, passive 

use benefits and jobs supported by the 42 million acres of roadless 

natural areas in the coterminous 48-states. They estimated recreation 

benefits supported by these areas at almost $600 million annually and 

the passive use benefits of these areas at about $280 million annually. 

Figure 3—Morton’s value classification schematic for wilderness areas (adapted from Morton 1999).

Total

economic beneftis

Direct use

benefits

Community

benefits

Scientific

benefits

Off-site

benefits

Biodiversity

conservation

Passive use

benefits

Ecological

services

Option

value

Bequest

value

Existence

value
77

They also estimated these roadless areas support almost 24,000 jobs in 

the continental United States. In the Western United States, these values 

were estimated to be $535 million, $274 million, and 21,000 jobs for 

recreation benefits, passive use benefits, and supported employment, 

respectively. Carbon sequestration benefits derived from roadless areas 

were estimated to range from nearly $500 million to $1 billion annually.

Krieger (2001: iii) reviewed economic values for forest ecosystem 

services in the United States. He notes:

Globally, Costanza et al. (1997) estimated the total value of forest 

ecosystem goods and services at $4.7 trillion annually and the total 

annual value of all temperate/boreal forests at $894 billion. There 

are about 520 million acres of temperate/boreal forest in the United 

States (Pimentel et al. 1997), with an implied annual value for 

services of about $63.6 billion, using Costanza’s estimates. Climate 

regulation, waste treatment and food production account for 

approximately 75 percent of this total.

Table 1 summarizes evidence provided in this report and elsewhere 

under the structure of the values matrix provided in figure 3. Based on 

this matrix we can identify where we have information along with where 

data are lacking. In general, we have more information and are relatively 

more certain regarding the impacts of climate change on commercial 

activities (agriculture, timber, water, energy, and coastal property) than 

impacts on other value types. How people are likely to respond to climate 

change is less certain, especially about changes in recreation resources, 

community benefits, scientific benefits, biodiversity conservation, 

ecological services, and passive use values. The spatial scale of analyses 

further exacerbates the problem of modeling climate change impacts in 

an uncertain future as we move from global scale models to local scale 

models.

The consequences of climate change are not to be taken lightly. While 

the impacts of climate change are expected to be greater for unmanaged 

natural environments (wilderness and other protected reserves) than 

for either social, economic or managed natural systems (agriculture, 

timber, water resources) in the United States (Smith 2004), the degree 

of impact and difficulty in measuring impacts of climate change are 

compounded by social and economic trends such as land-use changes, 

population growth, and changes in income distribution, human values 

and consumer preferences (IPCC 2001, Joyce et al. 2000). Social and 

economic uncertainties associated with population growth and migration, 

consumption rates, technology, policies and preferences dominate 

uncertainties regarding biophysical and ecological changes due to climate 

change (NRC 1999). Therefore, our ability to precisely predict impacts 

of climate change on social and economic systems depends on our ability 

to predict how people will respond to a changing climate, where we have 

our greatest uncertainty. Nonetheless, we do know that a changing climate 

will affect ecological, social and economic systems, which in turn will 

ultimately affect human well-being as we know it. 

How people are likely to 

respond to climate change 

is less certain, especially 

about changes in recreation 

resources, community 

benefits, scientific benefits, 

biodiversity conservation, 

ecological services, and 

passive use values. 

...our ability to precisely 

predict impacts of climate 

change on social and 

economic systems depends 

on our ability to predict 

how people will respond to a 

changing climate...
78

Value Type Sector Impactsa

Direct use Benefits Agriculture

Southwest medium confidence in some net benefits, some net 

costs; Northwest medium confidence in net benefits (Smith 

2004)

Forestry Uncertain direction of change (Smith 2004)

Recreation Medium confidence of net benefits across all regions (Mendelsohn 

and Markowski 1999; Loomis and Crespi 1999).High confidence 

of net damages to snow-related activities (Wagner 2003; Mendelsohn and Markowski 1999; Loomis and Crespi 1999)

Water Southwest low confidence in net damages; Northwest low confidence in some net benefits, some net damages (Smith 2004)

Health Medium confidence in some net benefits, some net damages 

(Smith 2004)

Energy Low confidence in energy savings in Northwest and energy costs 

in the Southwest (Mendelsohn 2001)

Community Benefits Resource-dependent and nature-based tourism-dependent communities at greater risk of climate change (Wagner 2003). Diversified communities at less risk of climate change (Wagner 2003)

Scientific Benefits Climate change effects will be ubiquitous, providing many natural 

labs for evaluating the effect of climate change on natural, social 

and economic systems. However, places representing pre-climate change conditions may not exist. (No studies known)

Off-Site Benefits Coastal 

Communities

High confidence in small net damages to coastal properties (Smith 

2004; Mendelsohn 2001)

Property

Values

Changes in natural amenities, migration of natural areas, economic sectors (skiing, forestry, agriculture), and changing landscapes and viewsheds could lead to increases or decreases in 

property values (Wagner 2003)

Biodiversity Conservation Medium confidence in net damages to terrestrial biodiversity, in 

particular loss of alpine areas (Smith 2004). Low to medium 

confidence in net damages to freshwater aquatic biodiversity, 

in particular displacement of coldwater species with warmwater 

species (Smith 2004). Protected natural areas are particularly at 

risk of climate change (Hardy 2003)

Ecological Services Low confidence in some net benefits, some net damages (Smith 

2004)

Passive Use Values Little evidence. Values transcend space and time. Extinction of 

ecosystems (alpine areas), species (salmon and other currently 

endangered species), or industries (salmon fishery, snow skiing) 

may trigger passive use value responses from people (Hardy 

2003; Smith2004)

Table 1—Summary of likely impacts from climate change by value type for the Western United States.

aMost references cited regarding impacts are syntheses of past research.
79

What Can We Do About Climate Change?

Many sectors in the U.S. economy are sensitive to climate changes 

(Smith 2004), but they are not necessarily vulnerable to these changes. 

Vulnerability to climate change is a function of three factors—the 

degree of exposure to climate; sensitivity to effects of climate change 

on ecological, social and economic systems; and adaptive capacity

(the ability to adapt to a changing climate) (McCarthy et al. 2001). 

Adaptive capacity depends on a community’s wealth, access to technology, 

effective and stable institutions, efficient mechanisms for disseminating 

information, an equitable distribution of power, and a well-functioning 

social system (Smith et al. 2003). While many sectors in the U.S. 

economy are resilient and have a high capacity to adapt resulting in low 

impacts from climate change, sectors with long-lived infrastructure (water 

and coastal resources) are not able to adapt quickly to a changing climate 

(Smith 2004). 

There are three general categories of responses to climate change—

indirect policy options, mitigation options and adaptation options (Jepma 

et al. 1996). Indirect policy options target those social and economic 

trends that contribute to the climate change problem—population 

growth, resource demands and supply, and technology. While indirect 

policy options do not directly target factors associated with climate 

change, they can have a substantial impact on the concentration of 

greenhouse gases in the atmosphere by indirectly affecting greenhouse gas 

emissions or greenhouse gas uptake in sinks (Jepma et al. 1996). 

Mitigation Strategies

Mitigation strategies target greenhouse gases that contribute to global 

warming by reducing the amount of gases being emitted by our economic 

system or through lowering the atmospheric concentrations of gases by 

sequestering them in forests, soils and oceans (IPCC 2001, Klein and 

Smith 2003, Smit et al. 2000). The IPCC’s Third Assessment Report 

identified various levels of mitigation potential and provided some barriers 

to realizing these potential levels (IPCC 2001):

• Market potential–This is the level of potential that we have actually 

achieved and is a function of the amount of environmentally sound 

technologies and practices we actually use today.

• Economic potential–This is the level we can approach through the 

creation of markets, the reduction of market failures, and increases in 

financial and technology transfers. Barriers associated with reaching 

this potential include a lack of competitive markets, barriers to trade, 

ill-defined or undefined property rights, and a lack of adequate 

information.

• Socio-economic potential–This is the level we could achieve 

through the adoption of changes in behavior, lifestyles, social 

structures and institutions. Barriers associated with reaching this level 

include our social norms, individual habits, attitudes, values, and 

vested interests.

Adaptive capacity depends 

on a community’s 

wealth, access to 

technology, effective 

and stable institutions, 

efficient mechanisms for 

disseminating information, 

an equitable distribution 

of power, and a wellfunctioning social system...
80

• Technological potential–This is the level we could achieve 

through implementation of technology with demonstrated success 

in combating the effects of climate change. Barriers to achieving 

this level include limited availability and knowledge about new 

technologies.

• Physical potential–This is the theoretical upper bound to what we 

could achieve through mitigation strategies.

Actualizing our mitigation potential rests on overcoming barriers 

in all levels of potential adoption of mitigation strategies. E.g., energy 

production from nuclear power plants is a demonstrated technology that 

may be underutilized, mostly due to socio-economic barriers that show 

an unwillingness to trade climate risk with the perceived risks of nuclear 

power plants (Burgman 2005).

There are several approaches that we could take to reduce or mitigate 

climate change (Hardy 2003):

• Capture or sequester carbon emissions;

• Reduce global warming or its effects through geo-engineering;

• Enhance natural carbon sinks;

• Convert to carbon-free and renewable energy technologies; or

• Conserve energy and use it more efficiently.

Within each of these mitigation approaches, there are several options. 

E.g., forestry practices that increase the sequestration of carbon on 

forestland (Richards and Stokes 2004: 6) include (1) afforestation of 

agricultural land; (2) reforestation of harvested or burned timberland; (3) 

change of forestry management practices to emphasize carbon storage; (4) 

adoption of low impact harvesting methods to decrease carbon release; 

(5) lengthening forest rotation cycles; (6) preservation of forestland from 

conversion; (7) adoption of agroforestry practices; (8) establishment 

of short-rotation woody biomass plantations; and (9) urban forestry 

practices. While mitigation strategies will not reverse the climate change 

trend, they may at least slow it down (McCarthy et al. 2001) and help 

avoid its worst effects (Smith et al. 2003). E.g., although conserving and 

sequestering carbon is not necessarily permanent, it may provide more 

time to develop other options by delaying climate change (IPCC 2001). 

Regardless, there will likely be effects from climate change on ecological, 

social and economic systems. We will have to adapt to these changes.

Adaptation

Adaptation is a necessary component to any response to climate 

change (Smith et al. 2003). It is not a new concept in that we are 

continually adapting to our changing surroundings. Adaptation is a 

“conscious ongoing process of monitoring, evaluating, and learning to 

make decisions. These decisions might involve changes to processes, 

practices, or structures to reduce potential vulnerabilities and damages, or 

to take advantage of new opportunities that may emerge” (Cohen et al. 

2004: 152). In other words, adaptation is “any adjustment in natural or 

human systems that moderates harm and exploits beneficial opportunities 

Actualizing our mitigation 

potential rests on 

overcoming barriers in all 

levels of potential adoption 

of mitigation strategies. 

While mitigation strategies 

will not reverse the climate 

change trend, they may at 

least slow it down...and 

help avoid its worst effects...
81

associated with observed or expected impacts of climate change” (Klein 

and Smith 2003: 317). The adaptive capacity of a system depends on its 

resilience, stability, robustness, flexibility and other characteristics (Smit 

and Pilifosova 2003: 22).

While mitigation strategies may be implemented at the local level, 

they target the broader issue of greenhouse gas concentrations in the 

atmosphere. Adaptation, on the other hand, addresses localized impacts 

of climate change (IPCC 2001). What might work in one area or for a 

particular group may not work elsewhere (Smit and Pilifosova 2003). 

Therefore, even though we might conclude that society can adapt to 

climate change does not mean there will be no localized losses. 

Even where regions on the whole may be able to successfully adapt 

to a limited climate change, specific individuals and communities could 

still be displaced and harmed by climate change. Of particular concern 

are those communities that have strong ties and associations with specific 

areas and resources that are exposed and sensitive to climate change (e.g., 

through sea-level rise, increased drought, extreme heat), derive a high 

share of their income from climate sensitive activities such as agriculture 

or fishing, and lack financial and other means to adapt to change 

(Easterling et al. 2004: 19).

Cohen et al. (2004: 153) identified several characteristics of 

adaptation to climate change:

• It can be undertaken by individuals, communities, government, 

private sector;

• It can be either autonomous or planned;

• It can be either proactive (anticipatory) or reactive (responsive);

• It can be implemented at the local, regional, national and 

international scales; and

• It can be market-based, behavioral, legislative, institutional, 

structural, operational, or technological.

Three primary approaches to tailoring adaptive measures to local 

needs have been identified (Smit and Pilifosova 2003: 24). First, we 

need to “address real local vulnerabilities, so that stakeholders buy into 

the issue and are interested in reducing vulnerabilities of which they 

are well aware.” Second, we need to “involve real stakeholders early and 

substantively, so that any assistance is directed at known vulnerabilities, 

and adaptation initiatives are realistic and designed to be consistent 

with existing institutions and decision processes.” And third, we need 

to “connect with local decision-making processes, so that adaptation 

initiatives are developed relative to other conditions, are ‘mainstreamed,' 

to the extent possible, and have the best possible chance of actually being 

implemented.”

Adaptation plays a central role in the overall damages incurred by 

social and economic systems due to climate change. Economic studies 

that did not account for adaptation estimated net losses associated with 

climate change for the United States. However, when adaptation is 

incorporated into economic models, results have tended to show small net 

Even where regions on 

the whole may be able 

to successfully adapt to a 

limited climate change, 

specific individuals and 

communities could still be 

displaced and harmed by 

climate change. 
82

gains from moderate climate changes over the next century (Mendelsohn 

2000, Smith 2004). In Mendelsohn (2000: 584), several market sector 

adaptations to climate change are identified, including:

• Agriculture–private strategies

o Alter crop species, alter timing, improve or extend irrigation

• Agriculture–public strategies

o Engineer resistant/tolerant plants

• Sea level rise–private strategies

o Depreciate vulnerable buildings

• Sea level rise–public strategies

o Build sea walls as needed, enrich beaches as needed

• Forestry–private strategies

o Harvest vulnerable trees, plant new tree varieties, intensify 

management

• Energy–private strategies

o Expand cooling capacity, improve insulation, develop cool 

building designs

• Energy–public strategies

o Develop new building codes

• Water–private strategies

o Invest in water efficiency

• Water–public strategies

o Shift water to high value uses, divert/store more water, re-assess 

flood zoning

• Biodiversity–public strategies

o Move endangered species, manage landscapes, plant adapted 

species

• Health–private strategies

o Prepare for extreme weather events, avoid insect bites

• Health–public strategies

o Control disease carriers, treat infected people, control diseased 

ecosystems

• Aesthetics–private strategies

o Adapt behavior (e.g., recreation)

• Aesthetics–public strategies

o Educate people of adaptive options

Mitigation and adaptation are complementary approaches that need 

to be considered jointly with a changing climate (Easterling et al. 2004). 

If mitigation and adaptation are treated as substitutes for one another, 

then the costs of policies and programs targeting climate change are likely 

to increase with little change in climate risks and the benefits derived from 

reducing these risks (Kane and Yohe 2000). Regardless of our approach 

Mitigation and adaptation 

are complementary 

approaches that need to be 

considered jointly with a 

changing climate...
83

to climate change, there will be costs associated with it (Easterling et al. 

2004, Mendelsohn et al. 1999, Smit and Pilifosova 2003).

Areas of Further Research

Four research themes that are relevant to the climate change problem 

include policy-relevant science, micro-scale analyses, valuation of nonmarket changes, and local adaptation.

Policy-Relevant Science

Scientific understanding could be more effective in its role in the 

decision making process. In particular, the lack of knowledge regarding 

localized impacts from climate change leaves decision makers on the 

outside looking in, or attempting to make locally relevant decisions based 

on globally or nationally defined trends (NRC 1999). Therefore, 

research should pursue three related aims: improving methods 

for valuing nonmarket goods; improving analytical methods for 

integrating multiple types of decision-relevant information (e.g., 

integrated assessment models, cost-benefit analyses); and developing 

decision processes that effectively combine analytical, deliberative, 

and participatory approaches to understanding environmental 

choices and thus guide scientists toward generating decision-relevant 

information (NRC 1999: 59). 

Risk and uncertainty of events occurring and their relative impacts 

need to be better conveyed to decision makers and the public, in 

particular concepts of likelihoods, confidences, and ranges of uncertainty 

(IPCC 2001). It is well-known that scientific measures of risk and lay 

perceptions of risk often diverge. Both expert and lay perceptions of 

risk are affected by psychological, social, cultural and political factors, 

including uncertainty regarding the consequences of climate change 

and how risks are distributed among affected populations (Burgman 

2005, Slovic 1999). Uncertainties about the risks of climate change are 

compounded by uncertainty due to climate variability. 

Better means of communicating risks to lay audiences seems 

appropriate if public discourse is to be informed by scientific findings 

(which includes measures of risk and probabilities). This discourse on 

climate change and its associated risks is important if perceptions of risk 

are socially constructed. Slovic (1999) argues that public participation, 

especially for those people most affected by climate change, in risk 

assessment and risk decision making is critical to defining strategies 

to deal with hazards and risks. Public participation at all levels of risk 

assessment and decision making would make “the decision process more 

democratic, improve the relevance and quality of technical analysis, and 

increase the legitimacy and public acceptance of the resulting decisions” 

(Slovic 1999: 689). 

Most studies estimating long-term impacts of climate change assume 

risk neutrality of decision makers. Research on risk-averse behavior in 

environmental decision-making in the context of climate change may 

...the lack of knowledge 

regarding localized impacts 

from climate change leaves 

decision makers on the 

outside looking in, or 

attempting to make locally 

relevant decisions based 

on globally or nationally 

defined trends...

Better means of 

communicating risks to lay 

audiences seems appropriate 

if public discourse is to 

be informed by scientific 

findings...
84

result in different strategies to deal with climate change and how to 

package climate change policies (Davidson et al. 2003, Mendelsohn 

2001). A good starting point for assessing strategies to deal with risks from 

environmental change is the natural hazards literature (Smit et al. 2000).

Micro-Scale Analyses

Most research on climate change is at a macro-scale (i.e., global, 

national, or regional scale). These broad-scale efforts should continue as 

models are refined, additional data are gathered or become available, and 

trends in climate patterns become realized. However, more information 

at local levels (micro-scale analyses) is needed. Some social groups may 

be at greater risk, not solely because of their geographic location in a 

region of high climate sensitivity, but also because of economic, political 

and cultural characteristics (Davidson et al. 2003). Thus, at the regional 

or local scale, uncertainty regarding potential impacts of climate change 

increases (Mendelsohn 2001, Miller and Gloss 2003, Shugart et al. 

