Geosciences: The Future

Final Report of the IUGG Working Group Geosciences: The FutureGeosciences: The Future

S. Adlen, IAMAS
Atmospheric, Oceanic and Planetary Physics
Clarendon Laboratory
Parks Road
Oxford OX1 3PU(sadlen@atm.ox.ac.uk)

E. E. Brodsky, IAVCEI, Chair
Dept. of Earth and Space Science
University of California, Los Angeles
Los Angeles, CA, USA(brodsky@ess.ucla.edu)

T. Oki, IAHS
Research Institute for Humanity and Nature
Kyoto 602-0878, Japan(oki@chikyu.ac.jp)

A.J. Ridley, IAGA, Editor
Center for Space Environment Modeling
University of Michigan
Ann Arbor, MI, USA(ridley@umich.edu)

L. Sánchez, IAG
Instituto Geografico Agustin Codazzi
Division de Geodesia
Bogota - Colombia(lsanchez@igac.gov.co)

K. Yoshizawa, IASPEIDivision of Earth and Planetary Sciences
Graduate School of Science, Hokkaido University
Sapporo, 060-0810, Japan(kazu@ep.sci.hokudai.ac.jp)

C. Simionato, IAPSO
Centro de Investigaciones del Mar y la Atm ósfera(CIMA/CONICET-UBA)
Dpto. de Ciencias de la Atmósfera y los Océanosde la Universidad de Buenos Aires
Ciudad Universitaria Pab. II Piso 2
Ciudad Autónoma de Buenos Aires - Argentina(claudias@at.fcen.uba.ar)

U. Shamir, IUGG Vice President, WG Coordinator
Stephen and Nancy Grand Water Research InstituteTechnion - Israel Institute of Technology
Haifa 32000, Israel(shamir@tx.technion.ac.il)

July 7, 2003

Preface”IUGG is a purely scientific organisation established to promote and co-ordinate studies of physical, chemical, and mathematical properties of the Earth and its environment in space. These studies include the shape of the Earth; the nature of its
gravitational and magnetic fields; the dynamics of the Earth as a whole and of its component parts; the Earth’s internal structure,composition, and tectonics; the generation of magmas; volcanism and rock formation; the hydrological cycle, including snow
and ice; the physics and chemistry of the oceans; the atmosphere, ionosphere, magnetosphere and solar-terrestrial relations;and analogous problems associated with the Moon and other planets. IUGG activities embrace studies of the Earth by artificial
satellites and other techniques for deploying instruments at high altitude.” (Objectives and Activities of IUGG, in the IUGG
2003 Yearbook)In summer 2001, the Executive Committee of IUGG (Bureau, Presidents and Secretaries General of the seven Associations)approved a proposal I put forward, to set up a Working Group of young geo-scientists, one from each of the seven Associations,
under the title ”Geosciences: The Future” (WG-GTF), to examine the state of the geosciences and identify research challenges,
emphasizing inter-disciplinary research, integration of scientists from around the world, in particular in less developed nations,and the role that IUGG should play in advancing the geosciences into the future.
The Executive Committee of IUGG, acting as Program Committee for the 2003 IUGG General Assembly in Sapporo, also accepted the proposal to include in the program Union Symposium U8: ”Geosciences: The Future,” to be prepared and presented
by the Working Group.
The WG-GTF, after preliminary discussion and consideration of its expected role and mode of operation, chose its Chair
and Editor. Each member prepared a presentation of her/his discipline/Association, sometimes based on material producedby similar initiatives of the Association and/or on responses elicited from other members of their Association. These were
circulated among the members, and were discussed in extended conference-calls. Special emphasis was placed on identifying
common and inter-disciplinary interests and on encompassing scientists from all parts of the world.
This publication comprises the material prepared by the WG-GTF ahead of the IUGG GA 2003 in Sapporo.
Uri Shamir
IUGG Vice President
Coordinator of the WG-GTF

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Contents
1 Introduction

9E. E. Brodsky

2 International Association of Seismology and Physics of the Earth’s Interior
K. Yoshizawa

2.1
2.2
2.3

2.4
2.5
2.6
2.7
2.8

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Long-term Goals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Short-term Priorities: Issues and Strategies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.3.1 Seismic Observation and Data Acquisition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.3.2 Physics of the Earth’s Interior: Structure, Composition and Dynamics . . . . . . . . . . . . . . . . . .
2.3.3 Physics of Earthquakes and Seismic Wave Field . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.3.4 Hazard Mitigation and Prediction of Earthquakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Recommendations for Seismology and Physics of Earth’s Interior . . . . . . . . . . . . . . . . . . . . . . . .
Seismological Researches and Societal Benefit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Opportunities for Interdisciplinary Researches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Acknowledgment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3 International Association of Volcanology and Chemistry of the Earth’s Interior
E. E. Brodsky

3.1
3.2

3.3

3.4

3.5
3.6
3.7

Long-term goals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Short-Term Priorities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.2.1 Initiation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.2.2 Explosive/effusive transition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.2.3 Eruptive Plumes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.2.4 Climatic effects of eruptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.2.5 Flow Emplacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.2.6 Interactions with Tectonics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.2.7 Magma Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.2.8 Conduit Transport . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Recommendations for Volcanology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.3.1 Observations and Modeling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.3.2 Instrumentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Recommendations for IAVCEI and IUGG . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.4.1 Travel for Observatory Scientists . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.4.2 WOVOdat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.4.3 Communicating with Society . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Opportunities for Interdisciplinary Research . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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4 International Association of the Physical Sciences of the Oceans
C. Simionato

4.1
4.2
4.3
4.4
4.5
4.6
4.7

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A view of the future of research in Physical Oceanography . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Long-term goals for Physical Oceanography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Short term focus for Physical Oceanography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.4.1 Climate and climate change prediction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.4.2 Coastal oceans prediction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5 International Association of Hydrological Sciences
T. Oki

5.1
5.2
5.3

5.4
5.5

5.6

Introduction —Hydrology, the forgotten earth science— . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Long-term Goals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.2.1 What is hydrology? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.2.2 Long-term Goals in Hydrology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Short-term Goals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.3.1 Current Demands on Hydrology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.3.2 Contribution to solve the world water crisis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.3.3 IAHS Hydrology 2020 Working Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.3.4 Scientific Bottlenecks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.4.1 Organizational Issue . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.4.2 Practical/Technological Issues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Social Benefits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.5.1 Science as part of capacity building and governance . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.5.2 Bridging the communication gap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.5.3 Develop a scientifically based policy language . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.5.4 Recommendations for future actions – filling the gaps . . . . . . . . . . . . . . . . . . . . . . . . . .
Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6 International Association of Geodesy
L. Sánchez

6.1
6.2

6.3

6.4
6.5
6.6

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A view of the future of research in Geodesy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.2.1 Long term focus for Geodesy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.2.2 Short term focus for Geodesy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Assessment of current research in the major geodetic disciplines . . . . . . . . . . . . . . . . . . . . . . . . .
6.3.1 Reference Frames . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.3.2 Gravity Field . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.3.3 Earth Rotation and Geodynamics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.3.4 Positioning and Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.3.5 Theory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Opportunities for interdisciplinary research . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7 International Association of Meteorological and Atmospheric Sciences
S. Adlen

7.1
7.2
7.3

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Long Term Goals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Short Term Priorities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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7.4
7.5

7.3.1 Atmospheric Chemistry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7.3.2 Climate and Climate Change . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7.3.3 Atmospheric Dynamics and Meteorology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7.3.4 Planetary Atmospheres . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Recommendations for the Atmospheric Sciences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8 International Association of Geomagnetism and Aeronomy
A. J. Ridley

8.1

8.2

8.3
8.4
8.5

Long-term Goals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.1.1 Focus Areas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Short-Term Priorities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.2.1 Thermosphere and Ionosphere . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.2.2 Magnetosphere . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.2.3 The Sun and the Heliosphere . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.2.4 Ground-based Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Recommendations for the IAGA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

9 Interdisciplinary Research
S. Adlen

9.1
9.2

9.3

9.4

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Over arching Opportunities for Inter-disciplinary Research . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.1 Planetary Exploration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.2 Mathematical Techniques . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.3 Observing Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.4 Communication and the Availability of Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.5 High Resolution Earth System Modeling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.6 Looking to the Future . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Other Opportunities for Interdisciplinary Collaborations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.3.1 The Hydrologic Cycle (IAMAS, IAPSO and IAHS) . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.3.2 The Role of Geodetic Sensing in Interdisciplinary Earth Science (IAG and Others) . . . . . . . . . . .
9.3.3 The Interaction of the Thermosphere, Upper Atmosphere and Solar Forcing (IAGA and IAMAS) . . .
9.3.4 Climate Response to SO2 Aerosol Forcing (IAVCEI, IAMAS) . . . . . . . . . . . . . . . . . . . . . .
9.3.5 Generation and Propagation of Tsunami (IASPEI, IAPSO) . . . . . . . . . . . . . . . . . . . . . . . .
9.3.6 Seismology for the Earth and the Sun (IASPEI, IAGA) . . . . . . . . . . . . . . . . . . . . . . . . . .
9.3.7 Water, Earthquakes and Volcanoes (IAHS, IASPEI, IAVCEI) . . . . . . . . . . . . . . . . . . . . . .
9.3.8 Interactions with Disciplines Outside Geoscience . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Conclusions and Recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

10 Societal Impact
K. Yoshizawa

10.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10.2 Geophysical Risks: Prevention of Natural Hazards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10.2.1 Interactions Between Community and Geosciences . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10.2.2 Effective Use of Technology and Scientific Results . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10.2.3 Some Counter-measures Against Gigantic Natural Hazards . . . . . . . . . . . . . . . . . . . . . . . .
10.2.4 The Role of the IUGG . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10.3 Human Life and Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10.3.1 Global Change and Human Activity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10.3.2 Management of Water . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10.3.3 Improvement of Quality of Life . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10.3.4 The Role of IUGG . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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10.4 Geoscience Education and Outreach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
10.4.1 Efficient Use of Modern Technology for Scientific Education . . . . . . . . . . . . . . . . . . . . . . . 99
10.4.2 Promoting International Schools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
10.4.3 Communication with Society . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
10.4.4 International Assistance to Developing Countries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
10.5 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
10.6 Acknowledgment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
11 Developing Countries

L. Sánchez
101
11.1 Natural and energetic resources provision . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
11.2 Observing data world-wide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
11.3 Strategic positions to analyse concrete phenomena . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
11.4 Importance of geosciences in the modern society, and especially in developing countries . . . . . . . . . . . . 102
11.5 Vulnerability to natural disasters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
11.6 Sustainable development . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
11.7 Transferring technology and improving scientific level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
11.8 The role of developing countries in geosciences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
11.9 Scientific cooperation beyond political and economical denominations . . . . . . . . . . . . . . . . . . . . . . 103
11.10Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104

12 Conclusions

105

E. E. Brodsky

8Chapter 1

Introduction
E. E. Brodsky

It is both the tradition and responsibility of geoscience tohelp humanity. Seismologists and volcanologists attempt tosave lives by evacuating before eruptions or mitigating theeffects of earthquakes. Geodesists quantify the shape of the
Earth so that cities can be built and airplanes flown. Space
physicists provide a window into the nearly unknown worldin which our satellites are sent and spacecraft launched. Hydrologists, oceanographers and atmospheric scientists may
have the heaviest burden of all as they help guide the planet
through the current climate crisis.

The overall conclusions of the report provide a concise summary of our recommendations for geoscientists in general and
IUGG specifically.
This report would not have been possible without the assistance of numerous colleagues who gave generously of theirtime and insights. As young geoscientists, we had to combine our new point of view with an already extensive base ofknowledge and planning in the field. This report is a hybrid of
our enthusiastic dreaming and the somewhat more grounded
reality of many reviewers, advisers and colleagues. Perhaps
together we can see the future.

Geoscience also has the responsibility to not confine itself
to addressing current problems. As a science, we must develop a framework to address future issues. In order to pushknowledge forward, we must invest intellectually and financially in basic science at a level commensurate with the applied fields. Such an investment is intrinsically risky. Many
scientific leads turn out to be dead-ends. Other pathways may
continue indefinitely, but are difficult to connect to the rest of
the field. A field driven by pure thirst for knowledge runs
the danger of becoming a tangled spider web of seemingly
unrelated facts and personal theories.
Basic science needs to be guided by a long-range vision of
the future of the field. Then geoscientists can advance knowledge in a focused way and real progress can be made. The
purpose of this report is to present a particular vision that
could guide research in the major fields of geophysics andgeodesy. This vision is articulated by a young generation ofgeoscientists with a stake in the future. Together, we havecompiled a view encompassing geosciences from the studyof the Earth’s core to the workings of the Sun.
The main body of this report is organized into chapters representing the domain of each of the associations of IUGG inorder from the center of the Earth. Each chapter discusses
a long-term vision for the field for the next 50–100 years
as well as short-term goals and strategies for achievement.
Cross-societal chapters follow the disciplinary section. They
outline important directions for interdisciplinary studies, societal benefits and projects targeting less developed countries.
910Chapter 2

International Association of Seismology andPhysics of the Earth’s Interior
K. Yoshizawa

2.1 Introduction

because we need a variety of information from diverse disciplines, such as seismology, mineral physics, geodynamics
and geochemistry, in order to better understand the inaccessible parts of the Earth. In the future, more comprehensive interdisciplinary researches on the close interactions with otherparts of the Earth, i.e., oceans and atmosphere, will be inevitable.
Scientific studies of earthquakes are critical to people wholive in seismically active areas. The possibility of a shortterm prediction of earthquakes is still a controversial issue
in seismology. However, the quest for the development ofpractical methods to predict earthquakes in both the long andthe short term, as well as to mitigate catastrophic damages, isessential to reduce threats of earthquakes on our society.
In seismology, a larger class of earthquake phenomenology
is still not understandable within the present framework ofknowledge, such as the dynamic rupture processes of earthquake faults, high-frequency behaviour of seismic waves in
3-D structures, and the physics of deep-focus earthquakes.
Tackling such unsolved problems will require a long-term efforts to develop systematic theories complemented by geophysical observations and laboratory experiments. The accumulation of seismic data over a long period of time will
enable us to propose, test and modify hypotheses related toearthquakes and physics of the Earth’s interior.
To extend our knowledge on the Earth as a system, including earthquakes, volcanic activities, water circulation, etc.,
integration of all the available information on the dynamics
of the Earth should be pursued.

The primary objectives of IASPEI (International Associationof Seismology and Physics of the Earth’s Interior) are to promote scientific studies related to earthquakes and physicalproperties of the Earth’s interior, and to facilitate international
research and education programs in seismology and physics
of the Earth’s interior. IASPEI has placed major research emphasis on understanding the nature of earthquakes, the propagation of seismic waves, the physical makeup and dynamics of the Earth’s interior, and reducing catastrophic damages
caused by large earthquakes.
In this chapter, future research under the umbrella of
IASPEI are summarised. We first look at long-term goals forthe future development of geosciences relevant to IASPEI.
Subsequently, we summarise new challenging topics of existing disciplines covered by IASPEI, which should be tackled
in the coming decade, followed by some recommendations
for IASPEI and opportunities for interdisciplinary research.
A summary of current research programs of IASPEI has
been given in a brochure which is available from an official web site (http://www.iaspei.org/brochure/brochure.html).
A comprehensive summary of the development in earthquake and engineering seismology during the last century
has been published in International Handbook of Earthquake
and Engineering Seismology (Lee et al., 2002, 2003). The
practice of observational seismology has been summarisedin IASPEI Manual of Seismological Observatory Practice(http://www.seismo.com/msop/msop intro.html).

Towards an Integrated Earth Model

2.2 Long-term Goals

In order to provide a better understanding of the dynamics
of the Earth’s interior, a variety of information from a wide
range of disciplines (e.g., seismology, mineral physics andother geophysical sciences) is necessary.

The IASPEI has facilitated researches in understanding physical phenomena taking place in the solid Earth. The studyof the Earth’s interior is a naturally multidisciplinary subject
11

Seismic waves are one of the most reliable and optimum
tools for probing the Earth’s interior. They have been utilised
not only to investigate the whole Earth structure, but also to
explore the natural resources. Of all geophysical methods,
seismological investigation provides us with the highest resolution of the inside of the Earth, and thus the development ofseismology will, in turn, be the basis to promote the development of solid Earth geophysics.
Combining all available information, such as seismic structure, surface deformation, plate tectonics, numerical resultsof mantle convection, heat transfer and material circulationin the Earth, we will be able to create a dynamic model ofthe Earth’s interior including both physical and chemical processes in the Earth. In order to interpret the seismic modelsof the Earth, contribution from other geophysical disciplines,
such as mineral physics, geodynamics and geochemistry, arenecessary. Furthermore, in the future of geosciences, creatinga systematic Earth model, taking account of the interactions
between atmosphere, oceans and the solid Earth, will be an
ultimate goal to understanding the Earth as a dynamic system.

bility of gaining information on planetary interiors without shaking sources in their inside; i.e., it may lead to abasis of the exploration of other planets where there may
be no seismic activity but still some atmospheric interaction. Theoretical studies to uncover the mechanismsof the background free oscillations will be essential for
applications to planetary exploration.
Planetary Seismology: We can gain many sorts of information on the Earth’s interior, but we know very little about
the interior of other planets. There are some seismic datafrom the Moon, and we can deduce a very rough imageof its inside, but it is not as clear as what we know about
the Earth due to the lack of seismic data. Other planets
have been unreachable to seismologists so far, and what
we can get is only a rough estimate of their density distribution, which can be estimated from the moment ofinertia and mass.
Several projects to explore the Moon and the planet Marsare being conducted. The Japanese LUNAR-A project(Institute of Space and Astronomical Sciences of Japan)
will launch seismometers and thermometers using penetrators to study the interior of the Moon, especially
focusing on the investigation of the existence of the
Moon’s iron core. An European and American consortium planned the NetLander mission to bring seismometers to Mars to investigate the Martian interior with a
special focus on the existence of buried water and ice,
although the mission ran aground due to the withdrawalof two major participating nations.

Water in the Earth: The role of liquid water can be a key
to combining the diverse fields of studies related to the
Earth’s interior, as well as the outer shells of the Earth:ocean and atmosphere. From a perspective of the solid
Earth geophysics, it will be most interesting to investigate the presence of liquid water, and its physical andchemical roles in dynamics of the Earth. Recent studies with high-resolution seismic tomography suggest theexistence of fluids in fault areas (e.g., Zhao et al., 1996).
Further investigation of the role of water in the occurrence of earthquakes will be important for quantitative
studies on earthquake mechanisms. Water may also play
an important role in the internal dynamics of the Earth,since it has been recognised that a number of mantle
minerals are capable of sequestering significant amountsof water in hydrous phases.

Through such efforts to bring seismic instruments to theother planets, we will be able to get more concrete information on the deep structure of other terrestrial planets, which will be of great help to better understand theformation and evolution of our planet. A novel technology to bring high-resolution instruments to other planetsat a reasonable cost will be useful for the developmentof planetary seismology. Furthermore, international cooperation and partnership will be essential to make themissions of planetary exploration feasible and successful.

Coupling Between the Solid Earth, Atmosphere, Ocean: In
the late 1990s, we witnessed exciting new findings
about the Earth’s continuous tremors even without
earthquakes; i.e., the background free oscillations(e.g., Suda et al., 1998; Kobayashi and Nishida, 1998),
which have been derived from high quality observations
with broad-band seismometers and superconducting
gravimeters (Fig 2.1). The cause of this phenomenon isstill in the centre of debate, but it is likely to be related
deeply to interactions with the Earth’s atmosphere
and/or oceans. Such interactions of fluid and solid
systems will be of significant importance in the coming
decade.

2.3 Short-term Priorities: Issues andStrategies
2.3.1

Seismic Observation and Data Acquisition

Unlike the atmosphere and oceans that cover the solid part of
the Earth, the Earth’s interior is invisible and untouchable. Information on the inside of the Earth can only be derived fromobservations near the Earth’s surface. Seismic stations playa role as a “telescope” to look into the Earth and provide us

The fact that the Earth is vibrating due to interactions
with Earth’s fluid layers gives us an insight into a possi12

Figure 2.1: A spectrogram for a period between 1998 and 1999 observed at BFO station of IRIS/IDA network showing the
Earth’s background free oscillations. Labels on the bottom indicate eigenfrequencies of fundamental spheroidal modes, andthose on the top indicate angular orders of the modes. A histogram on the right displays seismic moments (Nm) in a logarithmic
scale, which indicates the occurrence of large earthquakes during the period of observation. Large amplitude spectra are shownin blue; i.e., the horizontal blue tracks represent prominent amplitudes caused by large earthquakes. We can see vertical traces
throughout the period of observation, even on “quiet” days, with no earthquakes (yellowish area), which are extremely wellcorrelated with the angular orders of spheroidal free oscillations. These vertical traces indicate the existence of background freeoscillations of the Earth, which are caused by some other sources than earthquakes [courtesy of N. Suda].

13

with precious information about physical processes of Earthquakes, as well as the structure of the solid Earth. For future
development of the studies of earthquakes and Earth’s interior, continuous efforts to expand the seismograph network,at both global and regional scales and with high-quality instruments, are essential.

extended experiment modeled on the S KIPPY philosophy, theUSArray, is being conducted (e.g., Levander et al., 1999).
The USArray is now a part of the EarthScope project(United States), which includes SAFOD (San Andreas Fault
Observatory at Depth), PBO (Plate Boundary Observatory)and InSAR (Interferometric Synthetic Aperture Radar) as
well as the USArray to unveil the structure and evolutionof the North American continent. The USArray proposes tocover the continental United States with a set of transportablenetworks of around 400 broad-band seismometers over ten
years. The experiment will resemble a window blind pulled
across the country with about 400 instruments deployed at atime, with a process of redeployment to the farther side after
about 18 months in place. Thus, around 2000 stations in total
are expected to cover the entire United States. The USArray will enable us to reveal the seismic structure of the North
American Continent at an unprecedented resolution. Further
developments of this type are to be expected for other continents.

Enhancing Global Coverage of Seismograph Network
Currently, over 120 permanent seismic stations affiliated to
FDSN (Federation of Digital Broad-Band Seismic Network)
are operated all around the globe, which make it possible toreveal a large-scale (∼ 1000 km) 3-D image of the Earth’s
inside. Even so, the distribution of such seismic stations is
far from uniform, and some regions, such as most parts of
the oceans, are yet to be covered. It is critical to achieve uniform distribution of seismic stations with uniform seismometer characteristics to make observations of all signals of seismic phases that pass through the Earth’s interior.
Regional High-Density Seismic Array

Ocean Bottom Network

To obtain a better resolution for 3-D Earth models, we needseismic data from dense seismic arrays with a concentrationof seismometers in a small region. The recent deploymentsof high density seismic arrays by a Japanese Agency, NIED
(National Research Institute for Earth Science and Disaster
Prevention), is an ideal example; the whole Japanese islands
are covered with 1000 high-sensitivity seismometers at 20 km
spacing. This is an unprecedented experiment of very highdensity seismic network, providing an enormous amount ofrecords. The data sets derived from the array are beginning
to provide us with evidences of interesting phenomena inside the Earth. For example, we can “see” subtle movementof fluid in the lithosphere that is away from active volcanic
fronts; i.e., it may be the first seismic evidence of the dehydration processes of subducting slabs in the mantle (Obara,
2002).
The deployment of such very high-density seismic arrays,
starting with the tectonically active regions, will be of great
importance in the progress of the solid Earth sciences in the
coming decade.

Seismic observations at the ocean bottom, which covers 70%of the Earth’s surface, are critical to achieve uniform coverageof seismograph stations over the globe. Several projects to
install seismometers at the ocean bottom are currently being
undertaken, e.g., Ocean Hemisphere Project (University ofTokyo) and International Ocean Network. Continuous efforts
to enhance such ocean bottom seismograph networks are required. There are efforts underway to develop disposable autonomous floating devices equipped with hydrophones in order to improve data collection in inaccessible regions without
the human cost or ship time required to deploy and retrieve
ocean bottom instruments (Simons et al., 2003). Moreover,
up to now, there has been no means to measure deformationof the Earth’s surface at the ocean bottom. Exploring seafloor
deformation at GPS-level resolution will provide valuable information about dynamic processes of the Earth.

Interpretation and Analysis of Seismic Data
The enhancement of seismological interpretation and analysis will provide better data sets, such as better seismic event
locations, better event catalogues, and more accurate and richtravel timetables of seismic phases, for further seismological researches. Also, physical parameters describing earthquake sources, such as radiated energy, seismic moment tensor, stress drop, rupture length, slip amount and slipping history, can be provided by seismological observation and interpretation on routine basis. Dissemination of such enhanced
data sets will be an important contribution for a better understanding of earthquakes and physics of the Earth’s interior.

Continent Probing with Portable Seismic Arrays
In seismically inactive areas, like the middle of most continents, it seems rather impractical to make a permanent installation of a high-density seismic array. However, such anarray is essential to probe into the Earth. One of the mostsuccessful field experiments of deployment of portable seismic arrays at a continental scale has been conducted in Australia throughout the 1990’s, (the S KIPPY Project – van der
Hilst et al., 1994). Following its great success in producing
high-resolution seismic models in the Australasian region, an
14

2.3.2

Physics of the Earth’s Interior: Structure, Composition and Dynamics

Material Properties of the Earth’s Interior
Physical Properties of Earth Materials and Seismic Models:
What causes the lateral heterogeneity of seismic wave
speed in the mantle? What is the role of water in thecrust and mantle? Revealing rheological behaviour of
the Earth materials is required to understand the natureof dynamic phenomena in the Earth, such as upwelling
plumes, subducting plates, continental lithosphere,
lithosphere-asthenosphere transition, etc. It is also important to address the relationship between wave speed
anomaly, density anomaly and anelastic attenuation of
the Earth’s constituents working with in-situ laboratory
experiments (e.g., Jackson, 2000).

Seismology and related disciplines provide a means of looking into the inside of the Earth where dynamic activities on
the geological time-scale are taking place. Our knowledgeof the internal structure and dynamics of the Earth has advanced significantly in the last a few decades. This is mainly
due to developments and advances in rapidly growing seismic networks, computer simulations of mantle convection
and laboratory-based experiments on the physical propertiesof constituents of the Earth. This section focuses on future research topics that are expected and are necessary to be tackled
in the coming decade for further understanding of the natureof the Earth’s interior.

Anisotropy and Dynamics of the Earth’s Interior: There are
a number of observations that suggest the existence ofanisotropy in the crust and upper mantle (e.g., Parkand Levin, 2002). The determination of the scaleof anisotropy from seismic data is not simple because of trade-off between wave speed and anisotropy.
Anisotropy of the Earth materials is likely to have a close
relation with the current and historical dynamics of the
Earth. Therefore, the study of the anisotropy in the Earthcan be a clue to understand the convection processes ofthe mantle.

3-D Imaging of the Earth’s Interior
Construction of 3-D Reference Earth Model: Extended seismograph networks have enabled us to delineate threedimensional distribution of heterogeneity in the Earth.
We now have plenty of seismic information that should
be useful for constructing a three-dimensional Reference
Earth Model, including large scale lateral heterogeneity
in the Earth’s mantle (∼ 1000 km), which will be a substitute for conventional 1-D Reference Earth Models. In
addition, creating a high-resolution (less than 100 km
scale) reference crustal model will be crucial to enhance
the resolution of regional tomography models. The information of an on-going project of creating a Reference
Earth Model is available through a web site at UC San
Diego (http://mahi.ucsd.edu/Gabi/rem.html).

Dynamic Processes of the Earth’s Interior
Integrated Earth Models: It is critical to understand largeand small-scale phenomena in the context of plate tectonics, convection processes, and Earth’s rheology andmaterial constitution. In this regard, studies of mantle
convection and its effects on surface topography, plate
tectonics, physical and chemical processes, and thermal
sources in the mantle and core will be essential. Also,
measurements of surface deformation, strain field andits variation by various geophysical approaches will provide useful constraints on the geodynamical models.

Extending Seismic Tomography: The development of techniques for seismic tomography has brought a significant
jump in our understanding of the Earth’s interior, despite its relatively simple techniques mostly based on
ray theory. Recently, many efforts have been made toobtain more precise and accurate images of the Earth’s
interior, taking account of much more complicated effects of seismic wave propagation, such as scattering anddiffraction at finite frequency of seismic waves (Dahlen
et al., 2000; Yoshizawa and Kennett, 2002). Such new
approaches to seismic tomography require a significant
amount of computation compared to the conventional
ray theoretical methods, but will be applicable to largescale inversion with the development of high-power
computing facilities. Moreover, with powerful computers, a fully non-linear inversion, employing a global optimization method, can be applied to large-scale inverse
problems. The evaluation of the ensemble of models derived from such direct non-linear inversions (e.g., Sambridge, 1999) will also be useful to validate 3-D Earthmodels.

Seismic/Geophysical Discontinuities in the Earth: It is important to unveil the physical and chemical propertiesof seismic/geophysical discontinuities within the Earth,which play important roles in dynamic processes in the
Earth. For example, Mantle Transition Zone (410 - 660
km depth), in which phase transformations in mantle
minerals occur, plays a critical role in controlling thematerial circulation in the mantle. The existence of Ultra Low Velocity Zone (ULVZ) at the base of the mantle
is suggested by many of recent researches. Further investigation of the role of CMB and D” and inner-coreboundary are also important (see below).
Physics and Chemistry at the Core-Mantle Boundary (CMB):Of all the boundary layers in the Earth, the Core-Mantle
Boundary and the D” layer are the least known, but a15

key region to understanding the thermal and dynamicalsystems of the Earth’s mantle. It should be clarified
what causes the strong heterogeneity in the D” layer,
and what is a real figure of the upwelling plumes; alarge-scale super plume or a cluster of small-scale
plumes? Dense broad-band three-component seismicarrays will be a key to revealing the actual makeup of theD” (e.g., Kendall, 2000). Linking the high-resolution
seismic evidences and numerical results of mantle
dynamics will be essential for a better understanding of
the bottom of the mantle.

rials, need to evolve from the microscopic scale to themacroscopic scale. Finding a bridge over such gaps
based on physics is fundamentally important. Many unsolved problems in studies of fault dynamics, including
stress state, dynamic rupture processes and the originof spatio-temporal earthquake complexities, will need tobe addressed in a common framework (e.g., Ben-Zion,
2001).
Role of Fluids in Fault Slip: In order to understand physicaland chemical conditions that may lead to an immediate
earthquake, interactions between fluid and rock will beof importance in the coming decade to understand therole of fluids in the facilitation of fault slip. Quantitativeevaluation of effects of elastohydrodynamic lubricationof faults (Brodsky and Kanamori, 2001) may be a clue
to understand the nature of rupture processes of faults.