2003, Smith 2004, Travis 2003, Wallentine and Matthews 2003). E.g., 

Mendelsohn (2001: 198) notes that 

climate change itself is not likely to be uniform. Changes in 

precipitation especially could vary widely on a local scale. Ecological 

impacts may be different in the southern edge of a region than in the 

northern edge. Economic activity and populations vary widely across 

regions. For all these reasons, one should expect that the experience 

of every household could vary within a region. 

However, micro-scale analyses should be conducted with recognition 

that they are nested within a larger scale. Sustainable management 

involves multiple values and temporal and spatial scales. Only within 

the appropriate scale can sustainable management balance the needs of 

ecosystems with economic efficiency and distributional equity.

Non-market Valuation

Several authors have identified a need for climate change and 

policy-relevant measures of the effects on non-market resources such 

as health, aesthetics, recreation, and species losses (Loomis and Crespi 

1999, Mendelsohn 2001, Mendelsohn et al. 1999, Mendelsohn and 

Neumann 1999, NRC 1999, Pearce et al. 1996, Smith 2004). Most 

scientific evidence regarding the likely impacts of climate change are for 

sectors with markets (see table 1). Estimates of non-market impacts of 

climate change are needed to help guide decision making through use 

of informative tools such as integrative models and cost-benefit analyses 

(Chee 2004, NRC 2005). Economic estimates of non-market impacts 

would aid decision makers as they evaluate climate change policies by 

elaborating on the trade-offs associated with their choices. Climate change 

may be a good proving ground for many of the well-established economic 

valuation methods and newly emerging approaches, in particular due to 

its complexity, uncertainty and potentially non-linear nature of impacts 

(NRC 2005). 

Recreation is likely the primary means through which most people 

will directly experience climate change (Wagner 2003). How people 

Climate change may be a 

good proving ground for 

many of the well-established 

economic valuation methods 

and newly emerging 

approaches, in particular 

due to its complexity, 

uncertainty and potentially 

non-linear nature of 

impacts...
85

respond in their recreation behavior may be a strong indicator of their 

knowledge of and attitudes toward climate change (Irland et al. 2001). In 

particular, will people support the relocation of recreation opportunities 

and facilities, especially when relocation is subject to significant costs 

(Loomis and Crespi 1999)? E.g., the ski industry may be sustained in the 

short-term by relocating facilities either higher in elevation or to another 

area where adequate snow is expected. 

The loss of species and termination of ecosystem services may be a 

critical threshold that we are unwilling to cross (Farber et al. 2002). E.g., 

if a certain species requires a minimum amount of habitat to survive and 

changes in climate reduce habitat below the critical threshold, then a nonlinear response (i.e., extinction) is likely to happen. Is this an acceptable 

outcome, especially if the risk of it occurring can be reduced through 

proactive management? What types of values and how much are they 

willing to trade for a reduction in the risk (probability) of an irreversible 

event? Are there critical thresholds that we need to manage against 

regardless of public opinion? How will people and communities respond 

to worst-case scenarios (NRC 1999, Smith 2004)?

Local Adaptation

We also need more applied research on how adaptation could occur 

(Davidson et al. 2003, Joyce et al. 2000, Mendelsohn and Markowski 

1999, NRC 1999, Smith 2004). Potential adaptation responses to 

recent and historical events may provide important insights into likely 

adaptation responses to climate change at the local level. People have 

adapted their behavior due to other environmental events such as fish 

consumption advisories, smog alerts, beach closures and fish catch rates 

(Joyce et al. 2000, NRC 1999). A changing landscape due to climate 

change is important given evidence that migration patterns into rural 

areas are linked to the spatial distribution of natural amenities over the 

past two centuries (Deller et al. 2001, Rosenberger and English [In 

press]). What are the likely future migration patterns due to climate 

change, and how might these patterns affect efforts to reduce climate 

change or their impacts on social, economic and ecological systems?Most 

research to date is concerned with macro-scale models of climate change 

and economic systems. More localized studies with disaggregated data are 

needed since adaptation will occur at the local level (Davidson et al. 2003, 

Mendelsohn and Markowski 1999, Smith 2004). Adaptation is place 

and culture specific and can only be identified through place and culture 

specific research (Smit and Pilifosova 2003). Research on local adaptation 

should include those most affected by climate change and those with 

decision making responsibilities (Klein and Smith 2003).

Conclusions

There is little doubt that as climate continues to change we will 

see changes in our ecological, social and economic systems as a result. 

However uncertain we are regarding changes in ecological systems due to 

a changing climate, uncertainties about our social and economic systems 

are greater. This is important given humans are motivated by those values 

What are the likely future 

migration patterns due to 

climate change, and how 

might these patterns affect 

efforts to reduce climate 

change or their impacts 

on social, economic and 

ecological systems?
86

they hold. As climate change threatens these values, we ought to see 

people respond in an effort to protect them. Other human activities, such 

as deforestation and energy consumption are influenced by population 

growth, economic growth, values and belief systems, institutions and 

policies, and the dynamic interaction among them (NRC 1999). Not only 

are these factors intimately linked to the climate change problem, but they 

also create barriers to solutions for the problem (IPCC 2001). Human 

responses to climate change may not be effective or efficient, especially 

without full information (Hanemann 2000). 

The future is not bleak; there are other reasons to act now, regardless 

of whether climate change is perceived to be real. Responding to 

climate change can result in significant benefits. The US EPA (2002) 

summarized several benefits we can expect from reducing greenhouse 

gas emissions. Public health benefits from reducing fossil fuel use leads 

to less air pollution and associated respiratory problems. Environmental 

quality improves through better air quality, lower environmental costs 

associated with air pollution, improved water quality from reduced 

nitrogen deposition, along with a reduction in the effects of climate 

change on ecological systems. Our economy benefits by reducing energy 

costs to households through increasing energy efficiency, lower material 

and disposal costs associated with increased recycling, greater reliability 

of alternative energy sources, and increased profits and jobs associated 

with businesses that incorporate energy efficient technologies in their 

production process and products and provide alternative energy sources. 

Land use changes result in more walkable cities and more efficient use of 

land including conservation of open space around cities, which directly 

contribute to human health and well-being (Rosenberger et al. 2005). 

Urban forestry benefits include greener cities through tree planting 

programs that sequester carbon, filter air pollution and water runoff, 

reduce summer cooling costs, and result in more attractive communities. 

Managed forest benefits result from sustainably managing forests for longterm carbon storage, a sustained wood supply, and increased ecological 

benefits associated with sustainable forestry practices. Agriculture benefits 

by reducing energy costs to farmers from improved energy efficiency in 

operations and equipment, conservation tillage, and alternative practices 

such as strategic fertilizer applications. New sources of income for farmers 

may be realized through the supply of crops for biofuels and energy 

production from livestock waste. In many ways, several mitigation and 

adaptation strategies are win-win propositions. The challenge is to derive 

broad support for policies and programs targeting climate change. 

Acknowledgments

This paper was presented at the Bringing Climate into Natural 

Resource Management Conference, Portland, OR, June 28-30, 2005. This 

research was supported in part by funds provided by the Pacific Northwest 

Research Station, Forest Service, U.S. Department of Agriculture. This 

paper benefited from comments on an earlier draft by Richard Haynes 

and Mark Sperow. Any remaining errors are the sole responsibility of the 

author.

The future is not bleak; 

there are other reasons to act 

now, regardless of whether 

climate change is perceived 

to be real. 

Environmental quality 

improves through better air 

quality, lower environmental 

costs associated with air 

pollution, improved water 

quality from reduced 

nitrogen deposition, along 

with a reduction in the 

effects of climate change on 

ecological systems. 
87

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91

The Challenges of Bringing Climate into 

Natural Resource Management: A Synthesis

Linda Joyce1 and Richard Haynes 2

1Research Project Leader, USDA Forest Service, Rocky Mountain Research Station, 240 West Prospect, Fort Collins, CO 80526. Email: ljoyce@fs.fed.us

2

Program Manager, USDA Forest Service, Pacific Northwest Research Station, P.O. Box 3890, Portland, OR. Email: rhaynes@fs.fed.us

Tom Iraci, USDA Forest Service

James C. Leupold

U.S. Fish and Wildlife Service

Gary Kramer

U.S. Fish and Wildlife Service
92

Abstract

Here we synthesize and extend observations and recommendations 

from the speakers at the 2005 workshop titled “Implications of Bringing 

Climate into Natural Resource Management in the Western United 

States.” Discussions there illustrated the complexity of global climate 

change and the need for managers to consider how the impacts of climate 

change will unfold across regional and local landscapes. The geographical, 

ecological, political, and socio-economic differences between the West 

and the East suggest that approaches to bringing climate into natural 

resource management will be unique to the West. These approaches will 

vary reflecting differences in threat perceptions among scientists, land 

managers, landowners, interested stakeholders and the public all who play 

different roles in governing actions across forested ecosystems. The various 

discussions revealed that there are many potential solutions but none 

are simple. Managers, however, are already responding to those aspects 

of global climate change that they can see or perceive. Eventually the 

accumulation of these local actions will shape our future. 

Keywords: Climate change, forest and range management

Introduction

The Western United States is a rich diverse land of wide open spaces, 

ranging from the Great Plains grasslands to the Rocky Mountain forests 

to the Intermountain shrublands and deserts to the rich valleys of 

California and Oregon, to the coastal forests of the Pacific Northwest. 

Through exploration, industrial development and human population 

expansion, humans have capitalized on the natural resources of the 

western environment. Early settlers exploited small-scale opportunities 

such as hunting and trapping. Mining pulled rich ores from the earth and 

modified the landscape through wood harvest for mining—altering stream 

bed structure and riparian areas all over the West—and energy uses. The 

wide open spaces brought the livestock industry, sheep and cattle herds, 

cattle drives, and alterations in native vegetation and the introduction 

of exotic plant species. Agricultural expansion capitalized on spring 

time mountain runoff, developed large irrigation systems, and reservoirs 

to serve the expanding human populations as well as the agricultural 

industry. Forest products industries quickly developed as railroads opened 

access to vast mature softwood stands and connected domestic and 

international markets. The industry, initially based on private timber, 

evolved on a large scale to one increasingly reliant on public timber, 

following World War II. It was an early adopter of advanced materials 

handling and processing technologies. Post World War II also brought 

new demands by an increasingly wealthy society for increased recreational 

opportunities, such as winter skiing, summer tourism, and second homes 

in scenic areas. In the late 20th century, attention focused on natural 

resources, and past examples of western land management were often the 

basis for a rethinking of land management on public and private lands 

(see Wilkinson 1992 for a discussion of these changes). 

Through exploration, 

industrial development 

and human population 

expansion, humans have 

capitalized on the natural 

resources of the western 

environment. 
93

Today, the rural nature of the western landscape continues to change: 

scenic mountain valleys are being developed, urban areas are expanding 

into the deserts and grasslands around the major metropolitan centers, 

and settlements in the Great Plains and the Interior West are declining. 

The relationship between the humans and the western environment 

has changed over time as settlers became aware of their impact on the 

landscape, coupled with reoccurring droughts, potential for wildfire, 

and the periodic outbreaks of insects on forests and grasslands. That 

relationship and understanding will likely be challenged as the West faces 

potential changes in its climate. 

Natural resource managers, scientists and policy makers from private 

and governmental agencies gathered for 21⁄2 days in June 2005 to explore 

the implications of bringing climate into natural resource management in 

the western United States. In this paper, we synthesize observations and 

recommendations of speakers for resource management approaches to 

climate change, and our own thoughts on this challenge.

In the United States, the West 

is Different from the East

The Western United States was repeatedly described in this workshop 

as very different from the Eastern United States. In terms of forestland 

ownership, 81 percent of the West is in federal land management versus 

only 19 percent in the East. In the West, elevation often fragments the 

landscape with higher elevations mostly in federal ownership and the 

valleys are privately owned where agriculture is feasible. In terms of land 

cover, 38 percent of forests in the United States are found in the West. 

Rangeland accounts for one third of the land in the United States, but the 

Western United States holds the majority of that rangeland, 80 percent. 

These ecosystems include the Great Plains grasslands, the savannas 

in Texas, sagebrush steppe and shrublands in the Great Basin, alpine 

meadows, wetlands, and southwestern deserts. 

The highest mountains ranges in the United States occur in the West 

with the Rocky Mountains and the Pacific Coastal Ranges reaching 

more than 14,000 feet above sea level. The West also holds the lowest 

elevation with Death Valley at 282 feet below sea level. The terrain of 

the West strongly influences the environment, the vegetation and the 

habitats of animals. In the mountains, north facing slopes often have a 

forested vegetation whereas the south facing slopes may have only shrubs 

and grasses. Distances between cool moist environments and warm dry 

environments can be remarkably short. 

The social and economic conditions in the West are often described in 

terms different than those for the East. In 2000, the West accounted for 

23 percent of the United States population but 53 percent of those people 

lived in California. It is often thought of as a place of wide open spaces yet 

82 percent of its population lives in urban areas (as opposed to 77 percent 

of the population in the East). It contains rapidly growing metropolitan 

areas like Phoenix or Las Vegas that attract both economic as well as 

lifestyle migrants. It also contains an emerging frontier where population 

The relationship between 

the humans and the western 

environment has changed 

over time as settlers became 

aware of their impact on 

the landscape, coupled 

with reoccurring droughts, 

potential for wildfire, and 

the periodic outbreaks 

of insects on forests and 

grasslands. 
94

densities are less than 6 people per square mile. Western states account 

of 24 percent of the U.S. economic activity in 2004. The diversities of 

western economies mirrors that for the United States but with a slightly 

higher proportion of some states economies being accounted for by 

softwood lumber manufacturing and mining than Eastern States. In 

addition, the services sector is slightly large in the West than in the East. 

These geographical, ecological, political, and socio-economic 

differences between the West and the East suggest that approaches to 

bringing climate into natural resource management will be unique to the 

West. For example, the complex terrain makes it challenging to model 

fine scale climate change using the current large scale climate models. 

Additionally, this complex geography and the difficulty of access in remote 

areas of the West have limited adequate monitoring of weather and 

ecological phenomena. The intermingling of public and private land raises 

challenges to managing the large diverse landscapes.

Past and Future Climates 

in Western United States

Weather is the short-term variation in temperature, precipitation, 

humidity, wind, and cloudiness. Climate is the long-term description of 

weather. Plants and animals adapt to local climates, to the summer rains, 

snowfall, snow depth, the direction of wind and wind speed, the timing of 

last frost in spring or the first in fall, and soil temperature and moisture. 

Western climates are variable across space and time, much more so than 

eastern climates. 

Observations of climate in the West for the last 100 years indicate that 

we may be seeing a warming trend already (see Redmond, this report, for 

an extensive discussion of western climate). Western winter and spring 

temperatures show the strongest trend in warming, a point also stressed 

by Phil Mote in his presentation (see figs. 1 and 3, Redmond, this report). 

Climate models suggest that these warming trends will likely continue 

into the 21st century, see figure 4 in Redmond (this report). Precipitation 

over the last 100 years in the west shows little trends and great variability 

(fig. 7, Redmond, this report). Across several climate models scenarios, 

potential future precipitation in the West shows no trend up or down, but 

does exhibit more variability, interannual as well as multi-year variability. 

Observed Changes in Western 

Ecosystems in Relation to Climate

The human influence on climate and water resources in the West is 

emerging from numerous studies (fig. 1). Phil Mote described studies of 

changes in western watersheds. From 1950 to 1997, snowpack on April 

1 showed a decline throughout most of the western watersheds. These 

snowpack changes led to documented earlier springtime flows and lower 

summer time flows in streams from mountainous areas. Spring time 

runoff is critical to water needs for agriculture and urban areas in the 

West. Phil Mote also showed the West is very vulnerable, with modest 

These geographical, 

ecological, political, and 

socio-economic differences 

between the West and 

the East suggest that 

approaches to bringing 

climate into natural resource 

management will be unique 

to the West. 

The human influence on 

climate and water resources 

in the West is emerging 

from numerous studies...
95

winter temperature increases of only 2-4°F, to shifts in snow to rain events. 

Both Redmond (this report) and Mote showed future projections under 

several different possible climate scenarios where warming temperatures 

led to declines in the western snowpack.

Joel Smith presented recent research focused on the climate-sensitive 

behaviors of plants and animals, such as breeding, emergence from 

hibernation, seasonal migration, productivity, and changes in species 

ranges. Many of these changes (fig. 2) have been documented in the 

Western United States. Examples include earlier egg laying of the first 

clutches in Mexican Jays, earlier emergence from hibernation by marmots, 

northern expansion of the Sachem Skipper butterfly, and the rising 

dominance of warm-water species in Monterey inter-tidal community. 

In each case, a climate indicator tied to the behavior or the plant or 

animal species also had changed. For example, water temperature in 

Monterey Bay has increased by 2°F over the 1939-1990 period, bringing 

about a corresponding shift in species dominance. Yet, with these 

individual examples, can we conclude climate change is responsible for 

these observed impacts at the scale of the Western United States? Joel 

Smith described large scale studies of thousands of species where the 

scientists concluded that climate changes can be linked to the observed 

global biological changes and the changes in North American plants and 

animals. However, meta-studies at the scale of the Western United States 

are needed to definitely conclude that the impacts in this region are clearly 

attributable to climate change. The West is experiencing other factors that 

affect regional climate and the landscapes, but, the observed changes on 

the western landscape are consistent with projected climate changes.

Figure 1—A diagram of the atmospheric-biospheric interactions. Source: Trenberth et al. 1996, p. 55.

Changes in the Atmosphere:

Composition, Circulation

Changes in the

Hydrological Cycle

Atmosphere

Changes in 

Solar Inputs

Aerosols

H2O, N2, O2 , CO2, O3, etc.

Clouds

River

Lakes

Biomass

Land

Sea-Ice

Ocean

Land-Biomass

Coupling

Changes in the Ocean:

Circulation, Biochemistry

Changes in/on the Land Surface:

Orography, Land Use, Vegetation, Ecosystems

Air-Ice

Coupling

Heat

Exchange

Wind

Stress

PrecipitationEvaporation

Terrestrial

Radiation

Air-Biomass

Coupling

Human

Influences

Ice-Ocean

Coupling

...meta-studies at the scale 

of the Western United States 

are needed to definitely 

conclude that the impacts 

in this region are clearly 

attributable to climate 

change.
96

Potential Changes in Western Ecosystems 

and Economies Under Climate Change

Scientists have explored potential changes in western ecosystems and 

economies through the use of simulation models and different projected 

future climates. Global general circulation models project different future 

climate scenarios as a function of assumptions about future emissions of 

trace gases such as carbon dioxide, methane, and nitrous oxides. Redmond 

(this report) described some of those future scenarios. As the amount of 

carbon dioxide is likely to double over the next century, scientists have 

also studied the responses of plants to higher amounts of carbon dioxide.

The impact of higher atmospheric concentrations of carbon dioxide 

on plants is the focus of Jack Morgan’s research at the Agricultural 

Research Service. While plant production increases when plants are 

grown under higher levels of carbon dioxide, the response varies by 

climate, plant community, and soil fertility of the grassland ecosystem. 

The increased response in plant production was seen only in the dry years 

at a sub-humid grassland of Kansas, across dry, normal and wet years on 

the semi-arid grassland in Colorado, and only in wet years in the arid 

grassland of Nevada. Across individual species, the response could be 

increased biomass production, greater seedling response, or increased seed 

production. For these grasslands, a more disconcerting response was a 

decline in the quality of the vegetation as forage, less nutritious and lower 

Figure 2—Examples of climate-sensitive behaviors of plants and animals.

Plants

 First leaf out in spring

 Flowering

 Senescence at the end of the growing season, arrival of fall colors

 Plant productivity

 Dominance of particular plant species in plant communities

 Extension of geographic ranges through more favorable climate

Animals

 Breeding, courtship, nesting, egg laying 

 Life cycles of insects, from two year to adult stage to one year

 Seasonal migration

 Emergence from hibernation

 Animal productivity

 Extension of ranges through more favorable climate

Ecosystem Dynamics

 Nutrient availability

 Decomposition in the soil

Examples of Climate Sensitive Behaviors 

of Plants and Animals
97

digestibility of the forage. This decline in forage quality has implications 

to both domestic livestock and wildlife.

Lewis Ziska described relationships between climate, carbon dioxide, 

and invasive plants. In one experiment, he explored the response of 

six invasive weeds—Canada thistle (Cirsium arvense (L.) Scop.), field 

bindweed (Convolvulus arvensis L.), leafy spurge (Euphorbia esula L.), 

perennial sowthistle (Sonchus L.), spotted knapweed (Centaurea stoebe

L.), and yellow star-thistle (Centaurea solstitialis L.)—to concentrations 

of carbon dioxide that corresponded to the beginning of the 20th century, 

current levels, and concentrations projected for the end of the 21st century. 

The likely future concentrations stimulated plant biomass on the average 

by 46 percent with the largest response observed for Canada thistle (fig. 

3). Perhaps even more intriguing was the response from the early 20th

century to present, 110 percent. This study suggests the possibility that 

recent increases in atmospheric carbon dioxide during the 20th century 

may have been a factor in the growth of these invasives. Lewis Ziska 

also described an experiment along the rural to urban gradient where 

temperature and atmospheric carbon dioxide concentrations reflect what 

the future might be—urban areas currently reflecting warmer climate 

and higher carbon dioxide concentrations than rural areas. Early results 

suggest the warmer environment with higher levels of carbon dioxide is an 

excellent environment for weedy species. 

Scientists exploring the potential impacts of future climate change 

on ecosystems and economies have used large scale models to simulate 

different future climates. Neilson (this report) describes the potential 

futures of North American ecosystems under climate change using the 

MC1 Dynamic General Vegetation Model (DGVM) and six future 

climate scenarios (3 General Circulation Models X 2 emission scenarios). 

His results show an increase in carbon sequestration in the late 20th

century and briefly early in the 21st century, the result of increased 

precipitation, enhanced water-use efficiency and mild temperature 

increases. He shows that these ‘greening’ processes were overtaken by the 

exponential effects of increasing temperature on evaporative demand and 

respiration, producing a subsequent decline in ecosystem productivity 

(Neilson, this report). 

There has been limited work describing the potential western socioeconomic impacts of changing climate (Rosenberger, this report). Much 

of this work is very general given the lack of specificity in possible impacts 

to determinants of social and economic activities. At the same time land 

managers and others are responding to changing climate by adapting or 

modifying their management actions. For example, some ski areas are 

considering or have added snow making machines to both extend seasons 

and to adapt to perceived variability in snow fall. At the same time we are 

seeing increased amenity based migration to places previously considered 

too remote or inhospitable (such as Prince of Wales Island, Alaska) as 

either perceptions or mitigation activities change. Rosenberger (in this 

report) described that the biggest winners from climate change are likely 

to be agriculture and summer recreation while the biggest losers are likely 

to be water resources and energy sectors. 

Early results suggest the 

warmer environment with 

higher levels of carbon 

dioxide is an excellent 

environment for weedy 

species. 

...land managers and 

others are responding 

to changing climate by 

adapting or modifying their 

management actions. 
98

Since 1995, the various RPA timber Assessments have included 

different scenarios examining the effects of climate change on U.S. forests 

and forest products markets (see Haynes 2003, Haynes and others 1995, 

Haynes and others, in prep.; Joyce and others 1995). In these scenarios 

climate change is expected to involve temperature increases 3 to 5°F in the 

East and up to 7°F in the West and increased precipitation, except for the 

Gulf Coast and the Pacific Northwest. The effects of climate change are 

modeled by modifying the growth rates of different forest types. In general 

these scenarios have shown that climate and elevated carbon dioxide act 

to augment growth in nearly all regions. Both softwood and hardwood 

growth on private lands expand steadily with particularly large percentage 

changes in the western regions. As in previous climate impact analyses, 

the regional impacts vary geographically and can be quite different from 

the national average results, reflecting regional climate changes. Because 

the inventory changes are gradual, their impacts on private timber harvest, 

timber prices and ultimately on product markets and prices in both 

scenarios are relatively small. For example, total U.S. softwood sawtimber 

harvest and annual softwood lumber production both increase by about 

+0.1 to 0.4 percent. Impacts in national product markets are muted given 

extensive inter-regional and international substitution (for more details see 

Haynes and others, in prep.).

Figure 3—Six invasive weeds, Canada thistle, field bindweed, leafy spurge, perennial sowthistle, spotted 

knapweed, and yellow star thistle were grown from seed at either 284, 380 or 719 mmol mol-1 carbon 

dioxide through the vegetative period. The concentration of 284 reflects the atmospheric concentration 

of carbon dioxide in the early 20th century, and the 380 reflect the current concentration. At 54 days, 

the average stimulation of plant biomass among invasive species during the 20th century was 110 

percent. The response to future concentrations of carbon dioxide (not shown here) was an average of 46 

percent (Ziska 2003). Invasive weeds

Percent increase in total biomass at 54 DAS

285-380 μmol mol

-1

0 50 100 150 200

Canadian thistle

Perennial sowthistle

Yellow star thistle

Leafy spurge

Field bindweed

Spotted knapweed

x = 110.1 —

Steve Sutherland 

spotted knapweed 

Peggy Greb, USDA 

Agricultural Research Service, 

www.ipmimages.org

yellow star-thistle

Norman E. Rees

USDA Agricultural Research Service

www.forestryimages.org

leafy spurge

Mary Ellen (Mel) Harte

www.forestryimages.org

field bindweed
99

Current Challenges of Natural 

Resource Management 

Within the last 20 years, western land managers have not only faced 

increases in invasive plants but many other seemingly unprecedented 

natural disturbances. Recent catastrophic fires have been described 

as outside of the known behavior, intensity, and extent of past fires. 

Managers have also faced droughts in the Southwest that appear to rival 

past droughts. Water and aquatics management has had to respond to 

the reduced snowpack throughout the West. Insect patterns appear to 

represent significant change from historical records. The question was 

raised as to whether these disturbances are symptoms of the underlying 

changes associated with climate. 

Jesse Logan described the implications for bark beetle management 

under a changing climate. Jesse reviewed the current large outbreaks 

of spruce beetle (Dendroctonus rufipennis Kirby) in North America, 

the pinyon ips (Ips spp.) in the Southwest, and mountain pine beetle 

(Dendroctonus ponderosae Hopkins) throughout Western United 

States. Building on his extensive research on the relationship of climate 

and beetle biology, he described simulations showing that increasing 

temperatures enhances beetle populations. He also presented results 

showing beetles occurring at higher elevations than previously seen—the 

range expansion of mountain pine beetle into high elevation white pines. 

He concluded that we are beyond demonstrating that something (climaterelated) is occurring and that it is time to start formulating a management 

response to this changing environment in western high-elevation forests. 

Mike Pellant described the challenges of managing Great Basin 

rangelands that have been dramatically altered by invasive plant species. 

The exotic annual grasses have altered the vegetation composition and the 

fire frequency in the Great Basin. Wildfires are now a common event in 

the Great Basin, and given the nature of the vegetation changes, wildfires 

will continue to increase in size and frequency, with or without climate 

change. Thus, without restoration, the ecosystems dominated by these 

annual grasses will continue to increase and the values associated with 

native plant communities, such as wildlife habitat, and the uses of these 

communities will continue to decline. He referred to this situation as 

the downward spiral from native plant communities to communities 

with cheatgrass (Bromus tectorum L.) and perennial invasive forbs, and 

ultimately to an endpoint of degradation unknown yet (fig. 4). The 

ecological integrity of the Great Basin is rapidly changing as a result the 

combination of invasive species, wildfires and increasing human-related 

disturbances. Restoration of altered western rangeland ecosystems is 

currently costly, yet if land management does not begin to restore these 

altered ecosystems and maintain healthy plant communities, weeds and 

wildfires will continue to control the ecological and economic health of 

the Great Basin. And the challenges could be even greater under an altered 

climate. But restoration is made difficult because species selected need to 

be adapted to potentially warmer or drier future environments.

Within the last 20 years, 

western land managers have 

not only faced increases 

in invasive plants but 

many other seemingly 

unprecedented natural 

disturbances.

The ecological integrity of 

the Great Basin is rapidly 

changing as a result the 

combination of invasive 

species, wildfires and 

increasing human-related 

disturbances.
100

Can Current Goals of Resource Institutions 

be Sustained Under Climate Change? 

In the broader community of natural resource management, 

institutions set goals and strategies for their resources based on interest 

or legal mandate. Institutional objectives are likely set without regard to 

climate or with assumptions that climate, though variable is not changing. 

Several speakers identified the challenge of whether and how to readjust 

institutional goals under a changing climate. 

Steve Malloch used metaphors to describe how institutions might 

face a potential change in their objectives: brakes, seat belts, and chickens. 

Brakes were the metaphor for prevention and mitigation, keep the 

institutional objectives but bring a focus on how to stop the change from 

occurring or going further. Seat belts were the metaphor for adaptation, 

recognize the changing climate and seek ways in natural resource 

management to adapt to those changes. Speakers gave examples where 

a United States institution may focus on the conservation of a species 

that, under a changing climate, may no longer find habitat in the lower 

48 states. Does the United States institution broaden to North American 

objectives and focus on the species in Canada? In discussing preservation, 

the question was raised as to what can really be preserved? Many 

participants in the workshop responded that preservation may not be a 

solution under a changing climate. The last metaphor referred to an event 

or issue that disrupts the chickens in the barnyard, tossing the chickens in 

the air. This scattering of the barnyard would force a total reconsideration 

of options such as current discussions about changing from a fossil fuel 

economy raises reconsideration of nuclear power. The question of how 

to face changes in institutional and organizational objectives were seen as 

Figure 4—Downward spiral of rangeland ecological integrity from invasive species, wildfire, climate 

change and other human disturbances (from Pellant’s presentation at the Conference).

?

Invasive

Species Wildfires

Natives

Natives &

 Cheatgrass

Cheatgrass

Perennial Invasive

 Forbs

Will downward spiral of rangeland ecological 

integrity be accelerated?

Human

Disturbances

Climate

Changes

Many participants in the 

workshop responded that 

preservation may not be a 

solution under a changing 

climate. 
101

even more critical for organizations and institutions that focus on more 

local landscapes than regional or national groups. 

Institutions or owners tied to a particular landscape face other 

management problems. Kyle Martin discussed climate data needs on tribal 

lands and the different risks associated with different tribal lands under 

a changing climate. The West is a mix of multiple ownerships and land 

managers each with unique management objectives and perceptions of 

risk. These differing resource management goals challenge management of 

vegetation and hydrological changes across ownerships. 

The broad scale nature of climate change and how human perception 

of and response to it varies complicates governance efforts. For example, 

discussions of how to manage potential changes to river flow from climate 

change will eventually involve managers of various ecosystem components 

such as fish, rivers, land use, and will raise questions about who has the 

authority to make management decisions. In addition there already is a 

mix of market and regulatory functions that have evolved to guide land 

management activities. These include very formal processes for federal 

forestlands that involve stakeholder participation and few apparent 

processes for privately owned forestland other than for being compliant 

with state forest practice acts that influence the design and applications 

of forest management practices. All of this raises questions about the 

necessity of policy intervention, how to accomplish it, and the form it 

needs to take to address climate change.

Institutional and Individual Perceptions 

of Adaptation, Mitigation, and Risk

The conference included managers and land owners who manage 

for a diversity of objectives from relatively intensive to custodial. The 

land managers represented a variety of institutions and organizations, 

some where only a few individuals are involved in decision-making 

to institutions where planning is a public process. Since public lands 

dominate much of the western landscape, management activities are in 

the public eye and changing objectives and management on public lands 

to respond to a changing climate involves the acceptance of the relevant 

publics.

Discussions revealed differences in various perceptions of the threat of 

a changing climate, proposed management responses, associated costs, and 

the calculation of risks associated with potential threats of climate change. 

Public and institutional perceptions of environmental change influence 

efforts to deal with that change. There is public skepticism of the science 

associated with climate change—many individuals in the public want to 

see environmental changes before deciding how to act. Part of the issue 

is that managers and scientists communicate risks in terms of threats to 

safety and property but many in the public react to broader threats such as 

impacts on community or ecological well-being. Another way to consider 

this is that many people do not put climate into their problem framing. 

Since public lands dominate 

much of the western 

landscape, management 

activities are in the public 

eye...

There is public skepticism 

of the science associated 

with climate change—many 

individuals in the public 

want to see environmental 

changes before deciding how 

to act. 
102

Courtney Flint described one situation (the Spruce Bark Beetle 

outbreak on the Kenai Peninsula, Alaska) where the public does perceive 

the link between changing climate and the loss of local forests to increased 

disturbances. There the threat of changing climate has manifested itself in 

large scale forest die-off and management responses are now being framed 

that consider climate.

Several aspects of the discussion suggested that managers are starting 

to reframe their management problems to include climate. Currently 

much of this reframing is reactive but more proactive approaches are 

possible as forest or range managers include climate in their management 

frameworks. For example, forest managers could do this by developing 

yield functions that are sensitive to climate. 

Jim Stevens described the active management regimes characteristic 

of a timber investment organization where the challenges and risks to 

the timber inventory were constantly being recalibrated in order for 

the company to take action to maintain their investment. Companies 

approach risk by diversification of their portfolios, and through 

geographic diversification and species mix. He described potential climate 

change impacts to forestry and their related costs—higher extreme 

events such as fire danger and the higher costs of fire monitoring and 

suppression, insect damage, drought, invasive species, shorter dormancy 

and potential increases in reforestation problems, shorter dormancy. 

These approaches do not yet incorporate climate variables—precipitation, 

temperature, soil water—so managers are unable to estimate the impact of 

climate change on net returns to forest management investments. 

Institutions and organizations may also have to address new 

policy and management objectives, such as fuels management, carbon 

sequestration, and biomass energy. These represent a possible suite of 

changing or additional objectives for natural resource management in 

the Western United States. Darius Adams described forest management 

activities that could increase the carbon storage in forests (fig. 5). Matt 

Delaney described the international and national policies with respect 

to carbon sequestration and the carbon accounting activities, such as 

carbon sequestration in forests. Most of this activity has been in the East 

or Midwest. Overwhelmingly there was a lack of knowledge among the 

participants about how energy policy and climate change policy were 

moving, particularly in terms of carbon sequestration, what role forests 

might play and what the benefits might be to land owners. Bill Carlson 

described the biomass energy arena, the current challenges to developing 

biomass energy as well as the current possibilities. In the course of 

managing forests and rangelands, Bill Carlson noted that managers 

can contribute to the reduction in greenhouse gas generation by the 

management methods chosen. Biomass growth, utilization and disposal 

is theoretically greenhouse gas neutral, but some disposal methods 

generate large quantities of methane and other hydrocarbons, upsetting 

the balance and increasing global warming potential. For biomass power, 

Bill described the outlook is best in 15 years, as fossil fuel prices are 

increasing, renewables (solar, wind) in favor (19 states with renewable 

portfolio standards), tax credits are being enacted, and forest fuel subsidies 

Overwhelmingly there was 

a lack of knowledge among 

the participants about how 

energy policy and climate 

change policy were moving, 

particularly in terms of 

carbon sequestration, what 

role forests might play and 

what the benefits might be 

to land owners.
103

are being considered in energy policy. Land managers have tools to lower 

greenhouse gas emissions in forest management activities while preserving 

carbon inventory and preparing the land for an increased rate of carbon 

sequestration, but Bill cautioned that managers must be aware of the 

methods and conditions that will allow them to attract the infrastructure 

necessary to accomplish this management objective.

Regulations that companies deal with may change, such as climate 

warming the stream temperatures and then regulations in forestry 

changing to deal with this management issue for fisheries. Most land 

managers are concerned about the regulatory risks from climate change 

effects. 

In the presentations and in the discussion period, it was clear that 

the terms participants used had different definitions depending upon the 

context in which they operated—disciplines, careers, and perspectives. 

Common definitions may not be possible, so it is very important to state 

the context out of which a person comes. Adaptation, mitigation, and 

restoration were some terms that had different definitions depending 

upon if the proponent was an ecologist or a social scientist. Short 

versus long terms was also in the observer’s eye. Risks and uncertainty 

were commonly misunderstood across a diverse set of participants. For 

example, Benjamin Harding offered a clarification of the definition of 

variability—the effect of change, and uncertainty—imperfections in the 

state of our knowledge. He suggested that there are two components to 

uncertainty: measurement error and what we don’t actually know (such as 

being surprised by something that was not considered). 

Figure 5—Activities to increase carbon storage in forests (from Adams Presentation at the Conference)

— Options for Raising Net Forest Carbon Flux —

n Regulating Forest Area

q Afforestation Of Agricultural Lands

l Major Source Of Large, Long-Term Increments

l Restricted Time Pattern Of Flux Changes

l Difficulties Tracing Carbon In Use Changes

q Reducing Forest Land Losses To Other Uses

l Large Potential

l Can Have Immediate Impact—Carbon Losses 

Averted

n Altering Management In Currently Forested Areas

q Existing Stands (Rotation Age, Intermediate Practices)

q New Stands (Regeneration Practices, Intermediate 

 Treatments And Rotation

q Can Provide Large, Near-Term Carbon Increments

q Analytical Problems

l Establishing A Credible Baseline

l Simulating Policy Instruments

Most land managers are 

concerned about the 

regulatory risks from climate 

change effects. 
104

Finally, there is confusion about who in the West is in charge of 

broad scale environmental issues. While there is general agreement 

that individual actions contribute to environmental issues globally and 

locally, there are diverse viewpoints about how to govern cross boundary 

problems. Benjamin Harding offered that climate change issues might be 

addressed through the wisdom of crowds where a diversity of opinions 

from individuals who are independent from one and other could be 

aggregated efficiently to develop a management or policy solution. There 

was agreement that there are many solutions to addressing climate change 

in natural resource management and that encouraging a diversity of 

responses is very important for ecological as well as economic resilience. 