Inner-core Rotation and Anisotropy: Is the inner-core rotating with respect to the mantle? The possibility of differential rotation of the inner core with respect to themantle has been one of the topics in the centre of debate
in the studies of Earth’s deep interior. Some researches
suggested that there is observable rotation of around 1
degree/year (Song and Richards, 1996), whilst otherssuggested negligible rotation rate (Laske and Masters,1999). The elucidation of this issue will require longterm observations since the rotation rate seems to be too
small to be adequately resolved without data sets overmany years.

Mechanisms of Deep Focus Earthquakes: There are also a
number of puzzles in the mechanisms of the deep-focus
earthquakes. Phase transition of the Earth’s materials
in the Mantle Transition Zone is likely to be one of thecauses. Recent studies also suggested that dehydration
processes in subducting slabs can be a cause of deepfocus earthquakes (Hacker et al., 2003). Further investigation of the physical and chemical processes, which
may lead to the occurrence of deep-focus earthquakes
should be pursued.

Recent studies also revealed that the inner-core is likely
to have two distinct layers; the uppermost inner-core
may be rather isotropic whereas the innermost innercore may have anisotropic properties (Tromp, 2001). It
should clarified how such a boundary between the innermost and outermost inner-core is formed. Revealing thestate of the inner-core anisotropy is an important factor
to clarify the formation and evolution of the solid core of
the Earth. To obtain a better resolution of seismic models in the deep interior of the Earth, high-density seismicarrays will be of great help.

Modeling the Seismic Wave Field in 3-D Structures
Understanding the nature of seismic waves propagating incomplex 3-D Earth models at both regional and global scales
is indispensable for the progress of researches in seismic
sources, Earth structure, and hazard mitigation. Recent
high-power computing facilities, such as the Earth Simulator(Japan Marine Science and Technology Center), will enable
us to simulate such numerical experiments, including highfrequency seismic waves.
Recent advancement of PC cluster architecture with free
operating systems, such as LINUX, provides an alternative
high power parallel computing facility, which is extremely
economical compared to costly supercomputers, and will be
crucial for the development of computational seismology andgeophysics (Komatitsch et al., 2002) (Fig. 2.2).

Fluid-Solid Interactions: What is the role of water andvolatiles in the dynamics of the solid Earth? How does
water affect plate tectonics, mantle convection and genesis of continents? In this respect, understanding the origin, distribution and the transportation of H 2 O on thesurface and the inside of the Earth is essential. The interactions of the solid Earth with ocean and atmosphereshould also be investigated.

2.3.3

Physics of Earthquakes and Seismic
Wave Field

Scientific Basis for Comprehensive Test Ban Treaty(CTBT)

Physics of Earthquake Sources

Improvements of the capability to identify the natural andman-made seismic events as well as the enhancement of
global seismograph networks are essential to enforce the
CTBT. A more accurate knowledge of 3-D Earth structure
plays an important role in this regard. Global tomographymodels with the extended techniques as well as sophisticatedGeneration of Earthquakes: Studies of the initiation andpropagation of rupture processes at seismic sources are
critical to better understand the physics of earthquakes.
The governing equations for physical and chemical processes of seismic sources, as well as the Earth’s mate16

be caused by possible large earthquakes. Therefore, seismic exploration to reveal detailed seismic structures beneathmetropolitan areas, in conjunction with earthquake engineering, will be a prerequisite for the mitigation of seismic hazards.
Quantitative Evaluation of Earthquake Precursors
Earthquake prediction has been debated for a long time. The
opinions vary from optimism to extreme pessimism. The effort should be continued as long as humans inhabit the tectonically active areas of the Earth. There are some observations that seem to be related to earthquake precursors, but
most of them are specific to particular regions and times, andseem not to be universal phenomena. The effort for finding such pre-earthquake phenomena is important for those regions where we expect high seismic risks. Quantitative evaluations of radio wave anomalies, electromagnetic phenomena, atmospheric precursors, chemical changes of groundwater, etc., in conjunction with physical and chemical propertiesof rocks, will be needed.

Figure 2.2: Snapshots of computer simulation of seismic
waves generated by the June 9, 1994, Bolivia event. Fullwaveform modeling in a 3-D structure with rapidly-growing
computing facilities will be a key to advancing the geosciences [courtesy of J. Tromp].

Early Warning System
In order to minimise damages of disastrous earthquakes tosociety, it is vital to provide information of early warning to
the public immediately after the occurrence of the event. To
achieve this, the quantitative assessment of the first motion ofseismic signal is essential. This type of early warning system
has already been introduced in some countries with high seismic risks, such as Japan, USA and Mexico. Dense permanentseismic networks are required to enable this system be usefulin case of large earthquakes.

event location algorithms (e.g., Nicholson et al., 2002) will
be of importance.

2.3.4

Hazard Mitigation and Prediction ofEarthquakes

Risk Assessment and Hazard Mitigation
Taking precautions against catastrophic natural disasters is a
critical issue for modern society. We should make continuous
efforts to reduce the risks and damage to society. As yet, asystematic approach to accurate predictions for earthquakes
is unavailable. In this regard, it is important to create hazard maps based on a quantitative assessment of the results ofgeophysical surveys in inhabited areas where there are highpotential risks.

2.4 Recommendations for Seismology
and Physics of Earth’s Interior

Simulating Strong Ground Motion

Linkage of Theory, Observation and Modeling:
Theoretical developments in seismology, such aswave propagation in 3-D Earth and the physics ofearthquake sources, need to be merged with the rapidly
growing number of observed data. The methods fromthe latest numerical modeling should play a role as aglue to link the latest theory and observations by helping
interpretation of data and validation of the theory.

The topics and strategies for future research in the frameworkof IASPEI discussed in the previous sections should be integrated to give a self-consistent dynamic model of the Earth,
combining a variety of information sources from a wide rangeof scales in both time and space.

The most devastating damage inflicted by earthquakes is usually caused by strong ground motions near a seismic source.
With improved knowledge about underground structures andthe rupturing pattern of earthquake sources, we can simulate
and assess how the ground will be shaken by incoming seismic waves (e.g., Furumura et al., 2002). Employing computer
simulations of strong ground motion with an appropriate local structural model (e.g., Fig. 2.3), we can predict damage
patterns and take some precautions against hazards that can

Simulating Scenario Disasters: The worst-case scenarios
for earthquakes and tsunami disasters can be evaluated17

Figure 2.3: Snapshots of ground motion for Nankai “scenario” earthquake (Mw 8.0) in south-west Japan, derived from 3-D
parallel simulation using the Earth Simulator. The bottom figure illustrates a 3-D model of the crust and upper mantle used in
the wavefield modeling. Purple zones indicate rupture areas of the fault [courtesy of T. Furumura].
will be important to achieve a better global coverage ofseismic networks by deploying new regional seismicarrays, including ocean bottom instrumentation, as well
as by gathering data from existing regional networks,
which are yet to join the FDSN.

quantitatively by integrating a variety of state-of-theart information and techniques, such as high-resolution
seismic velocity models, the expected mechanism andmagnitude of earthquake sources, sophisticated numerical methods, and high-power computing facilities (Fig2.3). This will be helpful for the creation of seismic andtsunami hazard maps for regions with high risks of suchdisasters.

Fostering International Schools for Young Researchers:
Promoting educational programs for students andyoung researchers is important to fostering international
collaboration amongst young generations. Financial
support for young researchers, especially those fromdeveloping countries, should be broadly available.

Gathering and Dissemination of Seismic Data: Covering
the Earth uniformly with broad-band seismic stations isessential for the construction of high-resolution seismic
models. International organizations, such as the Federation of Digital Broad-Band Seismograph Network(FDSN) and the Incorporated Research Institutionsof Seismology (IRIS), have made efforts to facilitate
circulation of seismic data by gathering data fromregional seismic networks all over the globe. Still, thecurrent coverage of seismic stations is not sufficient. It

International training programs for researchers from developing countries will also be important to educate andtrain scientists, technicians and science teachers in thoseregions. There is a successful example of an international training project, which has been offered by the
Building Research Institute of Japan for more than 40
18

years, for educating professionals and technical experts
in seismology and earthquake engineering from developing countries.

cost will be of significant help in reducing damages indeveloping countries.
Insurance Policy: Disastrous earthquakes in urban area
cause not only large numbers of casualties, but alsohuge economic losses. Insurance policies for the caseof catastrophe should be constructed based on the latest
scientific information.

Promoting International Projects: It will be one of theimportant missions of IASPEI to foster international
collaborative observations and research projects. In
particular, cooperation between developing and developed countries will contribute to both the developmentof global seismology and the development of regional
economy and society in developing countries.

Personal Seismic Monitoring System: It will be useful todisseminate personal sensors and recoding systems thatcan be linked to personal computers, internet, TV, and/or
mobile telephones, as a complement of professional observation facilities. Such personal facilities can play arole as a component of education of the public and outreach for the reduction of natural disasters.

Efficient Use of Internet Resources: The internet provides
us with enormous possibilities for easy and economical communications with colleagues all over the world.
With the advent and spread of the Giga-bit networks, itwill be possible to hold face-to-face international conferences, schools, workshops, and a variety of meetings
through the internet. Free access to geoscientific information through the internet would be of great help in theadvancement of geosciences.

2.6 Opportunities forplinary Researches

Interdisci-

Linking Surface Tectonics and Mantle Dynamics (IAG,
IAVCEI): The deformation of surface topography reflects the dynamic processes that are going on in the
Earth. Continuous geodetic observations of the surface
deformation provide not only useful information for understanding the dynamics of the Earth’s interior, but also
indispensable information on the occurrence of earthquakes and volcanic eruptions.

2.5 Seismological Researches and Societal Benefit
Hazard Maps: It is essential to create hazard maps to evaluate the seismic risk in local areas, based on geologicaland geophysical investigations of active faults and numerical simulations of strong ground motion in a local
seismic structure. Basic researches on crustal deformations and seismicity pattern analysis are also important.

Volcano Seismology (IAVCEI, IAG): Most volcanic activities are accompanied by seismic activities, and thus seismic observation in volcanic regions is inevitable. Revealing the processes of interaction between earthquakes
and volcanic activities would be a clue to better understanding the triggering effects between eruptions andearthquakes. Furthermore, seismology can provide useful tools for the development of physical volcanology.
To obtain a detailed image of seismic structure of volcanoes, enhanced seismic observations in volcanic areas
as well as the advancement of theories and techniquesof seismic wave propagation and modeling in strongly
heterogeneous media will be essential.

Communication with Decision Makers: In case of catastrophic disasters, scientific information must be
smoothly transmitted to decision makers to take prompt
actions against hazards. Geoscientists should keep inmind that scientific information on natural disasters
should be provided in layman’s words to avoid miscommunication.
Information Technology: It will be useful to create a system using information technology as a communication
tool in case of emergency. Outer space monitoring withsatellites for earthquakes and disasters may be helpful
in immediate transmission of rescue information. It isalso important to utilize rapid and reliable earthquake
ground-motion information for controlling large structures and complex systems to minimize the impact oflarge earthquakes on modern society.

Generation and Propagation of Tsunami (IAPSO):
Earthquakes in oceanic regions sometimes generatehuge tidal waves, tsunamis, which bring catastrophic
damages in coastal areas. The scientific investigationof its generation and propagation is required to createa practical warning system to mitigate tsunami disasters.
Seismology for the Earth and the Sun (IAGA): The
studies of free oscillations of the Earth and the Sunshare some common theoretical ground (e.g., Dahlen& Tromp, 1998). Further developments of seismology
would complement helioseismology, and vice versa.

Building Code and Quakeproof Building: In seismically
active areas, the legislation of appropriate building
codes is essential. Engineering solutions to strengthenbuildings against strong ground motions at a reasonable19

Coupling Between Atmosphere, Ocean and Solid Earth(IAMAS, IAPSO, IAG): How do the solid Earth, atmosphere and ocean interact with each other? How do theatmosphere and ocean shake the solid Earth? The development of a systematic Earth model integrating a variety of Earth processes, such as global warming, growth
and retrogression of polar ice caps, plate tectonics, continental evolution, etc, which fully incorporate the physics
and chemistry of the processes into their structure, considering the significant differences in time-scale, will be
a common ultimate goal of geosciences.

Brodsky, E. E. and H. Kanamori, Elastohydrodynamic lubrication of faults, J. Geophys. Res., 106, 16357-16374,
2001
Dahlen, F. A., S. -H. Hung and G. Nolet, Fréchet kernels
for finite-frequency travel times - I. Theory, Geophys. J.
Int., 141, 157-174, 2000.
Dahlen, F. A. and J. Tromp, Theoretical Global Seismology,
Princeton University Press, Princeton, 1998.
Furumura, T., K. Koketsu,.and K.-L. Wen, PSM/FDM hybrid simulation of strong ground motion for the 1999
Chi-Chi, Taiwan earthquake, Pure Appl. Geophys., 159,
2133-2146, 2002.

Water Cycle in the Earth (IAHS, IAPSO, IAVCEI): Howis water brought down into the deep Earth? What is therole of the water in the Earth? Can water be a catalyst forearthquakes? The process of transportation of groundwater and its implications to the precursory anomaliesof earthquakes will need to be evaluated quantitatively.

Hacker B.R., S. M. Peacock, G. A. Abers and S. D. Holloway, Subduction factory - 2. Are intermediate-depth
earthquakes in subducting slabs linked to metamorphic
dehydration reactions? J. Geophys. Res., 108, ESE 11,
10.1029/2001JB001129, 2003.

2.7 Conclusions

Jackson, I. Laboratory measurement of seismic wave dispersion and attenuation: Recent Progress, in Earth’s DeepInterior: Mineral Physics and Tomography From theAtomic to the Global Scale, pp. 265-289, ed. Karato,
S., Forte, A. M., Liebermann, R. C., Masters, G. andStixrude, L., American Geophys. Union, 2000.

There are a number of areas of challenging research related
to IASPEI to extend our scientific knowledge in the future.
Enhanced information about the Earth’s interior is important
for a better understanding of the present status of the Earthas well as its historical evolution as a planet. Unveiling thenature of earthquakes and their generation, incorporating avariety of information of relevant disciplines, will be essential to meet the societal needs, i.e., earthquake prediction andmitigation of their effects. The rapid advancement of modern technology will make it possible to open new fields ofinterdisciplinary sciences. The first decade of the 21st century will be the exciting years for the younger generation toachieve a further understanding of the Earth’s interior as well
as a dynamic system of the whole Earth.

Kendall, J.-M., Seismic anisotropy in the Boundary Layersof the Mantle, in Earth’s Deep Interior: Mineral Physics
and Tomography From the Atomic to the Global Scale,pp. 133-159, ed. Karato, S., Forte, A. M., Liebermann,
R. C., Masters, G. and Stixrude, L., American Geophys.
Union, 2000.
Kobayashi N. and K. Nishida, Continuous excitation ofplanetary free oscillations by atmospheric disturbances,
Nature, 395, 357-360, 1998.

2.8 Acknowledgment

Komatitsch, D., J. Ritsema and J. Tromp, The spectralelement method, Beowulf computing and threedimensional seismology, Science, 298, 1737-1742,
2002.

Some of the ideas outlined in this chapter have arisen fromanswers to a survey conducted in 2002. The author would
like to thank all of those who kindly shared their opinions;in particular, B. Chouet, E. R. Engdahl, H. Kanamori and K.
Suyehiro for their comprehensive comments on important issues of the IASPEI. I would also like to thank E. R. Engdahl,
B. L. N. Kennett, P. Suhadolc, Z. Wu, F. Simons and T. Harafor their reviews which helped to improving the report.

Laske, G. and G. Masters, Limits on differential rotation of
the inner core from an analysis of the Earth’s free oscillations, Nature, 402, 66-69, 1999.
Lee, W. H. K., H. Kanamori, P. C. Jennings and C.
Kisslinger, International Handbook of Earthquake andEngineering Seismology, Part A, Amsterdam; Tokyo,
Academic Press, 2002.

Bibliography

Lee, W. H. K., H. Kanamori, P. C. Jennings and C.
Kisslinger, International Handbook of Earthquake andEngineering Seismology, Part B, Amsterdam; Tokyo,
Academic Press, Academic Press, 2003.

Ben-Zion, Y, Dynamic ruptures in recent models of earthquake faults J. Mech. Phys. Solids, 49, 2209-2244,
2001.
20

Levander, A., E. G. Humphreys, G. Ekstrom, A. S. Meltzer
and P. M. Shearer, Proposed project would give unprecedented look under north America, EOS Trans. AGU, 80,
250-251.
Nicholson, T., M. Sambridge and O. Gudmundsson,
Hypocenter location by pattern recognition, J. Geophys.
Res., 107, ESE 5, 10.1029/2000JB000035, 2002.
Obara, K., Nonvolcanic deep tremor associated with subduction in southwest Japan, Science, 296, 1679-1681,
2002.
Park, J. and V. Levin, Geophysics - Seismic anisotropy:
Tracing plate dynamics in the mantle, Science, 296, 485489, 2002.
Sambridge, M., Geophysical Inversion with a Neighbourhood Algorithm -II. appraising the ensemble, Geophys.
J. Int., 138, 727-746, 1999.
Simons, F. J., G. Nolet and D. Bohnenstiehl, Scrap the cable:
identification and discrimination of seismic phases byautonomous floats, Geophys. Res. Abstracts, 5, 08035,
European Geophysical Society, 2003.
Song X. and P.G. Richards, Seismological evidence for differential rotation of the Earth’s inner core, Nature, 382,
221-224, 1996.
Suda N, K. Nawa, Y. Fukao, Earth’s background free oscillations, Science, 279, 2089-2091, 1998.
Tromp, J., Inner-core anisotropy and rotation, Ann. Rev.
Earth Planet. Sci., 29, 47-69, 2001.
van der Hilst, R., B. Kennett, D. Christie and J. Grant,
Project Skippy explores the lithosphere and mantle beneath Australia, EOS Trans. AGU, 75, 177-182, 1994.
Yoshizawa K. and B.L.N. Kennett, Determination of the influence zone for surface wave paths, Geophys. J. Int.,
149, 440-453, 2002.
Zhao, D., H. Kanamori, H. Negishi, Tomography of thesource area of the 1995 Kobe earthquake: Evidence
for fluids at the hypocenter?, Science, 274, 1891-1894,
1996.

21

22

Chapter 3

International Association of Volcanology andChemistry of the Earth’s Interior
E. E. Brodsky

from dike intrusions or merely a seismic swarm is still a difficult matter that is often decided based on expert opinion andexperience rather than quantifiable scientific predictions. The
physical process behind certain precursors, like inflation, may
be well-known, but others, such as tremor, remain enigmatic.
Even the relatively well-understood precursors are associatedwith only isolated pieces of the magmatic system rather thana comprehensive view of the magma-volatile-wallrock evolution.

The International Association of Volcanology and Chemistry of the Earth’s Interior (IAVCEI) promotes both researchin volcanology and efforts to mitigate volcanic disasters. IAVCEI also promotes research in the closely related fields of igneous petrology and geochemistry. As the major scientificproblem of volcanology is also one of societal import, thework and progress of the field is closely related to the individual situations in local communities. The value of an international organization like IAVCEI is to help integrate knowledge across boundaries, both political and intellectual. By
introducing this broad perspective, IAVCEI helps volcanologists turn their discussions from fire-fighting to strategies forpushing forward a scientific frontier.

3.2 Short-Term Priorities
In order to reach the long-term goal of quantifiable predictions based on physical interpretations of precursors, we needto concentrate on unraveling specific volcanic processes. The
following section highlights a few major questions in volcanology that could plausibly be answered by focused efforts
in the next 10–20 years. The questions are organized by process rather than methodology or discipline because answering
most problems will require a combination of techniques.
Strategies for achievement follow each set of questions. A
limited number of example studies are cited to illustrate andclarify the strategies suggested. The citations here are by nomeans a complete survey of all work done in the field nor isthis discussion an exhaustive list of interesting problems in
volcanology. The purpose of this report is to focus on opportunities for rapid and important advancement of the basic
science.
Many of the important problems do not require state-ofthe-art technology or large-scale research investments. Several of the suggested research strategies are achievable bysingle investigators in regions without major technologicalinfrastructure. Scientists in developing countries will likely
continue to make fundamental contributions to the field.

3.1 Long-term goals
We would like to know accurately what are the processes
leading to an eruption, and how do these processes relate toobservable precursors such as volcanic tremor, earthquakes,
gas discharge events and deformation. Why do volcanoes
erupt; i.e., why does the magma not remain as an intrusion
at depth? We would like to be able to use this knowledge toaccurately forecast not only when an eruption will occur, butalso the size and type of the eruption. We should also be able
to distinguish an impending eruption from mere unrest.
This wish list may seem difficult to achieve, but we are
not as far from it as some might imagine. Eruptions at wellmonitored volcanoes seldom occur without warning. In broad
outlines, we know that volcanoes erupt because the overpressure of the volatiles exceeds the strength of the confining material. However, the quantitative details behind this scenario
are still elusive. The type of the eruption at a given volcano,including its potential explosiveness, is usually forecast basedon the previous history of the volcanic system with varying
degrees of accuracy. Distinguishing true impending eruptions
23

3.2.1

Initiation

The raw data of the climate and volcanological record will
come from a combination of geological studies, tree ringsand especially ice cores. Numerical climate modeling with
Global Climate Models (GCM) informed by an accurate understanding of the volcanological inputs and uncertainties canaddress these questions. Gas monitoring data including isotopic compositions are necessary inputs to volatile mass budget considerations [Hilton et al., 2002].

What begins an eruption? Is it the failure of the edifice or thepressurization of the chamber due to entirely internal properties? What is the role of external sources of volatiles such as
groundwater? Is the intrusion of new magma or an episodeof mixing necessary to start a new eruptive episode?
Progress could be made here by detailed studies of instrumental records of the first few minutes of an eruption, petrological studies including kinetic constraints on magma rise
rates [Rutherford and Hill, 1993; Geschwind and Rutherford,
1995], and comparison of precursory activity across many examples of historical eruptions [Newhall and Dzurisin, 1988;
Benoit and McNutt, 1996].

3.2.2

3.2.5

What determines the runout distance of pyroclastic flows? Oflava flows? Of lahars?
Geological deposits record the emplacement of flows andso can be interpreted to determine the processes ending movement [Branney and Kokelaar, 1992]. Laboratory analog experiments have had considerable success in quantifying themorphology of lava flows in terms of dimensionless parameters; similar approaches can be taken to runout length [Finkand Griffiths, 1998]. Laboratory studies of silicate melt rheology again help relate the analog materials to the real systems. Images of flow on other planets can extend our parameter ranges to test theories [Zimbelman, 1998].

Explosive/effusive transition

What combinations of volatile abundances and magma
chemistries lead to explosive rather than effusive eruptions?
Are there any observable indicators of the state prior to eruption for a volcano that has a history of both types of behavior?
Promising leads on the answer to the first question havecome from laboratory experiments on natural materials andanalog studies [Martel et al., 2001; Ichihara et al., 2002].
Experimental petrological studies of silicate rheology as afunction of composition, volatile content, crystallinity, temperature and pressure connect the analog studies to the natural systems. The observational question will likely be answered by well-integrated modeling and observational studies of very active volcanic systems like the ongoing Soufriere
Hills, Montserrat eruption that regularly produces both typesof activity [Druitt and Kokelaar, 2002].

3.2.3

3.2.6

Interactions with Tectonics

When do earthquakes trigger eruptions? When do eruptions
trigger earthquakes? How?
Triggering problems can be approached with statisticalstudies of the historic record [Linde and Sacks, 1998] as well
as examining monitoring records (thermal, gas, hydrothermal, deformation and seismic data) for evidence of coupling[Johnson et al., 2000].

Eruptive Plumes

3.2.7

What are the expected plume heights and dispersal patterns
for realistic eruptions?
Much theoretical progress has been made on plume heightsfrom idealized eruptions [Wilson et al., 1980; Sparks and Wilson, 1976; Valentine and Wohletz, 1989; Neri and Dobran,
1994; Woods, 1995], yet there still are comparatively few
studies comparing the predictions to field data. Field data
now encompasses satellite images as well as more conventional maps of deposits [Krotkov et al., 1999]. Comparisonswith the data will likely require incorporating realistic multiphase properties, large depressurizations, 3-D effects andcompressibility into a new generation of numerical models.

3.2.4

Flow Emplacement

Magma Storage

Are magma storage areas chambers or plexuses? Is the storage body created by a single emplacement event or repeatedinjections? What is the relationship, if any, between storage
body size and eruptive volume? Do magma bodies convect
and if so, for what parameter ranges? What is the volatile
content in the storage areas?
Geological studies of either erupted ignimbrites and emplaced plutons give the most direct data on magma chamber
heterogeneity [Hildreth and Fierstein, 2000]. Laboratory andtheoretical studies could connect microstructure and zonation
to specific parameters. Seismic and other geophysical methods provide direct constraints on the geometry of active bodies [Auger et al., 2001]. Ultimately, the petrological story
should be connected to the physical story.

Climatic effects of eruptions

Can we predict the global pattern and amplitude of temperature decrease from a given volcanic eruption? How regionally variable are these effects? What is the long-term role ofvolcanic volatiles in the atmospheric mass budget?

3.2.8

Conduit Transport

At what stage of an eruption is the conduit geometry deter24

mined? When is magma transport by percolation rather thanconduit flow? What role does thermal buoyancy play? Does
the collapse of conduits end eruptions? Where and how does
degassing take place in a conduit?
Coupled solid-fluid numerical models will likely be an important part of answering these questions. Magmatic rheology is once again a crucial input to the models. Geologicalstudies of wallrock entrainment and abundance will pose fundamental constraints for the models. Gas studies constrain
the degassing history.

and diabase together caused much confusion, it is almost inevitable that the currently used empirical seismicity classification is misleading in some respects.
Overcoming these barriers will require combining data andmodels by asking questions like: Where are the earthquakes
relative to the magma? Is their location controlled by thestress field or local structures at the hypocenters? What controls the frequency of volcanic seismicity?
High-resolution earthquake relocations provide powerful
insights into the question of location [Gillard et al., 1996].
Well-integrated studies of these locations and the theoreticalpredictions of coupled fluid-solid models can explain why
the earthquakes are located in the observed places [Rubinet al., 1998]. Connecting the frequency of volcanic tremor
and long-period events to physical processes may benefit
from comparing the volcanic timeseries with other observables such as gas, chemistry or deformation. Forward models
that predict multiple observables based on coupled fluid andsolid mechanics will likely be a necessary step in solving thisproblem and others like it.

3.3 Recommendations for Volcanology
In general, attacking these problems will require combining
multiple techniques and comparing multiple eruptions acrossdifferent volcanoes. The above discussion suggests two general categories for improvement: (1) synthesis of observations and modeling and (2) instrumentation.

3.3.1

3.3.2

Observations and Modeling

Instrumentation

As a natural science, volcanology is propelled forward by observational data. Quantitative instrumental data connects observations to processes and ultimately to predictive models.
The last decade has seen major improvements in instrumentation, including the widespread use of InSAR (Figure 3.1),
GPS monitoring and broadband seismometers. Increasingly,
active eruptions are being monitored and forecast by primarily instrumental means. The education of the next generationof volcanologists must take this fact into account. In addition,
further technological developments are needed to address thefollowing issues.

Although vast technological progress has been made in observing volcanoes and major conceptual and numerical leaps
have been made in modeling them, there is still a fundamental lack of connection between these two major sides of volcanology. The inputs to the models are generally not the observables in the field. Theorists would like to know magma
chamber volatile content and viscosity while field scientists
report number of earthquakes and gas discharge. Closing thisgap is going to require efforts from both sides. The modelers need to develop models that include degassing and deformation. A model that is not connected to data is useless.
The field scientists are going to have to invert their resultsfor properties in the magma. Numbers that are not connected
to a real process are meaningless. New initiatives like theWOVOdat project discussed below could broadly disseminate the raw observational data. This distribution will be an
important tool for making progress.
The study of volcanic seismicity is a special case of theinterface between observation and modeling. Many groups
consider volcanic seismic signals to be the most reliable precursors to an eruption, and therefore, their physical interpretation is a priority in the field. However, the interpretation ofthese precursors is still so preliminary that it was not possible
to work volcano seismicity into the process-oriented shortterm priorities of the previous section. Is tremor giving information about the initiation process, conduit transport orsome other physics? Volcano seismologists today are like theearly petrologists who first organized a taxonomy of observations and only later developed an understanding of their genesis. Just as the early rock classifications that placed limestone

The narrowing geodesy/seismology bandwidth gap
The classical instrumentation of volcanic geodesy and seismology has converged. Broadband seismometers can measure velocity and displacement from 50 Hz to hundreds of
seconds. Real-time kinematic GPS systems monitor displacement changes over seconds or months and years. Gravimetry has historically been used to measure changes over years,
but now modern digitizers allow data to be logged over seconds. These overlapping bandwidths have some distinct advantages. We can now completely cover the spectrum andcan reasonably compare data from diverse tools. However,there are also some subtle problems. Have certain techniques
become redundant? The interpretation of a classical technique outside its classical bandwidth can be problematic andplagued by response issues as instrumentation is pushed toits limits. It now seems within reach to design a single motion sensor over all relevant wavelengths. Such a leap could25

Figure 3.1: Example of InSAR deformation data on a shaded relief topographic map of the central Andes. Black squares show
the radar frames used in this remote-sensing study. Black triangles show the 1113 potential volcanic edifices. The red line in
the ocean is the location of the trench. Color shows InSAR interferograms indicating active deformation. Each color cycle
corresponds to 5 cm of deformation in the radar line-of-sight (LOS) direction. Inset maps provide detailed views of the centersof volcanic deformation: a., Hualca Hualca, Peru, time span 6/92–4/96 (3.9 yr), b., Uturuncu, Bolivia, time span 5/96–12/00(4.6 yr), c., Lazufre, time span 5/96–12/00 (4.6 yr), all of which are inflating, and d., Robledo, time span 5/96–10/00 (4.4 yr),
in NW Argentina which is deflating (From Pritchard and Simons [2002]).
of degassing and partitioning can provide a useful starting
point for predictive modeling of eruptive dynamics. SO 2 concentrations have been measured for decades, but it is only recently that other components of the plume have begun to bemeasured. Instrumentation, such as FTIR that measures multiple volatiles, should be developed and deployed routinely.

greatly reduce the cost of volcanic monitoring while increasing the ease of interpretation of datasets.
Remote sensing & robotics
Fieldwork on active volcanoes is inherently dangerous. Increasingly, technology is able to replace hand-sampling andin-person monitoring. Satellite remote sensing has madegreat strides in measuring deformation, thermal anomalies,
ash dispersion and gas discharge. Satellites provide excellent spatial coverage, but they do not resolve rapid timedependent processes or trace chemical compositions. Although we should certainly attempt to expand satellite dataand its availability, we will still need locally deployed instruments to measure such staples of the field as seismic waves
and fumarole chemistry. There have been some efforts to use
robotics to deploy such nearfield instruments, no system has
yet been completely successful. A renewed push on this front
is necessary in order to assure high-temporal resolution intracrater monitoring.