Participant Reflections About Resource 

Management Under a Changing Climate

The question for managers is how to plan strategies today for the 

world of tomorrow. Participants suggested a number of concepts for 

future management of natural resources under a changing climate. 

Recognize a Changing Relationship 

Between Climate and Ecosystems

Management must look forward to an uncertain context, rather than 

backward to a presumed certain historical potential natural vegetation. 

Much effort has gone into determining the range of natural variability 

in western ecosystems. This effort has given a detailed picture of the 

past relationship of climate and ecosystems, how ecosystems respond to 

the variability in climate and other natural disturbances. It is not clear 

how well past climate will adequately predict future climate. If climate 

is changing, then the past relationship between climate and ecosystems 

will change. Ecosystems, plants and animals have adapted to these local 

climates and will respond to changes in climate.

Ron Neilson identified the need to improve resilience of ecosystems 

to rapid climate change. Future climates may be drier either through 

increased temperature and/or reduced precipitation. Given this possible 

change, his recommendation is to keep forest stand biomass below the 

water-limiting capacity, so that the stress is lessened. Looking at the 

water limiting capacity of a forest would be recognition of the changing 

relationship between climate and forests. 

Manage Ecosystems as Dynamic 

Systems Not as Static Systems

Management must develop the ability to deal with variation; work 

with the dynamics in natural systems rather than managing the systems 

as static. In contrast, intensive management is a case where managers 

are trying to take advantage of existing dynamics. In many recent 

management approaches especially on public lands there is the assumption 

that extensive or custodial management of natural resources will help the 

ecosystem to restore itself. This works when the processes for resilience 

have not been disrupted, as potentially under a changing climate. In 

...there are many solutions 

to addressing climate 

change in natural resource 

management and ... 

encouraging a diversity of 

responses is very important 

for ecological as well as 

economic resilience. 
105

addition, Gordon Reeves pointed out that some systems like aquatics 

require periodic disturbance to maintain resilience. 

Manage Ecosystems with Agility

Pete Holmberg stressed hedging and not over-reacting. Forests 

should be managed with an agility—making modest changes that do 

not limit management in the future—that recognizes various possible 

contingencies. Although Pacific Northwest forests have life spans 

indicating genetic resilience to historic climate change, forest health may 

still suffer through insect, diseases and fire. Proactive management and 

mixed stands is a prudent approach. He described forest health insurance 

as diversity plus agility plus vigor. 

Bring Climate into the Planning 

and Management Processes

Climate change potentially has implications to many forest and 

rangeland uses: livestock grazing, water quantity and quality, recreation, 

hunting, social and economic uses. It also has implications to the 

success of any restoration treatment—will the result be as we expect or 

another vegetation type developing? Mike Pellant recommended these 

changes to land planning: (1) Incorporate climate change into long-term 

planning, (2) Emphasize flexibility in plan alternatives until science is 

more definitive and (3) Adaptive management. Research and monitoring 

western rangelands is important, as is education and outreach, to make 

the public aware of these potential changes in western rangelands.

Gary Lettman described the Oregon Department of Forestry focus 

on sustainability management and a policy of enhancing carbon storage 

in Oregon’s forests. The 2010 Assessment of Oregon’s forest included the 

consideration of climate change in the landscape analyses. 

But several speakers emphasized that the real challenge was to get 

the science to the local planning level. How, they ask, can local managers 

respond to perspective changes without some indication of how the 

resources they manage be impacted?

Information Needs of Managers

Speakers and small group discussions suggested a number of 

information needs for resource managers in the Western United States. 

The information needs that evolved from the Roundtable Discussions 

are described in more detail (White and Barbour, this report). How 

these information needs were to be solved was not discussed. Recent 

observations of western natural resource management would suggest that 

resource agencies are pushing ahead to get this information internally or 

engaging researchers to work with them to obtain the needed information.

Local to subregional climate projections—Current climate 

models observe and project climate at very large simplified spatial scales. 

Nearly all resource managers identified the value and need for such 

information on the local scale. The utility of the large scale models is 

Forests should be managed 

with an agility—making 

modest changes that do not 

limit management in the 

future...

...several speakers 

emphasized that the real 

challenge was to get the 

science to the local planning 

level.
106

particularly problematic for western resource managers where the West is 

topographically variable. 

Hydrologic projections at appropriate scales—Water demand 

analyses utilize climate data. What is needed is the conversion of the 

climate scenario data into a format that can be readily used. Water 

managers in the Pacific Northwest worked with the Climate Impacts 

Group, University of Washington, to obtain such data for their future 

water demand analyses. Such information is needed by water managers in 

other parts of the western United States.

More local or locally adaptable models for forestry—Plants and 

animals adapt to the local climate. Models that reflected local conditions 

would enhance forest managers’ ability to respond to these changes.

Vulnerability indices for ecosystems and for ecosystem 

components—An assessment of how vulnerable western ecosystems are to 

climate change would assist managers in prioritizing funds and tasks. 

Monitoring protocols—What to monitor with respect to climate 

change was a question raised by resource managers. Identifying what to 

monitor and having a protocol to monitor would assist land managers 

in observing changes and developing management strategies for those 

changes. Participants also described the needs for both success and early 

warning indicators.

Clearing house for information at the regional scale—It was 

recognized by the conference participants that there is a wealth of 

information on climate and climate change impacts. A clearinghouse 

that would organize not just data on climate, and ecosystems, but also 

assessment studies and models was identified as an important need.

Conclusions

The presentations and discussions at the workshop illustrated the 

complexity of global climate change and they emphasized that the impacts 

of climate change will unfold on the regional and local stages. We were 

reminded repeatedly that little concerted action would take place until 

the issue could be described in relation to specific localities relevant to 

land managers. The discussions also revealed the wide spectrum of threat 

perceptions. There were scientists and managers who believed in the 

inevitability of climate change, there were managers who were willing to 

consider hedging future projections accepting climate change as one of 

many risks, and there were many who needed to perceive changes before 

forming perceptions about the threat. Finally, the broad scale nature of 

climate change complicates both the human perception of and response 

to it. One consequence of this is to consider how we govern forested 

ecosystems when forest management takes place across relatively large 

geographic spaces composed of many different landowners with a myriad 

of land management objectives. While no simple solutions emerged, 

there was an appreciation that policy complexity may exceed the science 

complexity. 

Models that reflected local 

conditions would enhance 

forest managers’ ability to 

respond to these changes.

We were reminded 

repeatedly that little 

concerted action would take 

place until the issue could 

be described in relation to 

specific localities relevant to 

land managers. 
107

Finally, the workshop offered a glance of hope in that managers are 

already responding to those aspects of the global climate change that they 

can see or perceive. Eventually the accumulation of these local actions 

will shape our future. In this sense the workshop achieved its purpose 

in furthering the dialogue among early adopters of how individuals are 

addressing climate change in natural resource management. Through civic 

engagement, we can help reduce the complexity of the issue and increase 

the certainty of outcomes in the face of changing climate.

References

Haynes, R.W., tech. coord. 2003. An analysis of the timber situation in the United 

States: 1952 to 2050. Gen. Tech. Rep. PNW-GTR-560. Portland, OR: U.S. 

Department of Agriculture, Forest Service, Pacific Northwest Research Station. 

254 p.

Haynes, R.W.; Adams, D.M.; Alig, R.J.; Ince, P.J.; Mills, J.R.; Zhou, X. [In 

prep.]. The 2005 RPA timber assessment update. Gen. Tech. Rep. PNW-GTRxxx. On file with: Richard Haynes, Portland Forestry Sciences Laboratory, P.O. 

Box 3890, Portland, OR 97208.

Haynes, R.W.; Adams, D.M.; Mills, J.R. 1995. The 1993 RPA timber assessment 

update. Gen. Tech. Rep. RM-GTR-259. Fort Collins, CO: U.S. Department 

of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment 

Station. 66 p. 

Joyce, L.A.; Mills, J.R.; Heath, L.S.; McGuire, A.D.; Haynes, R.W.; Birdsey, R.A. 

1995. Forest sector impacts from changes in forest productivity under climate 

change. Journal of Biogeography. 22: 703-713.

Trenberth, K.E.; Houghton, J.T.; Filho, L.G. Meira. 1996. The climate system: 

an overview, Chapter 1. In: Houghton, J.T., Filho, L.G. Meira, Callander, B.A., 

Harris, N., Kattenberg, A., Maskell, K., eds. Climate Change 1995. Cambridge, 

England: Cambridge University Press: 51-64. 

Wilkinson, C.F. 1992. Crossing the next meridian. Land, water, and the future of 

the West. Washington, DC: Island Press. 376 p.

Ziska, L.H. 2003. Evaluation of the growth response of six invasive species to past, 

present and future carbon dioxide concentrations. Journal of Experimental Botany 

54:395-404.

...managers are already 

responding to those aspects 

of the global climate change 

that they can see or perceive. 

Eventually the accumulation 

of these local actions will 

shape our future.
108
109

1Science Writer-Editor, USDA Forest Service, Pacific Northwest Research Station, P.O. Box 3890, Portland, OR 97208. Email: rachelwhite@fs.fed.us

2Program Manager, USDA Forest Service, Pacific Northwest Research Station, P.O. Box 3890, Portland, OR 97208. Email: jbarbour01@fs.fed.us

Rachel White1 and Jamie Barbour 2

The Roundtable Session

USDA Forest Service
110

As Albert Einstein observed “You cannot solve current problems with 

current thinking. Current problems are the result of current thinking.” In 

recognition of this, we wanted to try a more innovative way of presenting 

information. Most conferences are a combination of entertainment and 

education—they must promise topics interesting enough to pull people 

away from busy schedules, and they at least hold out the pretext of 

providing new information to the audience. But however you characterize 

most conferences, the audience is always a passive receptor. The Focused 

Science Delivery program is attempting to give the audience a voice; 

because although it is true that the presenters are considered the experts, 

we contend that the collective knowledge of the audience is probably as 

great as or greater than that of the presenters when the topic as a whole 

is considered. The “Bringing Climate Change into Natural Resource 

Management” conference was attended by 113 individuals representing 

20 organizations, including government agencies, tribal organizations, 

conservation groups, and the timber industry. One of the goals of this 

workshop was to allow these practitioners to offer their ideas on the 

pressing problems they face in attempting to adapt management plans and 

policies in the face of a changing climate. 

To this end, we set up a roundtable session, which got participants 

out of passive listening mode and into active brainstorming together. 

The roundtables were intended as the initial step in a problem framing 

process. This refers to the fact that different stakeholders have their own 

perspectives, interests, and priorities. The way an issue is “framed” reveals 

differences in the way stakeholders form interpretations of what is at stake 

and what approach should be taken. The importance of problem framing 

is being recognized in a small but growing literature (Bardwell 1991, 

Miller 1999, Stankey et al. 2005, Van Cleve et al. 2003).

We took 10 different topics relevant to current natural resource 

management—water, fisheries, silviculture, invasives, wildlife, 

preservation, management and policies for adaptation of western 

ecosystems, carbon policy, mitigation of human impacts, and science 

consistency—and assigned each topic to a table. Participants then selected 

their topic area of interest, and were given an hour to discuss their table’s 

topic in light of the three following questions: 

1. What information do you need in a natural resource management 

plan to address climate change? 

2. What do you currently have that you could use to address the 

information needs identified in question 1?

3. What are the top 2 or 3 critical information needs and/or tools that 

you currently don’t have that would help you make better decisions 

with respect to this management issue and adapting to climate 

change and variability?

Each group recorded major themes and ideas on a flip chart. Prior 

to the meeting the organizing committee had identified a leader for each 

table who was assigned the task of keeping the discussion focused on 

climate change. Each group also chose a “spokesperson,” who reported 

back to the audience at large the main points discussed by their table. 

...although it is true that the 

presenters are considered the 

experts, we contend that the 

collective knowledge of the 

audience is probably as great 

as or greater than that of the 

presenters when the topic as 

a whole is considered. 
111

The purpose of the reports was twofold. First, to concisely summarize 

what was said, and second, to stimulate further conversation over the rest 

of the conference among the group members and others who did not 

participate in that particular group. Accordingly, each reporter was given 

two opportunities to report their findings. The first came at the end of the 

day the roundtable sessions were held. Each reporter was given 5 minutes 

to present the major points from the discussion, members of that group 

were given an opportunity to add missing information, and the general 

audience was encouraged to ask clarifying questions.

At the end of that day’s session the audience was reminded to talk 

among themselves about what they had discussed at their respective tables 

and what they had heard during the initial set of summary reports. The 

second opportunity for reports came at the end of the conference when 

table reporters were asked to present a synthesis of the most important 

points of their roundtable discussions, the conversations they had after the 

first reporting, and any other related interactions with other conference 

participants. They were reminded that the intent of the exercise was to 

present the views of the audience not necessarily their own views.

We also included a note-taker at each table during the discussions. 

This person was instructed to be as unobtrusive as possible and to record 

the conversation as accurately as possible. The note-taker was allowed to 

ask clarifying questions but not to take part in the conversation itself. The 

note-taker’s goal was to record what was said but not necessarily by whom.

Together these techniques provided three sources of information in 

addition to our own observations. They were: flip chart notes from each 

table, note-taker notes from the roundtable discussions, and notes from 

the table leader presentations. We compiled those bits of information into 

the narrative that follows.

The 10 tables covered topics big and small—from seed sources to 

public awareness to landscape connectivity—as participants confronted 

the uncertainties and challenges surrounding climate change. But around 

the room common topics began to emerge. The major themes we will 

emphasize in this narrative were distilled from these common threads, as 

we could not include all the ideas and issues brought up at all 10 tables. 

Better information and better access

Participants identified a wealth of information that is currently 

available, such as the climate and ecological published literature, results 

from global studies, and results from ecological models. However, 

participants frequently mentioned the need for improved access to 

information and studies, in progress or completed. They said they find 

information to be scattered, or displayed as stand-alone scientific facts 

that are never translated into management implications. Because of 

this, knowing what’s known and what might be useful is a problem. For 

example, there have been some regional risk assessments that address large 

scale changes in forest response to carbon and climate already. But it is 

unclear whether this information is finding its way into use, and some 

managers at the roundtable session mentioned it would be more useful if 

it could be made available at smaller scales.

participants...said they find 

information to be scattered, 

or displayed as stand-alone 

scientific facts that are never 

translated into management 

implications. 
112

Another area where participants need better access to information 

involves carbon sequestration, which has significant implications for forest 

management. In fact, there is growing recognition that land management 

strategies that aim at increasing the volume of carbon storage in forests 

could make a considerable impact on global CO2 concentrations 

(Peterson et al. 2004). But managing for carbon storage can have complex 

and potentially unintended consequences. As one participant noted, 

sequestering carbon by letting trees grow generates fire hazard. Society 

has only relatively recently begun to recognize the impact on forest health 

and fire risk that a century of aggressive fire suppression has had, and 

that many fire-adapted forests need to be thinned or burned regularly. 

For forest managers, the tradeoffs between fuel treatments and carbon 

sequestration might become a serious management consideration.

Other information requests focused on expanding current 

understanding of natural resource dynamics and ecological systems 

by looking at the influence of climate variability on these systems. 

For example, information requests included identifying and mapping 

“sleeper” invasive species (ones that aren’t a problem now but that might 

experience increased vigor and expansion with climate change variations); 

information on climate change impacts on growth and yield; and a 

synthesis of literature on ecosystem resilience under climate change. “We 

need to get at how to make communities as resilient as possible [given 

expected climate variation],” said one participant. “How do we build 

pools of biodiversity? How do you create a landscape with corridors and 

refugia that allows movement but so you don’t lose the specialists?” 

Data, models, projections

Climate change involves such unstable systems on such a grand 

scale that there is no way to conduct experiments on how the global 

climate changes. Because of this, climate science relies heavily on large 

sets of historical records of climate and other environmental data, and on 

computer models and simulations. Participants recognized the value of 

long-term records of temperature and precipitation and also the need for 

better access to these records. They also identified the need for long-term 

data on climate-related factors such as hydrological data and snow pack 

data, particularly for local conditions. Often a finer time scale is needed 

by managers, such as daily records. Sometimes this information exists, but 

inconsistently. For example, there are approximately 2,200 interagency 

Remote Automated Weather Stations across the U.S. that collect weather 

data. They provide a useful source of information, but because they are 

currently used mainly by the fire-fighting community, they don’t operate 

in the winter. Year-round data collection at would make this information 

source even more valuable to managers.

 Participants also recognized the need for reasonable projections 

and usable computer models in their work. For example, they want to 

know how precipitation will change in the next 50-100 years. Scientific 

projections showing increases in temperature are fairly robust, but there is 

greater variability in the precipitation projections. Participants identified 

a need for this projection information, especially at a scale relevant to 

management plans or models currently in use. 

“How do we build pools 

of biodiversity? How do 

you create a landscape with 

corridors and refugia that 

allows movement but so you 

don’t lose the specialists?” 
113

Participants would also like localized projections of climate change 

impact on plant associations, insects, disease, fire risk, and adaptive plant 

movement zones; a better description of the interactions between climate 

change and other threats such as land use changes and human population 

changes; accurate species-based habitat models that could be used to 

monitor changes over time; and vulnerability maps that identify species 

most sensitive to climate change. There are models managers currently use 

that need to have climate added as a component, such as the growth and 

yield models used in silviculture, and in hydrological forecasting models. 

In general, better modeling of potential threats is crucial to constructing 

climate change response strategies in management plans. In the face of 

so much uncertainty, and without some precautionary help from models 

and projections, it is extremely difficult to balance the risks of either 

insufficient or excessive action. 

Monitoring

Species have evolved adaptive mechanisms that allow them to adjust 

to, or at least tolerate, short-term fluctuations without serious damage. 

For example, many plants and animals can accommodate a week of record 

temperatures, or a few months of drought. But these adjustments create 

small impacts that accumulate over time, and in the face of longer or more 

extreme disturbances, the elasticity of these systems begins to wear thin 

(Pollack 2003). At a certain threshold, systems that had been adapting 

will begin to break down. Without monitoring this progression, it will be 

impossible to anticipate these thresholds and do anything to intervene. 

Participants grappled at length with this issue, and came up with several 

information gaps and questions. 

For example, rather than trying to protect a single species, how do you 

protect the landscapes that can serve as habitat for multiple species? How 

do you then measure this? “We need a monitoring strategy of physical 

systems at a scale that matters,” said one person. “It must be cheap and 

easy to measure, and it must be tailored to the resource.” It must also be 

conducted with climate change in mind. One thing to remember is that 

climate change will certainly change habitat conditions, which may allow 

for migration or dispersal of some species, reduce the range of others, and 

create new interactions between native species and invasives. Given this 

potential for movement and habitat loss, it would probably be a good idea 

to monitor genetic heterogeneity of populations over time to measure 

whether they are becoming more genetically isolated and homogeneous. 

There is also a need to continue tracking changes in diseases, pathogens, 

and insects and their impacts. Finally, climate change will involve an 

increased need to monitor water supply, water storage, and soil moisture, 

because projections forecast changes in average precipitation in many 

regions.

Negotiating regulations

The ability to manage forests under future climate regimes rests 

heavily on a better understanding of the processes at work, and on better 

access to good scientific information. But it also rests on the policies 

In the face of so much 

uncertainty, and without 

some precautionary 

help from models and 

projections, it is extremely 

difficult to balance the risks 

of either insufficient or 

excessive action. 

...climate change will 

involve an increased need to 

monitor water supply, water 

storage, and soil moisture, 

because projections 

forecast changes in average 

precipitation in many 

regions.
114

and regulations that guide (and sometimes restrict) natural resource 

management planning. Regulations such as the Endangered Species Act 

(ESA), and the National Environmental Policy Act (NEPA), were founded 

on the assumption of static vegetative composition and don’t incorporate 

flexibility. As a result, active management tends to be reactive as opposed 

to agile and adaptable. How can the ESA protect species under climate 

change if it doesn’t include awareness of habitat changes?

Discussion at the roundtable session often led back to the need for 

a good sense of tactical options and solutions available under current 

policy structures. In other words, given the range of genetic variation in 

forest stands, and given what’s likely to happen as climate changes, what 

silvicultural options are open to us? What treatment alternatives based 

on rotation length, rate of carbon storage and carbon expenditure are 

available? A potential approach would be to provide an array of options 

for forest managers and policy makers to consider, and to inspire more 

flexibility. 

In addition, we heard from participants that it would be helpful to 

have some idea of how states differ in their energy policies and politics, 

and what direction energy policy may be headed in. For instance, with 

the current increase in gas prices will we still be using as much gasoline 

in the future? Will we rely more on wood to provide energy? Looking at 

energy, woody biofuel, carbon sequestration, and fire risk together could 

aid managers in formulating the multiple strategies that might go into 

a management plan that incorporates climate change. Another concern 

participants mentioned is the need for economically viable opportunities 

to deal with climate change, such as harvesting small diameter timber. 

Is there an accessible infrastructure (rails to move product)? There have 

been several studies exploring the relationships between timber markets 

and climate change, in fact there is a large amount of information 

available on carbon, climate change, and forests, but it is rarely addressed 

in management plans. Some of our participants admitted knowing that 

information exists, but find it difficult to keep up with it or even locate it. 

This suggests that assisting practitioners in finding information when they 

need it could be valuable.

Many managers acknowledged that the challenges of coping with 

climate change go beyond better information and better access to it. 

Actions are often constrained by current policies and local management 

practices. And it’s difficult to motivate change in natural resource 

management based on potential future changes when there are many 

pressing issues facing managers already, such as fire risk, insect outbreaks, 

and increasing demand for water supply in the West. Still, even though it 

may be challenging to address climate change at a local project level, that’s 

where many decisions are made, and all our participants agreed that the 

potential impacts of climate change on natural resources will need to be 

addressed at the local level. This task will involve viewing ecosystems as 

dynamic systems, synthesizing information across land ownerships, and 

evaluating risk based on climate change impacts and other disturbances. 

Discussion at the roundtable 

session often led back to 

the need for a good sense 

of tactical options and 

solutions available under 

current policy structures.

...participants agreed that 

the potential impacts of 

climate change on natural 

resources will need to be 

addressed at the local level.
115

Summary

The deliberations of our roundtable participants formed a clearer 

idea of the management implications and information needs associated 

with climate change. After distilling the many comments and questions 

we heard at the roundtable sessions, we’ve summarized some of general 

recommendations we heard from participants for successful integration of 

science and management in coping with this issue. 

Looking back

To put climate change into perspective, we need an understanding 

of historical context. Tracking historical data on how different vegetation 

has responded to variations in temperature and precipitation can 

provide insight into how we might anticipate future change. Similarly, 

understanding how different systems have responded to past disturbances 

provide clues as to what makes a system resilient. 

Looking ahead

We need to continually improve the tools we have that can show 

what’s going on and what’s most likely to happen. We also need to make 

sure these tools are available and accessible. Computer models and 

projections may include a lot of uncertainty but can still help in guiding 

decisions. We might think of heading into the future as akin to driving at 

night: our computer models act as headlights, dimly illuminating the road 

ahead, and we may not be able to see much, but maybe we can at least 

stay on the right road. The more accurate and accessible our modeling 

tools are, the better able we are to maintain flexibility and adapt our 

management objectives as the future unfolds.

Collaboration

A common concern among our participants was the disconnection 

between research and management, and between various agencies and 

organizations. Many agencies manage as if they were islands and get 

overwhelmed when trying to view the uncertain path ahead from the 

vantage point of their resources, time, and energy alone. The task may 

become easier if we can join forces, work across agency boundaries, and 

pool information and resources. This would help in terms of consistency 

of data and better ability to identify trends, but also would enable groups 

to learn from each other’s mistakes and triumphs. “We need a peer group 

so we can interact and share hypotheses and success stories,” said one 

participant. “Are there any examples out there? Are there management 

plans out there that incorporate climate change that we can work from?”

Communication

There is no longer much scientific debate as to whether climate 

change is happening. But confusion about the potential consequences and 

what we should do to counteract or accommodate these consequences, 

along with an inability to fully grasp a phenomenon that operates on an 

entire planet on a time scale that exceeds life spans and even generations, 

Many agencies manage as 

if they were islands and get 

overwhelmed when trying 

to view the uncertain path 

ahead from the vantage 

point of their resources, 

time, and energy alone. 
116

creates an aura of disbelief, hesitation, and doubt. To get the attention and 

support of a public immobilized by the uncertainties of climate change, 

managers need an interpretive tool, such as graphically displayed, distilled 

information. Scientists can respond by making this information easier for 

the public to understand and easier for managers to make use of. 

Meanwhile, new international climate data indicates that 2005 is 

shaping up to be the hottest year on record, with 2002, 2003, and 2004 

not far behind on the list. And sea surface temperatures in the Gulf of 

Mexico were higher in August of this year than at any time since 1890, 

which may have contributed to the intensity of the hurricane season 

there. And while we still can’t attribute any single weather event to 

climate change, we can recognize that extreme weather events have been 

increasing in the past few decades. There is no reason to believe that 

climate change will disappear, and it may even become more difficult 

for natural resource managers to deal with in the future, especially if 

policy and implementation continue to lag behind scientific discovery. 

But identifying information gaps is crucial, and it is our hope that these 

roundtable discussions will result in an increased focus on the role of 

management in addressing climate change, and will improve the delivery 

of good science to the practitioners who need it. During our discussions 

there was a realistic and sobering acknowledgement of the uncertainties 

that lie ahead, and that there is often a tendency to succumb to hesitance 

or irresolution in the face of this confusion. But confusion is the 

beginning of knowledge, and we hope that we can turn information gaps 

into an opportunity, and use uncertainty as a stimulus for creativity.

References

Bardwell, L.V. 1991. Problem-framing: a perspective on environmental problemsolving. Environmental Management 15(5): 603-612.

Endangered Species Act of 1973 [ESA]; U.S.C. 16: 531-1536, 1538-1540.

Miller, A. 1999. Environmental problem solving: psychological barriers to adaptive 

change. New York: Springer-Verlag. 239 p.

National Environmental Policy Act of 1969 [NEPA]; 42 U.S.C. 4321 et seq.

Peterson, D.L.; Innes, J.L.; O’Brian, K. 2004. Climate change, carbon, and 

forestry in northwestern North America: Proceedings of a workshop. November 

14-15, 2001, Orcas Island, Washington. Gen. Tech. Rep. PNW-GTR-614. U.S. 

Department of Agriculture, Forest Service, Pacific Northwest Research Station: 

Portland, OR. 

Pollack, H. 2003. Uncertain science, Uncertain world. Cambridge,UK: Cambridge 

University Press. 243 p.

Stankey, G.H.; Clark, R.N.; Bormann, B.T. 2005. Adaptive management of natural 

resources: theory, concepts, and management institutions. Gen. Tech. Rep. PNWGTR-654. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific 

Northwest Research Station. 73 p.

Van Cleve, F.B.; Simenstad, C.; Goetz, F.; Mumford, T. 2003. Application of 

“best available science” in ecosystem restoration: lessons learned from large-scale 

restoration efforts in the U.S. Puget Sound Nearshore Ecosystem Restoration 

Project. 38 p. http://www.pugetsoundnearshore.org.

There is no reason to believe 

that climate change will 

disappear, and it may even 

become more difficult for 

natural resource managers 

to deal with in the future, 

especially if policy and 

implementation continue 

to lag behind scientific 

discovery. 
117

The Potential for Widespread, Threshold Dieback of 

Forests in North America Under Rapid Global Warming 

R.P. Neilson1, J.M. Lenihan1, D. Bachelet 2, R.J. Drapek1, D. Price3, D. Scott 4

1Bioclimatologist, Ecosystem Modeler, Ecosystem Modeler/GIS Technician USDA Forest Service, PNW Research Station, 3200 S.W. Jefferson Way, Corvallis, OR 

97331; Email: rneilson@fs.fed.us; jlenihan@fs.fed.us; rdrapek@fs.fed.us

2Associate Professor, Department of BioEngineering, Oregon State University, Corvallis, OR 97331; Email: bachelet@fsl.orst.edu

3Research Scientist, Integrative Climate Change Impacts Modelling, Canadian Forest Service, Northern Forestry Centre, 5320 - 122 Street, Edmonton, AB, T6H 

3S5; Email: dprice@nrcan.gc.ca

4Canada Research Chair in Global Change and Tourism, Department of Geography, University of Waterloo, Waterloo, ON, N2L 3G1; Email: dj2scott@fes.

uwaterloo.ca

— Extended Abstracts —

Erik Ackerson, EarthDesign, Ink
118

Abstract

The MC1 Dynamic General Vegetation Model (DGVM) was used 

to assess the impacts of global warming on North American ecosystems, 

north of Mexico, under six future climate scenarios (three General 

Circulation Models X two emission scenarios). The simulations were 

begun in 1900 using observed climate and CO2 until 2000, then 

transferring to the future scenarios to 2100. Carbon sequestration over 

the continent occurred in the late 20th century and for a short period 

into the 21st century, being fostered largely by increased precipitation, 

enhanced water-use efficiency and mild temperature increases. However, 

these ‘greening’ processes were overtaken by the exponential effects 

of increasing temperature on evaporative demand and respiration, 

producing a subsequent decline. Simulation experiments suggested that 

fire suppression could significantly mitigate the carbon losses, yet many 

ecosystems were still forced to a lower carrying capacity.

Keywords: Global warming, carbon balances, ecosystem dynamics.

Discussion

An assessment of North American carbon balance and ecosystem 

dynamics, including changing vegetation distribution and fire 

disturbance, in ‘natural’ ecosystems has been undertaken. The VINCERA 

project (Vulnerability and Impacts of North American forests to Climate: 

Ecosystem Responses and Adaptation) is an intercomparison among 

three dynamic general vegetation models (DGVMs) running under 

six new future climate scenarios. The scenarios were produced by three 

general circulation models (GCMs), each using two different future 

trace gas emissions scenarios, SRES A2 and B2. The GCM scenarios 

are from the Canadian Climate Centre (CGCM2), the Hadley Centre 

(HADCM3) and Australia (CSIRO-MK2). The three DGVMs are 

MC1, IBIS and SDGVM. All of the scenarios are near the warmer end 

of the Intergovernmental Panel on Climate Change’s projected future 

temperature range. 

We present here only the results from MC1 (Daly et al. 2000). With 

the exception of the tundra, which is invaded by the boreal forest, all 

major forested ecosystems in North America exhibit carbon sequestration 

until the late 20th or early 21st century, followed by a drought-induced 

decline and loss of carbon to levels below those at 1900 in the absence 

of fire suppression (fig. 1). By the end of the 21st century in the absence 

of fire suppression, the entire continent will have lost from 10 to 30 Pg 

of carbon, depending on the scenario. However, fire suppression can 

significantly mitigate carbon losses and ecosystem declines, producing a 

net change in carbon from a loss of about 5 Pg to a gain of about 8 Pg 

under the different scenarios (fig. 2). Most of the suppression benefits are 

obtained in the Western U.S. forests. However, suppression also mitigates 

carbon losses and conversions to savanna or grassland in the Eastern 

United States, but forest decline still occurs in the East under all scenarios.

With the exception of the 

tundra, which is invaded by 

the boreal forest, all major 

forested ecosystems in North 

America exhibit carbon 

sequestration until the late 

20th or early 21st century, 

followed by a droughtinduced decline...
119

North America

(with fire) 

20

10

-10

-20

0

-30

1900 1925 1950 1975 2000 2025 2050 2075 2100

CGCM2A

Ecosystem carbon change (Pg)

-40

CGCM2B HADCM3A HADCM3B CSIROA CSIROB

Figure 1—Net gain or loss of carbon from North American Ecosystems under climate change, without fire 

suppression.

North America

(fire suppression) 

20

10

-10

-20

0

-30

1900 1925 1950 1975 2000 2025 2050 2075 2100

CGCM2A

Ecosystem carbon change (Pg)

-40

CGCM2B HADCM3A HADCM3B CSIROA CSIROB

Figure 2—Net gain or loss of carbon from North American Ecosystems under climate change, with fire 

suppression.

Tom Iraci, USDA Forest Service
120

The MC1 simulations produce a significant dieback in Eastern U.S. 

forests under all scenarios as well as excursions of the central grasslands 

into the boreal forest zone. Dieback is triggered under two mechanisms. 

Reduced regional precipitation patterns, variable among the scenarios, 

are one mechanism for dieback. However, a more insidious and more 

pervasive effect is due to the exponential influence of rising temperatures 

on evapotranspiration (ET). Even with the benefits of enhanced water 

use efficiency from elevated CO2 and slight increases in precipitation, 

dramatic increases in temperature can produce widespread, very rapid 

forest dieback, followed by infestations and fires. The Eastern United 

States appears to be particularly vulnerable to this sequence of processes, 

as does the central boreal forest. The reason for the widespread sensitivity 

of these forests is the relative flatness of the climate gradients. If one 

locale is near a transition from forest to savanna, then so too are large 

neighboring locales.

Under some scenarios, dieback is driven by both increasing 

temperatures and decreasing precipitation in some regions, notably 

the Southeastern United States and the Northwestern United States. 

Following a period of gradual carbon sequestration, the enhanced ET 

appears to overtake the ‘greening’ processes producing a rapid dieback. 

The dieback occurs over North America within a few decades from now, 

initiating an extended period of rapid losses of ecosystem carbon.

Note added in Proof: Recent findings on the strength of the CO2

effect have been incorporated in new simulations in the VINCERA 

project. The conclusions are not qualitatively changed. However, the 

strength of potential sequestration under fire suppression is increased 

in both eastern and western forests (figs. 3, 4). The level of dieback of 

eastern forests is somewhat reduced and can even be reversed with active 

fire suppression or exclusion, in some scenarios. Overall, the continent 

sequesters carbon, even with no fire suppression, with gains being greater 

under the hotter A2 scenarios due to the enhanced CO2 effect (fig. 3, 

average 32 Pg compared to 16 Pg under B2). With active fire suppression 

or exclusion continental carbon sequestration by the end of the 21st

century under the A2 scenarios averaged 63 Pg compared to 36 Pg 

under the B2 scenarios (fig. 4). It must be emphasized that there is still 

uncertainty as to whether the higher or more modest CO2 effect will be 

more realistic in the long run, since the data come from relatively young 

stands.

References

Daly, C.; Bachelet, D.; Lenihan, J.M.; Parton, W.; Neilson, R.P.; Ojima, D. 2000.

Dynamic simulation of tree-grass interactions for global change studies. Ecological 

Applications. 10: 449-469.

Even with the benefits 

of enhanced water use 

efficiency from elevated 

CO2 and slight increases 

in precipitation, dramatic 

increases in temperature 

can produce widespread, 

very rapid forest dieback, 

followed by infestations 

and fires. 
121

North America

(no fire suppression)

90

80

70

60

40

30

20

10

0

50

-10

1900 1925 1950 1975 2000 2025 2050 2075 2100

CGCM2-A2 CGCM-B2 CSIRO_MK2-A2

CSIRO_MK2-B2 HADCM3-A2 HADCM3-B2

Ecosystem carbon change (Pg)

Figure 3—Net gain or loss of carbon from North American Ecosystems under climate change (using 

an enhanced effect of CO2 on production and water use efficiency), without fire suppression.

North America

(fire suppression)

90

80

70

60

40

30

20

10

0

50

-10

1900 1925 1950 1975 2000 2025 2050 2075 2100

CGCM2-A2 CGCM-B2 CSIRO_MK2-A2

CSIRO_MK2-B2 HADCM3-A2 HADCM3-B2

Ecosystem carbon change (Pg)

Figure 4—Net gain or loss of carbon from North American Ecosystems under climate change (using 

an enhanced effect of CO2 on production and water use efficiency), with fire suppression.

Erik Ackerson, EarthDesign, Ink
122
123

Predicting Climate-Induced Range Shifts for Mammals: 

How Good are the Models?

Joshua J. Lawler 1, Denis White2, Ronald P. Neilson3, Andrew R. Blaustein4

1

David H. Smith Postdoctoral Fellow, Department of Zoology, Oregon State University, c/o U.S. Environmental Protection Agency, 200 SW 35th St., Corvallis, 

OR 97333; Email: Lawler.Joshua@epa.gov

2Geographer, U.S. Environmental Protection Agency, 200 SW 35th St., Corvallis, Corvallis, OR 97333; Email: white.denis@epa.gov

3USDA Forest Service, PNW Research Station, 3200 S.W. Jefferson Way, Corvallis, OR 97331; Email: rneilson@fs.fed.us

4Professor, Department of Zoology, Oregon State University, Corvallis, OR 97331; Email: blaustea@science.oregonstate.edu

Robert Karges II, U.S. Fish and Wildlife Service

Gary Kramer, U.S. Fish and Wildlife Service

Brian Anderson, U.S. Fish and Wildlife Service
124

Extended Abstract

Recent climatic changes have had clear impacts on biological systems 

(Parmesan and Yohe 2003, Root et al. 2003). Because changes in the 

earth’s climate in the coming century are predicted to be at least twice 

as large as those seen in the past 100 years (Houghton et al. 2001), we 

are likely to see even more dramatic changes in ecological systems. One 

of the basic responses to climate change is a shift in species geographic 

ranges (Parmesan et al. 1999). In order to manage wildlife and conserve 

biodiversity in the coming century, it is critical that we understand the 

potential impacts of climate change on species distributions. 