Real-time integrated datastreams
Modern telemetry makes it possible to collect large quantities
of data in real-time. Some techniques, like seismology, havealready been able to capitalize on this ability, while others,
like gas monitoring, are still developing the technology. Realtime simultaneous display of multiple observables has obvious advantages for hazard management. It would also benefit basic research by both facilitating the integration of datatypes and providing the framework for ready comparison ofmodels and data. In particular, if all the relevant observables
were acquired as digital datastreams, whole new methods oftimeseries analysis would become possible. Theoretical predictions could be tested in a forward sense. Formal data assimilation techniques could be used to update and validate
physical models. Even more speculative methods, like timeseries continuation, might someday become practical prediction tools and windows into physical processes.

Gas monitoring
Theoretical studies indicate volatile abundance is a major parameter in determining eruptive style. Observational constraints on in situ volatile concentrations coupled to a model26

3.4 Recommendations
and IUGG
3.4.1

for

IAVCEI

3.5 Opportunities forplinary Research

Volcanoes literally explode the boundaries between thespheres of geoscience. Opportunities for interaction exist between IAVCEI and each of the other associations. Possibilities include:

Travel for Observatory Scientists

IAVCEI should raise funds specifically designated to bringvolcanic observatory scientists from the developing world tomajor conferences such as AGU, EUG and IAVCEI. This central observatory travel fund should be a priority as it would
address several issues. The fund could help observatory scientists present their data themselves. The fund could also
facilitate modeling-observation interactions by helping observers appreciate state-of-the-art scientific questions and allow modelers direct access to observers’ experiences. It could
also help observatory scientists discuss logistical and procedural matters across international boundaries that could improve overall data quality and provide a uniformity of observations that is required if we are to have true cross-volcano
comparative studies.

3.4.2• IAMAS: Exploration of the effects of volcanism on climate (Section 3.2.4).
• IASPEI Earthquake-volcano interactions (Section
3.2.6).
Development of robust wave propagation
modeling tools suitable for the highly heterogeneouspaths of volcanoes. Characterization of explosive andother non-double couple seismic sources. Delineationof geometry of magma bodies (Section 3.2.7).
• IAG: Geodetic instrumentation at high time-resolution(Section 3.3.2).
• IAGA: Numerical and theoretical tools for modelinglarge-scale compressible jets (Section 3.2.3).

WOVOdat

Interdisciplinary research could be facilitated by disseminating a variety of data in a uniform format to be accessible to anyone without any special connections. WOVOdat(http://www.wovo.org/wovodat.htm) is a project to do justthis and deserves IUGG’s full and active support. The project
would also be facilitated if the observatory scientists were
better connected to the research process as suggested in theabove discussion of a the central observatory travel fund.

3.4.3

Interdisci-• IAPSO: Mid-ocean ridge volcanism and earthquake interactions (Section 3.2.6). The role of submarine volcanism in the biological and physical environment of ridges.
• IAHS: Groundwater as a trigger for explosive eruptions (Section 3.2.1). Using water well data to measurestrain, temperature and chemical changes in the coupledhydrothermal-volcanic system.

Communicating with Society

3.6 Conclusions

Scientific progress will not mitigate hazards unless results arecommunicated effectively to local decision makers during acrisis. Over the past 20 years, much attention has been paid
to the interface between scientists and politicians with significant practical and scholarly research on hazard management.
Still, sometimes turf wars and scientists inexperienced in crisis management lead to difficult and dangerous situations. As
a new generation of scientists emerges, we all need to be constantly reminded of the seriousness of our task and retrainedon appropriate ways to interface with local communities. Crisis teams must effectively combine the local knowledge ofresident scientists and observers with the constantly evolving
skills of foreign specialists. Technical results must be madeaccessible without sacrificing factual accuracy and completeness. In order to facilitate this process, IAVCEI should continue to serve as a central source of guidelines and training oncrisis management.

Recent instrumental advances and the broad disseminationof observatory data are bringing volcanology into a new era.
IAVCEI and the volcanology community can take advantageof the situation by targeting our resources to answer the questions most likely to generate a quantitative, portable model ofwhy volcanoes erupt.

3.7 Acknowledgments
The author is grateful for responses to a survey in September 2002, especially C. Newhall, who contributed a complete
report on the intersection of modeling and observations. Several reviewers including K. Cashman, T. Fischer, M. Manga,
M. Mangan, S. Prejean, M. Pritchard and R.S.J. Sparks contributed to improving the report.
27

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Branney, M.J., and B.P. Kokelaar, A reappraisal of ignimbrite emplacement: changes from particulate to nonparticulate flow during progressive aggradation of highgrade ignimbrite, Bull. Volcanol., 54, 504–520, 1992.

Pritchard, M.E., and M. Simons, A satellite geodetic surveyof large-scale deformation of volcanic centres in the central
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Chapter 4International Association of the PhysicalSciences of the Oceans
C. Simionato

4.1 Introduction

in observational tools, especially in remote sensing, together
with the development of new and powerful computer based
tools are producing an increasingly global and complete picture of the three-dimensional ocean circulation and great advances in our physical understanding of the oceans. The field
is beginning to assemble the elements to reach the ultimate
scientific goal of attaining a comprehensive understanding of
the physics of the ocean.

The aim of physical oceanography is to understand, modeland predict ocean processes by combining observations withmathematics and fluid mechanics. Physical oceanography isconcerned with how water moves and mixes in the ocean andhow water transports and distributes heat and dissolved and/orin suspension chemicals, nutrients, plankton, sediment, andpollutants. This discipline does not only include the study ofthe large oceans and shelf seas but also of estuaries, lakes andlarge bodies of water on other planets and moons.
Physical oceanography is an extremely challenging science. One of its central difficulties, in common with othergeosciences, is the lack of a laboratory to experiment in.
Physical oceanographers must rely, therefore, on direct observations and interpretations of these data with fluid mechanics, applied mathematics, powerful computers and modern descriptive tools. Another great challenge is the range ofspace and time scales that must be measured and modeled byany successful effort to understand the fluid behavior. Every scale, from the seconds to hours of the waves and tides
that modify the shoreline to the centuries and even millennia
of the ocean thermohaline circulation response scale, going
through a number of intermediate scales, must be considered.
Comprehensive observation of these processes demands adifficult and expensive combination of in situ and remotemeasurements for very long periods of time and large distances, which just started in relatively recent years. Other
not minor tasks include the need for an international cooperation effort to observe and understand the system, giventhat the ocean knows no national boundaries but behaves as awhole, and the need for an interdisciplinary approach in orderto give answers to many important environmentally relevant
questions.
These needs make progress in physical oceanography to be
intrinsically tied to progress in technology. Recent advances

The International Association of the Physical Sciences of
the Oceans (IAPSO) is one of the seven associations thatcomprise the International Union of Geodesy and Geophysics(IUGG), founded in 1919. IAPSO has as its prime goal ”promoting the study of scientific problems relating to the oceans
and the interactions taking places at the sea floor, coastal, andatmospheric boundaries insofar as such research is conductedby the use of mathematics, physics, and chemistry.” One of
the main objectives of IAPSO is to organize, sponsor, andco-sponsor formal and informal international forums, permitting ready means of communication amongst ocean scientists
throughout the world. In this sense, the IUGG general assembly in Sapporo, Japan, provides an excellent context forreflection and interdisciplinary discussions about our visionof how geosciences should develop during the next decades.
This report intends to provide a view of the main directions inwhich physical oceanography research could progress duringthat period and to serve as a starting point for those discussions.

The results of previous workshops and surveys, together
with a survey and revision process among several scientists
around the world were very valuable in the preparation of thisreport.
29

4.2 A view of the future of research in
Physical Oceanography

spatial scale, and its response to natural and anthropogenic forcing to predict, manage, and modify its behavior to help sustaining the human race and our environment.
Even though our knowledge of the oceans and their rolein the climate has substantially improved during the last
decades, we are still far from fully reaching this goal that
requires the construction of a valid ’Earth Model,’ encompassing other geosciences in addition to physical oceanography. Besides the inherent limits of predictability (further discussed in the IAMAS Chapter 6), the extreme complexity ofthe system imposes technological and knowledge limits to afast development of the desired predictability. The construction of such a model will require a much better understandingof all of the processes taking place in the coupled ocean-landatmosphere-cryosphere system and their interaction with biogeochemical processes together with a much larger computing capability. Regarding ocean’s role in such a model,
ocean’s physical, chemical and biological processes are intimately interconnected through a number of networks, interaction and interdependencies and feedback processes thatmust be fully understood prior to any attempt to modelingthem and obtaining truly meaningful predictions. Meeting
this scientific challenge requires research ships, incorporating new platforms of observation and sampling, acquiringlong-term records of the relevant variables, developing new
instruments, building a real time global observation system,
improving theoretical knowledge, models and the ability toassimilate data and update forecast models, and increasing
computer power.
Besides addressing the above goals, given the immediatesocietal demand related to environmental problems, physicaloceanography should also identify intermediate goals. Twosuitable aims for shorter time scales that meet great challenges to ocean sciences in general, taking advantage of thedeveloping technology, providing important services to thesociety and constituting an intermediate step to the proposed
long-term goal, could be:

Even though basic research, independent of any practical concerns, is critical to the advancement of science and the development of technology, the relevance of science is often measured in terms of its value to the end user. If the world issurvival-oriented, then this last aspect will become increasingly more significant during next decades for geosciences ingeneral, and physical oceanography in particular. Nowadays,
the main societal concerns relating to physical oceanography
are the humankind impact on the ocean and climate and thesustainability of the environment. Humanity is faced withpressing marine research problems, many of which arise fromthe need to accommodate multiple uses of the ocean and fromthe ever-increasing concentration of the population near thecoasts. The demand for ’ocean products’ from the society
increases as it understands more about the anthropogenic impacts on the oceanic systems and the need for a better understanding of the ocean’s role in controlling global chemical,hydrological, and climate processes. It can be expected thatapplied physical oceanography in support of socioeconomicplanning and regulatory activities will become more significant as we move closer to the limits of sustainable use of theenvironment, and it should be emphasized that ’good science’
and ’societally relevant science’ are not necessarily mutually
exclusive.
Physical oceanography has made giant steps in both directions. In the past decade, major breakthroughs were made in
our understanding of ocean biology, chemistry, geology andphysics. Such potential has been made possible by increasing capabilities in the areas of computation and rapid oceanobserving technologies. These new capabilities are providing
unprecedented views of the ocean basins, their changing interaction with the atmosphere, the great biological shifts innear-surface waters, and the long-hidden deep ocean basins.
Advances in ocean numerical modeling made possible by increased knowledge are going and will go on, greatly enhancing our understanding and predicting capability on time andspace scales important to society. The promise of progress inthe future is predicated on these new tools and the new ”look”
at the ocean that these tools have made possible.

4.3 Long-term goals
Oceanographyfor• To develop a comprehensive predictive capability for the
climate variations in a lifetime. The predictive capability should extend beyond foreseeing weather conditions
and ocean temperatures to include effects of natural andanthropogenic climate change on sea life, including infisheries and on land, which could, in turn, affect climate. The result of this work will eventually be a system capable of predicting climate fluctuations and theireffects on the biosphere, both on land and at sea spanning in a lifetime.

Physical

Considering the concepts of the previous section, ocean scientists’ ambitions and societal demands could merge in thefollowing long-term goal for physical oceanography:
To attain a comprehensive understanding of the functioning of the ocean and its interactions with the atmosphere, land, cryosphere and biota in every temporal and• To develop a comprehensive understanding of coastal
processes and their effects. As a result of this, we would
expect to be able to deal with coastal problems without
exclusive dependence on years of site-specific, routine
measurements.
30

Our present knowledge and capability, the continued development in technology and progress in physical oceanographic
research, promise that important advances can be done in thisdirection during the next decade.

nificant enough to complicate and/or mask climatic variability produced by anthropogenic action. To assess the degree
to which these forcing mechanisms are controlling our modern climate and the degree to which man has affected theclimate system, the variability of the natural global climate
must be understood. Given that we cannot wait to gather
enough data to directly observe the climate variability, it
is necessary to expand our data base and frame hypotheses
about past climate change and ocean circulation using paleooceanographic studies and proxies, like ice cores, varved sediments, tree rings and corals (See Figure 4.1). Models are
the essential tools for casting the results of theory and observations and for providing new hypothesis about the involved
processes.
During the last decades, as a result of improved and extended observations, the development of pilot experiments
and the evolution of numerical modeling and data assimilation techniques, there have been important advances in our
understanding of the present and past climate systems.
One of the most important achievements has been the large
improvement in observation due to a combination of new
observational and measurement techniques and the development of global experiments. In-situ measurements of highaccuracy made through experiments as WOCE (World Ocean
Circulation Experiment http://www.woce2002.tamu.edu);
CLIVAR(Climate
Variability
andPredictability
http://www.clivar.org) and JGOFS (Join Global Ocean
Flux Study http://www.uib.no/jgofs/jgofs.html) have given
an unprecedented view of the contemporary ocean circulation, have created the first long time series of CO2 in theoceans and have allowed an improvement in the estimationsof oceanic heat and CO2 transports. Polar orbiting satellites are providing a global coverage of critical properties
every few days, like sea surface height (Topex-Poseidon
http://topex-www.jpl.nasa.gov) and ocean color (SeaWIFS
http://seawifs.gsfc.nasa.gov), that allow the study of thefluctuations is near-real time and at global scale.
The new measurement techniques have made possible direct observations of diapycnal mixing and basin-scale absolute velocity and wind fields and improved measurement
and parameterization of air-sea fluxes, allowing for a better
theoretical understanding of the ocean’s role in climate andits modeling. The increasing sophistication of drifters andfloats has allowed a view of the ocean circulation through Lagrangian pathways. The exploration under ice by sensors carried on autonomous vehicles permits us to survey the deep
convection in progress, improving our knowledge and understanding of the water masses formation. Important advances have also been made in paleo-oceanography by improvements in the dating techniques and the development of
new proxies. TOGA (Tropical Oceans and Global Atmosphere http://ioc.unesco.org) program has established the basic dynamics of ENSO and has lead to seasonal predictions
with useful skill. Innovations in modeling and data assimi-

4.4 Short term focus for Physical
Oceanography
Reaching the aims proposed in the previous section requires
development in almost every aspect and sub-discipline ofphysical oceanography, together with progress in meteorology, geochemistry and other geosciences besides a closer interaction among them. To be in position to reach those aims
on shorter time scales, oceanography must improve our understanding of the ocean processes at every spatial and temporal scale. Some of the critical issues that should be addressed
during the next decade regarding the two aims proposed in theprevious section are outlined below. It must be emphasizedthat even though the global climate and coastal problems areanalyzed separately, they are intimately interconnected, as
they constitute two pieces of a unique ’ocean puzzle.’ Therefore, progress in one of the areas depends on, and reciprocallywill have important repercussion in, the other one. Moreover,many of the needs are common.

4.4.1

Climate and climate change prediction

Understanding how global climate evolves on decadal to centennial time scales is one of the most pressing environmental
challenges that geosciences face today. Physical oceanography plays a huge role in unraveling the evolution of climate
because of ocean’s enormous importance in establishing theclimate. Oceans contain 50 times more carbon than the atmosphere, dominate the hydrological cycle and, given water’s large heat capacity, stores extremely large amounts ofheat. These features give the ocean the capability of acting as
a buffer, moderating both natural and anthropogenic forcedchanges in the climate system. Ocean circulation, throughlarge-scale currents, thermohaline circulation, mesoscale motions and diffusive processes, plays an important role in distributing the heat, carbon and freshwater that is exchanged
with the atmosphere, determining the climate to a large extent. The oceans absorb 40% of the carbon dioxide that isemitted into the atmosphere and are responsible for 50% of
the polewards heat transport. As a result, the ocean sequesters
heat and carbon in the deep waters and sediments.
Global climate prediction is probably the most difficult
problem that our field has encountered. The dynamics arecomplex and involve a number of processes and scales. Theirlong time scales combined with the relatively short period ofwell-instrumented records of observational data make the direct observation of climate variability difficult or even impossible. Internal oscillations create climate variability sig31

Figure 4.1: The ocean global thermohaline circulation (shown schematically in the upper left panel) maintains the present
mild climatic conditions on the Northern Hemisphere. Upper right panel displays the change in surface air temperature after
a collapse in the thermohaline circulation according to the Hadley Centre HadCM3 Model, showing an important coolingin that Hemisphere. Understanding this and other climate variability and climate change issues will require the applicationof realistic coupled models integrating all of the processes involved, the improvement of the observational base and a better
understanding of ocean processes. Proxy data, as those shown in the pictures of the figure, are necessary to expand our data baseand frame hypotheses about past climate change and ocean circulation Figs. courtesy of Clivar Project (http://www.clivar.org)
and Vellinga, Michael and Richard Wood, 2002, Climatic Change, 54, 3 (251-267).
lation are including the full range of ocean biogeochemical
cycles in models, leading to better predictions.

tions, a better understanding of the processes and couplings
between the different parts of the climate system is needed.
The field requires, therefore, further research and investment
to develop, apply and evaluate more realistic coupled models
that integrate all of the processes involved, the improvementof the observational base and a better understanding of ocean
processes. Some of the main problems in this field, clearlyinterconnected, and several ways in which progress might bemade are given in what follows.

Innovative pilot experiments, like the Iron Fertilization(SOFeX http://www.mbari.org/expeditions/SOFeX2002) andthe Brazil Basin Tracer Release Experiments (BBTRE
http://www.whoi.edu/science/AOPE/cofdl/bbasin), pave theway for rapid advances to the understanding of CO2 sequestration in the deep ocean that could reduce or eliminate theatmospheric residence time of this gas, mitigating the climatechange.

Thermohaline circulation

Nevertheless, in order to reach the aim of developing acomprehensive predictive capability for the climate varia-

The thermohaline circulation (See Figure 4.1) is one of themost important aspects of the ocean role in climate at long32

time scales. A quantitative understanding of these pathways
and rates of the warm-to-cold conversion of water is crucial
for both climate and climate change prediction. In order tounderstand the nature and extent of the ocean-induced delay
in atmospheric warming created by rising CO2 levels, determining the ocean’s deep and intermediate water pathways for
distributing heat and CO2 and how these pathways influence
the lag between atmospheric input and response is fundamental. An improvement of the understanding of the processes
that control convection, affecting the thermohaline circulation’s rate, volume and properties, is needed, particularly therole of fresh water. To reach this goal, a better understandingof the hydrologic cycle in climate is required. Knowledge offreshwater inputs from continents, precipitation, melting seaice, and an improved knowledge of the rates, pathways, storage and redistribution of water in all its phases are necessary.
Understanding and quantifying the thermohaline circulation
requires the study of a number of oceanic processes as meridional overturning, subduction, convection, western boundary
currents and diapycnal mixing. The study of these processes
is important as well as they control the geochemical recyclingof nutrients.
Global freshwater circulation and sea-ice
As discussed above, the hydrological cycle is crucial forthe thermohaline circulation, and it also has a direct impact
on human activity and ecosystems. Unfortunately, data are
too sparse to describe and properly understand the fresh water cycle, and models are still too crude to represent its different temporal and spatial scales of variability. A significant
effort is required to observe and model the different aspectsof the hydrological cycle and, in particular, of the fresh water fluxes between the different components of the climate
system (land-ocean, land-atmosphere, ocean-atmosphere-seaice). As an example, a key aspect that needs further development is the representation of sea-ice in numerical models.
Because of its insulating capacity, its radiative properties andits creation of saline brine during freezing, sea-ice exerts profound effects on air-sea exchange. Its effect is obviously amajor factor in high-latitude climate and has profound influence on the thermohaline circulation. The soon to become
available satellite borne surface salinity measurements are expected to provide valuable information on the hydrologicalcycle.
Ocean mediated climate fluctuations
Our capability of predicting the dynamic evolution of
the climate system depends upon our understanding of thedecade-to-century climate variability of the coupled oceanatmosphere system. Therefore, efforts must be made to understand ocean and ocean-atmosphere coupled modes of oscillation at those scales. Even though further studies arestill required, the development of ENSO theories, observation, models and forecasting systems provide an example ofa success story when international capabilities are joined inobserving, understanding, modeling and predicting climate.

Other oceanic and climate phenomena would deserve similar international joined efforts. Examples are the Antarctic Circumpolar Wave, with a period of around 10 years
and the North Atlantic Oscillation, with decadal periods.
The strength and pattern structure and the coupled oceanatmosphere dynamics of these climatic modes must be further understood. The role of greenhouse gases in forcing andmodifying these modes should also be further explored.
The surface mixed layer
The surface mixed layer of the ocean is the one that directlyinteracts with the atmosphere, introducing into the ocean thewind and buoyancy fluxes. Misrepresentation of this layer
can produce serious failures in predicting the onset, duration and depth of convective overturning events that set theproperties of the subsurface water masses, and thus affect thethermohaline structure and the meridional circulation. Turbulence and flow structures of the scale of the mixed layer
depth greatly complicate the physical behavior of flows (seeFigure 4.2). Processes occurring at short time scales have,as well, an impact in this layer, as the diurnal cycle in heat
flux that has a profound effect on the ocean surface, surface
heating, and convection. Finding an optimal level of closurefor mixed-layer problems represents a challenge to modeling. New instruments, like microstructure profilers, could optimally support the modeling activities.
Effects of complex seafloor topography and down-slope
flows
Ocean circulation is very sensitive to bathymetry details.
Seafloor mountains, ridges and continental rises exert horizontal pressure forces that are crucial elements of the circulation. Topography channels and breaks the flow into eddies
that cannot be represented by moderate resolution models. As
part of the meridional overturning circulation, water sinks innarrow streams or ’plumes’ at high latitudes. As they descend, waters from intermediate depth layers are entrained
into them, their transport increases and recirculating flows in
the surrounding ocean are driven. Accurate representationof these concentrated flows in models is an important goal,
which can be achieved as computer power increases.
Ocean turbulence
Ocean turbulence plays a critical role in the transfer ofmass, momentum, salt, heat and other water properties fromthe larger scales of generation or input to the smallest scalesof dissipation by molecular processes. Turbulence also has
an impact on processes as diverse as zooplancton detection of
prey and avoidance of predators, transfer of CO2 across the
air-sea interface, and mixing of heat and nutrients throughout
the ocean. A better understanding of ocean turbulence andits role in ocean mixing, and how ocean mixing can be accurately parameterized is essential for developing new ocean
circulation models for studies ranging from local ecosystem
dynamics to coupled atmosphere-ocean dynamics.
Abrupt climate change
Paleo-oceanographic records show clear evidence that33

Figure 4.2: Sea surface elevation variability modeled by a high-resolution (1/12◦ grid), layered model of the Atlantic circulation
with ECMWF daily forcing for the years 1979-1984 (left panel) compared to TOPEX / ERS-1 data (right panel). The highvariability that characterizes oceanic circulation, increasingly better reproduced by models, is a central challenge to ocean
modeling. Fig. courtesy of R. Bleck, MICOM Project (http://panoramix.rsmas.miami.edu/micom) and P.Y. LeTraon (Space
Oceanography Division, CLS, Toulouse, France).
CO2 sequestration
Techniques for carbon sequestration are a possible option
to stabilize the greenhouse gasses concentration besides conservation effort and development of alternate energy sources.
Given that the oceans are the largest active reservoir of carbon, they could be the appropriate repository for the excessthat humans produce. Pilot experiments that either enhance
the biological carbon pump or directly inject anthropogenic
CO2 into the deep ocean have already been successfully carried out. These options of carbon sequestration should befurther explored together with the development of other techniques for mitigation.
Summary
Our predictive capability of the climate variations is currently handicapped by insufficient knowledge of the processes involved and the interactions between the different
components of the climate system, by difficulties in representing some of those processes in numerical models andby insufficient observations in the required time and spacescales. Nevertheless, with the observational database rapidly
growing and with sufficient computational resources to support experimentation with a variety of models, we are on track
to make rapid progress. One of the most important needs isabrupt (within a few decades) climate change took place inthe past, persisting for centuries. Even though the causes forthese changes are still uncertain, the thermohaline overturning and the tropical circulation have been both suggested as
possible mechanisms. Sophisticated climate models predictthat changes in the hydrological regime, resulting from global
warming, could reduce the rate of deep-water formation athigh latitudes, producing a rapid collapse of the thermohaline circulation. This collapse would have impressive consequences for the global climate, like an important reduction of
the mean temperature over Europe (see Figure 4.1). There arealso indications that rapid releases of greenhouse gases to theatmosphere may have induced abrupt climate changes in thegeological past. Therefore, it is important to determine thelikelihood that such an event could result from anthropogenic
activities. For that, it is necessary to understand what types ofocean conditions caused abrupt climate changes in the past,
and what the consequences were to the ocean’s ecosystems
and the atmosphere. Given that two mechanisms for rapidchange are known, and both of them involve the ocean partof the climate system, it is necessary to study whether othermechanisms have produced rapid changes in the past andwhether those events could be repeated in the future.
34

4.4.2the enhancement of our database. The importance and influence of satellite observations on research progress is evident, and therefore, it must be enhanced and further developed. Nevertheless, given that the ocean is virtually opaque
to electromagnetic radiation, remote sensing from space is restricted to the ocean surface and its upper parts. Thus, the fullunderstanding of the system requires sustained in situ observation. The very few existing long time-series stations capture the time domain at only one single point. New strategies
for observing the appropriate spatial correlation are required.
Deployment of a large number of new stations and efficient
tools, such as instrumented floats and vehicles will greatly enhance our ability to observe and predict important planetarychanges. Given that paleo-oceanographic studies are a key forunderstanding the evolution of climate, the efforts to extend
the detailed records of oscillations in the ocean and climate
system into the future should go hand-in-hand with efforts toextend them into the past. An increased knowledge of theoceanic fluxes of heat, water and biogeochemical properties
that drive climate, together with a better understanding of theinterplay of the internal oscillations of the deep and shallow
ocean, are essential for evaluating climate change and for mitigation planning.

Coastal oceans prediction

Even though the ocean margins occupy a relatively small portion of the ocean surface, its environmental importance isenormous. The coastal ocean (estuaries, continental shelves,
and the Great Lakes) represents the part of the ocean thatpeople most directly use, benefit from, and also affect. The
coastal ocean is important for a number of economic reasons,
including recreation, coastal development, mineral extraction, and fisheries. Indeed, most of the problems of sustainable ecosystems have a significant coastal component. This
environment is being strongly modified and impacted by human activities, and an urgent need for better understanding
the processes that influence and control it is emerging in order to provide cost-effective, accurate management advice.
In a broad sense, the great issue in the coastal oceans is how
materials are transported and exchanged between the land, estuaries, the continental shelf, and the deep ocean, all the while
undergoing physical, biological, and chemical transformations. This makes coastal oceanography extremely complex.
The complexity of the coastal systems, their small scale andhigh spatial and temporal variability have been the main limits for understanding the processes that influence and control
this environment. Nevertheless, the advent of new increasingly sophisticated sensing capabilities, the development of
new modeling and data assimilation techniques and the continuous increase in computing power are creating the conditions to make an important advance in our understanding of
the coastal systems, their prediction and management. The
field requires further research and investment to improve theobservational base, to understand the processes involved andtheir relations, interactions and feedbacks, and to develop, apply and evaluate more realistic models integrating all of theprocesses involved. A brief assessment of the main problems in this field and several ways in which progress might
be made are given in what follows.
Physics of coastal environments
Physical processes strongly influence the character of thecoastal ocean environment in a number of scales. Even
though recent work gives a first-order understanding of manyof the basic physical processes that act in coastal oceans, further research to gain a better knowledge of those processes
will be necessary in order to overcome the barrier of predictability. Some of those processes are:
The role of turbulent mixing in estuarine physics:
Vertical mixing controls the estuarine circulation and thesalt budget in most estuaries and plays a fundamental rolein most coastal physical and biological processes. A morecomprehensive and quantitative understanding of this process
would improve our modeling and predictive capabilities. Direct measurements are needed in order to reach this aim. The
new development of microstructure profilers is very promising in this context.
The behavior and dynamics of water plumes:

Large-scale numerical models of the ocean are the essential tools for casting the results of theory and observations into
rigorous form. Ocean modeling, data assimilation and theory,
therefore, must be continued, improved and employed. Fertile interaction of experiment, theory, data and modeling is, aswell, necessary, in order to make significant progress in our
understanding of the climate system.
Development within complex numerical models is particularly needed in areas of turbulent mixing and convection,complex sea-floor topography and down-slope flows, global
freshwater circulation and ice and upper ocean dynamics.
Models of biological and chemical processes are needed forprediction and understanding as, coupled with physical models, they allow exploration of ranges of response that can berealized, the conditions under which particular responses are
possible, and thresholds where undesirable responses mightoccur. Finally, it is necessary to continue developing ’wholesystem’ (Earth) climate models capable of predicting longterm climate change.
Deliberate tracer releases must be intensified in order toimprove our understanding of the turbulent processes in theocean that is crucial for a proper modeling of the climate
system. The execution of perturbation experiments has resulted in important new information on the rate of ocean mixing, on fundamental controls on biogeochemical cycles andon the possibility of carbon sequestration. These techniquesshould be adopted, and new classes of perturbation experiments should be done, as they have the potential to give us the
key to understanding climate and climate change processes.
35

River plumes are one of the primary sources of freshwater, nutrients, pollutants and sediments of the coastal ocean.
The study of the factors that influence the plume’s movement
and evolution over space and time and its interaction with theshelf and offshore or deep ocean currents systems is therefore
extremely important. Understanding of these processes canbe only reached through further observations and applicationof numerical models.
The dynamics of the surf zone and inner shelf:
Understanding the dynamics of the inner shelf is not only
locally important because of, for instance, its influence in the
coastal morphology, but also because of its important implication and the along and cross-shelf transports. Further fieldstudies are required to understand those processes and validate numerical model results.
The dynamics of wind-driven currents:
The knowledge of the shelf flow regime and the off-shelftransports is central for coastal applications. These processes
are strongly influenced by details of the bathymetry and wind
forcing on very small scales. Further development of highresolution numerical models and high-resolution observationof the forcing and topography are needed to address this problem.
The bottom boundary layer:
Due to the shallowness of the estuaries and shelf, turbulent
drag and mixing generated by near-bottom flow play a central
role in controlling many processes. Biota also has an effecton the bottom drag given that benthic biology modifies thebottom roughness. A better understanding of these processes
and their parameterizations is needed to improve numericalmodel’s predictions. Laboratory based studies and increases
in observational capabilities would improve this subject.
The shelf break fronts:
Even though the shelf break fronts are features present inmany coastal oceans, not much is known yet about them.
The detailed thermohaline and velocity structures of the shelf
break fronts and shelf break jets need to be quantified, andthe impact of these processes on material transport, the spreadof marine organisms and the formation of geobiological domains needs to be understood.
Physical forcing and biological processes
While some effects of physical forcing have been established, there is a great uncertainty in the mechanisms bywhich they influence variability in biological phenomena,even though it is known that this effect can be dramatic. Biology can have, in turn, an effect on physics, for example, due
to the aforementioned modification of the bottom roughness.
Assessing the effects of physical processes and their naturaland anthropogenic variability on coastal biological communities is a problem of clear ecological and economical importance that demands further efforts.
Land-Ocean fluxes
Material inputs to the coastal zone from land include organic and inorganic sediment, dissolved elements, dust andanthropogenic pollutants and nutrients. These inputs are influenced by the local watershed, meteorological characteristics and biogenic habitat quantity and quality. These material
inputs have a major influence on the chemistry of the global
ocean and are greatly influencing ecosystem processes, including food web dynamics, biological production and community structure. Some important issues that require further
study include:
Inputs of biologically important materials:
Even though the water flow and major element composition of larger rivers are reasonably well known, the chemical form of minor elements and organic matter that are transported from terrestrial watersheds to coastal environments isless understood. Riverine oceanic matter is fundamental in
the global carbon balance, and the minor elements are often
critical to coastal and oceanic ecosystems. The groundwater discharge can locally influence, in a significant way, thefreshwater contributions and often, has higher concentrationsof dissolved species. Efforts must be made to identify regionsof groundwater influence, its role in material flux and consequent ecosystem response.
Sediment fluxes:
Globally, rivers deliver around 20 billion tons of suspended
solids to the sea every year. These sediments are not chemically inert and may serve as a source or sink for nutrients, pollutants and other materials in the coastal ocean. While some
aspects of sediment resuspension and transport are understood and supported by field measurements, the conceptualand numerical modeling and prediction of sediment transport
requires further development. Bioturbation is a key process,as benthic organisms distribute the deposited material over acertain depth of the sea bottom, which in turn influences theerosion processes. There is a need, therefore, to investigate
the coupled system suspended particulate matter dynamicsbiology-morphodynamics. This is a fundamental need in order to construct confident budgets and to predict the evolutionof the shoreface and bottom topography under different conditions.
Carbon fluxes:
Margin sediments can be efficient in sequestering carbon,
and this preservation could influence the CO2/O2 balance of
the atmosphere on geological time scales. Nevertheless, themechanisms that control this sequestration are not well understood. Organic carbon buried in sediments may serve as a
substrate for microbial activity within the sediments, giving
rise to gas hydrates in ocean margins. Given the enormous
size of the reservoirs, these hydrates may have significant influence on the carbon cycle and the climate. Their distribution, nevertheless, as well as their generation rates, migration pathways through the sediments and rate of return to theocean environment are poorly known.
Anthropogenic influences:
Deforestation, agriculture, flow modification, coastal constructions, urbanization and other human activities dramati36

cally influence rivers, watersheds and coastal sediment transports by changing the amount of water that is transported andits chemistry. For instance, global river discharge of nitrogenand phosphorus and total organic carbon have doubled during
the past two centuries. Together with fishery exploitation, it
has produced the largest impact on biological processes incoastal ecosystems. Human activity injects into the atmosphere particles, aerosols and chemicals. The amount of thedust flux, its variability and its influence on biological systems through delivery of contaminants and limiting micronutrients is not clear. Similarly, biological communities are affected by other chemicals of anthropogenic origin released tothe ocean, like trace elements and toxics. Greater researchis needed to determine the ecological effects of human andnatural alterations in the quantity, quality and spatially explicit processes associated with coastal habitats. Efforts arealso needed to identify and predict how global warming andsea level rise will affect the distribution, abundance and landscape connectivity of various habitat types and their influence on associated processes and species. Interdisciplinary
research between physical oceanography, biology and chemistry, involving modeling and observations integration will benecessary to address these questions.
Exchanges between the Deep Ocean and Shelf Ecosystems
The connections and exchanges between the small-scale
processes of the shelf and the large-scale of the ocean are
increasingly becoming an important oceanographic issue, as
they can have a global impact. Localized export of material, for instance, can have global importance as it is transported far by ocean currents, changing the chemical properties of distant environments. Other examples are the growthof plankton populations, which affect carbon dioxide levels,and thus may be important in global warming scenarios, theanthropogenic pollutants that have reached the open ocean,which are known to be transported far from their sources
and the nitrogen global cycle, which is strongly dependent
on denitrification that takes place on the ocean margins. A
better understanding is needed of small-scale processes andsmall-scale aqueous systems (estuaries, wetlands, coral reefs)
to understand these exchanges and evaluate their impacts on
global issues. Quantifying the exchanges will be required todetermine the magnitude and time-dependent nature of shelfocean and sediment-water fluxes in interdisciplinary efforts
with geologists, biologists, hydrologists and biogeochemists.
Summary
The ocean margin occupies only about 10% of the global
ocean area, and a much smaller percentage of its volume,
but it dominates the economic importance of the sea. Material fluxes to the coastal zone are largely unidirectional,
from the land to the sea, and these fluxes of sediments, biologically active materials and sometimes toxic compounds
are rapidly increasing. If we are to comprehend the impactof these fluxes, we must conquer the complexity of coastaltransport processes. The physical forcing of wind provides
coastal upwelling, which enriches marine ecosystems andcreates rich fisheries. Natural climate variability can havestrong impact in these systems, as it happens with El Nio,for example. Other natural or anthropogenic climate shifts
could change these dynamics with enormous consequences.
In order to solve these and other important coastal problems,
advanced technologies in sensors and observing systems, interdisciplinary research to understand the processes and theirconnections, integrated numerical models and data assimilation are needed.
New eyes from satellites and coastal radar can provide
needed observations in the small time and space scales inherent to many coastal processes. Even though the timeand space scales of the coastal processes can be small, theypresent large variability in interannual scales. Therefore,
there is a need of monitoring them over long periods of time.
Observing the system over an extended time will allow fora better determination of how the system responds to major
natural changes, enhancing our capability of predicting its behavior and its response to anthropogenic perturbations.
In studying the diverse roles of physical processes in othercoastal phenomena and the local ecosystem dynamics, accurate in-situ observations play a fundamental role. The continued development and use of moored instrumentation in physical oceanography, biology and chemistry will result in majoradvances in a number of important areas as biophysical coupling, cross-shelf transport processes, turbulent mixing processes and their parameterization in numerical ocean models, buoyancy-driven flows and fronts, sediment transport andbiogeochemical fluxes.
Turbulent mixing processes are critical to many coastal
processes. So, continued emphasis should be placed on fieldstudies of the turbulent cascade of energy. Improvements in
our knowledge of turbulence, for example by means of newly
developed microstructure profilers, will result in an important
improvement of our modeling capabilities. Besides their intrinsic interest, these studies provide the basis for comparison
with new numerical studies of these proces8ses and the development of better parameterizations of turbulent mixing. This
last, in turn, would benefit both coastal ocean research andthe use of models for practical applications.
As mentioned above, modeling plays a key role in coastal
oceanography. Operational real-time regional ocean prediction systems (see Figure 4.3) are required to support criticalactivities in the coastal environment, like navigation and marine operations, oil and pollutants dispersion control, searchand rescue, prediction of harmful algal blooms and otherecosystem or water quality phenomena. These systems require, in turn, to be supported by operational oceanographic
monitoring of oceans.
Realistic interdisciplinary models in concert with data assimilation are an essential tool for improving our understanding of complex coupled biogeochemical and physical37

Figure 4.3: Coastal models can be valuable as management tools using monitoring and data assimilation. Figure displays
examples of ocean model predictions (upper panel) of surface elevation and currents (left), surface salinity (center) and surface
temperature (right), and satellite color observations (lower panel) from GoMOOS (Gulf of Main Ocean Observing System
http://www.gomoos.org). This kind of systems, that bring together managers, industry, researchers, educators and others in acollaborative effort to establish a large-scale regional ocean observing system, can enhance, facilitate, and protect the livelihoods
and well-being of those who use the water bodies and depend on their ecosystems.

4.5 Recommendations

processes in coastal areas. Besides, given that biologicaland chemical data sets are sparse, it will permit to extend
the database through a dynamical interpolation providing aframework for detailed diagnosis of those processes. The instrument and platform development occurred during the lastyears together with the rapid evolution in numerical modeling, the development of theory and the continuous progressin communications are promising an important evolution ofthis field during the next years.

Taking geosciences to a point where answers will be given
to many of the urgent environmental questions of this new
century will demand effort and commitment of both scientific community and policy makers. Physical oceanography
plays a crucial role in the development of the ’Earth systemscience’, required to meet this challenge, as the oceans are acentral piece of the puzzle. The field itself requires a better understanding of the ocean’s behavior, its connections,interactions, feedbacks and couplings. Therefore, physicaloceanography needs further research and investment to develop, apply and evaluate more realistic models integrating
all of the processes involved, the improvement of the observational base, a better understanding of ocean processes
and a much larger interaction between ocean scientists. But

The need for a synoptic view of this environment to understand the processes that produce changes in coastal systems
presents major challenges for coastal oceanography. New
couplings of chemistry, biology and physics will be necessary to develop a better sense of them.
38

there will be, moreover, a need for further integration amonggeosciences to meet the real challenge of understanding andpredicting the environment for properly managing and sustaining it in a multi-coupled system. On the other hand, theanthropogenic influence can no longer be neglected in an integrated model in the long-term. The impact of, for example, fisheries, coastal constructions, like dikes, harbors windfarms, etc., and river management, has such a strong effect on
the coastal system that the governing socio-economic drivers
must be taken into account; if it is intended to predict such asystem.
In what follows, a summary of the physical oceanography
science needs and strategies for achievement emerging fromthis report, which can be regarded as a few recommendations
to the oceanographic community and policy makers, are highlighted.
Global Observing System
Ocean observations have always been the driver of new
knowledge and predictive capabilities in the ocean and its
basins. Despite this, the oceans remain vastly undersampled in time and space. Important progress in this aspect
has been derived, and will continue on, from the development of new observational satellite tools. Nevertheless, giventhat remote sensing from space is restricted to the ocean surface and its upper parts, sustained observation in the ocean
is required. An international effort to support sustained highquality global observations over decades must be done. Measurements of oceanographic, meteorological, hydrologic andbiogeochemical variables are necessary to meet new scientificchallenges and practical needs.
The need for a strong Global Ocean Observing System (GOOS http://ioc.unesco.org/goos/) as a component of the Global Climate Observing System (GCOS
http://www.wmo.ch/web/gcos/gcoshome.html) is clear. The
information to deal with marine related issues is needed, byscientists, governments, industry, and the general public.
This includes the effects of the ocean upon climate. A
unified global network to systematically acquire, integrate
and distribute oceanic observations is required and must be
supported.
New observing techniques and instrumentation
The success of new observing techniques and instrumentation in revealing aspects of the ocean circulation and climate
has been spectacular over the past 30 years. Good examples are the recently developed microstructure profilers thatallow the observation of, for instance, the dissipation rate,
and the ARGOS system which collects environmental datafrom autonomous platforms and delivers it to users worldwide. Improved observing techniques must continue to be
developed both to make more effective measurements of essential variables and to expand the suite of variables that canbe observed.
Data assimilation
Data assimilation can add considerable value to global ob-

serving systems by combining diverse sets of observations
with global numerical models to produce comprehensive andinternally-consistent fields. The assimilated products combine the accuracy of the observations with known geological, chemical and physical consistency and provide global
coverage inherent in the models. Therefore, advancement of
assimilation techniques to reach optimal schemes must be apriority.
Operational oceanography
An operational oceanographic near-real-time data collection, similar to the one existing for meteorology, needs tobe established. There is a need for efficient, integrated
systems for coastal and global ocean products, provided
regularly and in real-time. That system, which requires
the application of state-of-the art models, data assimilation methods, global observing and communication, would
have tremendous impact on improving coastal, open oceanand climate forecast, as well as on most of the aspectsof physical oceanography research. Experimental systems
like GODAE (Global Ocean Data Assimilation Experiment
http://www.bom.gov.au/bmrc/ocean/GODAE, see Figure 4.4)
must, therefore, make the transition from research mode tooperational GOOS and CGOOS (Coastal Global Ocean Observing System http://ioc.unesco.org/goos/cozo.htm).
Numerical modeling
A continued emphasis is needed on the development ofmodels in all their applications, and a special effort is needed
in developing models that link the different parts of the oceansystem.
Numerical models are becoming a centerpiece of our science since results of theory and observational data are often
cast into the form of numerical models. This happens either through data-assimilation or through process-model explorations of theoretical ideas. Models have proved essential
in determining the relative importance of variables in complex, nonlinear systems that have multiple feedbacks and are
the ultimate tool for prediction. Crucial physical effects arebeing now identified that have seriously limited the accuracyof model prediction in the recent past. By taking advantage
of rapid advances in computer technology, and of new data
streams from powerful observing programs, great advances
will be made. There is a need, therefore, for model and data
assimilation, development and improvement. Linked models
that tie together physical, geological, biological and/or chemical systems show great promise and should grow in importance in oceanographic research. Interactions between suchmodeling effort and field programs will aid in both designingobservation strategies and in evaluating outcomes.
Closer interaction among physical oceanographers
Overcoming the predictability barrier will require the continued development of in-situ and satellite observing systems,
improved numerical models, the assimilation of data in models, and the closer linking of the physical system to the important biogeochemical aspects of the ocean and climate. Reach39

Figure 4.4: Sea surface temperature nowcast for 5-21-2003 and one week forecast from MERCATOR mission. From 2003 to
2005, the demonstration phase of the GODAE experiment will provide a routine and real time depiction of the global ocean.
Half a dozen of operational oceanography centers will emerge in this purpose throughout the world. MERCATOR will be oneof them. The transition from the experimental phase to a truly operational one would have a tremendous impact in physicaloceanography. Fig. courtesy of MERCATOR Mission (http://www.mercator.com.fr).
• Summer schools, workshops and post-doctoral programs to encourage cross-fertilization between the different methodologies.

ing these objectives will, therefore, demand a close interaction between seagoing oceanographers, scientists concernedwith the ocean-atmosphere interface, ocean modelers, theoretical oceanographers and satellite remote-sensing scientists
that could be promoted by improving the communication andinteraction among scientists of different fields and countries.
IAPSO might play a fundamental role in this aspect. Somesuggestions are:• Encouragement of proposals using complementary approaches (observations, modeling, laboratory, theory).
Earth System Science and interdisciplinary research
As oceanography progresses and faces more often environmental problems, it becomes increasingly necessary to
formulate new research initiatives using an interdisciplinary
framework. We should facilitate closer ties and collaboration
across the geosciences.
To meet the aim of building up an ’Earth Model’ for understanding and predicting the functioning of the whole climatic
system, collaboration of experts in the traditional earth disciplines (meteorology, oceanography, hydrology) as well as in
ecology, information technology, instrumentation and complex system theory will be necessary. In this new science, the• A greater and better use of the Internet.
• Workshops that bring oceanographers from different institutions and areas of expertise together for extended
periods.
• Opportunity for investigators to make extended visits toinstitutions other than their own and to meet others withsimilar interests, but different approaches.
40

4.6 Conclusion

most challenging task is integration, as we need a vision as
integrated as possible of all the many elements of the system.
Physical oceanography must make commitments to reach thedegree of co-ordination and co-operation among geosciences
demanded by this enterprise. The IUGG and its comprised
associations have a fundamental role to play here.
Public information and communication:
The ocean plays a critical role in our everyday life and in
the future of our planet. As more people understand this andbegin to appreciate the Earth as a water planet, they will takeaction to conserve the ocean and the web of life it supports
and will give, consequently, a better support to oceanographic
scientific research. Therefore, the oceanographic community
should make an effort to improve presentation and communication of results to society and policy makers, taking special
care of avoiding misinformation and/or poor use of the information. This should not be a one-way road. In the frame of
integrated models, oceanographers must also account for social and political decisions if long-term predictions are envisaged. Communication is an important aspect in which IAPSO
can play a central role.
E-science:
A greater and better use of the possibilities of free information and communication provided by the Internet would be ofgreat benefit for geosciences.
Infrastructure:
In order to reach our aims, we need adequate updated technology. The availability of research ships requires inversion and planning. Continued enhancement of computing resources is required in order to meet the demands for climate
modeling and forecasting. Even though the power of computers is doubling every few years, the complexity of the oceans
ensures that the needs of physical oceanographers will always
be limited by computational resources. Physical oceanographers need continued access to computing resources, which
are comparable to those of the international atmospheric andengineering communities.
Human resources:
If we are to reach the goals, there must be sufficient scientists with an adequate education researching all over theworld. On the other hand, we must assure that a steady supply of experimental scientists and engineers continues alongwith modelers and theoreticians in order to keep the balance
between the different fields. As environmental problems will
increase in the next decades, future graduates should haveincreased opportunities for interdisciplinary studies both inside of and outside of the academic science community. Human resources can constitute a serious problem in developing countries, where the low number of experts (and sometimes their lack) impedes the formation of new graduates.
The degree of global expertise could be greatly enhanced by
the creation of inter-institutional PhD programs promoted by
IAPSO.

Physical oceanography has reached a challenging point where
progress in technology and the tools that this technology
make possible are allowing for a new ’look’ at the ocean. The
complexity of the ocean circulation may now be approachedwith sufficient detail to promise that significant progress will
be made on many scientifically and societally important issues during the next decade. IAPSO and the oceanographic
community should take advantage of this situation.
The great challenge of constructing an ’Earth Model’ toimprove our understanding, use and management of thePlanet for the benefit of the Human Race, in which physical oceanography will play a fundamental role, can start totruly be faced. It will become a reality if the necessary resources are available and a genuine commitment is made by
the geosciences community to reach the required level of integration and research effort. IUGG, through its actions, canplay a significant role in the realization of this vision.

4.7 Acknowledgments
The GTF committee would like to thank Alan A. Meyer for
his work on the IAPSO section of the report, and serving on
this committee for the amount of time that he was able.

Bibliography
50 Years of Ocean Discovery: National Science Foundation
1950-2000. Commission on Geosciences, Environment
and Resources (CGER), Ocean Studies Board (OSB),
National Academy Press. Washington, D.C. 2000.
Coastal Ocean Processes and Observatories: Advancing
coastal research. Coastal Ocean Processes (CoOP) Report No. 8. Technical Report. 2002.
Current Approaches to Seasonal to Interannual Climate Predictions - IRI Technical Reports 00-01, 2000
IPCC, Climate Change 2001: The scientific basis. Technicalreport, IPCC, 2001.
Global Environmental Change: Research Pathways for the
Next Decade, Committee on Global Change Research,
National Research Council. National Academy Press.
Washington, D.C.. 1999.
Global ocean science: toward an integrated approach.
Ocean Studies Board, commission on Geosciences, Environment, and Resources, National Research Council.
National Academy Press. Washington, D.C., 1999.
GODAE (Global Ocean Data Assimilation Experiment),
2001: GODAE Strategic Plan, GODAE International
Project Office.
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Ocean Circulation and Climate. Observing and Modelling
the Global Ocean. G. Siedler, J. Church and J. Gould
Eds. Academic Press. London. 2001.
Ocean Sciences at the New Millennium Report. Workshop
sponsored by the National Science Foundation throughan award to the University Corporation for AtmosphericResearch Joint Office for Science Support. Edited by
Geosciences Professional Services, Inc. 2001.
Oceanography in the Next Decade. National ResearchCouncil, Commission on Geosciences, Environment,
and Resources, Ocean Studies Board.
National
Academy Press, 202 pp., 1992.
Opportunities in Ocean Sciences: Challenges on the Horizon, Ocean Studies Board, Commission on Geosciences,Environment, and Resources, National Research Council, 1998.
Report of the Advances and Primary Research Opportunities in Physical Oceanography (APROPOS) Workshop,
Monterey, California, December 15-17, 1997.
Strategic Plan and Principles for the Global Ocean Observing System (GOOS). GOOS Report N◦ 41. IOC/INF
1091. 1998.
Exploration of the Seas: Interim Report. Ocean Studies
Board (OSB). National Academy Press. Washington,
D.C. 2003
The second report on the adequacy of the Global Observing
Systems for Climate in support of the UNFCCC. GCOS82. WMO/TD No. 1143, 2003.
The integrated, strategic design plan for the coastal observations module of the Global Observing System. GOOS
Report No. 125; IOC Information Documents Series
N1183; UNESCO 2003
Theory in Ocean Dynamics. P. B. Rhines. In The Future of
Physical Oceanography, report of the APROPOS Workshop, Monterey CA UCAR/NSF, 178pp. 1998
Towards Life and the Whole Earth; Ocean Science New Directions. Japan Marine Science and Technology Center,2002. 1942

Chapter 5International Association of Hydrological
Sciences
T. Oki5.1 Introduction —Hydrology, the forgotten earth science—

drology. Before the era of global environmental issues, human activities were excluded from the view of natural sciences. However, anthropogenic effects should not be excluded when the current Earth system is discussed, since “natural” and “real” have different meanings in this Anthropocene[Crutzen, 2002]. The “real” situation of the Earth is not “natural” anymore.
Hydrology should have the leading potential among geosciences to explore the interactions between human society
and natural earth systems. The current struggle of hydrology to realize potential achievements is reviewed, and theperspectives of hydrology are presented in this short report.

There was a statement from Prof. R. Bras at MIT [Bras andEagleson, 1987] in the 2nd US-Japan Hydrology Seminar in
Hawaii [Kayane, 1989]:
Hydrology, the science of water, has natural place
alongside oceanography, meteorology, geology,
and others as one of the geo-sciences; yet in themodern science establishment, this niche is vacant.
Why is this?
Such an awareness of the issues has been discussed repeatedly in various workshops and symposia and even publishedin a few books [Kundzewicz et al., 1987; NRC, 1991; Buras,
1997].
One of the answers to the above question is that hydrology
is too biased to engineering:

5.2 Long-term Goals
5.2.1

What is hydrology?

UNESCO defined the discipline in 1964 as:

In practice, hydrology is regarded mostly as a technological discipline rather than a science. This attitude is responsible for much poor science in hydrology, which, in turn, has led to much poor technology in applied disciplines. It is urged that thepresent offers a unique opportunity to fill the vacant niche of the science of hydrology and somesuggestions for action are offered. [Klemeŝ, 1988]

Hydrology is the science which deals with the waters of the earth, their occurrence, circulation anddistribution on the planet, their physical and chemical properties and their interactions with the physical and biological environment, including their responses to human society.
Hydrology is a field which covers the entire historyof the cycle of water on the earth.

Until recently, engineers in hydrology were forced to givesome account for demanding and sometimes unreasonable
questions from society, based on limited and uncertain information of water balances and hydrological cycles. Scientists
in hydrology tried to pursue “pure science” but not a few ofthem failed to overcome the temptation to relate their researchwith practical applications.
Here, the clue is that “pure science” and “practical engineering” should not always be exclusive, at least not in hy-

It is noteworthy that the responses to human society are included in this statement issued just before the International
Hydrological Decade, which was the first international research program on hydrology, organized by UNESCO for
1965-1974.
The recent definition [UNESCO and WMO, 1992] says hydrology is43

1. Science that deals with the waters above and below theland surfaces of the Earth, their occurrence, circulationand distribution, both in time and space, their biological, chemical and physical properties, their reaction with
their environment, including their relation to living beings.

It could also be relevant for hydrology to utilize the knowledge of water for society and human beings.
Therefore to increase the ability to:• monitor the quantity and quality,• model/simulate the flux, and

2. Science that deals with the processes governing the depletion and replenishment of the water resources of theland areas of the Earth, and treats the various phases of
the hydrological cycle.

• predict the quantity, quality, and flow of water as required to promote the hydrological sciences.
All these monitoring, modeling, simulations, and predictions should be associated with the estimates of their uncertainties and reduction of the uncertainties is one of the targets
in hydrological science.
Similar to other geo-sciences, finding another principal law
governing the movement of water is not the central themeof hydrological science. However, it does not mean there is
no opportunity that new laws in hydrological science havebeen/will be found. Because of the scaling effect and the heterogeneity of the boundary condition and/or environment of
the phenomena, theories and equations, which can be applied
to ideal, well controlled conditions, either molecular scale orlaboratory experimental scale, may not have enough capability to explain the phenomena we observe in the real field. This
demands the establishment of sophisticated systems of laws
and theories that can describe the hydrological cycles on the
Earth, considering the spatial and temporal scales and the heterogeneity.
In other words, consideration of scaling effects and heterogeneity is identifying the dominant process governing theparticular hydrological phenomena. In a sense, hydrologicalscience formed its original discipline apart from fluid dynamics and hydraulics by neglecting the conservation of momentum by defining the target phenomena with viscosity prevails
the motion and cancels the acceleration. Future hydrological science may include the detailed equations of Motion, if
needed, for better simulation/prediction of hydrological Cycles. However, full descriptions of detailed hydrological processes in the real world, even for a hill slope of 1m length,
will remain impractical and may be useless for understanding
the phenomena.
Here, “full description” indicates describing the phenomena based only on the principal physical laws with reliable
parameters, which can be estimated in the laboratory or field
experiments. The value of the parameter should be reproduced with enough accuracy when the experiments are repeated, and it is preferable the parameter can be estimatedfrom other physical parameters.
In this sense, even Darcy’s law, which is one of the basic
laws in hydrology, is not the principal physical law. Darcy’s
law requires saturated hydraulic conductivity as its parameter, but it is well known that saturated hydraulic conductivity
is various even within a one square meter field, which seems
homogeneous in terms of the density and the contents of the

The two parallel definitions are from the natural science sideand from application oriented side.
Then, which water and what hydrological cycle are excluded from the view of the current hydrological science?
These are for example:• water out of the Earth: even though water is not uniqueon this planet.
• water in the Earth: even though water may have a significant role in the motion of the mantle, and the total
amount included in the Earth could be more than that on
the surface of the Earth.
• ocean: even though more than 97% of water on the
Earth’s surface stays as oceanic water.
• atmospheric water: even though there are certain
amounts of studies on precipitation by hydrologists andthe discipline of hydrometeorology exists, generally precipitation is the given input to hydrological system on
the land surface.
• water in pipes: water cycles in purely artificial system is
not the main target of researchers in hydrology.
• organic water: even though water flow in plants is intensively examined in current hydrology, water cycle incirculatory organs is not generally dealt with by hydrologists.
From the above list, it is apparent that hydrological science
covers the niche of other disciplines by nature. On the contrary, transdisciplinary studies in these currently uninvestigated water cycles by hydrologists may have some potential
to break through the new frontier in hydrological sciences.

5.2.2

Long-term Goals in Hydrology

The ultimate objectives of the hydrology are to know:• the quantity and quality of water in a defined area, and• the inflow and outflow of water and its content to andfrom the area.
44

soil. However, it should be still better for most of the problems in hydrology to adopt Darcy’s law rather than considering water flow through each microscopic pore in the soil
layers. Therefore, integrated theories/models/equations corresponding to the temporal and spatial scales and heterogeneity will be used to describe the phenomena.

A similar statement was included in the Plan of Implementation from the World Summit on Sustainable Development
held in Johannesburg in August 2002, in article 6 of Chapter II Poverty Eradication. In addition to that, the access tobasic sanitation was also focused in article 7. In the WSSD
Plan of Implementation, further research and development onwater related sciences was urged together with researches onenergy technologies, bio-technology, environmental management, marine resources, and sustainable development. All ofthese international vision/action statements aim to alleviate
Poverty, particularly in developing countries.
Under such a movement, what kind of researches can be offered from the scientific community in order to contribute tosolve the current water related issues and the anticipated “water crisis” in the near future in the world? What are the scientifically excellent and practically/socially relevant research
topics?
Over the last decade it has become increasingly clear that
if we are to face the water challenges of the future, we mustview the Earth as a single, though highly complex, integrated
system. The atmosphere, the hydrosphere and the biosphere
extend throughout the globe. They are very dynamic andhighly interactive. Changes that occur in one location can
influence the environment somewhere else in ways that are
not always expected and are frequently poorly understood.
The complicated interactions between the physical and human systems are equally critical. The scientific and technicalcommunity has a very important role to play in this regard.
This role is not only related to scientific monitoring, analysis, and interpretation, but also to guiding future policies andaction programs. Effective water management is not purely apolitical problem, a scientific problem, a technological problem, nor a managerial problem; it is a complex problem thatdemands interaction between all of these areas. It is clear thatto assuage the impending water crisis, cooperation between
the scientific disciplines, as well as the scientific and water
policy arenas, must dramatically improve. A directed effort
must be taken now to improve the recognition of the impending water crisis by all stakeholders and to improve the understanding of the components involved with the natural system
and allocation of its resources.

5.3 Short-term Goals
5.3.1

Current Demands on Hydrology

Conservative projections, based on current information about
population growth rates, pollution, salinization, waterlogging
and groundwater overdraft, all indicate a high increase in thenumber of countries that will experience significant water
stress and scarcity in the near future. The United Nations
system presented a Comprehensive Assessment of the Freshwater Resources of the World [UN et al., 1997] to the nineteenth Special Session of the United Nations General Assembly in 1997. This assessment made it clear that a ”businessas-usual” approach to water allocation and management is notsustainable.
The situation for a majority of the world’s population has
not improved since the Comprehensive Assessment of theFreshwater Resources of the World was presented to theUnited Nations in 1997. Still, over a billion people lack access to safe drinking water, and almost 3 billion lack proper
sanitation. Millions of people die each year from water related diseases, and there are no clear indications that thesetrends will improve in the near future. The increased use ofpollutants associated with the technological development ofcountries with evolving market economies, life-style changes
all over the world and the increased need to develop sustainable water resources and infrastructure for growing populations all contribute to the urgency associated with advancing
hydrological sciences and water management strategies. Increased competition among and within sectors calls for strategies that will help to balance water use for the multitude of
purposes required by humans, while protecting the integrityof the ecosystems. Some of the statistics are staggering. By
2020, water use is expected to increase by 40%, and 17%
more water will be required for food production to meet theneeds of the world’s growing population.
In the millennium declaration (55.2), which was adopted
by the General Assembly of the United Nations in September
2000, it was stated in section 19;

5.3.2

Contribution to solve the world watercrisisIn preparation for WRAP (Water Resources Application
Project) under GEWEX (Global Energy and Water Cycle Experiment) Hydrometeorological Experiments Panel (GHP),
these items were identified to contribute to solve the current
water related issues. These are to provide

To halve, by the year 2015, the proportion of theworld’s people whose income is less than one dollar a day and the proportion of people who sufferfrom hunger and, by the same date, to halve theproportion of people who are unable to reach or toafford safe drinking water.