Several different approaches to predicting climate-induced geographic 

range shifts have been proposed to address this problem (Segurado and 

Araújo 2004). Unfortunately, no one approach has yet been found that 

consistently performs well for modeling a large number of species. We 

investigated the potential implications of using different bioclimatic 

modeling approaches for conclusions drawn about future climate-induced 

range shifts and extinctions. Using the current ranges of 100 mammal 

species found in the Western Hemisphere, we compared six methods for 

modeling their predicted future ranges including generalized linear models 

(McCullagh and Nelder 1989), classification trees (Breiman et al. 1984), 

generalized additive models (Hastie and Tibshirani 1990), random forest 

predictors (Breiman 2001), artificial neural networks (Ripley 1996), and 

genetic algorithms for rule-set prediction (GARP, Peterson et al. 2002). 

All approaches modeled current ranges as a function of current 

climate and current land cover. Models were built with a subset of 80 

percent of the data and tested using the reserved 20 percent of the data. 

Future ranges were predicted using predicted future climatic conditions 

and predicted future land cover. Future climate projections were taken 

from the Hadley Climate Centre’s HADCM2SUL model (Johns et 

al. 1997) using Intergovernmental Panel on Climate Change (IPCC) 

predicted future greenhouse gas contributions (IS92a) for the years 2061-

2090 (Kattenberg et al. 1996). Predicted future land cover was produced 

using the Mapped Atmospheric Plant-Soil-System model (MAPSS) 

(Neilson 1995). 

Predicted future distributions differed markedly across the alternative 

modeling approaches (e.g., fig. 1). These differences resulted in estimates 

of extinction rates that ranged from 0 to 7 percent, depending on which 

modeling approach was used. Random Forest predictors, a modelaveraging approach, consistently outperformed the other techniques 

(correctly predicting > 99 percent of current absences and 86 percent of 

current presences). Random forest models were the top-ranked model 

based on omission and commission error rates for 88 percent of the 

species. 

Our results support previous studies that conclude that uncertainties 

in bioclimatic models can be large, often overshadowing the uncertainty 

in climate-change predictions from general circulation models (Thuiller et 

al. 2004). We conclude that the types of models used in a study can have 

...to manage wildlife and 

conserve biodiversity in 

the coming century, it is 

critical that we understand 

the potential impacts of 

climate change on species 

distributions. 
125

Figure 1—Predicted range shifts for the Fisher Martes pennanti. Maps depict range shifts as predicted 

by six different modeling approaches using the same data set. Predictions are based on climate data 

produced by the HADCM2SUL general circulation model using IPCC predicted future greenhouse gas 

contributions (IS92a) for the years 2061-2090.

absent

stable

contraction

expansion

Generalized linear model Classification tree Generalized additive model

 Random forest model Artificial neural network Genetic algorithm for rule-set prediction

dramatic effects on predicted range shifts and extinction rates. Our work 

demonstrates one potential method for greatly reducing the uncertainty in 

predicted future range shifts. Random Forest predictors and other modelaveraging approaches will be important tools for accurately predicting 

range shifts in the face of climate change.

Keywords: Climate change, predictive modeling, climate-envelope, 

bioclimatic models, range shifts, species distributions.

References 

Breiman, L. 2001. Random forests. Machine Learning. 45: 5-32.

Breiman, L.; Friedman, J.H.; Olshen, R.A.; Stone, C.J. 1984. Classification and 

regression trees. Monterey, CA: Wadsworth and Brooks/Cole. 358 p.

Hastie, T.J.; Tibshirani, R.J. 1990. Generalized additive models. London: Chapman 

and Hall. 335 p.

Houghton, J.T.; Ding, Y.; Griggs, D.J.; Noguer, M.; van der Linden, P.J.; Dai, 

X.; Maskell, K.; Johnson, C.A. 2001. Climate change 2001: the scientific basis. 

Intergovernmental panel on climate change third assessment report. Cambridge, 

England: Cambridge University Press. 944 p.

Johns, T.C.; Carnell, R.E.; Crossley, J.F.; Gregory, J.M.; Mitchell, J.F.B.; Senior, 

C.A.; Tett, S.F.B.; Wood, R.A. 1997. The second Hadley Centre coupled oceanatmosphere GCM; model description, spinup and validation. Climate Dynamics. 

13: 103-134.
126

Kattenberg, A.; Giorgi, F.; Grassl, H.; Meehl, G.A.; 

Mitchell, J.F.B.; Stouffer, R.J.; Tokioka, T.; Weaver, 

A.J.; Wigley, T.M.L. 1996. Climate models: projections 

of future climate. In: Houghton, H.T.; Meira Filho, L.G.; 

Gallander, B.A.; Harris, N.; Kattenberg, A.: Maskell, K., 

eds. Climate change 1995: the science of climate change. 

Contribution of working group 1 to the second assessment 

report of the intergovernmental panel on climate change. 

Cambridge, England: Cambridge University Press: 285-357.

McCullagh, P.; Nelder, J.A. 1989. Generalized linear models. 

2nd edition. London: Chapman & Hall. 261 p. 

Neilson, R.P. 1995. A model for predicting continental scale 

vegetation distributions and water balance. Ecological 

Applications. 5: 362-385.

Parmesan, C.; Ryrholm, N.; Stefanescu, C.; Hill, J.K.; 

Thomas, C.D.; Descimon, H.; Huntley, B.; Kaila, L.; 

Kullberg, J.; Tammaru, T.; Tennent, W.J.; Thomas, J.A.; 

Warren, M. 1999. Poleward shifts in geographical ranges of 

butterfly species associated with regional warming. Nature. 

399: 579-583.

Parmesan, C.; Yohe, G. 2003. A globally coherent fingerprint 

of climate change impacts across natural systems. Nature. 

421: 37-42.

Peterson, A.T.; Ortega-Huerta, M.A.; Bartley, J.; SanchezCordero, V.; Soberon, J.; Buddemeier, R.H.; Stockwell, 

D.R.B. 2002. Future projections for Mexican faunas under 

global climate change scenarios. Nature. 416: 626-629.

Ripley, B.D. 1996. Pattern recognition and neural networks. 

Cambridge, England: Cambridge University Press. 416 p.

Root, T.L.; Price, J.T.; Hall, K.R.; Schneider, S.H.; 

Rosenzweig, C.; Pounds, J.A. 2003. Fingerprints of global 

warming on wild animals and plants. Nature. 421: 57-60.

Segurado, P.; Araújo, M.B. 2004. An evaluation of methods 

for modelling species distributions. Journal of Biogeography. 

31: 1555-1568.

Thuiller, W.; Araújo, M.B.; Pearson, R.G.; Whittaker, R.J.; 

Brotons, L.; Lavorel, S. 2004. Biodiversity conservation: 

uncertainty in predictions of extinction risk. Nature. 430.
127

Community Response to Climate 

Change and Forest Disturbance

Courtney G. Flint 1

1Assistant professor, Department of Natural Resources and Environmental Sciences, University of Illinois at Urbana-Champaign, W-503 Turner Hall, 1102 S. 

Goodwin Avenue, Urbana, IL 61801.

Courtney G. Flint

U.S. Fish and Wildlife Service
128

Introduction

Understanding climate change and its relationship with forest 

resources and communities involves a question of scale. Our 

understanding—or lack of understanding—of this interaction is 

complicated by a scale mismatch. We have global climate change models 

that provide scenarios with some regional and little local specificity 

(Cohen 1997, Wilbanks et al. 2003). At the regional scale, there are 

institutional structures and mechanisms for risk assessment and risk 

management related to environmental change (Haynes and Cleaves 

1999). At the community scale, locality studies emerge that are less 

generalizable and subject to much variation (Wilbanks et al. 2003). But 

environmental change is most immediately experienced at the community 

scale and this is where adaptation and response really take place on an 

everyday basis (Berkes and Jolly 2001, Flint and Luloff 2005). The large 

gap between the scale of forecasting models and the scale where extreme 

conditions and climate change are actually experienced is deserving of 

more attention.

Alaska is acutely experiencing climate change as highlighted in 

recent publications with broad distribution such as the New York Times

and High Country News. Berman et al. (1998) referred to a number of 

potential effects of climate change on Alaskan forest environments. These 

included: increased risk of wildfires; increased insect epidemics, increased 

windthrow; hydrological changes; reforestation failures; changes in the 

range of terrestrial and aquatic species; and changes in the range of tree 

species and ecotypes. Turning to the human community dimension of 

climate change and forest resources, a few questions emerge:

l How do risks from the relationship between climate change and 

forest resources affect local communities?

l What are the impacts and risks from climate change and forest 

disturbance perceived by local residents?

l What is the range of community vulnerability and community 

capacity to respond to the effects of climate change on forest 

ecosystems?

Risk Assessment and 

Community Perceptions

There are a number of important considerations for communities 

when assessing climate change risks. Technical risk assessments often 

neglect risk perceptions or the more subjective interpretations, concerns, 

or anxieties about things that might go wrong (Crawford-Brown 1999). 

These risk perceptions often coalesce and are shared at the community 

level (Fitchen et al. 1987). Community risk perceptions can affect 

levels of local engagement and responses to environmental change and 

natural resource management. Kasperson et al. (1988) suggested that 

risk is often amplified or attenuated by regional or local ‘stations’ where 

communication plays a key role in how risk perceptions emerge and 

The large gap between 

the scale of forecasting 

models and the scale where 

extreme conditions and 

climate change are actually 

experienced is deserving of 

more attention.

Community risk perceptions 

can affect levels of local 

engagement and responses 

to environmental change 

and natural resource 

management.
129

grow, whether they emerge at all, and how they fade away. Local opinion 

leaders and groups play key roles in shaping perception and motivating 

local response (Wondolleck and Yaffee 2000). Berkes and Jolly (2001: p1) 

suggested that, “The inevitable surprises of climate change will unfold 

on a regional and local stage.” Therefore, if we are to accurately assess 

risk situations related to environmental change such as climate change 

and consequent forest disturbances, we need to more fully appreciate 

not only the biophysical characteristics of the local scale, but the human 

dimensions of the local scale as well.

Communities are at an important scale for risk analysis and 

management. Risk perceptions are shared at this level, thus filtering 

changing perceptions of individuals. Collective actions based on such 

perceptions can have consequences for natural resource management. 

Local actions can either facilitate or impede forest management decisions 

and strategies. For example, a community having lower risk perceptions 

than technical risk assessments may mobilize opposition to forest riskmitigation treatments. On the other hand, a community with higher risk 

perceptions than technical risk assessments may take matters into their 

own hands to mitigate risks.

In forest-based communities, there is generally an intimate 

relationship between a changing environment and everyday life. 

Information is often gathered by direct personal experience rather than 

from information sources such as media or agency education efforts. This 

direct experience increases local knowledge of environmental processes 

and shapes decision-making by local individuals. 

A critical problem in natural resource management is that there are 

often rampant assumptions of homogeneity when describing or dealing 

with forest-based communities. Communities are often treated as if 

they are all the same with the same vulnerabilities, histories, experiences, 

capacities, and characteristics. In fact, the relationship between 

communities and forests is very multi-faceted (Christensen and Donohue 

1991). Timber and non-timber resources, scenic and aesthetic values, 

tourism and recreation interests, quality of life, and multiple ecological 

values are all part of how local communities interact with forest resources. 

Based on what we know about the heterogeneity in society and across 

communities, we can’t continue to sweep even adjacent communities into 

the same category out of hand. How communities respond to changing 

forest conditions related to climate change depends on contextual factors 

that should be extensively assessed as part of regional or landscape risk 

assessments. 

Implications from the 

Kenai Peninsula, Alaska

Findings from research on the Kenai Peninsula, Alaska illustrate 

the important relationships between climate change, forest disturbance, 

and community response (Flint, in press; Flint 2004; Rapp 2005). On 

the Kenai Peninsula, spruce bark beetles have killed over 80-90 percent 

 if we are to accurately 

assess risk situations related 

to environmental change 

such as climate change 

and consequent forest 

disturbances, we need 

to more fully appreciate 

not only the biophysical 

characteristics of the local 

scale, but the human 

dimensions of the local 

scale as well.

How communities 

respond to changing forest 

conditions related to 

climate change depends 

on contextual factors that 

should be extensively 

assessed as part of 

regional or landscape risk 

assessments. 
130

of spruce trees across over 1 million acres (Ross et al. 2001). Local 

community responses to the disturbance frustrated forest management 

and forest management strategies frustrated local community residents.

The spruce bark beetle (Dendroctonus rufipennis) is endemic or native 

to the area but the outbreak that peaked in the 1990s on the Kenai 

Peninsula was unprecedented. One of the most common hypotheses 

about why the current outbreak of these beetles are covering larger areas 

and causing greater mortality than usual is the warming trend in southcentral Alaska. This warming trend is reducing host tree resistance and 

reducing beetle generation time (Berman et al. 1998). A locally based 

ecologist, Ed Berg, who works for the US Wildlife Refuge on the Kenai 

Peninsula, supports this hypothesis (Berg 2003). What is important about 

this from a community standpoint is that Ed Berg has become almost a 

household name on the Kenai Peninsula. Many local residents interviewed 

referred to him in their discussions of the spruce bark beetle outbreak 

and linked their understanding of the role of climate change in the Kenai 

Peninsula forest disturbance to Ed Berg and not to larger scale media 

exposure.

This supports the notion that key opinion leaders are important 

to how risks are ‘amplified’ across local and regional scales and how 

local understanding of environmental issues are framed. Interestingly, 

this particular expert is cited by environmentalists and timber industry 

supporters alike as well as those in the middle. He serves as a bridge 

between these disparate interests. This type of individual is a key resource 

for natural resource managers.

People pay close attention to environmental changes. One resident 

from Anchor Point, Alaska said, “The first year we were here it was 

45 below in the winter. We haven’t seen that in a long time.” Another 

resident from Ninilchik, Alaska said, 

What caused the spruce beetle thing in my opinion? I’m no 

scientist, but it’s global warming! The temperature has come up. 

Oh yes! When it gets to 67 degrees, these beetles come out and 

attack the trees.

It’s an emotional response. The immediate experience with forest 

disturbance registers deeply with people who live, work, and play in and 

around forest-based communities. A resident from Homer, Alaska said,

You work so hard to become comfortable and acclimated in your 

environment. When that changes around you, you feel so out of 

control with that change. It’s one thing to decide, ‘I’m going to cut 

down those trees or put a road in here.’ But to have that imposed 

on you... It’s totally out of your control and it was very emotionally 

upsetting for a lot of people. Very sad. A number of people just 

looked at their dead trees and just sobbed.

On the Kenai Peninsula, the type and level of risk perception 

varied from one community to another and was strongly influenced by 

experience and local factors (Flint 2004). Factor analysis of mail survey 

data from 1,088 local residents from six Kenai Peninsula communities 

The immediate experience 

with forest disturbance 

registers deeply with people 

who live, work, and play 

in and around forest-based 

communities.
131

showed two distinct factors of risk perceptions that were correlated but 

not collinear. The first factor was immediate threats to personal safety and 

property including forest and grass fire and falling trees. The second factor 

was broader threats to community and ecological well-being. This factor 

included risk perceptions related to scenic and aesthetic qualities, local 

identity, watersheds, habitat, jobs and other economic factors (Flint, in 

press). 

Multiple regression analysis of survey data revealed that broader 

threats had a strong relationship with participation in community 

action (Flint 2004). On the other hand, immediate threats did not 

affect community action participation despite that these concerns were 

typically higher than concerns about broader well-being. In other words, 

participation in some form of community action, such as attending a local 

meeting or opposition to a timber sale, was influenced by risk perceptions 

of broader threats to well-being rather than concerns about wildfire or 

falling trees. On the Kenai Peninsula, forest managers have focused on 

mitigating the risk of wildfire. Flint’s research suggests that though people 

are generally concerned about fire, broader concerns about community 

and ecological well-being are more likely to motivate involvement in local 

community action.

Implications and Conclusions

These findings have a number of implications for managing climate 

change and forest disturbances. First, we should assume heterogeneity 

across communities situated in changing landscapes, not homogeneity. 

Community assessments along biophysical, sociodemographic, cultural, 

and economic dimensions will help to systematically categorize and 

understand local community differences. Second, resource managers 

should tap into local capacities to motivate participation and involvement 

in decision-making. This includes identifying and involving local 

opinion leaders and recognizing local knowledge arising from lengthy 

direct experience with local environments. Third, risk analyses should 

incorporate local risk perceptions in addition to technical risk assessments. 

Integrating risk perceptions with risk assessments helps to highlight 

priority areas for risk mitigation as well as areas of disagreement where 

more sensitivity may be needed to avoid protracted conflict over natural 

resource management. Fourth, we should appreciate broader threats to 

community and ecological well-being, not just potential for catastrophic 

events and their economic costs. These efforts would help to engage the 

local scale over the long-term to deal with dynamic environmental and 

community change. Bringing local communities into natural resource 

management contributes to sound decision-making that is more likely to 

be broadly recognized and accepted from multiple perspectives.

 ...though people are 

generally concerned about 

fire, broader concerns about 

community and ecological 

well-being are more likely 

to motivate involvement in 

local community action.

Community assessments 

along biophysical, 

sociodemographic, cultural, 

and economic dimensions 

will help to systematically 

categorize and understand 

local community differences. 
132

References

Berg, E. 2003. Refuge notebook of the Kenai National 

Wildlife Refuge. http://alaska.fws.gov/nwr0/kenai/

notebook/2003. February 20, 2004.

Berman, M.; Juday, G.P.; Burnside, R. 1998. Climate change 

and Alaska’s forests: people, problems, and policies. In: 

Weller, G.; Anderson, P.A., eds. Proceedings, Assessing the 

consequences of climate change for Alaska and the Bering 

Sea region. Fairbanks, AK: Center for Global Change and 

Arctic Systems Research, University of Alaska, Fairbanks: 

21-42.

Berkes, F.; Jolly, D. 2001. Adapting to climate change: 

socio-ecological resilence in a Canadian Western Arctic 

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Christensen, H.H.; Donoghue, E.M. 2001. A research 

framework for natural resource-based communities in 

the Pacific Northwest. Gen. Tech. Rep. PNW-GTR-515. 

Portland, OR: U.S. Department of Agriculture, Forest 

Service, Pacific Northwest Research Station. 21 p.

Cohen, S.J. 1997. Scientist-stakeholder collaboration in 

integrated assessment of climate change: lessons from a case 

study of Northwest Canada. Environmental Modeling and 

Assessment. 2: 281-293.