• reliable information on– past and current global hydrological cycles,45

– near-real time to seasonal prediction on naturalvariability of climate, such as El Niño and La Niña,andStatistical approaches may be useful to give predictions, aswell. Even though that could be only for ad-hoc applications,
new insights in tele-connection of hydro-climatology may befound from the sensitivity tests of the statistical models.
The prediction of climate change, particularly global
warming itself, is attracting a lot of attention. Since mostof the reliable predictions of hydrological cycles in the future
are estimated by GCM simulations, the way to interpret ortransform the GCM estimates to water resources assessment
is another key issue. Down-scaling the coarse spatial (andtemporal) resolution of GCM estimates is one of the scientificproblems, but there are many technical issues, such as bias
reduction of GCM estimates and the reproductivity of statistical characteristics particularly on precipitation simulated in
GCMs. How to extract robust information from GCM predictions on water cycles in the future should be given more
attention.
As for the human dimension side, how to draw the prospect
on water demand, withdrawals, and consumption is basicallyneeded. They are generally estimated with the outlook of the
future growth of population, economy, etc., but it is very difficult to fully include the impact of innovation in technology
and change in policy. Therefore, somehow scenarios should
be set to assess the future demand in water resources. Even
though socio-economic scenarios are used in the projectionof future climate in IPCC, most of them do not include thefeed back mechanism of how water shortages suppress various social activities and economical growth.
There is no guarantee that complex models will provide
better results, but interactive modeling on water consists ofnatural climate system, hydrological cycles, anthropogenic
activities such as irrigation, regulation by reservoirs, landusechange, etc., may provide new insights in the global water resources assessments. Virtual water trade, how much domestic
water resources are saved by international trade of products,
may be incorporated with the modeling of “real water.”
An improved understanding of the operation of hydrological processes at the local scale is also required; e.g., in orderto understand how land-use change and management affectwater resources and also to downscale from global models.
Regional studies should also be important for policy making, and it is recommended that information on water demand
and water management should also be collected when hydroclimatic regional studies will be taken. Based on the regional
studies, science-based decision-making tools should be developed, which can cooperate with the uncertainties includedin each component of prediction.
Global studies are also expected to provide useful information for regional studies. In practice, there are many placesin the world where global datasets of precipitation, landuse,
soil types, etc., are the only sources available for hydroclimatological studies. Therefore, the applicabilities of thisinformation on integrated water resources management on
local/regional scales will be examined under the Project for– the change in hydrological cycles under climatechange conditions, such as global warming,• quantitative estimates of how much water is (and will be)really available for further water withdrawal for humanbeings, and• alternative measures to be taken in order to secure thewater supply to meet the water demand.
The first three items under the category of “provide reliable dataset” can be done by natural scientific approaches,
however, the other two should require inter-disciplinary
collaboration between natural and social sciences. The
planned Global Water System Project by WCRP (World Climate Research Programme), IGBP (International GeosphereBiosphere Programme), IHDP (International Human Dimensions Programme), and DIVERSITAS (An International Programme of Biodiversity Science) will be an appropriate platform to pursue such a collaborative research(http://www.gwsp.org/).
To provide a reliable dataset of past and current global hydrological cycles, continuation of observational network, research and development on new observational measure, and”data rescue” of historical records are important. Satellite
remote sensing could be the only hope to provide global coverage of hydro-climatic information, however, ground based
network should be held by all means to secure the reliability of global observation. Since there are not a few historical
records that are not digitized but cover more than hundredyears, database development of these data is also important.
Global offline simulation of LSMs (land surface models)can provide global flux and balances of water, energy, andeven more (such as carbon). However, the accuracy of the estimates is subject to the accuracy of LSM itself, forcing data,
model parameters, and temporal and spatial scales employed.
Therefore the uncertainties associated with the global estimates by LSMs will be examined in the GSWP (Global Soil
Wetness Project) under GEWEX/GLASS, Global Land Atmosphere System Study(http://hydro.iis.u-tokyo.ac.jp/GLASS/).
There are many researches to improve providing seasonal
prediction of water cycles. It seems widely believed thatthe improvement in giving boundary conditions over land
will improve the accuracy of seasonal prediction of water
cycles over land. Usage of better LSMs in GCMs andsatellite derived surface conditions, such as soil moisture,
may contribute for the improvement, however, how land surface conditions affect the prediction of hydrological cycles
over land should also be investigated. For that purpose, the
GLACE (Global Land-Atmosphere Coupling Experiment)
under GEWEX/GLASS is planned.
46

Prediction of Ungauged Basins (PUB) of IAHS (International
Association of Hydrological Sciences).

5.3.3

The most critical ”bottlenecks,” or barriers to the advancement of hydrological science, as well as some solutions necessary to overcome the obstacles, are described below. Organizational and technical bottlenecks are presented in the recommendation section.

IAHS Hydrology 2020 Working GroupThe Hydrology 2020 group

5.3.4(http://hydro.iis.u-tokyo.ac.jp/H2020/)

Scientific Bottlenecks

The Hydrology 2020 group has recognized many fundamental bottlenecks within hydrological sciences that must be reconciled in order for hydrology to meet the water scarcity andpollution challenges of the next few decades. These scientificbottlenecks include persistent obstacles that cut across many
disciplines, such as data integration, scaling, and numericalrepresentation of complex processes. However, some of thesebottlenecks are associated with the lack of understanding offundamental processes, systems, or cycles that are most germane to hydrologists, such as the water cycle and the vadosezone. For some problems, the theory and approaches within
individual subdisciplines are quite advanced, but the links toneighboring disciplines are often not well established. The
individual scientific bottlenecks are described below.

was assembled by IAHS to assess how the discipline of hydrology should evolve to meet the world water challenges thatare expected to prevail by 2020. The 2020 Group would follow the pattern established by the Hydrology 2000 Working
Group which was set up in Hamburg in 1983 and reported in
Vancouver in 1987 [Kundzewicz et al., 1987].
Nine commissions under IAHS nominated the names of
two young hydrologists who are this year aged 35 or less,considering region and gender in the choice, and the presidentof IAHS determined that one of these two be the member ofthe group. WMO and UNESCO nominated one each, and thechair of the group was separately nominated by the presidentof IAHS, as well. The group was authorized at the plenary
meeting of IAHS general assembly at Maastricht in 2001 andexpected to report their vision of hydrology in 2020 at the
IAHS general assembly meeting in 2005 with articles on an
IAHS publication (“redbook”).
The group held face-to-face meetings twice in 2001, defined their mission, and drew their road map to synthesize
their visions. At first, they looked back 20 years ago, reviewed what were the most relevant research achievementsin those days, and defined the changes since then in each subdiscipline in hydrology. Then, they examined the 20 years
ahead with questions like:

Incomplete Understanding of Hydrological Processes
Deficiencies in our understanding of many of the hydrologicalprocesses and systems greatly handicap our efforts to guidewater resource planning, to predict hydrologic extremes, andto predict contaminant migration.
For example, as crucial as the water cycle is to humanand ecosystem existence, there are still many gaps in the understanding of the individual components that comprise thewater cycle, as well as the interactions between these components. Additionally, the vadose zone, which supports ouragriculture, serves as the repository for most of our municipal, industrial and government wastes and contaminants, andsupports our infrastructure, plays a crucial role in both thewater cycle and in contaminant hydrology. In spite of its importance, the understanding and prediction of flow and transport of water and contaminants through the vadose zone andacross the upper (soil-air) and lower (groundwater) boundaries are inadequate.
Improved understanding of the hydrological processes andsystem components can be obtained through nested and coupled experiments replete with field measurements using several techniques, remote sensing measurements, process investigation, and modeling. Improved observations of water
vapor, clouds, precipitation, evaporation, surface and subsurface runoff, groundwater, soil moisture, snow and ice using
new technologies and networks collected over various spatial and temporal scales are needed to improve our understanding of the water cycle. These measurements must haveenhanced resolution, increased accuracy, and be maintained
for long time periods relative to the currently available data

• what will be the hydrology in 2020 under “business as
usual” scenario?
• what shall be the hydrology in 2020?
• what should be done now to achieve the preferable situation of hydrology in 2020?
The group prepared their intermediate report to stimulate
discussions with the general audience of IAHS/IUGG in theiropen workshop in Sapporo in July 2003.
The intermediate report consists of:• uniqueness of hydrology• advances in technology• needs of society• critical bottlenecks
The drafts of the latter two chapters are included in this report.
47

Scale problems

acquisition schemes. These measurements must be coupledwith process studies of the individual components as well as
the linkages between components over various spatiotemporal scales. The measurements and process studies must be
incorporated into improved models (see below). Establishingcoordinated and linked field observations with remote sensing
data and modeling efforts over a variety of spatial and temporal scales is necessary for an improved understanding andprediction of water cycle, hydrological extremes, and contaminant infiltration.
Successful implementation of the nested and coupled field
experiments will require advances in our approaches to modeling, data integration, and scaling. These topics are also current scientific bottlenecks, as described below.

Issues related to scale are persistent across all aspects ofhydrological sciences as well as in many other disciplines.
Other topics requiring additional research include investigation of dominant processes and interactions between processes that occur at different spatial scales, and reconciling the different spatial scales associated with measurements,
physical processes and numerical models.

5.4 Recommendations
5.4.1

Organizational Issue

Water issues are complex, as water acts as a link between various water uses, land use and ecosystems. Calls are often madefor integrated water resources management strategies, such as
basin-wide hydrosolaridarity, which focuses on water allocation principles based on equity and efficiency. However, suchconcepts are still poorly defined and even more poorly understood. It is clear that effective policies are needed to strikecompromises among competing water uses, to develop sustainable water resource plans, to alleviate and mitigate pollution, and to allay water-related disasters. These policies must
be driven by scientific knowledge and scientifically based recommendations, which stem from appropriately directed hydrological research and adequate funding.
Although water quality and resource management cut
across political and national boundaries, no strong and wellfunded intergovernmental global hydrological organization
exists that can coordinate and fund research and operational
efforts within the broad range of hydrological sciences. A
global hydrological intergovernmental organization is needed
to serve as the authoritative scientific voice of hydrology andalso to organize research efforts toward world water problems. It could have a role in facilitating integrated approaches
to water development and management and offer a capacity
to provide advisory services and implement and strengthen
technical cooperation and investment projects targeting critical areas of water resource management. Scientific resultsmust be translated into action-oriented recommendations sothat they can be used in national and international policy evaluation, formulation, and planning. These recommendations
should be formulated in terms that are clear, specific and realistic. With substantial funds and commitment, this organization could be developed anew, or the hydrology and water management sections of WMO/UNSECO and other UN
agencies could be combined and expanded to meet the organizational needs of the hydrological sciences. The primary
responsibilities of this global organization would include:

Modeling
Many numerical models are based on hydrological principles; these models range from flow and transport in the
groundwater to global circulation models. In most cases, acombination of both incomplete theory and data exist. Because of these inadequacies, many different modeling approaches have been developed, ranging from deterministic
to stochastic and from data-driven to physics-based. Modeling should continue to be a research topic, with more emphasis on uncertainty assessment, improved parameterization and data assimilation approaches, standardized validation procedures, improved frameworks for incorporating indirect data (tracers, geophysics, remote sensing, etc.) and improved numerical representation of coupled processes (suchas hydrogeological-biogeochemical) and systems (such as
land and atmosphere).

Data Integration/Calibration
Various data sets, such as tracers, ground-based geophysics,
and remote Sensing, are becoming increasingly available foruse in hydrological studies. More research is needed to fully
develop the potential that these tools have for assisting withhydrological problems. Many current obstacles are associated with improving the accuracy and resolution of the geophysical and remote sensing measurements. With both datatypes, a better understanding of data integration approaches
is needed to enable routine calibration (often using data setsthat are collected at different spatial scales) or to facilitate acomprehensive interpretation. With both ground-based geophysics and remote sensing data sets, we should strive to
move beyond site-specific inference based on spatial patterns
toward an improved understanding of the physics, so that thedata can be used to more generally and quantitatively estimatehydrological-climatological parameters of interest.

Water policy : The organization would both coordinate andcontribute to water policy activities, serving a the central spokes-organization for global hydrology and water
management;
48

Coordinated Research Management : A central focus of
the organization would be to develop, fund and coordinate long-term research programs. Included in this task
is the coordination of research programs that are developed by individual countries and organizations in orderto most effectively tackle the existing scientific challenges.

ten in the face of incomplete fundamental theory, using
currently available approaches and instrumentation.
There have been unsuccessful attempts to develop such a
global organization in the past. The attempts met with resistance, not only because of protectionism among existing organizations, but because of the lack of willingness to support
additional intergovernmental organizations among national
funding agencies. Water issues are far too often considered
to be part of national security with a strong unwillingness toopen up for international cooperation. However, the current
situation, typified by a lack of coordination and the duplication of efforts, is not an effective way to handle the challenges
that we face. Water quality and quantity trends are not auspicious, and no clear solutions are on the horizon. We urge thehydrological sciences and water policy communities to reconsider the issue of developing a global hydrological intergovernmental organization that would serve as the authoritative
scientific voice of hydrology and to organize research efforts
toward world water problems.

Testing Centers : The organization would be responsible
for establishing linked testing centers/areas that scientists can use to test models and approaches, to sharedata/instrumentation, and to train students or representatives from developing countries. The centers should
work together to establish acceptable data standards,
formats and calibration approaches and to coordinate
long-term data acquisition, archiving, and dissemination. These centers are currently critically needed, yet
are too costly to develop by individual researchers or
small groups of researchers.
Education/Outreach : The organization should establish
standards and advocate public education in hydrologicalsciences. The organization should oversee outreach efforts to engage young and bright scientists into the discipline, and to make formal connections between the many
sub-disciplines that interact with hydrology.

5.4.2

Practical/Technological Issues

There are several issues where funding or commitment is
the major impediment to progress rather than developmentof new theory. These practical/technological bottlenecks arebriefly described below.

Public Awareness : An important component of the organization will be to raise public awareness about the impending water crisis in a manner similar to how awareness was raised about climate change and ozone depletion issues. Greater awareness translates into more political support and more funding geared toward hydrological sciences.

Inexpensive access to data : Many of these obstacles haveto do with acquisition of and access to data. In order tobetter assess and manage the world’s water supplies andprevent hydrological catastrophes, free access to current
hydrological data is needed, concomitant with long-term
commitment to establishing and maintaining monitoring
networks.

Technology Transfer and Capacity Building : The globalhydrological organization would strive to strike a balance between supporting fundamental research and devoting resources toward capacity building and towardfinding practical solutions to hydrological and water
management problems in developing countries. In many
locations, there is a current disconnect between thestate-of-the-art in hydrology (represented by complex
research advances) and the state-of-the-practice (the tendency to implement the developed approaches in thefield). While many hydrologists in developed nations
focus on issues such as resolution, uncertainty, and accuracy of advanced prediction/estimation approaches,
those in less developed nations are enthusiastic about,for example, the development and dissemination of inexpensive treadle pumps that can deliver irrigation water to their crops using human (cycling) power. Thus, inaddition to support of fundamental research (which will
be described below), there also needs to be support andguidance for well-trained hydrologists and water managers who can focus on solving practical solutions, of-

New Sensors : New sensors are needed to obtain improved
data sets. Although microsensors that are cheap, small,
automated, smart, injectable and innocuous are currently
being developed in engineering and biomedical fields,
development of such sensors for hydrological sciences
has been sluggish. On the other end of the spatial scale,satellite sensors, which have hydrological applications
as the primary goal, should be developed. These sensors should be improved to offer higher spatial resolution over more specific spectral bands, and should havefaster return periods.
Water Database development and management :Another practical bottleneck within the hydrologicalcommunity is the lack of a worldwide water resources
database. Water resources cannot be managed unless
we know where they are, in what quantity and quality,and how variable they are likely to be in the future.
Development and maintenance of a database using49

high quality data is crucial for assessing global water
resources and proper planning for their conservation.
The Global Runoff Data Center is currently establishinga data base that compiles freshwater fluxes and longterm mean monthly discharges from selected monitoring
stations. Databases such as this should be expanded toinclude complete information of all significant world
aquifers that includes information about capacity, waterbalances, purpose, and type of runoff control andassociated GIS coordinates.

Science also has a role in the development of new technologies, such as remote sensing and Geographical Information Systems (GIS) and demonstrate the applications of suchtechnologies to managers. They can offer the potential of increasing the capacity for monitoring of the relevant elements
at a moderate price. Information must then be made available.
It must be recognized, however, that such technologies areoften associated with initial training and technology needs,
especially in developing countries. Many international organizations will have to play a more pro-active and supportingrole in the endeavor to promote the use of such technologies,
and support the necessary technological exchange and training associated with them. Strong partnerships between academic institutions in developed and developing countries are
an important aspect, and should be promoted by governments
and international organizations.

Technologies for Developing Countries : Development ofsmall-scale technologies and approaches for dealing
with (often nation-specific) water supply and sanitation
issues could dramatically improve conditions in many
developing countries. Although development and deployment of such technologies could be performed withminimal funds, a global commitment is needed to both
identify the needs and to organize the effort.

5.5.2

Scientific projects need increasingly try to respond to, or atleast be linked to, issues relevant to socio-economic development. This is important, as there are signs of declining
respect for science and scientists over recent years from policy and decision-makers. More than two thousand years ago,
Socrates stated that “There is only one evil for humanity – ignorance.” Political ignorance is indeed dangerous, but probably some of this declining respect could partly be attributed
to the inability of scientists to present relevant informationand guidance in response to emerging issues, as well as in aform appropriate for policy and decision making in broader
terms. To provide “yes or no” answers is difficult, but the
precautionary principle, one of the Rio Principles, provide atool where the “best guess” approach can be applicable.
Hydrological sciences are no exception, and it can evenbe argued that other scientific disciplines are more active
in providing policy guidance in this field, which is sometimes a matter of serious concern. A problem, which often
arises, is that policy-makers within water management are
frequently asking long-term questions, while many scientificprogrammes are restrained by short-term funding. Despite
such limitations, scientist involved in such programmes canintensify their efforts to enhance the visibility and applicability of scientific results by using pro-active ways of communicating them and by better addressing issues and provide
guidance in response to specific societal needs.
In the international scientific debate (on water as well as onother issues) there is a tendency among scientists (including
those dealing with water) to give to much weight to their own
area of expertise. It is assumed that if we only are able todo this or that research-project the world would be in better
shape. Still, the improvements are forthcoming. While many
scientists think that good research results almost automatically permeate into policy this is seldom (if ever!) the case.
Rather, if we are to understand why certain issues are high-

5.5 Social Benefits
5.5.1

Bridging the communication gap

Science as part of capacity building andgovernance

The lack of financial resources in the water sector is only one
aspect of the problem. There are other aspects that are equallyimportant. Referring to Chapter 18 of Agenda 21, it is statedthat:“In creating the enabling environment”. . . “the roleof governments includes mobilization of financial
and human resources, legislation, standard setting
and other regulatory functions, monitoring and assessment of the use of water and land resources andcreating the opportunities for public participation.”
The role of science is implicitly a part of this. To havea fundamental knowledge base is crucial. This can be tostrengthen international co-operation in studying processes
related to the Earth’s atmosphere, hydrosphere, biosphere andgeosphere as a way to strengthen our understanding of water resources and the movement of water through the systems. But it is also essential to develop viable and scientifically based solutions to current and potential future problems. Although understanding the interconnections between
the different systems of the Earth is recognized as being essential, it remains a sad fact that they are often dealt with independently of each other, not least in the scientific community. Promoting exchange of knowledge and ideas throughimproved communication among experts belonging to thevarious disciplines concerned will be a continuous challengeahead. Scientists must dare to leave their compartmentalized
thinking and policymakers must encourage and promote suchdialogues.
50

lighted and others are not we should analyze the actual policy
process and what is decisive in that process. Communication
strategies need to be formulated that would allow scientists
to identify better communications routes to “market” their results. Otherwise our understanding will remain limited withregards to why certain aspects or research, which are highlighted by international water scientists, are incorporated in
the policy of states and international organizations and why
others are not.
It seems imperative for the water specialists of the world toincorporate issues such political feasibility, ideology and cultural aspects into their analysis. The politics of water is not
only about politicians, but also deals with how water specialists interact with government agencies, international organizations and NGOs.

5.5.3

that could be used as a fundamental base for stakeholder discussions, interactions and conflict reconciliation.

5.5.4

Recommendations for future actions –filling the gaps

The future will present us with many challenges that we, thenext generation of scientist and policy makers, must handle.
Some of them are already known, others will emerge. What
will be the issues 1, 5, 10 years into the future?
Strong leadership is essential, based on both a positive vision on what can be achieved, but also equally important onlong term persistence, not least within science. This leadership must be well informed. Only if the scientific communities work together with policy and decision-makers can water issues be successfully addressed. An integrated approach
to freshwater management is the way forward as it offers
the means of reconciling competing demands with dwindling
supplies and a framework in which hard choices, and priorities, can be made, and effective responsive action taken.
We would like, in this paper, to present some points that
we feel need to be considered to facilitate further progress:

Develop a scientifically based policy language

There are certain concepts that can be developed to respond to
the need of policymakers while being firmly based on scientific understanding and knowledge. Such innovative concepts
can help to progress thinking and act as catalyst for more progressive policy making – responding to the needs of people
while recognizing the boundaries set by the hydrological situation at each given point. Some examples are presented here:
The concept of “sanctioned discourse” essentially refers anormative paradigm within which certain hypothesis might
be raised why others may not. Thus, the sanctioned discourse
sets the “boundaries” for what is politically feasible to do.
For example, if water scientists in a water scarce region haveagreed that the rational way to allocate the water would beto decrease the amounts of water being allocated to irrigatedagriculture. Still, this is not being done, in spite of scientists
preaching it. Why? It is argued that this is so since politicians
have to act within a limited arena in which they, in this casemight be heavily influenced by a strong farming lobby thatpressure them to maintain existing allocations to agriculture.
Thus, the sanctioned discourse sets the boundaries for action
and thereby deter the politicians to act on the advise of thescientists.
The Stockholm International Water Institute has developed
a concept called “Hydrosolidarity.” Hydrosolidarity could
be developed into a commonly accepted framework and thus
provide guidelines for stakeholder interactions and problem
solving in a river basin. Rather than offering a universally
agreed set of principles, the hydrosolidarity concept should bebased upon what could be called commonly accepted thinking in relation to basic needs of different stakeholders withina basin, where the joint water resource has to be shared between both societal activities and vital ecosystem functions.
Besides that, it should offer a set of recommendations linked
not only to principles and norms but also to legislative and enforcement aspects of water management – recommendations• Knowledge and understanding of water issues is essential and must be further encouraged. National and international information networks, using modern technologies, must be strengthened. This is especially crucial
in many developing countries, where international assistance needs to be enhanced;• Efforts should be directed at facilitating the international
exchange of hydrological and related data and products,
so that global studies of freshwater resources and its
links to socio-economic and environmental issues canbe conducted and useful results produced of benefit tohumankind;• Scientific results must be translated into action-oriented
recommendations so that they can be used in national
and international policy evaluation, formulation, andplanning. These should be formulated as clear, specificand measurable goals. This is crucial if the scientificcommunity is to strengthen their credibility and further
enhance the possibility of receiving financial support forwhat are sometimes costly long term projects;• The scientific community has to find innovative waysof improving collaboration among scientific disciplines,
and with new important actors such as the private sector;• International, regional and national organizations should
be encouraged to find innovative ways to strengthen cooperation among countries which share river basins oraquifers, in particular through bilateral or other intergovernmental mechanisms. This includes the development
51

IAHS Hydrology 2020 Working Group

of agreements to share data and other information, andjoint scientific studies of shared resources;

Name
Jeanna Balonishnikova• International organizations, including within the scientific community, must, within their mandate, continue tobe well focussed and action oriented and, in particular,enhance their efforts to strengthen the capacity of many
developing countries to deal with complex environmental and socio-economic issues.

Wolfgang Diernhofer
Pierre Etchevers
Stewart Franks
Guobin Fu
Kate Heal
Susan Hubbard
Harouna Karambiri
Johan Kuylenstierna
Taikan Oki
Stephan UhlenbrookCaterina Valeo

5.6 Conclusions
According to the paradigm shift of research in natural sciences, it is the era for geosciences to study the real situationof the Earth, including the various impact of anthropogenic
activities. Water cycles are among the most exposed nature
and are vulnerable to human impacts. Therefore, hydrological science should deal with water cycles on the Earth, theirimpact on human society, and the anthropogenic impact on
the water cycles on the Earth. Regional characteristics andhistorical circumstances should be considered particularly inthe field of hydrological sciences.
The ultimate goal of the hydrological science is to increase
the ability of monitoring, modeling, and predicting the quantity and quality of water and their input/output to the system.
The outcomes of hydrological researches should have the capability to be used as a tool to know, to estimate, to understand, and to assess the water cycles on the Earth on various
temporal and spatial scales by other scientific disciplines, thegeneral public, and even by decision makers.
Scientifically excellent research and socially relevant research are not necessarily exclusive, and recent situations anticipating world water crisis gives/widens a lot of opportunities that excellent scientific research can contribute to solve
practical problems. International and interdisciplinary frame
works are also prepared to promote the hydrological sciences.
More collaborations within hydrological sciences and withother disciplines is crucial, and formulating a system of hydrological sciences philosophically and also institutionallyshould be required in coming years.

Country
RussiaUkraineAustria
FranceAustralia
China
UK
USA
Burkina Faso
SwedenJapan
Germany
Canadalead authorshipbottle necks
social benefits
editorBibliography
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Buras, Nathan, Reflections on hydrology’ science and practice, American Geophysical Union, 1997.
Crutzen, P. J., Geology of mankind - the anthropocene, Nature, 415, 23, 2002.
Kayane, Isamu, Current status of researches on hydrological cycle and water balance, In Hydrological cycles andWater Balances, volume 167 of Meterological Monograph,pages 1–20. Meteorological Society of Japan, 1989, (inJapanese).
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28, 1988.
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Webb, editors, Hydrology 2000, Number 171 in IAHS
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52

Chapter 6

International Association of Geodesy
L. Sánchez

6.1 Introduction

The coordinates on the Earth’s surface change in time due
to geodynamic processes (plate tectonics, earthquakes, fluid
displacements, etc.), Earth rotation and gravity field variations. Therefore, the position of a point must be complemented by a reference date, the origin of the fourth coordinate: the time.
Geodesy performs its tasks through collection, analysis andmodelling of observation data. Availability and quality arestrongly related to the technological advances in measurement and processing techniques. The precision level of thegeodetic observations achieved today forces us to develop adequate analysis criteria and to improve theory. This forms a
new basis to refine the measurement techniques. The ultimate
goal is the best representation of the figure, rotation (or orientation) and gravity field of the Earth and planets, together
with their temporal variations. This on going cycle leads thegeodesists to explore the actions of other geosciences and toaccomplish a closed feedback, the final purpose of which is
the welfare of mankind.
Almost every human activity requires a graphical or digital
representation of the Earth. As a consequence, an adequate
reference platform (coordinate definition), primary productsof geodesy, constitute the fundament to formulate and to execute a big variety of projects (planning and development, engineering, communications, navigation, natural hazard mitigation, energetic resources exploration, etc). In this way,
geodesy is also engaged in facilitating and making understandable its procedures to the ”every day” users, in order
to intensify the reciprocal benefits.
This document outlines the most important activities andprocedures, the geodesists under the umbrella of the International Association of Geodesy (IAG) wish to implement in the
coming years to reach the new goals that the state-of-the-art
imposes to geodesy under the global policy of achieving the
maximum benefit for the scientific community and society ingeneral.
The completion of this document would not be possible
without the kind help of the members of the Planning Group

Geodesy is classically defined as ”the science of the measurement and mapping of the Earth’s surface” (Helmert, 1880).
This definition includes ”the determination of the Earth’s external gravity field,” and it is complemented by the new concept of the temporal variations of both surface and gravity
field of the Earth, i. e. ”four-dimensional Geodesy” (Torge,
2001). These activities are also extended to the study of othercelestial bodies (e. g., planets and natural satellites).
The study of the gravity field leads to the determination of
the geoid. It is the main equipotential surface of the Earth’s
gravity field and would coincide with the ocean surface without ocean currents and other disturbances, i. e., with the hypothetical sea surface. It is the natural reference to define thevertical position: the height. It is also defined as the physical(or gravimetric) reference system. With its determination the
representation of 70% of the Earth’s surface (the oceans) isachieved.
The representation of the Earth’s solid surface is accomplished point-wise by the coordinates of control points. These
coordinates can be expressed as a three-dimensional positionin Euclidean space [X, Y, Z], or as a combination of curvilinear surface coordinates [Latitude (ϕ), Longitude (λ)] withthe vertical position [height (h)]. Since the currently available techniques to determine coordinates on the Earth’s surface involve the observation of celestial bodies (natural andartificial satellites, extragalactic radio sources, etc.), the coordinates are defined according to conventional reference systems, which are implemented by two levels: a celestial reference system to describe the Earth’s orientation in space and,
consequently, its relative position and orientation with respect
to the observed celestial bodies, and a terrestrial reference
system to describe the position of the detailed surface withrespect to the Earth’s body. The connection between celestial
and terrestrial reference systems is given by the Earth rotation parameters (precession, nutation, polar motion, siderial
time and length of day). The two reference systems are also
known as geometric reference systems.
53

Short term prioritiesof the IGGOS project (see below), who have supplied all theirvaluable material, and many geodesists who answered a survey questionnaire designed by the IUGG’s working group
Geosciences: The Future. This support is greatly appreciated.

1. Integrating different techniques, models and approaches to achieve a better consistency, long-term
reliability and understanding of geodetic, geophysical, geodynamical and global change processes: The
use of space techniques in geodesy complemented byterrestrial and airborne methods allows us, firstly, to collect large data sets, which are global, i.e., their coverage over the world is homogeneous and consistent, andsecondly, generate time series of measurements withinreasonable intervals and with a reasonable repeat period to know in more detail the (temporal) characteristics of the Earth as an unique dynamic system. Examples of the usefulness of space geodetic techniques
are: Direct and precise measurement of the continental
tectonic plates movements with Very Long Baseline Interferometry (VLBI), Global Positioning System (GPS),and Satellite Laser Ranging (SLR). Quantification ofsmall Earth crust displacements in seismic/volcano areasusing GPS continuously observing stations. Monitoring of superficial deformation, displacement and stressaccumulations in seismic/volcano areas using interferometric synthetic aperture radar images (mission InSAR)
combined with satellite positioning. Study of the interaction between atmosphere and solid Earth by monitoring length of day and polar motion. Observation of the
Earth’s masses redistribution, including postglacial rebound, ocean circulation, deformation due to the mass
exchange between atmosphere, oceans, ice and solid
Earth, etc. with the new gravity satellite missions. Analysis of the sea level variations using satellite altimetry,
including ocean circulation and its effects in global climate events, such as El Niño. Table 1 list the relevant
space-geodetic techniques and their achievements. This
list is far from complete, but it gives a general idea about
the challenges that the geodesists have to face in the next
decade(s).

6.2 A view of the future of research inGeodesy
The technological revolution in the second half of the twentieth century has strongly influenced the development ofgeodesy. In particular, the advances of artificial satellites andspace-geodetic measurement techniques made it possible toconceive the Earth as an unique dynamical system. Nowadays, it is possible to acquire large observation data sets withhigh precision and resolution in space and time, where the influences of the physics of the Earth’s interior, the interaction
with Sun, Moon and planets, and the relationship between
solid Earth, ice, oceans and atmosphere are identifiable. The
precision of the modern observational data asks for the improvement of the theoretical models. High precision measurements and theory lead geodesy into the 1 ppb - accuracy
level. Our future activities are aiming at this level, to keep
it consistent over long time periods, and to make it available
and useful to society.

6.2.1

Long term focus for Geodesy

To attain a better understanding of the functioning of ourplanet and to increase the welfare of Mankind
The shape of the Earth’s surface and its changes are produced not only by the Earth’s rotation and gravity field, butalso by the interaction of diverse phenomena as a response to
the dynamics of the Earth as an integrated system. Amongthese phenomena one can name the convection processes inthe Earth’s interior (with plate motion, crustal deformation,
earthquakes, volcano eruptions), exogenic forces (such astides, solar radiation, winds, and weather), tectonic processes(mountain building, faulting, sedimentation) and the interaction between solid Earth, ice, oceans and atmosphere (sealevel rise and fall, tides, circulation and eddy motion in theoceans, ice sheet defrost). These phenomena determine theenvironmental conditions of the Earth. In this way, geodesy,as the geoscience in charge of the representation of the Earth’s
surface, provides direct measurements of these phenomena.
Its procedures and products provide the strategic tools to continue, improve and preserve human life on this planet.

6.2.2

2. Consistent modelling of observable signals of the
Earth’s system: Modern geodetic observing procedures
are mainly based on space techniques (VLBI, satellite
positioning systems, satellite altimetry, satellite gravity
missions), which provide global orientation, and are affected by the same physical (e. g., atmospherical) factors. Often the processing and analysis of the observed
data is carried out ”independently” using different standards and models. To take maximum benefit of these
data, i. e., to produce consistent information, it is necessary to use one and the same fundamental reference system, which unifies constants, standards, geometric andgravitational reference frames, models and parameters.
This is the motivation for the establishment of the Integrated Global Geodetic Observing System (IGGOS).
With this Project, the scientific and infrastructural ba-

Short term focus for Geodesy

To integrate the three fundamental pillars of Geodesy geometry and kinematics, Earth orientation and rotation,and gravity field and dynamics- to achieve the maximum
benefit for the scientific community and society in general54

Geodetic Area
Geometry and kinematics

Earth’s rotation and orientation

Earth’s gravity field and dynamics

Table 6.1: Space techniques in geodesy
UseSpace Techniques/Space Missions
Geometrical reference systems,
VLBI (Very Long Baseline
global deformation processes,
Interferometry) * SLR (Satellite
temporal variations of the Earth’s
Laser Ranging) LLR (Lunar Lasersurface (solid, ice and ocean areas),
Ranging) * DORIS (Doppler
this includes plate tectonics,
Orbitography and Radiopositioning
earthquakes, volcanoes, natural
Integrated by Satellite) * GPS
hazards, climate change, etc.
(Global Positioning System) *GLONASS (Global Navigation
Satellite System) * GALILEO(Global Navigation System) * T/P(TOPEX/Poseidon - Ocean
Topography Experiment) * ERS-2(European Remote Sensing Satellite- 2) * GFO (GeoSat Follow-On) *JASON (First altimetric satellite
follow-on mission to
TOPEX/Poseidon) * ENVISAT(Environmental Satellite) * InSAR(Interferometric Synthetic Aperture
Radar) * ICESAT (Ice, Cloud, andland Elevation Satellite) *CRYOSAT (Altimetry mission todetermine variations in the thicknessof the Earth’s continental ice sheets
and marine ice cover)Polar motion and length of day
VLBI (Very Long Baselinevariation (oscillations of the Earth’s
Interferometry) * SLR (Satellite
rotation, caused by mass interchange Laser Ranging) * LLR (Lunar Laser
between atmosphere, ocean, ice
Ranging) * GPS (Global Positioning
sheets, and solid Earth)
System) * DORIS (Doppler
Orbitography and Radiopositioning
Integrated by Satellite)
Physical reference system, mass
CHAMP (Challenging Microsatellitebalance, quantification of mass
Payload for Geophysical Researchdisplacements (post glacial rebound,and Application) * GRACE (Gravity
ocean circulation, hydrology,
Recovery and Climate Experiment)
lithosphere)* GOCE (Global Ocean and Climate
Experiment) * Altimetry (T/P,
ERS-2, GFO, JASON, ENVISAT)

55

sis for all geodetic global change research shall be provided, viewing the Earth system as a whole by including
the solid Earth as well as the fluid components, the stationary and time-varying, geometry and gravity field.

atmosphere. It will provide its findings to interdisciplinary research, governmental agencies and the private
sector, inform and train the customers about the correctinterpretation and use of the geodetic products.

3. Combining consistently geometrical and physical references systems: The widespread use of the spacegeodetic techniques, in particular GPS, in the daily lifeof non-geodetic, ”normal” citizens requires an interface
between the developers (scientists) and the users, notonly to manage the technology contained in an instrument, but also to understand the scientific backgroundmaking the application of this technique useful and successful. The ”mm-level” precision, at times demandedby the users, is not yet disposable. Such requirements
can be achieved eventually by continuously improving
the reference system realisations (materialisation). Thistask includes, from the geometric point of view, thedensification and maintenance of the reference frame
through a large and globally homogeneous set of control points with coordinates of sub-centimetre accuracy,complemented by a velocity model at sub-millimetre per
year level. The velocity model should include both horizontal and vertical movements of the Earth’s crust, i. e.,a three-dimensional Earth’s deformation model is highly
required. On the other hand, from the physical point ofview, the natural reference surface for the heights, thegeoid, must reach the centimetre precision level, as well.
Then, a consistent relationship between the two systems
should be found to remove the incompatibilities of vertical positioning. More precisely, the following must be
achieved: the GPS-derived heights (h) refer to the ellipsoid (a geometrical model of the Earth), the commonlyused heights (H), that are consigned on maps or in geoinformation systems, refer to an equipotential surface of
the Earth’s gravity field (the geoid, a physical model ofthe Earth). The connection between these two types ofheights is known as geoid undulation (N); it describes
the distance between geoid and ellipsoid. The practicaluse of GPS demands that the equation h = H + N be satisfied in the 1 cm - level. This requirement includes otherimportant tasks, which must also be solved by geodesy.
Among them are: Definition of a global vertical reference system, and, since the geoid was classically defined
as a surface, which coincides with sea level, determination of the offsets between each local reference system,
based on a local sea level and the global one.

2. Promoting interdisciplinary actions to make the geoscientific information suitable to improve the life
standard on Earth: The Integrated Global Geodetic Observing System (IGGOS) should be part of theIntegrated Global Observing Strategy (IGOS), sponsored by the United Nations Educational, Scientificand Cultural Organisation (UNESCO) and the International Council for Science (ICSU). It should also be arecognized partner of the other, already existing, observing systems: Global Climate Observing System(GCOS), Global Ocean Observing System (GOOS) andGlobal Terrestrial Observing System (GTOS). In thisway, geodesy will participate more directly in providing fundamental information ”... to detect, locate, understand and warn of changes in the terrestrial ecosystems”.
3. Supplying a global observing system for hazard assessment: The observable signals of geodesy provide
the basis to identify regions with high risk in natural disasters. For instance, the repeated geodetic observationof crustal deformation zones allows us to locate possible
break points during earthquakes. The study of the gravity field variations in time leads to the detection of mass
movements, for instance, in volcanic areas, i. e., to theprediction of possible eruptions. Satellite altimetry allows scientists to forecast El Niño phenomena, the influence of which on the global climate (and also on agriculture, agronomy, hydrology) is very strong. The sea levelchanges, measured also with satellite altimetry, may be a
response of global warming (part of the steering effect).
In this way, geodesy observes the influence of the global
climate changes on the ices sheets, as well. All thesegeodetic activities form an accurate and reliable tool forclimate prediction (short-term and long-term) as well as
security warning in coastal zones. There are numerous
geodetic developments and applications supporting theformulation of policies to prevent and to mitigate natural disasters. In order to achieve the necessary reliability level, the combined work of all Earth sciences isrequired.
4. Providing a precise and reliable reference frame fornavigation, engineering, cadastre, geo-information:
The combination of the physical and geometrical reference systems, together with the improvement of theircomponents, support the users to reach 1 cm - level innavigation, to increase up to centimetre level the kinematic and real time positioning accuracy, and in general,
to build a consistent global spatial data infrastructure under the new concept of the digital Earth.

Short term benefits to Society
1. Providing better information to improve the knowledge about the system Earth: The Integrated Global
Geodetic Observing System (IGGOS) should be seen as
geodesy’s contribution to study the Earth system composed of solid geosphere, cryosphere, hydrosphere and56

5. Assisting international cooperation for developing
regions: The global concept of geodesy requires astandardisation of the procedures world-wide. In thiscontext, the technical transfer to developing countries
should be done at all levels: Densification of control points, homogenisation of the observing and analysis techniques, educational strategies, international
projects, joint meetings and reciprocal benefits in using geodetic information to sustainable development, including hazard mitigation.

4. Implementation of a reference infrastructure for
global 1-cm navigation: One of the most widespread
applications of GPS is the precise navigation in realtime. Because the propagation of microwaves throughthe atmosphere is not well known in real time, this kindof positioning is limited by atmospheric effects. In thespecific case of navigation, the corresponding deficiencies can be overcome by using complementary terrestrial
control navigation systems.
Strategies for achievement

In accomplishing the above-mentioned goals, the contribution of all geodetic disciplines is required. The field ofgeodesy is vast, but each of its areas, studying different phenomena and looking for the correlations to achieve the best
results, observe one and the same Earth. The convergence of
all these protagonists takes place under the auspicies of the International Association of Geodesy (IAG). In this framework,a general assessment of the current activities in the main
structure of IAG is provided in the following paragraphs.

1. Establishment and maintainance of the (fourdimensional) geometric reference frame. This task
is primarily solved by the geometry-related IAG services, namely IERS (International Earth Rotation Service), IGS (International GPS Service), IVS (International VLBI Service) and ILRS (International Laser
Ranging Service). The geometric reference frame is(must be) used for all high-accuracy applications (e. g.,
precise orbits for Low Earth Orbiting Satellites -LEOs-).

6.3 Assessment of current research inthe major geodetic disciplines
6.3.1

2. Improvement of the global reference frame. Design,development, and maintenance of a well- defined terrestrial IGGOS network, including all geodetic (and ancillary) techniques. The result might be called the IGGOS
network.

Reference Frames

Major scientific goals and challenges of the next decade

3. Atmospheric research using geodetic methods: Determination of global ionosphere models based on
microwave observations, high-resolution troposphericmodels and deploy standardised meteorological equipment on IGGOS network.

1. Determination of a reliable Earth reference frame:
As the positioning techniques may refer to different reference systems, the combination of their results may
generate inconsistencies that must be resolved throughthe definition and realisation of a common (integrated)reference system, i.e., a reference frame.

4. Participating in the definition and implementationof new Global Navigation Satellite Systems (GNSS).
It is IAG’s declared goal to include upcoming alternative navigation systems (like GLONASS, GALILEO, ...)
into its scientific work. New systems should have at least
the same accuracy level as GPS.

2. Homogenisation of the geodetic control world-wide:
The geodetic control has to be realised by a set of points(pillars or instruments) with highly accurate coordinates.
Because the space-geodetic techniques (except GPS) arevery expensive, the control points are, at present, localised mainly in Europe, North America, Japan andAustralia, with a clear unbalance towards the northernhemisphere. To improve the observing system and its
results, it is necessary to achieve a more homogeneus
global distribution.

6.3.2

Gravity Field

Major scientific goals and challenges of the next decade
1. Implementation of a precise Earth gravity model:
Global gravity field modelling is required for large-scale
problems, including the determination of dynamic satellite orbits, inertial navigation and development of geophysical and geodynamic models. This is achieved byhigh-degree gravity field models, which may then used
to establish a global vertical datum and for the transformation of geometric GPS-heights to physical (normal or
orthometric) heights.

3. Velocity field models and time dependence of the coordinates: The position of a geodetic site is describedby three cartesian coordinates [X, Y, Z] and the corresponding change in time, i. e., its velocities [V x , Vy , Vz ].
Because the Earth is not rigid and because it is impossible to measure these displacements ”everywhere,” a representative model must be derived for the velocity feld.
57

2. Improvement of the knowledge of the Earth’s gravity field and its temporal variation: Conventionally,
the gravity field has been treated as a static field because
it is dominated by the internal mass distribution of thesolid Earth, which was created on time scales from millions to billions of years. With the new satellite gravity
missions, complemented by airborne gravity, is possible to observe variations caused by dynamic processes(mass redistribution) that vary on time scales from hours
to thousands years.

and thermal expansion on sea level variations, including
secular changes.
Strategies for achievement
1. Implementation of a collocated reference frame withhighly precise gravity instruments (absolut and relative
gravimeters), selected tide gauges, and a zero-order levelling network. This task must be tackled by IGGOS.
2. Maintenance and improvement of a unified worldwide gravity network for monitoring gravity field time
variations and providing a net of ground control points
for spatial gravity surveying.

3. Combination of terrestrial and spatial gravity field
information: This task has been studied intensively, but
a complete, convincing and feasible methodology is still
missing.

3. Establishment and maintenance of the ”official sea
surface” based on the results of all available altimeter
missions. Task for the altimetry service (to be created).

4. Developing an optimal strategy for the assimilation ofgeodetic gravity information into global inverse geodynamical models: This aspect has been traditionallytreated in geodesy, starting from the old isostatic theoryof the middle of the nineteenth century, and has proved
to be important to assess modern rheological theories.

4. Establishment and maintenance of the official global
model of ”Earth’s gravity field and geoid,” which isconsistent with all available geometric information (including sea surface) and based on results from analysesof classical geodetic satellites (Lageos, etc.), dedicatedgravity missions (CHAMP, GRACE, GOCE, etc.), andoceanographic information. This is a key activity to becoordinated by IGGOS.

5. Definition and establishment of a unique global vertical reference System, including the determinationof a highly precise geoid (on 1- cm level): The classical height datums are defined independently by meansea level observations at different tide gauges over different time intervals. In this way, the combination ofheights referred to different tide gauges is not reliable;
discrepancies up to meter level can be expected. It isnecessary to define a unique global reference level independent of spatial and temporal sea level variations.
On the other hand, the comparison of GPS-derived geoid
undulations (N = h - H) with gravimetric geoid models
presents still discrepancies in the decimetre-level. It isnecessary to improve the knowledge of the gravity field(gravity field satellite missions), of the solid Earth surface (spaceborne InSAR measurements), of the oceanic
surface (radar altimetry), and to complete surveying oflarge uncovered areas, like Antarctica.

5. Improvement of gravity data with high spatial resolution: Densification of terrestrial, marine, airborne,
gravimetry and satellite gravity field observations (satellite altimetry, dedicated gravity satellite missions, etc).
6. Modelling of vertical velocities, sea level variations
and an adequate combination of terrestrial levelling
techniques and the global positioning system.
7. Implementation of a unified global height system: asa result of these six items. They should be coordinatedby IGGOS.

6.3.3

Earth Rotation and Geodynamics

Major scientific goals and challenges of the next decade

6. Precise orbit determination, including the temporalvariation of the gravity field: This task is in essence
solved for the static part of the gravity field and for the”normal” tidal variation. For temporal variations, as they
will be revealed by the new space missions CHAMP,GRAVCE, GOCE, a new methodology must be developed.

1. Modelling of mass displacements within the system
Earth from geodetic observations: Earth rotation isgoverned by the three body problem Earth-Moon-Sun.
The Earth has to be treated as a body of finite extensions
consisting of the solid Earth (which has non-rigid properties), the oceans, and the atmosphere. Geodynamic
processes play an essential role. This includes the lunar
and solar gravitation and mass redistribution in the atmosphere, the hydrosphere, the solid Earth and the liquidcore. The variations are secular, periodic or quasiperiodic and irregular in nature. By observing these variations, it is possible to reconstruct (to some extend) the
mass (re)distribution on the system Earth.

7. Identifying the relationship between the sea levelchange observed by satellite altimetry and global
warming: The accuracy of the sea level determination
by satellite altimetry is presently approaching 10 mm.
The combination of satellite altimetry and time varying
gravity leads to identify the influence of mass changes
58

2. A three-dimensional Earth deformation model: Thechanges in time of the coordinates on the Earth’s surface are determined by repeatedly measured positions of
the same points with the help of geophysical models ofplate tectonics. However, the geophysical models are
based on seismological and magnetic data observed inplate boundaries, showing only constant (linear) superficial (two-dimension) displacements and neglecting theinter- plate and intra-plate deformation. It is necessary to
implement a global, precise, detailed, physically realistic reference model for crustal movements to include andreplace the geophysical models. It should also describe
the horizontal and vertical components of the deformation.

6. Integration of tide gauge data with satellite altimetry
as well as oceanographic and meteorological data (seasurface temperature, salinity, current velocities, air pressure).

6.3.4

Positioning and Applications

Major scientific goals and challenges of the next decade
1. Applications of geodetic positioning using threedimensional geodetic networks (passive and active
networks), including monitoring of deformations:
Geodetic networks consist of monumented (passive)
sites or of continuously observating (active) stations.
They provide the reference frame for positioning at all
scales. Global networks give the global realisation of
the reference systems, which form the fundamental basis for all national or continental geodetic surveys. They
are the basis for geo-information systems and map series. Local networks are established for engineering andexploration projects and for geodynamic investigations.

3. Improvement of the knowledge about the remaining
Earth’s rotation variations: There are still variationsin the Earth’s rotation rate, which are not totally understood (e. g., the driving mechanisms of the Chandler
wobble and all decadal variations, to mention only two
examples).
4. Sea surface topography and sea level change: Variations of the sea level with time are relevant in geodesy
for the definition and realisation of height reference systems, especially the geoid. On the other hand, the determination and interpretation of sea level changes lead toa better understanding of the ocean-atmosphere interactions and their influence on climate. An acceleration of
the global sea level rise would indicate climate changes
related to the global warming.

2. Applications of geodesy to engineering: Positioning
based on an adequate reference frame is a basic step inevery engineering project. Geodesy plays an importantrole in the planning and implementation of engineering
projects. The high precision of the geodetic methods
also allows it to monitor and predict deformation andmovements in engineering constructions, i. e., mines,
bridges, dams, areas of geological hazard, etc.
3. Atmospheric investigations using space geodetic
techniques: GPS radio occultation measurements area promising tool for remote sensing of Earth’s atmosphere. This technique, implemented in new satellite
missions (e. g., CHAMP), offers a wide spectrum of
applications in climate monitoring, weather forecast andatmospheric research.

Strategies for achievement
1. Observation, analysis and data interpretation in tectonic regions, post-glacial rebound and sea-level fluctuations, including the proper modelling of them and theirrelationship with environmental changes.
2. Examination of the influence of the Earth’s mobile
constituents (fluids) on the Earth’s orientation and position in space, defined broadly in terms of length ofday, polar motion, nutations, geocenter and gravity variations.

4. Modelling the path delay of electromagnetic waves
in the atmosphere: In practically all geodetic measurements, electromagnetic waves serve as signal carriers, this includes the methods of satellite and terrestrial
geodesy as well as geodetic astronomy. When travellingthrough the atmosphere, the waves experience changes
in velocity and in the curvature of the path.

3. Computation of time variations of angular momenta
and related torques, gravitational coefficients, and geocenter shift for all geophysical fluids based on global
observational data, and/or products from state-of-the-art
models.

5. Increased accuracy of real time and absolutesatellite- based positioning, including the integrationof new systems for navigation and guidance of platforms: GPS plays a dominant role in many navigation
systems used today. It is beginning to play an increasingly important role in providing accurate time signals
for many industries. Applications are comprised of land
surveying, autonomous vehicle control, including concepts like the smart highway system, marine navigation,

4. Establish ice mass balance and monitor the solid
Earth as a continuum using space techniques such as
InSAR, CRYOSAT, ICESAT.
5. Improve and maintain geophysical models relevantfor geodesy.
59

air traffic control, satellite navigation, and power signal
time synchronisation. By exploiting differential signals,
GPS is capable of positioning with an accuracy in theorder of a few millimetres.

applications essentially require merely low level accuracy. Standards ”specify the absolute or relative accuracy of a survey,” and they should be derived from theobjectives of the geodetic networks in terms of meeting
actual needs. In this way, the users of geodetic information are in a position to plan new projects, thus reducing
the actual costs and the time requirements.

6. High-resolution global and regional Digital Elevation Models (DEM): A DEM is a digital file consisting of terrain elevations for ground positions at regularly
spaced horizontal grids. They are useful to model terrain
and gravity data in geoid determination, surface deformation, searching energy resources, calculating the volume of proposed reservoirs, determining landslide probability, etc.

5. Strong cooperation to related surveying/navigation
organisations, such as International Federation of Surveyors (FIG), International Society of Photogrammetry
and Remote Sensing (ISPRS), Institute of Navigation(ION), UNAVCO, etc., is required to achieve this goal.

7. The role of geodesy in the ”Digital Earth” project:
Digital Earth is defined as ”a virtual representation of
our planet allowing it to explore and interact with thevast amounts of natural and cultural information gathered about the Earth.” Digital Earth Models allow it toscientists, teachers, policy-makers, etc., to develop detailed analyses of features and phenomena as small as
one meter in size. The consistent combination of all of
this information is only possible if the reference frame
is provided by geodesy.

6. Participation in the implementation of initiatives related with ”referencing geo-information,” such as
Digital Earth, Global Map, Global Spatial Data Infrastructure (GSDI), etc.

6.3.5

TheoryThe continuous increase in number and accuracy of geodetic
measurements compels the models to become more and morecomprehensive in order to account for new effects, which
are becoming accessible to the new measurement techniques.
When a new model is developed, it may become desirable toimprove the measurement procedures again testing the predictions by the theory with the reality, and the cycle begins
again. This process is only possible if the theory is constantly
developed in geodesy. The theory is the common basis for all
geodetic areas; it is ”understanding systematically the particular area of the real world, which is object of the investigation.” In this way, theory does not recognise specific boundaries, and its development cannot be ”planned,” but it advances according to the scientific requirements. In this case,its concrete task is related to developing fundamental mathematical and physical concepts and methodologies requiredby geodesy. It includes the articulation of the challenges ofgeodesy, in terms of mathematics and physics, and common
activities with scientists in other areas of science and engineering.

Strategies for achievement
1. Elimination or reduction of the atmospheric refraction on geodetic measurements by improving the instrument design, observation methodology, and by theuse of atmospheric models based on data collected on
the Earth’s surface and in space.
2. Implementation of algorithms for accurately and reliably processing the GPS signals for timing and navigation leads to solving problems with reflected signals(multipath), integer solutions of positioning algorithms,
to determine phase ambiguities in position determination and to estimate the water content in the troposphereand the electron content in the ionosphere
3. Improvement of the currently avaliable Digital Elevation Models (DEM), based on digitised topographic
and bathymetric information from the new space techniques. Satellite radar altimetry serves for the height determination of the Greenland and Antarctica ice sheets
and provides bathymetric information, due to the correlation between the ocean surface and the ocean bottom. Space and airborne interferometric synthetic aperture radar (InSAR) has become an efficient method forthe development of high resolution DEM’s.

6.4 Recommendations
The scientific goals in geodesy and possible strategies forachievement in the next decade have been presented. There
are some logistic aspects, which could contribute to the improvement of the dialog between geodesy, other Earth sciences and society in general. Therefore, some organisational
recommendations can be presented below. They may be useful not only for the International Association of Geodesy(IAG), but also for the International Union of Geodesy andGeophysics (IUGG).

4. Definition and maintenance of geodetic standards:
The geodetic networks serve as a three-dimensional reference for an increasing number of applications; these60

1. Develop and define a consistent model for the System
Earth: IUGG should promote and coordinate the implementation of a global observing system and modelling,that includes all the disciplines of its Associations looking at the results in an integrated manner.

8. Interdisciplinary work: IUGG should promote moreinterdisciplinary schools and research units at the international level, to improve mutual understanding and cooperation between its Associations.

6.5 Opportunities
forplinary research

2. Prediction and mitigation of natural disasters: IUGG
and its Associations should be instrumented to understand natural disasters and support the formulation of
prevention and mitigation policies. In this way, an integrated vision of risk assessment supporting the actionof international and interdisciplinary services in terms ofrecognition by international institutions (UN, UNESCO,etc.) and national institutions (governments, agenciesetc.) is required.

interdisci-

Classically, mapping was viewed as the main purpose ofgeodesy; it should make control surveying to provide position control for mapping. However, by establishing reference
geodetic networks, geodesy became the fundamental sciencefor disciplines related to positioning, such as urban and environmental management, engineering projects, (internationaland national) boundary demarcation, ecology, geography, hydrography, etc. Still other applications are found in scientificfields that have a two-way relationship with geodesy: whilegeodesy supplies one kind of information to them, they provide another kind of information for use in geodesy, for example: theoretical and exploration geophysics, geodynamics,
space science, astronomy, oceanography, atmospheric science, geology, etc. The new techniques to observe and toanalyse the Earth as one unique system make the relationshipbetween these disciplines stronger; it is almost impossible toidentify clear boundaries between their study fields. Based onthese considerations and keeping in mind that IAG is one of
the seven Associations of IUGG, we mention a few projects,
which may be of common interest to many (not to say all)IUGG associations:

3. Promotion of the geosciences products: IUGG and its
Associations should increase the advertising concerning
the applicability of their products. They should, e. g.,
explain and outline the importance of the achievements
for society.
4. Interaction with other Earth societies : IUGG and its
Associations should strive for a closer collaboration withother scientific organisations like the American Geophysical Union (AGU), European Geophysical Society(EGS), etc.
5. Attracting young people: IUGG and its Associations
should publicize new results with the goal to attract
young and bright people from mathematics, physics, astronomy etc., to its disciplines, e.g., by establishing international prizes, by fostering the creation of international doctorates in geosciences, by supporting the creation of international institutes, etc. Free and cheap publication facilities (Internet sites, journals, etc.) are also
desirable.

1. Analysis and prediction of sea level variations, including ocean modelling: IAG, IAMAS, IAPSO,
IAHS, and IASPEI. Geodesy provides precise information concerning the melting of glaciers and polar icecaps, sea level change, atmospheric mass movements,
ground water and soil moisture.

6. Geosciences world-wide:IUGG and its Associations
should encourage a stronger participation of geoscientists from developing countries. This can beachieved by assuring that they are able to participate inscientific collaborations (not necessarily only in meetings), like projects and programs, by making data available to them and by encouraging all nations to became
members of IUGG. Another action would be to offer freemembership to individual scientists.

2. Precise modelling of crustal deformation, including
plate tectonics, volcanoes and earthquakes: IAG,
IAVCEI, and IASPEI. Geodesy precisely monitors
crustal deformation (secular and episodic, extended andlocal), as well as gravity and Earth’s rotation changes
due to mass displacements.
3. Precise modelling of the atmosphere (ionosphere andtroposphere): IAG, IAGA, and IAMAS. Geodesy provides information concerning TEC (Total Electron Content), pressure and humidity from atmospheric sounding using GPS. It might also contribute information on
short-term variations.

7. Geoinformation world-wide: IUGG should improve
the work in terms of services in its Associations and integrate them into a unique system, which is justified ona scientific ground by the IUGG structure. It should include a global policy of free and open data exchange
in all fields of Earth sciences (sea level, meteorological
data, geodetic data, etc).

4. Inverse modelling of the continental lithosphere andupper mantle: IAG, IAGA, IAVCEI, and IASPEI.
Geodesy can model spatial and temporal variations of61

the Earth’s gravity field due to internal mass imbalancesand quantify horizontal and vertical crustal movements.

and attainments share the same objective with the other geosciences: ”to improve the life standards of mankind.” Fromthe sole geodetic point of view, in spite of the presented future perspective, these activities are just the improved continuation of an interminable process that began more than 2600
years ago with the first questions about the actual figure of the
Earth. Now, our responsibility is keeping this process moving
to inherit our best efforts to the coming generations.

5. Observing and understanding the global climatechanges: IAG, IAMAS, IAPSO, IAGA, IAVCEI, IAHS,
and IASPEI. Geodesy provides precise information
about variation (spatial, secular and temporal) of the sea
level and Earth’s rotation rate changes due to geophysical processes, including mass redistribution effects inthe atmosphere, hydrosphere, and solid Earth.

Bibliography

6. Implementation of a global Earth management system: IAG, IAMAS, IAPSO, IAGA, IAVCEI, IAHS, andIASPEI, coordinated by IUGG. It should include observation, analysis, modelling and an adequate digital
representation of the Earth’s dynamics as a function of
space and time. This item could be seen as a combination of the four previous topics.

Beutler, G. On behalf of the IAG Committee for therealisation of the new IAG structure. September 2002.
http://www.gfy.ku.dk/ iag/newstructure/new iag s 02.htm
Beutler, G. Drewes, H. Reigber, Ch., Rummel, R. (2003):
Proposal to establish the Integrated Global Geodetic Observing System (IGGOS). IGGOS Planning Group.

7. Hazard prediction and mitigation: IAG, IAMAS,IAPSO, IAGA, IAVCEI, IAHS, and IASPEI, coordinated by IUGG. As a continuation (or direct application)of the previous item, it should lead to develop global, regional, national and local prediction systems to prevent
natural disasters (such as landslides, inundation, volcano
eruptions, earthquakes, hurricanes, cyclones, etc).

Dickey, J. (2001): Interdisciplinary space geodesy: Challenges in the new millennium. In: Vistas for Geodesy
in the New Millennium. IAG Symposia, Vol. 125. pp.
590-594, Springer Verlag, Berlin, Heidelberg.
Helmert, F. R. (1880): Die mathematischen und physikalischen Theorien der Hoeheren Geodaesie. Teubner,
Leipzig (reprint Minerva GmbH, Frankfurt a. M. 1961).