Crawford-Brown, D. 1999. Risk based environmental 

decisions: methods and culture. Boston, MA: Kluwer 

Academic Publishers. 224 p. 

Fitchen, J.M.; Heath, J.S.; Fessenden-Raden, J. 1987.

Risk perception in community context: a case study. In: 

Johnson, B.B.; Covello, V.T., eds. The social and cultural 

construction of risk. Boston, MA: D. Reidel: 31-54.

Flint C.G. [In press]. Community perspectives on spruce 

beetle impacts on the Kenai Peninsula, Alaska. Forest 

Ecology and Management.

Flint, C.G. 2004. Community response to forest disturbance 

on Alaska’s Kenai Peninsula. University Park, PA: The 

Pennsylvania State University. 297 p. Ph.D. dissertation.

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communities, risk, and disaster: an intersection of theories. 

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133

Climate Change and Community Resilience: 

A Knowledge Management Exercise 

Trista Patterson1

1Research Social Scientist, USDA Forest Service, Pacific Northwest Research Station, 2770 Sherwood Ln. Suite 2A, Juneau AK, 99801. 

Email: tmpatterson@fs.fed.us

Tom Iraci, USDA Forest Service
134

Abstract 

Northern renewable-resource based communities are vulnerable to 

climate change in many ways. Developing a strategy to deal with these 

vulnerabilities requires integration of information, both at multiple scales 

and among modes of inquiry. A number of factors have been identified 

in contributing to community resilience (social capital, human capital, 

resource security, economic diversity, participative democracy, appropriate 

infrastructure, etc). However, research which addresses human activity 

as a driver of climate is often juxtaposed against the findings of research 

which addresses climate change’s impact on humans. While the former 

implies the need for mitigation, the latter stresses adaptation. This is 

problematic because public funds for problem solving are limited, and 

adaptation and mitigation can appear as mutually exclusive strategies. A 

systems perspective illustrates how both adaptive and mitigative capacities 

are necessary to bring climate into natural resource management. This 

paper presents a knowledge management exercise designed to challenge 

participants to consider the integrative value of their work. A conceptual 

model of the system allowed individual conference attendees to identify 

the locus and extent of their work with respect to eight disciplinary 

approaches and nine spatial scales. The poster was interactive, and 

designed to call attention to system feedbacks and drivers that would 

otherwise be obscured. The result was a collectively generated diagram 

which highlighted knowledge clusters and gaps. Participant discussion 

focused on linkages between studies, and the spatial and conceptual 

extensions of the identified works. 

Keywords: Knowledge management, community response, climate 

change.

Introduction 

Addressing climate change vulnerabilities to Northern renewableresource based communities means optimizing among costs and benefits 

of various interventions. Optimization is a technique best executed under 

linear conditions. It is less effective when applied to non-linear / emergent 

phenomena or multiple scales, but becomes intractable when an issue 

becomes demonstrably polarized. 

Community stress and polarization often rises when groups must 

reorient around shifting resource bases (such as those affected directly 

or indirectly by climate change) (Tannen 1999). Many studies have 

speculated on the various contributors to community resilience (social 

capital, human capital, resource security, economic diversity, participative 

democracy, appropriate infrastructure, etc.), leading to a wide variety of 

perspectives on the same issue. Organizing this information strategically 

can improve ability to examine linkages, compare among cases and spatial 

scales, and respond to new information, while adding little cost to existing 

projects. This paper presents a knowledge management exercise designed 

to facilitate information sharing among those who work on “pieces of the 

puzzle” or to facilitate consensus on a “sense of the whole.”

Organizing...information 

strategically can improve 

ability to examine linkages, 

compare among cases and 

spatial scales, and respond 

to new information...
135

As applied to ecosystems, or to integrated systems of people and 

the natural environment, resilience has three defining characteristics: 

the amount of change the system can undergo and still retain the same 

controls on function and structure, the degree to which the system is 

capable of self-organization, and the ability to build and increase the 

capacity for learning and adaptation (Holling 1973, 2000) (Carpenter et 

al. 2001). Resilience in social systems also involves the human capacity 

for anticipating and planning for the future. Social resilience relates to 

community adaptive capacity, in that, in social systems, the existence of 

institutions and networks that learn and store knowledge and experience, 

create flexibility in problem solving and balance power among interest 

groups, playing an important role in adaptive capacity (Berkes et al. 2002, 

Scheffer et al. 2000). 

Addressing how people respond to periods of change, how society 

reorganizes following change, is the most neglected and least understood 

aspect in conventional resource management and science (Gunderson 

and Holling 2002). Scalar and integrated investigations are necessary 

because climate is a global, not local phenomenon. However, little 

emphasis is placed on articulating a well-formed conceptual model, to 

which multiple contributors can reference their work (Adams et al. 2003). 

Effective knowledge management can make scarce resources go further 

by extracting tacit knowledge from contributors, encapsulating shared 

knowledge and structuring consensus, facilitating productive discourse, 

identifying knowledge gaps, defining shared goals and strategies, and 

informing others and extending knowledge applications. 

Method 

The “bulls-eye” model has been used in a number of formats to 

address the complexity of climate change, both from disciplinary and 

spatial perspectives (Patterson et al., in press; Patterson 2004). A bullseye model was modified to reflect the content of the proposed conference 

content. As the conference presenters delivered their talks, the conceptual 

range and spatial extent of their talk was mapped on the diagram, and 

identified with letters. During the conference breakout sessions, the 

bulls-eye diagram was presented to conference participants, and they 

were invited to locate their primary area of interest on the diagram, and 

to indicate with whisker lines the extent of the conceptual and spatial 

application of their work. Each participant was assigned a number, so that 

other conference attendees could reference their work. 

Diagram Description 

The concentric circles on the diagram refer to the relevant spatial 

scales (concentric circles I-IX) of the work, with the most local work the 

subject of the smallest circle and work referencing global scales located at 

the outer circle (fig. 1). The boxes surrounding the outer circle represent 

research concerning state functions (labeled A-G) that in theory can be 

quantified and tracked over time. The numbered arrows represent research 

on change functions (labeled 1-8). A dynamic model would consider 

Effective knowledge 

management can make 

scarce resources go further...
136

these as “stock” versus “flow.” These are explorations of relationships 

between two or more state functions, and their dynamics over time.

To understand the relationship between various components it is 

useful (though not necessary) to discuss them in a clock-wise fashion. 

Beginning with the bottom of the diagram, human activity and natural 

variability influence climate at local to global scales. Area (A) refers to 

attempts to document the State of Climate at each of these scales. Arrow 

(1) concerns the qualitative and dynamic relationship between climate 

variability and ecological and infrastructure resilience. Studies falling 

into region (B) are attempts to document the State of Ecological and 

Infrastructure Resilience by taking a more quantified approach. The 

amount of change these systems can undergo and still retain function and 

structure is the subject of area (2). Assessments of the State of Built or 

Natural Capital fall into section (C). The relationship between that capital 

and the way people derive satisfaction from consuming it, is the area of 

concern of arrow (3). Economics as a discipline is often concerned with 

maximizing the result: State of Utility (D). Studies of how people assess 

worth, fairness, risk, are all processes related to region (4). Social science 

surveys often document States of Perception (E). Much recent work has 

been done on how these perceptions are communicated and shared among 

stakeholders (5). The quantifications of networks, trusts and norms fall 

under documentation of the State of Social Capital and civic participation 

(F). Studies in area (6) examine the process by which as groups act in 

collective fashion, garnering resources and ultimately, maximizing net 

social benefit. Group capacity for self-organization, adaptation, mitigation 

Figure 1—The knowledge management framework. Concentric circles I-IX represent increasing spatial 

scale. Letters A-H represent state variables, or data that can reflect a snapshot of the dynamic system at a 

given moment in time. Numbers 1-8 represent various disciplines and study of relations between variables.

1.

3.

4.

5.

6.

7.

2.

8.

E. State of Perception

F. State of Social 

Capital

G. State of 

Social 

Resilience

H. State of Human

Activity

A. State of Climate

 B. State of

Ecological and

Infrastructure

Resilience

C. State of 

Built and

Natural 

Captial

D. State of Utility

(benefit derived from

goods and services)

Holling, 2000

I. Global

II. International

III. Nation

IV. Region

V. Forest

VI. Ranger District

VII. 

VIII. 

IX.
137

and continuing to maximize net social benefit in the face of change, falls 

under the category State of Social Resilience (G). The process by which 

this resilience is able to effect changes in human activity is the area of 

concern (7). Quantification of Human Activity, including economic 

structure and intervention such as taxes or incentives falls into area (H). 

In typical feedback form, this human activity mediates drivers responsible 

for climate change, the topic of investigations in region (8).

Results

The conference participants mapped their interests on the diagram, 

and used whisker lines to indicate when their work referenced more than 

one spatial scale. They drew whisker arcs around the circle from their ‘data 

point’ to refer to their work’s disciplinary breadth, as illustrated below (fig. 

2). A total of 10 conference presentations (represented by numbers), and 

thirteen attendees (represented by letters) were mapped on the diagram. 

Presentations that were located on the diagram were sessions presented 

by (1) R.Nielson and J. Townsley; (2) L.Joyce and J. Morgan; (3) P.Mote, 

(4) B. Harding, K.Martin, S.Malloch; (5) L.Ziska; (6) J.Logan, (7) 

R.Rosenberger, D.Adams, C.Flint, D.Cox; (8) M.Delaney; (9) B. Carlson; 

(10) K. Redmond. Conference attendees who participated in mapping 

their interests on the diagram were (A) C. Flint, (B) B. Musik, (C) R. 

Rosenberger, (D) J.Lawler, (E) P.Bedlow, (F) A.Ray, (G) A.Kennedy, (H) 

C.Nitchke, (I) P.Glick, (J) S.Wall, (K) S.Wall, (L) E. Bella, and (M) D. 

Chew.

Figure 2—Participants drew their research interests upon the diagram, using whisker lines to express the 

disciplinary extent and spatial scale of their work. Numbers represent conference presentations, while 

letters represent conference audience members. 
138

Discussion 

This paper describes the use of a systems diagram, with which 

conference attendees were asked to consider conceptual pieces of the 

diagram in clockwise fashion. This depiction should not be taken to 

indicate that this is a linear process, the system components can be 

arranged in any number of ways. The benefits of knowledge layout in 

this manner, however, did confer a number of benefits. It counteracted 

the tendency to polarize between two concerns, namely how climate 

change is affecting communities versus how communities are driving 

climate change. First, the diagram helped facilitate dialog in common 

terms of how to maximize net social benefit, without making those 

concerns mutually exclusive. Second, it helped conference attendees to 

visually identify “knowledge clusters” and gaps. Most of the conference 

presentations and attendee interests were mapped to the lower lefthand corner of the diagram, namely the area associated with the state of 

ecological and infrastructural resilience. Many of the references to the 

economic discipline referred to the area between C and D, that is, the 

relationship between natural capital and the way people derive satisfaction 

from consuming it. The fewest references were made to work done on the 

state of benefit derived from goods and services (area D) and the state of 

social perception (area E), or how that might influence social function in 

the form of social capital (area F). Several participants noted that it might 

be interesting, (though challenging) to recruit presenters on this area 

(namely the social sciences) in the future. 

A third product of the diagram was that it challenged exercise 

participants to consider the drivers of climate change, as well as climate 

change impacts. While conference participants noted that this was an 

important contributor to the system dynamics, many noted the challenge 

of encompassing such considerations in future conference events. 

A final contribution of the diagram was that it allowed conference 

participants to explicitly address associations between scales and system 

components. While many researchers were collecting information at the 

forest or regional scale, very few referenced the global, or very site-specific 

scales. The lack of operative “community” at the global scale was noted 

to be a barrier to collective problem solving at this level. This is a notable 

gap, as climate change is a global, not localized problem, and as such 

studies which operate at a more localized scale but are unable to reference 

the broader global scale may have limited application to solving the 

serious challenges climate presents. Many commented on the proximity 

of other researchers to their own areas of interest, and remarked on the 

possibility of collaboration with other researchers in similar areas, but 

acting at different scales, or conversely researching at similar scales but on 

different system components. 

These associations are critical for integrative studies in the future. 

This exercise was an interactive experiment with a conference audience 

that had expressed in the breakout discussions some tendency to view 

climate mitigation and adaptation as mutually exclusive strategies. The 

process of drawing individuals’ research or interest areas on the diagram 

...the diagram helped 

facilitate dialog in common 

terms of how to maximize 

net social benefit, without 

making those concerns 

mutually exclusive.

This exercise was an 

interactive experiment 

with a conference audience 

that had expressed in the 

breakout discussions some 

tendency to view climate 

mitigation and adaptation as 

mutually exclusive strategies. 
139

helped identification of knowledge clusters and gaps at the conference. 

Facilitation of knowledge transfer both among disparate fields of research, 

and extending findings to other scales of inquiry can compound the value 

of existing studies with little added cost. 

References 

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Two-way street or vicious/virtuous circle? Journal of Sustainable Tourism.

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Tannen, D. 1999. The argument culture. New York: Ballantine. 384 p . 
140
141

Beedlow, P. 

Rising Atmospheric CO2

and Carbon Sequestration 

in Forests

 Rising CO2 concentrations in the atmosphere 

could alter Earth’s climate system, but it is thought 

that higher concentrations may improve plant growth 

through a process known as the “fertilization effect.” 

Forests are an important part of the planet’s carbon 

cycle, and sequester a substantial amount of the CO2

released into the atmosphere by human activities. 

Many people believe that the amount of carbon that 

forests sequester will increase as CO2 concentrations 

rise. An increasing body of research suggests, however, 

that the fertilization effect is limited by nutrients and 

air pollution, in addition to the well documented 

limitations posed by temperature and precipitation. 

This review suggests that existing forests are not 

likely to increase sequestration as atmospheric CO2

increases. Therefore, it is imperative that we manage 

forests to maximize carbon retention in above- and 

below-ground biomass and conserve soil carbon.

Peter Beedlow, US Environmental Protection Agency, 

Corvallis, OR. (541) 754-4634. 

email: beedlow.peter@epamail.epa.gov

Bella, Elizabeth

Invasive Plant Expansion into 

Biogeoclimatic Envelopes 

under Current Climate and 

Global Climate Change 

Scenarios in Alaska

Alaska has long been considered immune to 

large-scale biological invasions due to its climate and 

its relative geographical isolation, but increased trade 

and travel to the state, as well as a changing climate, 

have begun to change this perception. A multi-agency 

approach of inventory, monitoring, education, and 

research is starting to define and plan for the complex 

problems of ecological, economic, and social effects 

of invasive plants on public lands in Alaska. This 

project aims to, over the next three years, increase 

our understanding of the biogeoclimatic mechanisms 

for invasive species range expansion in Alaska, and 

provide management recommendations for public 

lands agencies under a changing climate. We have 

determined a list of invasive species of concern for this 

study based on literature reviews of similar or identical 

species and their behavior in similar climates, and have 

started to model the current biogeoclimatic ranges 

of these higher-risk species using range envelope 

Combined set of Poster 

Presentation abstracts for the

“Bringing Climate into Natural Resource 

Management” Conference

being held on June 28-30, 2005 

at the Hilton Hotel, Portland

Prepared by Gary Benson

June 10, 2005
142

models and Alaska climate and GIS data. Range 

envelope models have previously have been applied to 

rare plant range reductions, but have great potential 

for application to invasive species range expansion 

determinations. We next plan to utilize Global 

Circulation Models (GCMs) to predict the same 

species ranges one hundred years in the future under 

different climate change scenarios, and to compare 

current and future ranges determine to changes in 

ranges, patterns of change, and rate of movement of 

species over the landscape. The results of this study 

will include the creation of detailed maps of current 

and future biogeoclimatic ranges of the selected 

invasion species in order to direct management efforts 

to control of higher-risk species, and to provide a 

template for predicting other species range expansions 

in Alaska and in similar northern climates.

Elizabeth Bella, Department of Environmental 

Science and Policy, University of California, Davis, 

2101C Wickson Hall, One Shields Avenue, 

Davis, CA 95616

(530) 752-6003; email: ebella@fs.fed.us.

Professional Affiliation: Chugach National Forest, 

Seward Ranger District

Chew, J.; Bollenbacher, B.; and C. Stalling

Modeling Impacts On The 

Levels Of Sustainable 

Resources From Increased 

Wildfire Acres Associated With 

Potential Climate Changes

The impact that changing climates may have on 

the ability to sustain natural resource goals over a 300 

year planning horizon for a national forest is examined 

by using a spatially explicit, stochastic, landscape-level 

simulation model. A national forest in the northern 

Rocky Mountains is simulated to examine different 

levels of wildfire, insect and disease activity that 

would result from warm and dry cycles and a higher 

probability of extreme fire events over the planning 

period. Differences in the long-term sustained yield 

for wood products, acres that have the potential to 

provide old growth conditions, the frequency of 

wildfire having a significant impact on water quality 

and the acres of wildfire in a wildland urban interface 

are compared. Two levels of fuel-reduction treatments 

are examined for the scenario that results in the 

highest level of wildfire over the planning period. 

Jimmie D. Chew, Forester, Rocky Mountain Research 

Station, USDA Forest Service, 800 E. Beckwith, 

Missoula, MT 59807 

(406) 542-4171; email: jchew@fs.fed.us

Barry Bollenbacher, Regional Silviculturist

Regional Office, Northern Region, 

USDA Forest Service, Missoula, MT

(406) 329-3297; email: bbollenbacher@fs.fed.us

Christine Stalling, Biologist, Rocky Mountain 

Research Station, USDA Forest Service

800 E. Beckwith, Missoula, MT 59807

(406) 542-4153; email: cstalling@fs.fed.us

Laskowski, M. and L.A. Joyce

Natural Resource Managers 

Respond to Climate Change:

A Look at Actions, Challenges, 

and Trends

Natural resource managers in the Western U.S. 

are progressively responding to concerns about 

current and future climate change. Some of the 

catalysts include increases in impacts observed on 

climate-sensitive resources, increases in extreme 

weather events, heightened levels of public interest 

and concern, and extensive scientific evidence. We 

assessed the types of active measures western natural 

resource managers are taking in response to potential 

climate-change effects. The spectrum of responses 

was categorized as follows: awareness and discussion, 

assessment, monitoring, research, education and 

outreach, policy and planning, field-based activities, 

and mitigation. Activities ranged from holding 

informal meetings and specialized workshops within 

the institution to creating educational bulletins 

and exhibits for the public. Activities to develop a 

better information database included vulnerability 

assessments and initiating long-term monitoring. 

Further activities ranged from creating formal 

strategies, management plans, prescribed burning 

and grazing, to carbon sequestration and green house 

gas reduction. Challenges were associated with all 

active responses. Understanding current and future 

climate changes and deciphering their impact on the 

ecosystem as well as uncertainty about what and how 
143

much to do about it posed significant challenges. 

Other challenges include limited resources (human, 

financial, technological, and time) and lack of 

institutional interest. In general, managers responded 

to climate-change concerns when there were obvious 

incentives (e.g., improved grazing conditions, 

improved hydropower capacity). Those who oversee 

climate-sensitive resources, and/or who work in areas 

that have experienced extreme climate events or 

climate variability (e.g., droughts, landslides) have also 

responded with management actions. Additionally, 

managers receiving specific guidance on planning for 

climate change from partnerships with climate-focused 

organizations, extension staff, and/or scientists were 

more prepared to respond. 

Michele Laskowski, Contractor, SI Inc, 240 West 

Prospect, Fort Collins, CO 80526 

(970) 498-1123

Dr. Linda Joyce, Rocky Mountain Research Station

240 West Prospect, Fort Collins, CO 80526

(970) 498-2560; email: ljoyce@fs.fed.us

Kennedy, Adam M. 

The Influence of El Niño-related 

Sea-Surface Temperature 

Gradients (Trans-Niño Index) 

on Upper Klamath Basin 

Stream Discharge 

This research investigates large-scale climate 

variables affecting inter-annual hydrologic variability 

of streams flowing into Upper Klamath Lake, 

Oregon. Six indexes: the Pacific North American 

Pattern, Southern Oscillation Index, Pacific Decadal 

Oscillation (PDO), Multivariate ENSO Index, Niño 

3.4, and a revised Trans-Niño Index (TNI) were 

evaluated independently for their ability to explain 

inter-annual variation of the Upper Williamson River, 

Sprague River, Upper Klamath Lake net inflow, and 

Crater Lake snow water equivalent (SWE). The TNI, 

which measures the sea-surface temperature gradient 

between region Niño 1+2 and region Niño 4, was the 

only index to show significant correlations during the 

current warm phase of the PDO. During the warm 

PDO phase (1978-present), the averaged October 

through December TNI was strongly correlated (a

= 0.05) with the following April through Septemer 

Upper Williamson River discharge (r = 0.73), Sprague 

River discharge (r = 0.65), net inflow to Upper 

Klamath Lake (r = 0.68), and moderately correlated 

with observed Crater Lake April 1st SWE (r = 0.52). 

 These results suggest that warm PDO phase 

equatorial sea-surface temperature gradients, as 

opposed to mean sea-surface temperature or sea-level 

pressure patterns, explain a large portion of hydrologic 

variability observed in the Upper Klamath basin. 

Furthermore, additional analysis indicated regionalscale correlations, which may extend the usefulness of 

the TNI outside of the Upper Klamath basin. Thus, 

the TNI may prove useful for long-lead stream flow 

forecast operations, ecosystem-scale modeling, and a 

variety of other environmental science applications. 

Adam M. Kennedy, Environmental Sciences and 

Resources, Portland State University, PO Box 751

Portland, Oregon 97207, email: kenna@pdx.edu

Professional affiliation: Natural Resources 

Conservation Service (NRCS), Portland, Oregon

L. Kruger and T. Patterson 

Knowledge Management for 

Climate Change in Northern 

Renewable-Resource Based 

Communities 

Addressing climate change vulnerabilities to 

Northern Renewable-Resource Based Communities 

(NRRBCs) means optimizing among costs and 

benefits of various interventions. Optimization is a 

technique best executed under linear conditions. It 

is less effective when applied to non-linear/emergent 

phenomena or multiple scales, but becomes intractable 

when an issue becomes demonstrably polarized. 

Polarization frequently occurs when groups are 

under stress. Community stress often rises when 

groups must reorient around shifting resource bases 

(such as those affected directly or indirectly by climate 

change). While many studies have speculated on the 

various contributors to community resilience (social 

capital, human capital, resource security, economic 

diversity, participative democracy, appropriate 

infrastructure, etc), organization of the resulting 

information has been less strategic. We suggest this 
144

as a leverage point that could improve a community’s 

ability to examine linkages, compare among cases 

and spatial scales, and respond to new information, 

while adding little cost to existing projects. This 

poster explores one way complex information might 

be shared among those who work on “pieces of the 

puzzle,” or how it might be presented to those who 

desire some “sense of the whole” before making policy 

decisions.

We present a conceptual model of the system, 

visually reorganizing factors affecting community 

resilience to call attention to system feedbacks and 

drivers that would otherwise be obscured. Ultimately, 

we aim to provide the basis for increased collaboration 

among disparate fields of research, identification of 

knowledge gaps and facilitation of knowledge transfer.

Linda Kruger and Trista Patterson, USDA Forest 

Service, Pacific Northwest Research Station, 2770 

Sherwood Ln. Suite 2A, Juneau AK, 99801 

Contact email: tmpatterson@fs.fed.us

Lawler, J.; White, D.; Neilson, R.; 

and A. Blaustein

Predicting Climate-induced 

Range Shifts for Mammals: 

How Good are the Models?

In order to manage wildlife and conserve 

biodiversity, it is critical that we understand the 

potential impacts of climate change on species 

distributions. Several different approaches to 

predicting climate-induced geographic range shifts 

have been proposed to address this problem. We 

investigated the potential implications of using these 

different approaches for conclusions drawn about 

future range shifts and extinctions. Using the current 

ranges of 100 mammal species found in the western 

hemisphere, we compared six methods for modeling 

their predicted future ranges. All approaches modeled 

current ranges as a function of current climate and 

current land cover. Future ranges were predicted using 

predicted future climatic conditions from a global 

circulation model and predicted future land cover 

from a process-based equilibrium vegetation model. 

Predicted future distributions differed markedly 

across the alternative modeling approaches, resulting 

in estimates of extinction rates that ranged between 

0 and 7 percent, depending on which modeling 

approach was used. Random forest predictors, a 

model-averaging approach, consistently outperformed 

the other techniques (correctly predicting > 99 

percent of current absences and 86 percent of current 

presences). We conclude that the types of models used 

in a study can have dramatic effects on predicted range 

shifts and extinction rates; and that model-averaging 

approaches appear to have the greatest potential for 

predicting range shifts in the face of climate change.

Joshua J. Lawler, Department of Zoology, Oregon 

State University, c/o US Environmental Protection 

Agency, 200 SW 35th St., Corvallis, OR, 97333, USA. 

(541) 754-4834. email: lawler.joshua@epa.gov.

Denis White, US Environmental Protection Agency, 

200 SW 35th St., Corvallis, OR, 97333, USA. 

(541) 754-4476. email: white.denis@epa.gov.

Ronald P. Neilson, US Forest Service, 3200 SW 

Jefferson Way, Corvallis, OR, 97331, USA. 

(541) 750-7303. email: rneilson@fs.fed.us

Andrew R. Blaustein, Department of Zoology, 

Oregon State University, Corvallis, OR, 97331, USA. 

(541) 737-5356. 

email: blaustea@science.oregonstate.edu

Nitschke, Craig and J. L. Innes

Impact of Climate Change on 

Landscape-level Fire Severity 

Ratings in the North Okanagan, 

British Columbia, Canada

For forest managers, one of the most important 

aspects of climate change that need to be considered 

is how climate change will impact the effects of 

disturbances, including both natural disturbances and 

those induced by management activities. With global 

climate change models (GCMS) predicting increased 

warming of between 2 and 5°C with little or no 

change in precipitation in Western Canada, it seems 

likely that increased summer continental drying could 

result in an increased risk of drought and an increase 

in fire severity and frequency. To determine the affect 

of potential climate change on the fire severity ratings 

for a 145,000 ha landscape located in the North 

Okanagan region of British Columbia, Canada, 

an analysis was conducted using three GCMS, five 

weather stations, and the Canadian Forest Fire Danger 
145

Rating System. The analysis compared the predictions 

of three GCMS: CGCM1, CGCM2, and Hadley 

CM3. Each GCM affected the fire severity ratings 

differently, with the Hadley model having the greatest 

and most divergent impact. The results suggest that 

by 2100, the mean fire season length may increase by 

30 percent, with 90 percent of this increase occurring 

in the spring (Mar-May). By 2100, mean fire severity 

was found to increase by 42 percent in the spring, 95 

percent in the summer (June-Aug), and 30 percent 

in the autumn (Sept-Nov). The preliminary results 

from this study suggest that climate change will have a 

significant influence on fire weather and severity in the 

North Okanagan. Increased fire season and severity 

could result in larger, more intense, and frequent fires 

that may significantly influence the ability of forest 

managers to maintain a sustainable timber supply 

and conserve biodiversity. An increased fire frequency 

could facilitate the migration of vegetation by creating 

opportunities for fire-tolerant species and limiting the 

regeneration of fire-intolerant species. Understanding 

the potential threat of climate change on fire severity 

can provide incentive for managers to design their 

forest landscapes as “fire-smart” and incorporate the 

impacts of climate change into sustainable forest 

management planning.

Keywords: Fire Severity, Climate Change, Okanagan, 

Sustainable Forest Management

Craig R. Nitschke and John L. Innes, Sustainable 

Forest Management Research Group, Department of 

Forest Resources Management, University of British 

Columbia, 2045-2424 Main Mall, Vancouver, BC, 

Canada V6T 1Z4

Correspondence to: nitschke@interchange.ubc.ca

Ray, Andrea J. 

Linking Climate to 

Multi-purpose Reservoir 

Management in the 

Gunnison Basin 

As in many other areas in the West, the Gunnison 

basin is increasingly sensitive to climate variability 

because new demands for water are being incorporated 

into the system, including in-stream flows for 

ecosystems and recreation. Some of the implications of 

climate variability and change for water management 

in the 21st century are: 

•	 The effects of multi-year droughts, e.g., periods 

of 3-7 years of below average snow water 

equivalent (SWE) and inflows;

•	 The effects of decadal-scale periods in which 

average inflows are below normal, although 

there may be wet years interspersed; 

•	 The potential impact of a long-term decrease 

in Aspinall inflows, due to decreases in 

precipitation and SWE;

•	 The potential impact of an earlier spring peak;

•	 The opportunity to take advantage of forecasting 

interannual climate variability to improve the 

efficiency of reservoir management, both in wet 

and dry years; 

•	 The possibility of adaptive management with 

respect to the effects of climate on water as new 

understanding about the climate of the region 

becomes available.

The combination of increasing climate sensitivity 

and changing polices requires institutions that are able 

to be adaptive to cope with both anticipated changes 

and those which are difficult to predict. Characteristics 

of water management institutions that are likely to 

be able to cope with the changing policy and climate 

regimes will be discussed. Operations in this system 

have been adjusted for many reasons to benefit the 

basin, for example, managers have responded to both 

the flow recommendations for endangered fish and the 

severe drought of 2002 by increasing flexibility and 

finding new ways of operating to benefit a diverse set 

of water uses. Water management institutions in the 

Gunnison basin have significant adaptive capacity to 

respond to both policy changes and climate events, 

and also the capacity to respond to climate forecasts if 

the appropriate forecasts are available. 

Andrea J. Ray, Ph.D., Research Scientist, NOAA/

Climate Diagnostics Center, 325 Broadway, Mailcode 

R/CD, Boulder, CO 80305-3328

http://www.cdc.noaa.gov/people/andrea.ray; 

email: andrea.ray@noaa.gov
146
147

Darius Adams

Department of Forest Resources

Oregon State University

Peavy Hall 210

Corvallis, OR 97331

541-737-5504

darius.adams@oregonstate.edu

Jamie Barbour

PNW Research Station

620 SW Main St., Suite 400

Portland, OR 97205

503-808-2542

jbarbour01@fs.fed.us

Bill Carlson

Carlson Small Power Consultants

13395 Tierra Heights Rd.

Redding, CA 96003

530-945-8876

cspc@shasta.com

Dave Cox

Mason, Bruce and Girard

707 SW Washington Ave., Suite 1300

Portland, OR 9705

503-224-3445

dcox@masonbruce.com

Matt Delaney

Delaney Forestry Services

1216 Calapooia St.

Albany, OR 97321

541-967-0576

mdelaney1@qwest.net

Speakers

Angus Duncan

Bonneville Environmental Foundation

133 SW Second Ave., Suite 410

Portland, OR 97204

503-248-1905

angusduncan@b-e-f.org

Courtney Flint

Department of Natural Resources and

Environmental Sciences

W-503 Turner Hall

1102 S. Goodwin

University of Illinois

Urbana, IL 61802

217-333-2770

courtflint@yahoo.com

Benjamin Harding

Hydrosphere Consulting

1002 Walnut Suite 200

Boulder, CO 80304

303-443-7839

blh@hydrosphere.com

Richard Haynes

PNW Research Station

620 SW Main St., Suite 400

Portland, OR 97205

503-808-2002

rhaynes@fs.fed.us

Pete Holmberg

Washington Dept of Natural Resources

PO Box 47016

Olympia, WA 98504

360-902-1348

pete.holmberg@wadnr.gov
148

Linda Joyce

Rocky Mountain Research Station

240 W Prospect Ave

Ft. Collins, CO 80526

970-498-2560

ljoyce@fs.fed.us

Gary Lettman

OR Dept of Forestry

2600 State St.

Salem, OR 97310

503-945-7200

glettman@odf.state.or.us

Jesse Logan

Rocky Mountain Research Station

860 North 1200 East

Logan, UT 84321

435-755-3573

jlogan@fs.fed.us

Steve Malloch

Attorney

10212 Belgrove Ct. NW

Seattle, WA 98177

206-818-0482

smalloch@comcast.net

Kyle Martin

Columbia River Inter-Tribal Fish Commission

729 NE Oregon, Suite 200

Portland, OR 97232

503-238-0667

mark@critfc.org

Jack Morgan

USDA Agricultural Research Service

Crops Research Lab 

1701 Centre Avenue

Fort Collins, CO 80526

970-492-7121

jack.morgan@ars.usda.gov

Phil Mote

Center for Science in the Earth System (CSES)

Joint Institute for the Study of the Atmosphere and 

Ocean (JISAO)

University of Washington

PO Box 354235

Seattle, WA 98195

206-616-5346

philip@atmos.washington.edu

Ron Neilson

PNW Research Station

3200 Jefferson Way

Corvallis, OR 97331

541-750-7303

neilson@fs.fed.us

Michael Pellant

Bureau of Land Management

1387 S. Vinnell Way

Boise, ID 83709

208-373-3823

Mike_Pellant@blm.gov

Kelly Redmond

Western Regional Climate Center

2215 Raggio Pkwy

Reno, NV 89512

775-674-7011

krwrcc@dri.edu

Gordon Reeves

PNW Research Station

3200 Jefferson Way

Corvallis, OR 97331

541-750-7314

greeves@fs.fed.us

Randall Rosenberger

Department of Forest Resources

Oregon State University

109 Peavy Hall

Corvallis, OR 97331

541-737-4425

r.rosenberger@oregonstate.edu
149

Stephen Saunders

Rocky Mountain Climate Organization

PO Box 270444

Louisville, CO 80027

303-880-4598

saunders@rockymountainclimate.org

Joel Smith

Stratus Consulting

PO Box 4059

Boulder, CO 80306

303-381-8218

jsmith@stratusconsulting.com

Jim Stevens

The Campbell Group

One SW Columbia, Suite 1700

Portland, OR 97258

503-275-9675

John Townsley

USDA Forest Service

1240 South Second

Okanogan, WA 98840

509-826-3568

jtownsley@fs.fed.us

Lewis Ziska

USDA Agricultural Research Service

10300 Baltimore Ave.

Bldg 46A Barc West

Beltsville, MD 20705

301-504-6639 

lziska@asrr.arsusda.gov
150

Metric Equivalents

When you know: Multiply by: To find:

Inches (in) 2.54 Centimeters

Feet (ft) .3048 Meters

Miles 1.609 Kilometers (km)

Acres (ac) .41 Hectares

Degrees Fahrenheit (°F) (F-32)/1.8 Degrees Celsius (°C)

English Equivalents

When you know: Multiply by: To find:

Centimeters (cm) .394 Inches (in)

Meters (m) 3.28 Feet (ft)

Kilometers (km) .6215 Miles (mi)

Hectares (ha) 2.47 Acres 

Degrees Celsius (°C) 1.8 C + 32 Degrees Fahrenheit (°F) 
Technical Coordinators:

Linda Joyce, Research Project Leader, Sustaining Alpine and Forest Ecosystems under Atmospheric and 

Terrestrial Disturbances, USDA Forest Service, Rocky Mountain Research Station; 240 West Prospect, 

Fort Collins, CO 80526

Richard Haynes, Program Manager, USDA Forest Service, Pacific Northwest Research Station, 

620 SW Main St., Suite 400, Portland, OR 97205

Rachel White, Science Writer-Editor, USDA Forest Service, Pacific Northwest Research Station, 

620 SW Main St., Suite 400, Portland, OR 97205

R. James Barbour, Program Manager, USDA Forest Service, Pacific Northwest Research Station, 

620 SW Main St., Suite 400, Portland, OR 97205

Cover images: Tom Iraci, USDA Forest Service and Olympic National Park

Graphic designer: Erik Ackerson, Portland, OR 97202

Papers were provided by the authors in camera-ready form for printing. Authors are responsible for the content and accuracy. 

Opinions expressed may not necessarily reflect the position of the U.S. Department of Agriculture.

The use of trade or firm names is for information only and does not imply endorsement by the U.S. Department of Agriculture 

of any product or service.

The Forest Service of the U.S. Department of Agriculture is dedicated to the principle of 

multiple use management of the Nation’s forest resources for sustained yields of wood, water,

 forage, wildlife, and recreation. Through forestry research, cooperation with the States and 

private forest owners, and management of the national forest and national grasslands, it strives

—as directed by Congress—to provide increasingly greater service to a growing Nation.

The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and 

activities on the basis of race, color, national origin, age, disability, and where applicable, sex, 

marital status, familial status, parental status, religion, sexual orientation, genetic information, 

political beliefs, reprisal, or because all or part of an individual’s income is derived from any 

public assistance program. (Not all prohibited bases apply to all programs.) Persons with 

disabilities who require alternative means for communication of program information (Braille, 

large print, audiotape, etc.) should contact USDA’s TARGET Center at (202) 720-2600 (voice 

and TDD). To file a complaint of discrimination, write to USDA, Director, Office of Civil 

Rights, 1400 Independence Avenue, S.W., Washington, D.C. 20250-9410, or call (800) 795-

3272 (voice) or (202) 720-6382 (TDD). USDA is an equal opportunity provider and employer.

Pacific Northwest Research Station

Web site http://www.fs.fed.us/pnw

Telephone (503) 808-2592

Publication requests (503) 808-2138

FAX (503) 808-2130

E-mail pnw_pnwpubs@fs.fed.us

Mailing address Publications Distribution

Pacific Northwest Research Station

P.O. Box 3890

Portland, OR 97208-3890

BCCNRM_Cover.indd 2 2/2/07 12:04:51 PM