These aspects do not exclude other common activities
which are being developed with organisations other thanIUGG, such as International Astronomical Union (IAU), International Union of Geological Sciences (IUGS), American
Geophysical Union (AGU), European Geosciences Union(EGU), and some global programs of the International Council for Science (ICSU), for instance: Scientific Committee on Antarctic Research (SCAR), Program on Capacity
Building in Science (PCBS), Committee in Data for Science and Technology (CODATA), Scientific Committee on
Problems on the Environment (SCOPE), Scientific Committee for the International Geosphere-Biosphere Program (SCIGBP), Special Committee for the International Decade for
Natural Disaster Reduction (SC-IDNDR), Special Committee on Oceanic Research (SCOR), Science Committee on
Solar-Terrestrial Physics (SCOSTEP), Committee on Space
Research (COSPAR), Committee on Frequency Allocations
for Radio Astronomy and Space Sciences (IUCAF), Scientific Committee on the Lithosphere (SCL), etc.

Rummel, R. (2001): Space geodesy and Earth sciences. In:
Vistas for Geodesy in the New Millennium. IAG Symposia, Vol. 125, pp. 584-589, Springer Verlag, Berlin,
Heidelberg.
Rummel, R., Drewes, H., Beutler, G. (2001): Integrated
Global Geodetic Observing system, (IGGOS): a candidate IAG project. In: Vistas for Geodesy in the New
Millennium. IAG Symposia, Vol. 125, pp. 609-614,
Springer Verlag, Berlin, Heidelberg.
Sanso, F. (2001): The greeing of geodetic theory. In: Vistas for Geodesy in the New Millennium. IAG Symposia,
Vol. 125, pp. 595-601, Springer Verlag, Berlin, Heidelberg.
Senatskommission fuer Geowissenchaftliche Gemeinschaftsforschung der Deutschen Froschungsgemeinschaft (1999). Geotechnologien: Das ”System Erde”:
Vom Prozessverstaendnis zum Erdmanagment. GFZ,
Potsdam.

6.6 Conclusions

Torge, W. (2001): Geodesy. 3rd Edition. De Gruyter, Berlin,
New York.

The presented reflections show a global assessment of the current and coming activities in geodesy. They should not beseen as isolated tasks; on the contrary, they are active components of the required analysis to better understand our planet.
Geodesy is one of the oldest Earth sciences. Its challenges

Vanicek P., Krakiwski E. (1986): Geodesy: The concepts.
North Holland, Amsterdam.

62

Chapter 7

International Association of Meteorological andAtmospheric Sciences
S. Adlen

7.1 Introduction

ward a vision of the future.
Views presented within this report are those of the author
alone and are intended only as the basis for discussion. The
author would, however, like to thank all those who aided
in the development of this document, particularly Dr. D. J.
Frame, Professor F. W. Taylor, Dr. W. A. Norton and Dr. J-N
Thepaut.

The Meteorological and Atmospheric sciences seek to understand physical processes in the atmosphere, including radiation, the physics of clouds, atmospheric electricity, boundary layer processes and atmospheric dynamics and chemistry.
Despite the huge complexity of the problem, the atmosphericsciences have developed an impressive capability over the
past century to help society anticipate atmospheric events.
Progress is accelerating today as improved observational andremote sensing capabilities provide more accurate resolutionof atmospheric processes, and enhanced physical understanding, new modeling strategies, and powerful computers combine with these measurements to result in continually improving atmospheric simulations and predictions.
The rate of progress in such a diverse field as the atmospheric and meteorological sciences is, however, dependent
upon several factors. Co-operation, collaboration and dissemination of data across the full breadth of the field are essential,
along with a flexible road map to provide focus and direction
for research. The IUGG general assembly provides the perfect platform for reflection upon the current status of research
and a re-assessment of the direction in which research in theatmospheric sciences should be progressing.
Many reports (e.g., IPCC [2001]) have been produced,
assessing research in the atmospheric and climate sciences.
This document differs by giving a young scientist’s perspective on future research. Aims for the future in the atmosphericsciences are presented over long term timescales (> 50 years)
along with more immediate research priorities to be pursued
over the next decade.
The report emphasizes atmospheric research, but also
touches upon the societal benefits of atmospheric science.
Goals for the future are presented, the current direction ofresearch in the atmospheric sciences summarised and several
recommendations are suggested with the aim of moving to-

7.2 Long Term Goals
The relevance of science is often best measured by its value
to the end user. In the case of atmospheric science, the entire
population that breathes the atmosphere and experiences thevariability of the Earth’s weather systems could be considered an end user. If one accepts both that the human race isworth preserving and that prior knowledge of events improves“quality of life,” then the value of atmospheric research is unquestionable. It is in the privileged position of being bothcritical to our future survival and a central feature in other“comfort factors” associated with everyday life.
To date, atmospheric research has already provided a number of ways of improving both the quality and sustainability of life. In assessing the causes of and probable future
trends in climate change and in the forecasting of high impact weather, the probability of our survival is constantly being improved . At the current time, there is also a growing
market in which atmospheric science benefits more specificend users, e.g., through energy, health and agriculture. It isthrough these benefits to society that atmospheric researchfinds its “raison de etre” beyond that of an extremely complex intellectual challenge.
The ultimate scientific aim of atmospheric research must
be an atmospheric (and coupled Earth system) model with an
infinite temporal and spatial resolution and certainty in prediction. This ultimate goal is obviously eventually limited63

by the underlying principles of both Quantum Mechanics andChaos. Thankfully, current limitations in a progression toward this ultimate limit are found in difficult, but surmountable, problems, such as computing power, observational resolution and modeling inefficiencies. These limitations result in
the fact that an effectively continuous problem in space andtime must be represented on an unnecessarily coarse grid withan incomplete description of the physical processes describing the situation.
Techniques developed in the field have already made enormous progress in characterising and reducing errors inherent
in the process of modeling the atmosphere and its evolution.
However, whilst knowledge of the atmosphere and climate
has improved dramatically over recent years, we are still notin the position to predict with sufficient certainty what the
future holds or to exert any controlled influence over how
things might change. This applies with regard to both longterm (decadal to millennial) climate prediction and short term(hourly to seasonal) weather forecasting.
Climate change is arguably the greatest challenge facing
mankind in the coming decades. The primary goal of atmospheric research must hence be to get to the point where wecan convince all policy makers that mechanisms of climatechange are adequately understood in order that detrimental
anthropogenic effects on our climate can be nulled before theonset of an irrevocable dynamic. Progress in atmospheric research is, however, accelerating rapidly and goals for the next
50 years should stretch both our intellectual and engineering
capabilities. A realistic but suitably challenging goal for the
next 50 years is:changes in climate or null the onset of any high impact
weather events.
• Location and Development of other Habitable Environments
There is a strong possibility that anthropogenic influences upon our planet are spiraling out of control. Consideration should be put toward finding and developing
other potential habitats in which the human race mightsurvive. These habitats might include additional planetary systems
The benefits of pursuing the goals and projects outlinedin this section are beyond doubt. However, all of the above
long term undertakings require research over more immediate timescales in order to be able to progress and will represent the culmination of both atmospheric research and research in other related disciplines. Improvements in observations, computing and modeling will all be required in orderto achieve these goals. Some more immediate priorities are
outlined in the following section.

7.3 Short Term Priorities
On intermediate timescales, the atmospheric sciences must be
looking to improve upon the current understanding of atmospheric processes in order to be in a position to implement andsatisfactorily conclude the projects of section 7.2 if required.
Recent advances in computing power are allowing unprecedented opportunities as regards atmospheric modeling. The
efficient exploitation of these opportunities should be the immediate short term aim of the atmospheric community.
We are still in the position where our knowledge of the processes taking place in the atmosphere is far from complete.
Progress required in each atmospheric discipline is in many
ways limited by progress in each of the other fields. Each field
is ultimately a constituent part of a single system and hence
co-operation is required. Some of the most critical issues relevant to the bureau of IAMAS, regarding the enhancementof our knowledge that need to be addressed over the coming
decade are outlined below.

“To develop and integrate models of all processes (at all
scales) occurring both in the atmosphere and at its
boundaries, resulting in the capacity to predict events (onscales from hours to millennia) with sufficient accuracy so as
to be able to understand their occurrence and minimise theireffect where possible.”
As previously stated, from the perspective of selfpreservation, the most important role of the atmospheric sciences is the part they play in the perpetuation of the human race and in the environment in which we reside. Our
improved knowledge of atmospheric processes and climatechange should then be used in any possible way to enhance
the probability of the continuation of the human race. The following two long term projects, utilising enhanced knowledge
in the atmospheric sciences could reasonably be pursued.

7.3.1

Atmospheric Chemistry

Underlying processes in the atmosphere are the chemical reactions taking place. The ability to measure and parameterise
these microphysical processes is central to atmospheric science.

• Forcing of the Atmosphere to Maintain a Habitable Environment
If and when atmospheric processes, climate and climatechange are understood sufficiently, it might be possible
to intentionally influence the climate in order to sustain
the Earth, improve our economies, mitigate any adverse

CloudsClouds are important in the atmosphere because they strongly
modulate incoming solar and outgoing thermal radiation.
64

Ozone and Greenhouse Gases

They are also the source of precipitation, and a key element in the hydrologic cycle. They are currently under intense scrutiny by researchers to gain a better understandingof their role in our environment Liou [1986]. This knowledge
is needed for better predictions of both climate change, andforecasting.
Radiative properties of clouds depend upon their microphysical properties such as water-ice content, size spectra andshape. These same properties determine the precipitation rate
Dowling and Radke [1990]. Understanding the role of theseproperties in geophysical processes and correctly parameterising the processes in models are essential. Cloud microphysics is a growing area of research, but currently limiting
progress in other areas of atmospheric science (section 7.3.2).
Forecasting and climate models both require improved parameterisations of clouds as the effect of spatial and temporal
resolution on all processes and couplings in the atmosphere
are investigated.
A number of investigations are under-way into different
cloud types, including polar stratospheric clouds, notilucent
clouds and cirrus clouds.
The ability to remotely sense cloud microphysical properties from satellites is also crucial if the cloud data is to be input into real time forecasting models with the global coveragethat is required. Much research is occurring in the retrievalof cloud microphysical properties from remotely sensed data,e.g., Baran et al. [2001]. In addition, several missions, suchas Cloudsat and ICESat, are in progress to measure cloudproperties from remotely sensed data. With a combinationof experimental and modeling initiatives, real progress will
be made in what is undoubtedly one of the most complicatedproblems in atmospheric science.

Atmospheric abundances of most greenhouse gases are attheir highest values since measurements began. Much publicised research over the past few years has demonstrated thatozone changes since the pre-industrial period are coupled toclimate change. It is now the third most important greenhousegas behind CO2 and CH4 Ehhalt et al. [2001]. The magnitude of its effect, however, is critically dependent upon the altitudes at which depletion occurs and must be thoroughly understood in order to unravel the detection of climate change
from natural variability. It is understood that changes in all
greenhouse gas abundances and lifetimes will have the effectof altering climate forcings, but uncertainties remain high.
These uncertainties are improving, due largely to collaboration in various observation and modeling campaigns. Better
simulation of the past two decades, and of the current decade,will improve confidence in projections of greenhouse gases.
Global observations from satellites, radiosondes, and surface
data all remain essential in monitoring and understanding thechemistry, transport and feedbacks of ozone and other greenhouse gases. Currently, one of the most important problems
that needs addressing is the modeling of sub grid scale processes in chemical transport models. The chemistry in theatmosphere is generally highly non-linear, and thus highly dependent upon resolution. Surface emissions are often highly
localised so model resolution becomes critical. Improving the
spatial scale in chemical transport models is hence essential.
Techniques, which allow an increase in resolution locally via
a two-way nesting approach, promise to provide the bridge
between features from local to global scales.
The Carbon Cycle
Atmospheric chemistry is of substantial import in the understanding of the carbon cycle in terms of its reactions both in
the atmosphere and at atmospheric boundaries Prentice andet al. [2001]. Carbon plays many roles in the Earth system.
It forms our food and acts as our primary energy source but
is also a major contributor to the planetary greenhouse effectand the potential for climate change (section 7.3.2). Carbon
dioxide and methane concentrations have been increasing in
the atmosphere, predominantly due to our use of fossil fuels and land clearing. Of the carbon dioxide emitted into theatmosphere, about half is currently taken up as part of thenatural cycling of carbon into the ocean, and into land plants
and soils. Successful carbon management strategies need to
be based on solid scientific information of the basic processes
affecting the global carbon cycle.
Models that include ecosystem distribution and condition,
biological processes determining exchanges with the atmosphere from the land and the ocean, and the transport of carbon within the Earth system are required. These models will
rely upon the integration of geographic information, remotesensing data and comprehensive databases.

Aerosols
Aerosol particles are also important in the atmosphere, directly by absorbing, emitting and scattering light and indirectly by serving as cloud condensation nuclei and impacting
precipitation rates. They are considered a much greater uncertainty in climate forcing than CO2 concentrations as they
have a much greater spatial and temporal variability making
their quantification more difficult. Their forcings are regionally variable and their couplings to climatic effects requiresignificantly more research Penner and et al. [2001].
It is vital that aerosol distribution databases are both spatially and temporally resolved along with their sources andsinks. Further laboratory based study into the conversion
mechanisms that transform precursors into aerosols, combined with 3-D global observations are required.
Existing systems, such as AVHRR, TOMS, GOES andMETEOSAT, have been used to aid in improving the chemical meteorology need to aid aerosol estimates. New
aerosol data products are also being obtained from SeaWiFS,
MODIS, MISR and CERES instruments NASA [1999].
65

The Global Water Cycle

is essential to our continued well-being. Directly coupled toclimate are factors central to sustaining life on the planet,such as water resources, food and temperature. For a fuller
discussion on climate and climate change see IPCC [2001].

Water plays integral roles in both surface conditions and theatmospheric circulation. The conversion of liquid and solid
water to water vapour results in a local latent cooling. Water molecules also have a large impact on Earth’s radiationbudget. They are strong absorbers of infrared radiation, andthe resulting greenhouse effect of atmospheric water vapour
is, by far, the strongest determinant of the Earth’s surface climate. Measuring and forecasting spatial and temporal patterns in water vapour and clouds are hence essential to addressing climate, water resources, and ecosystem problems.
Aside from the previously mentioned problem of modelingcloud processes, two further areas of the hydrologic cycle that
require improvement are in the subgrid scale modeling of soil
moisture and evaporation and the coupling of these models to
GCMs.
The global water cycle interacts with all components ofthe Earth system. A hierarchy of simulation models are required, including GCMs, mesoscale models, basin scale hydrologic models along with validation against global observation data such as EOS. Techniques utilising the recent advances in computing power will allow for rapid progression
in the modeling of the hydrological cycle.

Development and Integration of High Resolution Coupled
Climate Models
Numerical models of the Earth system must be based upon an
accurate representation of physical, chemical and biologicalprocesses. All processes and interactions, which occur on awide range of spatial and temporal scales and, in many cases,
are highly non-linear, need to be included.
Modeling the climate system will require two basic strandsof development: improvements in model resolution and improved model parameterisations. The first of these allows us
to more realistically model finer scale phenomena, with thesecond allowing us to better deal with those scales we cannot
model explicitly.
It has long been known that small scale features can manifest an influence upon large scale processes in the atmosphereon finite timescales. This has probably been most memorablystated by Lorenz, “...one flap of a seagull’s wing may forever change the course of the weather.” It is imperative todevelop models that can explicitly simulate flows on smallerscales, enabling the capture of significant non-linear interactions between different space and time scales and different
components of the Earth system. Whilst there will always be
unresolved scales of motion, giving rise to a finite forecasthorizon, at the present time, an increase in resolution would
greatly improve the value of predictions.
Most current climate models have a typical resolution of∼ 3◦ in the atmosphere and ∼ 1◦ in the ocean. This does notallow for adequate representation of the climate system in either component. An eddy permitting ocean model has beenshown to provide a better representation of western boundary
currents and a more accurate simulation of equatorial waves(which are a key element of El Nino). Higher resolution simulations of the atmosphere have also already demonstrated improvements in regions where orographic effects are important
Pope and Stratton [2002]. Both chemical and land surface effects are again highly dependent upon resolution and would
benefit from resolving finer scales (sections 7.3.1 and 7.3.2).
Higher resolutions of <∼ 1/3◦ ocean and <∼ 1◦ atmosphere
will allow the exploration of the processes in climate systemthat give rise to its variability on all scales.
Even with increases in resolution, climate modellers still
also face the on-going need to improve parameterisationsof sub-grid scale phenomena. Effects from arbitrarily small
scales will still affect behavior at larger scales Lorenz [1969],
and the climate modeling community needs to address betterways of dealing with the residual incompleteness of models.
Cloud microphysics, for example, will need to be parameterised regardless of any foreseeable improvements in resolu-

Summary
The parameterisation and modeling of cloud microphysics
and the high resolution modeling of chemical transports are
currently both vital areas of research . With recent advancesin computing power, both climate and forecasting models areexperimenting with optimal methods for faithfully representing cloud processes and chemical transports. The research
objective of attaining sufficiently accurate parameterisations
can only be achieved through a synergism of transport models and GCMs validated against comprehensive spatially resolved databases. The implementation of global observing
systems measuring horizontally and vertically resolved critical cloud and chemical parameters will be required as input
to both the models and the databases. These measurements
should involve a combination of remote sensing, in-situ, aircraft and radio sonde data. Research will certainly be helped
by observations on improved spatial scales, such as HIRDLS(Gille et al. [1994]). In conjunction, a systematic effort isrequired to improve the documentation of time resolved atmospheric composition over regional and global scales. Thisis a book keeping exercise but imperative for the monitoringof pollution and climate change.

7.3.2

Climate and Climate Change

The aim of understanding the physical and chemical basis ofclimate and climate change in order to predict climate variability from timescales of seasons to centuries and beyond
and to assess the role of human activities in affecting climate
66

tion.
Within any general circulation model (GCM) there aremany parameters which are poorly constrained by observations. Many of these have been found to be sensitive tosmall perturbations. Parameter perturbations can add nonlinearly, and in order to better understand the physics of themodels we need to disentangle the physical mechanisms behind model response. We need to identify those processes
which have little impact on the mean climate but a large effect on climate sensitivity, and secondly identify those parameterisations which are both influential and poorly constrained.
The first of these undertakings will help us gain an improved
understanding of climate sensitivity and second will address
systematic model errors. As we develop more convincing andhigher resolution component models, our reliance on parameterisations will broaden and there will be a continual need tovalidate these parameterisations.
Recent advanced parallel super computers (such as the
Earth Simulator in Japan) will enable the development andutilization of very high resolution climate models and very
complex earth system models including atmosphere, ocean,land surface, chemistry, biosphere, cryosphere and so on.
Such models will undoubtedly open the door to a new areaof study in the earth sciences and lead to new findings andunderstanding as results from the next generation of instruments measuring the atmosphere are established.

fore been exposed and the repercussions need definitive evaluation. Only through the development and application of ahigh resolution integrated global modeling and observation
system can our influence on the climate and environment be
estimated. A better understanding of sources, processes andcouplings between different parts of the climate system is required so that anthropogenic effects can be accurately andefficiently represented in models. Data from the next generation of Earth Observing Satellite programs (section 7.4)
and the use of ultra high resolution computer models will undoubtedly aid in the unraveling of our effects upon the environment.
Atmospheric Science in Environmental Issues
The atmospheric sciences are a vital component in the control of environmental issues, e.g., in the monitoring of pollution and greenhouse gases. As certainty in causes of climatechange improves, the thresholds of tolerable risks due to projected climate change need to be defined and the communication of scientific results to both society and policy makers
improved. The management of water resources is another environmental issue in which results from atmospheric physics
research have an integral role to play.
In both cases our understanding of the processes involved
needs furthering so that we are in a position to convince policy makers. Policy makers have many factors to consider intheir decisions and policy changes cannot be expected until
we can provide them with results based upon reliable prediction.

Improve Understanding of Anthropogenic Effects upon
the Atmosphere
Global climate change has attained enormous interest due toits potential to effect human activities and the environment. A
critical issue is to understand the possible anthropogenic rolein climate change.
Human-induced changes in climate observed on decadal
time scales are already evident. Atmospheric pollution now
hangs over many regions of the Northern Hemisphere. The
thinning of the stratospheric ozone layer, most notably over
Antarctica, is a human-caused feature of the planet. The
greenhouse gases being added to the atmosphere will residethere for decades to centuries and are predicted to increase
average global surface temperatures by several degrees, achange that is larger than the natural variation occurring overthe past 15,000 years. Precise understanding of the effects ofhuman influence on the environment and the communicationof theses results to policy makers is essential. The separationof natural climate change from that caused by the activities ofhumans needs to be established before the onset of a dynamicthat is irrevocable.
Research is continuing into the coupling between climate
and anthropogenic influences, e.g., Giorgi and et al. [2001].
Our anthropogenic emissions are often from highly localised
sources and experience highly non-linear interactions. We
are subjecting our planet to forcings to which it has never be-

Regionalisation of Climate Change Projections
As the climate changes, there will be significant differences
between regions Giorgi and Mearns [1991]. Climate predictions, hence, require regionalisation, in terms of impacts andvulnerability.
Regional climate is often affected by forcings and dynamics on a sub grid coupled Atmosphere-Ocean GCM(AOGCM) scale. Much of the current difficulty lies in extracting fine scale regional information from coarse scale
AOGCMs. Improvements in the resolution of climate models
as computing power increases will also aid in the regionalisation of climate change predictions.
Land Surface Effects on Climate Variability
Understanding land-atmosphere interactions and their effecton climate variability is an important area in climate modeling. The effect of the coupled terrestrial biosphere and global
atmosphere on climate change requires investigation, particularly with regard to its effect on the hydrologic cycle, heatand momentum fluxes and increases in atmospheric CO 2 Entekhabi et al. [1992]; Randerson et al. [1997]. Variability
in properties such as topographic height, vegetation cover,67

soil properties and snow cover occur at all length scales andcombine non-linearly. The accurate modeling of surface processes is thus strongly constrained by horizontal resolution.
Explicitly resolving finer scale features will lead to many improvements in the simulation of climate. The use of remotesensing data from missions such as Terra will also significantly enhance current knowledge in concert with data fromother land surface experiments.

bureau of IAPSO.
Improve Uncertainties in the Hydrologic Cycle
Deficiencies in our understanding of the global water cycle
severely handicap efforts to improve climate prediction andguide water resource planning. Significant problems in climate modeling are underpinned by our limited ability to understand and model cloud processes (section 7.3.1) and thehydrologic cycle Stephens et al. [1990]. Clouds are strong absorbers of infrared radiation, thus driving the greenhouse effect. Water vapour is the largest component of the greenhouseeffect, and hence the strongest determinant of the Earth’s surface climate. Changes in precipitation distributions are likely
to have significant impacts on future climates, especially inthe form of water stress. Any adverse effects can be expected
to be borne by those countries already facing serious water resource constraints. Model prediction of changes to the globalhydrologic cycle are still not reliable due to the non-linear
response of precipitation to changes in forcing/temperature.
This is illustrated in figure 7.3.2. It is clear that trends inglobal-mean temperature are predicted much more accurately
than trends in precipitation. It is still proving difficult to isolate the anthropogenic contribution to changes in the hydrologic cycle, which seems to be dominated largely by natural forcing. Measuring and forecasting spatial and temporal
patterns in water vapour and clouds are hence essential to address climate, water resources, and ecosystem problems Allenand Ingram [2002]; Lindzen [1994].
Research is in progress in trying to improve our knowledge of cloud processes and the water cycle (section 7.3.1).
Through these undertakings, the urgent requirement for uncertainty reduction in climate prediction will be greatly aided.

Climate and the Ocean
The ocean plays a critical role in the physical and biogeochemical dynamics of the ocean/atmosphere system.
Through heat exchange and freshwater transports, theoceans perform an active role in driving longer term atmospheric variations. The ocean also has a significant role inbiogeochemical dynamics, particularly in the carbon cycle
due to the dissolution of CO2 in water and the release ofdimethlysulphide by plankton. Climate is additionally hugely
effected by sea-ice due to its consequences for ocean water
masses. Correct parameterisation of this is needed, which requires high resolution atmospheric and oceanic fields.
The ocean feedback to climate must ultimately be manifested through air-sea exchanges and these interactions require further study. Some phenomena over the ocean that require study are the vertical exchanges of heat, moisture andenergy across the planetary boundary layer, boundary layer
clouds, tropical convective clouds and midlatitude convective
systems.
Coupled climate models certainly require an increase in
resolution from ∼ 1◦ to <∼ 1/3◦ . This resolution increase
is required in order to adequately capture eddies in the ocean.
Planetary Rossby waves are also a key component of ocean
circulation and may play a critical role in setting the timescale
for coupled modes of variability. Rossby wave propagation
speed and amplitude could be very different in ocean models
with different resolutions. Models hence need to be tested incomparison to available data.
Better historical heat content estimates for the ocean would
improve Ocean General Circulation Model (OGCM) validation. New remote sensing data and in-situ measurements (forprobing deeper into the ocean) will also augment OGCM performance and thus the understanding of the of the oceans inclimate. Instruments, such as TOPEX/Poseidon, are used to
study large scale circulations, infrared sensors, such as theAdvanced Along-Track Scanning Radiometer (AATSR) provide data on sea surface temperature, Scatterometers, such as
Seawinds, supply sea wind data, passive microwave radiometers, such as AMSR-E, are used to calculate latent heat fluxes
and ocean color sensors such as SeaWiFS, provide basic information on biological processes. These data sets, whencombined with models, will allow a systematic investigationof the coupled atmosphere-ocean system.
The ocean is dealt with in considerably more detail by the

The Carbon Cycle and Climate
Carbon cycle feedback has a very important influence on the
climate. The magnitude of this feedback is uncertain and depends strongly on the response of soil respiration to temperature, ocean exchanges and other processes, all of which require research.
The Effects of Solar Variability on the Global Climate
SystemThe effects of solar variability on the climate may be significant and must be differentiated from other natural influences
and from climate effects associated with human activity.
Improved understanding of solar influences on the tropospheric and stratospheric circulation and the climate in general is needed Labitzke and et al. [2002]. Several experiments
such as Earthshine (proposed) will greatly help in characterising the solar influence on our atmosphere and climate Lockwood [2002].
68

Figure 7.1: Changes in observed global-mean temperature and land precipitation over the last 55 years compared with a climate
model. After Allen and Ingram [2002].

Summary

E-science Enterprises

The overarching short-term aim of climate modeling is to reduce the uncertainties (beyond those inherent in the system)in climate prediction, hence increasing the value of the predictions to society. Uncertainties must be quantified, allowing
useful communication of information to end users and policy
makers.
Construction and evaluation of higher resolution models
that are increasingly comprehensive, incorporating all the major components of the climate, are needed as we aim to predict the future climate with greater accuracy. Current resolutions do not represent many processes within the climate
system sufficiently well. In addition to improvements in resolution, there needs to be a complimentary set of developments in the parameterisations included in models. Recent
advances in computing power should facilitate the construction of higher resolution models with the prime focus for research being the continuation and expansion of efforts to elucidate key climate processes, both chemical and dynamical.
The creation of a permanent global climate observing system is required in order to improve climate change prediction and thereby allow for regionalisation. This can only beachieved if the major global climate forcings and radiative
feedbacks are monitored with adequate precision. This would
allow for tighter constraints on possible trends in future climate. The extension of the observational climate record
through the development of integrated historical and current
data sets will also contribute by allowing a greater probabilistic certainty in climate prediction. This could also be aided
by comparative planetology.
There is still great uncertainty in climate prediction but

Current and anticipated advances in network technologies are
opening up new avenues for scientists. Chief among these is
the development of e-science or GRID technologies. GRID
projects are based on making use of high speed network connections, distributed data and software to enhance scientificresearch.
Two very different e-science projects, which perhaps give an example of the breadth of these emerging technologies, are the Earth System Grid [seehttp://www.earthsystemgrid.org/] and climateprediction.net[see http://www.climateprediction.net/]. The Earth System
Grid seeks to build a community wide resource from verylarge sets of climate model data and analysis software, enabling climate scientists to perform research more efficiently
and at a greater depth. Climateprediction.net, on the other
hand, makes use of distributed computing techniques to
produce a very large ensemble climate forecast, generated
by perturbing both model parameters and initial conditions.
The general public will shortly be invited to participate inclimateprediction.net, performing pre-packaged (10-100year) simulations with the ultimate aim of establishing the
spread of forecasts of 2050 climate consistent with current
observations and recent climate change.
These are just two among many exciting projects, whichseek to exploit emerging technologies to enable us to enrich
our scientific knowledge in new ways.
69

significant progress is being made as the underlying physics
of the atmosphere is better understood and implemented intomodels IPCC [2001].

7.3.3

Atmospheric Dynamics and Meteorology

Along with chemical processes in the atmosphere, dynamics
provides the building blocks of the atmospheric sciences. Improvements in our knowledge over the last decade have leadto dramatic reduction in forecast errors over all timescales.
This field of research is key to our quality of life and everyday
comfort. The capabilities of meteorology are already impressive but there exist many areas that allow for improvement.
Forecasting

Figure 7.2: The evolution of forecast skill for 500hPa height
forecasts, for 3, 5 and 7 day forecasts for both the Northernand Southern Hemispheres. Figure reproduced with kind permission from ECMWF.

Reliable forecasting is becoming increasingly important tosociety especially as regards its effect upon energy, health andagriculture. Accurate weather forecasting allows a greatercertainty when planning ahead. It also benefits the management of water resources and other elements having a direct
influence upon the sustainability of both our environment andour economies.
The skill in forecasting has improved dramatically over thelast 20 Years, and today, we enjoy considerable confidence
in predictions from periods of days to years. Other, moreadvanced, measures of forecast skill exist today, but as an illustrative example, figure 7.2 shows the increase in forecast
skill for 500hPa height forecasts. Whilst forecasting skill has
improved dramatically, the useful range of forecasts is currently of the order of a week. Extension of this range fromweeks to months is the next hurdle in forecasting. In orderto achieve this, the resolution of models will need to be improved in order to give a better representation of physical processes, particularly in the coupling of the ocean, atmosphereand land-surface. Progress in numerical weather forecasting
will be made as improvements in the way that physical processes are treated are improved and then incorporated into
the models. Some models are now fully non-hydro static and
it is the parameterisation of sub grid scale processes that require most research. New models for rainfall accumulation,
surface hydrology, convective weather and cloud diagnosis
have all aided in improving forecasting performance MetOffice [2002]. Prediction and modeling of cloud cover and cloud
condensate certainly needs improving. New schemes for the
temporal evolution of cloud fraction and condensate are being
developed but require more research (section 7.3.1).
Many problems in forecasting will also benefit from proposed developments in the processing and assimilation ofsatellite data, especially in the direct assimilation of radiances
into models. Meteorological observing systems continue toexpand and improve as observations throughout the world are
becoming more thorough and co-ordinated through undertakings such as the Working Group for Planning and Implemen-

Figure 7.3: The relative importance of different observation techniques in forecasting. The effects of the removal ofsatellite (NOSAT), aircraft measurement (NOAIREP) and radiosonde (NOUPPER) data sets from a forecast of 500hPa
height are shown. Figure reproduced with kind permission
from ECMWF.
tation of World Weather Watch. Many surface observations
are becoming automated with significant success. Observation times are also being reduced. Remotely sensed data is
now by far the most significant data set in forecasting. Figure
7.3 shows the effect on forecasts caused by the removal ofcertain data sets.
The importance of remotely sensed satellite data is clear.
New satellite programs such as Meteosat Second Generation (MSG) and EUMETSAT Polar System (EPS) will further help in improving forecasts. Additionally, Radio-sonde
and aircraft data remain highly important, especially for wind70

and relative humidity measurements, and must not be allowed
to deteriorate.

fluxes, and what role is played by tropical to extra-tropicalexchanges?
Research in the area of climate dynamics will be helped by
new observations and by high resolution simulations.

Synoptic Meteorology
Recent research has dealt with such diverse subjects as largescale tropical and subtropical disturbances, extratropical cyclones, polar lows, the interactions between tropical and extratropical systems, and the large-scale effects of volcanic
eruptions. The understanding and modeling of these large
scale effects will improve in direct correlation with the resolution and integrity of atmospheric models.

Global Changes in the Middle and Upper Atmosphere
Global changes in the middle and upper atmosphere, in response to both natural and anthropogenic influences, havesignificant effects on the lower atmosphere. The middle atmosphere is a highly coupled system in which dynamical, radiative and chemical processes are intimately connected. Important radiative roles are played by CO2 and O3 . Exchanges
with the troposphere and higher atmospheric levels are also
important, and it is vital that these processes are understood.
An approach involving data from satellite programmes, suchas EOS, and sophisticated models are required to understandcirculation, chemical, dynamical and radiative processes andhorizontal and vertical coupling mechanisms.

Improve Predictability of Extreme Weather Events
Extreme weather events are at the heart of some of theplanet’s most devastating natural disasters. The ability to predict these events and minimize their effects is vital. Progressin the study of atmospheric interactions that shape weather
phenomena has created the opportunity to make major advances that have lead directly to improved weather warnings
and predictions. This gives communities a greater confidence,
an improved chance of minimizing the effects of any extreme
weather events and hence a superior quality of life. New
models have the capability to run at horizontal resolutions ofaround 1km or less and open up the possibility of significantly improving predictions of severe weather. Increases incomputing power will probably be required before these highresolutions become fully operational. Elucidating relationships between extreme events and modes of climate variability, such as ENSO, will also be vital.

Boundary Layer Dynamics
Most dynamical processes driving global change relate tophysical-chemical-biological linkages, and exchanges of energy and materials across three main interfaces: between landand ocean, ocean and air, and air and land. As models are advanced and the effect of both horizontal and vertical resolution upon processes is established, it could well transpire that
greater vertical resolution is required in surface layers and theatmospheric boundary layer in order to represent processes
accurately. In order to improve these models, the dynamics
and transports associated with exchanges in the atmosphericboundary layer will need further investigation. Increases inthe vertical resolution of observations at interfaces might beneeded to validate models.

Atmospheric Dynamics Related to Climate Change
Several processes and feedbacks within the atmosphere require improved understanding. ENSO is the largest of thenatural climate fluctuations and is now qualitatively understood, but quantitative understanding is still weak, mainly because it involves interaction between sea surface temperature
anomalies and organised convection. It requires continued
monitoring due to its potential social and economic implications. Other important processes are the North Atlantic Oscillation (Hurrell [1995]), the Arctic Oscillation and the Madden Julian Oscillation. There are many possible mechanisms
at work and continued observations and modeling efforts are
required to illicit the actual feedbacks responsible.
Research is also required into the dynamics and transports
in the tropics. The tropics act as heat source regions that drive
global atmospheric circulation. Understanding short-termchanges in our climate requires an improved understanding of
the mass and heat balances of the tropics. For example, what
processes maintain the western Pacific warm pool, and whatis the role of El Nino Southern Oscillation (ENSO) eventsin this maintenance? What role is played by surface heat

Convection
Convection plays an important role in the surface heat budget
and whilst understood, is poorly characterised in most models. Deep convection and stratosphere troposphere exchanges
have a great effect on the atmospheric vertical profiles of tracegases and aerosols. Organised convective transport processes
develop on small scales but are globally important. These
smaller-scale hydrodynamic effects and non-hydrostatic motions are typically poorly represented in most GCMs. CO
is an excellent tracer of convective transport and CO datafrom several satellites will help in improving current convective models.
Atmospheric Electricity
Although the existence of the global electric circuit has been
known for many decades, most recent research has concentrated on the ’generators,’ i.e., the thunderstorms. There are71many knowledge gaps concerning, for example, the contribution of other generators, such as the solar-wind and the upper
atmosphere tides.
Projects, such as the U.K. Met Office long-range lightning
detection system, will allow the original position of lightning
discharge to be located with an accuracy of between 2 and
5km over most areas of Europe. In addition, experiments
studying the sun, such as SOHO, and those studying the interactions of the sun with the thermosphere, such as TIMED[see http://www.timed.jhuapl.edu/], will allow for improved
characterisation of the causes and effects of atmospheric electricity.

proved forecasts of convection, precipitation, and seasonal
climate.
All of these efforts will likely be benefitted by e-science enterprises and the improvements in computing capacity in thenext few years. As computing capacity increases, so models, parameterisation and observations must be ready to fully
exploit the advances.

7.3.4

Planetary Atmospheres

Other planets in the solar system and beyond provide atmospheric scientists with full scale laboratories in which to test
dynamical, chemical and climate theories. Missions proposedover the next few years will provide more data to improveplanetary GCMs and aid in comparative planetology.

Understanding the Nature and Characteristics of Turbulence in Rotating Fluid Motion
Underpinning the study of atmospheric dynamics is the studyof fluid flow and particularly turbulent motion. Further,laboratory-based study of the dynamical processes occurringin the atmosphere is needed alongside the continued modeling efforts.

Establish Climate Histories and GCMs of Earth, Mars,
Venus, and other Planets
Regarding the aim of a sustainable Earth, the atmospheric sciences can also contribute to understanding how our planet islikely to develop over the coming centuries through comparative planetology. This provides an excellent base for the studyof other atmospheric regimes and provides additional understanding on how our planet might develop. In the reconcilingof GCMs of the terrestrial planets, significant information canbe attained, particularly in terms of greenhouse (radiative energy balance) models, that can help determine the stability ofpast, present and future climate on Earth. The gas giant planets also pose noteworthy research problems for the future.
In order to facilitate the understanding of other planetarysystems, a greater emphasis must be placed upon planetary
missions. Systematic measurements are required, utilizing
both orbiters and landers and will pose problems from botha scientific and engineering perspective. Missions proposedover the next decade will begin to address this lack of data forboth Mars and Venus.

E-science and Computer-to-Computer Communication
Weather-dependent enterprises could incorporate atmospheric information more readily into their decisions withgreater computer-to-computer communication and increased
ease of access to electronic resources. The atmospheric sciences should aid in this process wherever possible. The world
data center system, created through the international councilof scientific unions, is one such undertaking that benefits atmospheric scientists and could be used as a model for further
initiatives. The meteorological community also relys upon
fast exchange of observational data on a national and international scale. Use of internet protocol standards has alreadyallowed for much speedier and reliable exchanges of data. It
is important that the atmospheric sciences remain up to datewith advances in communications and utilise all of these in
the progression of research.

Climate Conditions for Life Elsewhere in the Galaxy

Summary

Assessing the possibilities for life elsewhere in the Galaxy
is a growing area of interest and is important if the goals ofsection 7.2 are to be realised. Several projects looking for
extra solar planets are currently in progress.

Better utilization of data, including the determination of optimal combinations of available and new observations areneeded to enhance research in atmospheric dynamics and meteorology. The deterioration of the global radio sonde network and other in-situ measurements needs halting. The advances in satellite programs will also continue to assist in
further research in dynamics and meteorology. New satellite instruments will provide data with global coverage and a
vertical resolution that will be essential as modeling exercises
move to higher resolution in order to model the processes in
the atmosphere. Furthermore, observations and understanding of boundary atmosphere interactions will be key in im-

Summary
An increased number of planetary missions and greater emphasis on comparative planetology will afford much additional insight regarding the Earth and provide the foundations for development of new habitable environments on otherplanets .
72

7.4 Recommendations for the Atmospheric Sciences

In developing Earth system models, subsystem models on vastly differing scales, both temporal and spatial, must be reconciled and combined. In the testing and integration of these models, much greater coordination and co-operation is required between fields
within the Earth sciences. SOLAS (Surface OceanLower Atmosphere Study) is an example of an interdisciplinary and international investigation of the dynamic
processes occurring across the sea surface with the
IGBP (International Geosphere Biosphere Programme)
co-ordinating several other efforts in the research ofboundary-atmosphere interactions. These types of undertakings will be essential to accelerated progression.

Recommendations for Moving Towards Higher Fidelity
ModelsProgress toward the goal outlined in section 7.2 is accelerating rapidly as the atmospheric science community is beginning to develop techniques to utilise the vast increases incomputing power that are becoming available today. The realisation that as greater computing power becomes available,
the best way to exploit this is not just to run current models forlonger, or more often, but to improve the fidelity, spatial andtemporal resolution of models, is going to lead to huge developments in the atmospheric sciences in the next few years.
The linkage between the Earth and its atmosphere is theultimate symbiotic relationship. Atmospheric studies are being shaped today by the recognition that contemporary approaches must seek to understand, model, and predict allcomponents of the Earth’s environment, including coupling
between various systems. Critical scientific questions focus
on the exchanges of energy, momentum, and chemical constituents between the troposphere and the surface below, as
well as with the layers above. In addition, many processes
within the atmosphere itself, such as cloud processes andchemical transport, are not adequately represented in current
models. Parameterising all of these processes and elucidating
their resolution dependence, along with an understanding ofprocesses coupling different spatial and temporal scales, willbe the primary research focus over the next decade.
The over-riding recommendation for the atmospheric sciences is hence to improve co-ordination and co-operation in
the development of high resolution Earth System Models bothfor climate research and short-term forecasting.
A few other general recommendations for the atmosphericsciences, aimed at moving toward the development of higher
fidelity models and ultimately the realisation of the goal outlined in section 7.2 are given below.

• Use of Contemporary Numerical Computer Models
The atmospheric sciences must ensure that the most contemporary computing facilities are used along with models that fully utilise the capacity available. The parameterisations required for higher resolution investigations
should be developed in advance of increases in computing power so that they can be fully exploited as theyarise.
• Integrated Global Observing Systems
The increasing importance of integrated observation systems and new observations of critical variables is clear.
Ultra-high resolution satellite data is becoming important as models progress toward greater resolution. The
global coverage possible from satellites is vital, but highresolution in-situ measurements are also needed, particularly for interactions and exchanges at the boundariesof the atmosphere. An increase in the number of surface
exchange measurements will aid research, especially if
the vertical resolution of models at boundaries is enhanced. The atmospheric science community should develop a plan for optimizing global observations of theatmosphere, oceans, and land. This plan should take
into account requirements for monitoring weather, climate, and air quality and for providing the informationneeded to improve predictive numerical models used forweather, climate, atmospheric chemistry, air quality, andnear-Earth space physics activities. Both NASA’s Earth
Science Enterprise and ESA’s Living Planet program aresignificant steps toward reaching this goal NASA [1999];
ESA [1998]. Development of commercial remote sensing ventures might also be considered.

• Improve Communication and Co-ordination with Scientists Studying other Elements of the Earth System
As models progress to greater resolutions, so better simulation of the complex behavior of the full Earth system is required. It is the fluxes of materials and energy between the atmosphere and the oceans, the land,
the ecosystems, and the near-space environment that define the structure and evolution of atmospheric processes
and events. Most goals of research in the atmosphericsciences are likely to require considerable collaboration
with a broad range of other geoscientific disciplines. By
moving toward higher resolution in atmospheric models, the gap will be narrowed between climate modellers
and scientists specialising in other aspects of the Earthsystem, so aiding better integration.

• Data Assimilation
The maximum amount of information must be extracted
from observations. This requires continual adaptations
and advancement of assimilation techniques. The quality of both observations and modeled data needs thorough assessment in optimal assimilation techniques.
Current systems such as the 4-D Var system of the U.K.
73

Met. Office provide an excellent model for assimilation
into forecasts. Efficient assimilation of data into climate
models requires similar thought.

these, real progress is likely to be made in the basic understanding of atmospheric processes. In challenging ourselves
and taking a truly long-term view, not only will great strides
be made toward achieving the conclusion of the projects
themselves, but new perspective and insight into more shortterm problems will also be revealed. Conservatism has neverbeen a friend of research.

• Laboratory Based StudyIn elucidating key chemical processes and transports
in the atmosphere, laboratory based study of chemicaland dynamical processes needs to be continued and enhanced. As models begin to require improved parameterisations on higher resolution grids, so tests of theseparameterisations in the laboratory will be needed as anintegral part of the validation process.

• Intentional Forcing of the Atmosphere
It would be irresponsible in the extreme to begin forcing our atmosphere at the present time with our limited knowledge of exactly what the consequences mightbe. However, this is something that society should certainly consider in the future. Being able to modify the
chances of precipitation or null the onset of extreme
weather would certainly be of benefit to society. Research should be starting now with both computer andlaboratory based simulations. The study of point-likeforcings, such as volcanic eruptions and anthropogenic
emissions, will also aid in the development of our ability
to effect a positive influence of aspects of our environment.

• Database Management
One of the limiting factors associated with climate models at the present time is data with which to validate results. A concerted effort in the development and maintenance of spatially and temporally resolved chemical andclimatological databases will be central to the validationof models in the future.
• Mathematical Techniques
Perhaps the most challenging aspects of developing
higher resolution models are the mathematical techniques required to bridge the gaps between disparate
spatial and temporal scales associated with different processes in the atmosphere and at its boundaries. Adaptive gridding schemes, which employ a combination ofnested static and dynamic grids, which can each run attheir own optimal timestep, promise to significantly increase the performance of models. The development andvalidation of mathematical techniques is vital.

• Location and Development of Alternative Habitable Environments
As previously mentioned, several projects are alreadyunderway into the detection of Earth-like planets aroundother stars. This type of undertaking is vital along withincreased investment in the engineering capabilities required to inhabit another planet. In addition, establishing terraforming projects would possibly be of hugebenefit to both society and the atmospheric community.
Through these types of projects, significant information
will be returned about different couplings within the
Earth system along with detail about how to maintaina habitable environment, which has to be our ultimate
aim.

• Increased Emphasis on Comparative Planetology
In understanding processes in the atmosphere and modeling climate changes, there is a vast amount that could
be gained from an increased use of comparative planetology and exchange of results between planetary and
Earth scientists. As models of processes within the Earthsystem are improved to higher resolution, the ability tocompare the effects of different parameters on couplings
within the atmosphere that is provided by comparative
planetology will be invaluable.

Other Recommendations for the Atmospheric Sciences• Greater Use of E-Science• Increase Public Information and Communication

In the modern era, a greater use of the freedom of information provided by the electronic age would be invaluable in the atmospheric sciences.

The atmospheric sciences should improve presentationand communication of results to society and policy makers. We are all subjected to much misinformation about
the dangers of climate change Lomberg [2001]. This isparticularly important when relating details of extreme
weather events to the general public. Uncertainties on
projections of weather and climate need to be quantified
and properly represented to the public and policy makers.

Recommendations for Realising Long-Term Projects
Whilst we are not currently in the position to realise the longterm projects outlined in section 7.2, significant progress canalready be made, and the foundations for future research established. Through the undertaking of ambitious projects like74

7.5 Conclusions

IPCC, , Climate change 2001: The scientific basis, Technicalreport, IPCC, 2001.

Many important and challenging opportunities are facing theatmospheric sciences. As the resolution and fidelity of atmospheric models and observations improve and atmosphericprocesses are better understood, the accuracy and resolutionof atmospheric prediction will be enhanced. As a consequence, society will enjoy greater confidence in atmosphericinformation and will be able to act more decisively and effectively. Through the adoption of a forward thinking approach
the IUGG will have a significant role to play the realisationof this vision.

Liou, K. N., Influence of cirrus clouds on weather and climate
processes: a global perspective, Mon. Weather Rev., 114,
1167–1199, 1986.

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Penner, J. E., and et al., Aerosols, their direct and indirect
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Ehhalt, D., M. Prather, and et al., Atmospheric chemistry
and greenhouse gases, In Houghton, J. T., and et al., editors, Climate Change 2001: The Scientific Basis. Cambridge University Press, 2001.

Pope, V. D., and R. A. Stratton, The processes governing
horizontal resolution sensitivity in a climate model, Clim.
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Entekhabi, D., I. Rodriguez-Iturbe, and R. L. Bras, Variability
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Prentice, I. C., and et al., The carbon cycle and atmosphericcarbon dioxide, In Houghton, J. T., and et al., editors, Climate Change 2001: The Scientific Basis. Cambridge University Press, 2001.

ESA, , The science and research elements of ESA’s living
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76

Chapter 8International Association of Geomagnetism andAeronomy
A. J. Ridley

processes which have a dramatic impact on our spaceenvironment.

The International Association of Geomagnetism andAeronomy (IAGA) is focused on understanding the nearEarth space environment. This ranges from studying the dynamics of the core magnetic field of the Earth, to the chemistry, dynamics, and electrodynamics of the thermosphere andionosphere, to the interaction between the Earth’s magnetic
field with the Sun’s atmosphere and magnetic field, to theSun’s atmosphere, and finally to the Solar dynamics which
ultimately drive most of the science in the near-Earth spaceenvironment.

2. Understanding reconnection. While this process issomewhat understood in general terms, the specifics are
not understood enough to predict when and where reconnection will take place in 3D. This means that a number of processes on the Sun and in the Earth’s magnetosphere can not be fundamentally understood. For example, the explosive reconnection in the Earth’s magnetotail (i.e., substorms), or the explosive initiation of coronal mass ejections on the sun are not well understood atthis time. Once reconnection is understood thoroughly,
substorm and CME initiations will most likely be understood.

8.1 Long-term Goals
In order to lead an international effort on the understanding of
this extremely large physical system, it is important to have along-range strategy outlined. This long-ranged strategy helps
to keep the research community focused on the central goals.

8.1.1

3. Cross-scale processes in the ionosphere and thermosphere. It is known that auroral arcs can be very narrow and intense, but it is not known what effect thosearcs have on the regional or global structure of the ionosphere. In addition, the entire high-latitude energy deposition is known to influence the global thermosphereionosphere system, but the time-scales of the influence,as well as the dynamics and chemistry, are poorly understood. As another example, the large-scale thermospheric and ionospheric structures are known to cause
small-scale events, such as ionospheric scintillation.

Focus Areas

Because IAGA includes such a diverse community, there are
a number of long-term goals. Most of them can be describedas having a complete understanding of the near-Earth spaceenvironment. Specifically,
1. Understanding the mechanism for the reversal of theSun’s magnetic field every 11 years and the flux emergence from the convective zone into the corona is of primary importance. While this process is far away from
Earth, it sets up the solar wind structure and therefore
plays a crucial role in determining the magnetosphericand ionospheric conditions. Understanding these processes would allow solar physics to begin to predict
when and where coronal mass ejections may occur,
where corotating interaction regions may be, and other

4. The changing magnetic field of the Earth. In order tounderstand the long-term stability of the magnetosphere,
it is important to understand the processes that create themain field.
Benefits to Society
Satellites cost millions of dollars to build. Satellites can bedamaged or even destroyed by a number of phenomena that
occur in the near Earth space environment, such as radiation77

erosion of electronics, charging of space craft and subsequentarching, which may occur, and the ejection of the space-craftfrom the magnetic stability region of space.
Understanding of the near-Earth space environment is quite
important because of the increasing number of space assets,
the significant cost of launching satellites, and the monetaryinvestment in developing and building these satellites

Tn at 124.6 km Altitude

500

450

8.2 Short-Term Priorities
8.2.1

400

18

Thermosphere and Ionosphere

Prediction of ionospheric scintillation formation.
Ionospheric scintillation occurs when the ionosphere becomes unstable to the Rahliegh-Taylor instability. The main
mechanism for this instability is thought to be understood,
but the prediction of exactly when and where this occurs is
not perfected. Scintillation basically creates giant plumes ofionospheric density at very high altitudes (∼ 300 km) Tsunoda [1988]. These enhanced densities cause significant radarback scatter and make high-frequency communication nearly
impossible. It is therefore important to understand when andwhere scintillation will occur.
Influence of gravity waves on ionospheric structure.
It is known that mesospheric gravity waves propagate
up to the thermosphere, and that these waves can causesignificant changes in the chemistry and dynamics of thelower thermosphere [e.g. Fuller-Rowell [1994]; Hickey et al.
[1992]]. Gravity waves can therefore affect the ionospherealso through chemistry and ion neutral drag forces. Whenthe gross structure of gravity waves is well understood, theexact global structure is not. In addition, the quantificationof the effects upon the ionospheric structure and dynamics
needs to be completed. This will most likely be done throughthe use of global thermosphere and ionosphere models whichhave a more accurate gravity wave structure included. An effort is underway at the National Center for Atmospheric Research to build a whole atmosphere community climate model(WACCM) which will model from the troposphere throughthe thermosphere. This model will include all of the largescale waves which propagate upward into the thermosphereand ionosphere.
Dynamics and chemistry due to Joule heating.
With the launch of the TIMED satellite, quantitative understanding of thermospheric Joule heating has become possible
at small spatial scales. Joule heating is caused by ions colliding with neutrals, which are moving with a different velocity.
This heating occurs in regions in which there is significant
ion density and differential motion [e.g. Ahn et al. [1983];
Foster et al. [1983]; Chun et al. [1999]]. The heating causes
the thermosphere to expand and waves to be launch fromthe polar region towards the equator. The expansion of thethermosphere can increase satellite drag and can cause ionospheric outflow, which adds particles to the ring current pop-

350

00

300

Figure 8.1: This figure shows the thermospheric temperature
structure at 125 km altitude above the North polar region.
The top of the plot is towards the Sun while the left side isdusk. Each circle is 10◦ , while the outer circle is 40◦ geographic latitude. The enhanced temperatures are caused by
Joule heating.
ulation. The propagating waves are typically called travelingionospheric disturbances, and cause problems with high frequency radars and communication devices. Figure 8.1 shows
the thermospheric temperature structure during a storm which
took place on May 4, 1998.
Investigation of small scale structures in global models.
A number of global models of the thermosphere – ionosphere system exist today. One of the most important models of the thermospheric region is MSIS [Hedin, 1983, 1987,
1991]. MSIS is an empirical model which relates the neutral
densities and temperature to F 10.7 and Ap. It uses a spherical harmonic fit of many different satellite and remote observations. It is considered one of the more important models
because of the amount of data which has gone into the model,
and therefore it is felt that it represents the average conditions
for the given inputs. MSIS has been improved by adding timedependence, which allows storm periods to be modeled moreaccurately.
The international reference ionosphere (IRI) is similar to
MSIS, but for the ionosphere [Rawer et al., 1978; Bilitza,
2001]. It models the ionospheric density and temperatures
for all latitudes and local times, but does not include any auroral precipitation, which makes the model incorrect in theauroral regions for medium and strong auroral activity.
Other types of thermosphere or ionosphere models are the78first principle models which model the different regions bydetermining the density, momentum, and energy of the fluid
self-consistently. The T-GCM (TGCM, TIGCM, TIEGCM,
TIMEGCM) series of models are examples of such models
which were created at the National Center for AtmosphericResearch. These models solve for mass mixing ratios of theneutral major species O2 , N2 , and O and the minor species
N(2 D), N(4 S), NO, He, and Ar. They are full 3-dimensional
codes with 5◦ latitude by 5◦ longitude by 0.5 scale height altitude cells [Dickinson et al., 1981, 1984; Roble et al., 1988;
Roble and Ridley, 1987; Richmond et al., 1992; Roble and Ridley, 1994]. A different first principles model is the Coupled
Thermosphere Ionosphere Model (CTIM) [Fuller-Rowell andRees, 1980, 1983; Rees and Fuller-Rowell, 1988; Rees. andFuller-Rowell, 1990].
Wang et al. [1999] and Wang et al. [2001] extended the
TIGCM to include a high resolution nested grid to resolvefeatures which are less than 5◦ in latitude or longitude. They
typically use the nested grid within the auroral region. The
maximum resolution of the nested grid is 1.3◦ .
In the next decade, it is expected that the global thermosphere - ionosphere models will attain much higher resolution than current models. This will allow for the investigationof how intense small-scale phenomena effect the regional andglobal environment. For example, auroral arcs are known to
be only a few tens of kilometers across down to meters acrossand can be associated with large electric fields and particle
precipitation fluxes. This causes intense heating in a very
localized environment, which may spread through diffusion
or may travel through waves. Current models can not comeclose to examining these types of effects.
Data assimilation.
There are currently only a small number of groups who
are actively attempting to perform data assimilation within
the thermosphere and ionosphere. The assimilative mapping of ionospheric electrodynamics (AMIE) technique ingests electrodynamic data to determine the electric field, particle precipitation, and current structure of the high-latitude
ionosphere [e.g., Richmond and Kamide [1988]; Richmond[1992]; Ridley et al. [1997, 1998]]. While this technique isquite useful, it only works on a 2-dimensional grid in thehigh-latitude region, and it only produces maps of electrodynamic quantities and not fundamental quantities such as
densities, velocities, and temperatures.
One group has started to incorporate measurements of total
electron content into a 3-dimensional model of the ionosphere[see http://gaim.cass.usu.edu/index.html]. This is being carried out by using data assimilation techniques developed inweather forecasting (i.e. Kalman filtering) and applying themto global simulations of the ionosphere. In the next decade, it
is expected that a number of other groups will begin to examine using Kalman filtering within thermosphere, ionosphere,
and magnetosphere codes.
Influence of Earth’s ionosphere and magnetosphere on thelower atmosphere.
Our understanding of how the magnetosphere influences
the mesosphere, stratosphere, and troposphere is quite limited. It is known that there is relatively little influence overthe period of days to weeks, but some correlation has beenshown to occur over decadal time periods. The most common
example of this is the Maunder minimum (1650-1710). Thisis a period of time in which there were very few Sun spots,
so the magnetic activity in the near-Earth space environment
was quite low. During this time, the Earth underwent a mini
ice age, which lasted about the same amount of time as the
low activity. The problem with this correlation is that the solar luminosity is also tied to Sun spots, so during this period,
the Sun may not have been heating Earth quite as much as it
normally does.
There is currently an effort underway to couple lower
atmosphere models to the T-GCM series of thermosphereionosphere models. This effort is called the Whole Atmosphere Community Climate Model (or WACCM). When thismodel is completed and applied to a large number of eventsor a large time period, research may begin to determine howmuch coupling actually occurs between these regions of ouratmosphere.
Prediction of ionospheric current structures.
The first order global ionospheric field-aligned current
structure was described many years ago [Iijima and Potemra,1976]. It is known that within this global structure there aremany other smaller structures. These small-scale structures
can be less that 100 km in latitudinal width and can movearound quite quickly. While the exact temporal and spatial
structure is difficult to study, the dynamics which control thismay be understood, and specifications of the types of structures (e.g. stable location versus highly variable location) are
important to learn about.
Space Weather.
There are a number of research groups which are starting
to run models in real-time, but have not fully validated them,nor do they insure that they will run automatically 24 hours
a day, 7 days a week. In the next decade, it is expected thata number of researchers will push their models to become
operational codes. This will allow space weather monitoring
stations, such as the Space Environment Center, to use a variety of different codes for determining the conditions in thenear-Earth space environment.
For tropospheric weather forecasting, a number of models
are run and are combined together to create an ensemble average forecast. It will most likely be a number of years before
this type of averaging can be done within the thermospheric- ionospheric community, but we expect there will be a lot ofprogress within this field.

8.2.2

Magnetosphere

Stability and dynamics of the magnetospheric tail79

Frame 001  4 Apr 2003  BATSRUS: Cut Y Data, 2000-03-24-08-55-00-500

Magnetospheric substorms are global events, which produce aurora near the Earth’s magnetic poles [as first describedby Akasofu [1964]]. Earth’s magnetospheric tail can grow to
be very long and thin (i.e. 1/2 Earth Radius) in Z. This thin
tail has a large gradient in magnetic field orientation, which
drives a strong cross-tail current (or vise-versa, depending on
your view point). At some point, the cross tail current becomes disrupted, and the current is diverted from the tail into
the ionosphere near the poles. This produces large auroral
displays near the current regions. Figure 8.2 shows the magnetosphere with a very long tail (possibly a highly energizedstate), and a short tail (a low energy state).
The exact mechanism, which causes the disruption of thecross-tail Current, is unknown. We list a few models of substorms here: the near-Earth neutral line model [e.g. Hones[1979]], the boundary layer model [Rostoker and Eastman,
1987], the thermal catastrophe model [Goertz and Smith,1989], the current disruption model [Chao et al., 1977;
Lui, 1996], the Magnetosphere – Ionosphere coupling model[Kan, 1993], and the interplanetary magnetic field triggered
substorm model [Lyons, 1995]. In addition, the current may
not disrupt over the whole tail; it may occur in localized regions [e.g. Lyons et al. [2003]], which complicates issues significantly since instrumentation, which measures these phenomena, is quite sparse. So, even identifying true globalscale events is problematic.
The search for reconnection continues.
One of the most important processes for transferring energy from the solar environment to Earth’s magnetosphere isreconnection [Dungey, 1961]. This process changes magnetic
energy into particle energy. The understanding of this process is one of the most fundamental for understanding how
the magnetosphere interacts with the solar environment. It
is not well understood. There are still controversies about
whether reconnection has to occur for antiparrellel magnetic
field lines or whether component merging can take place. In
the magnetospheric tail, the reconnection process and its relations to current disruption is even less understood (as discussed above).
With the launch of the Cluster satellites, a number of researchers have started to search for magnetospheric reconnection sites [e.g. Phan et al. [2003]]. Recently, researchers haveshown evidence that the reconnection site has moved over thecluster of satellites. Studies with the Polar satellite have also
shown evidence of crossing the reconnection region. More ofthese types of events will be found in the near future, and will
help us to address some fundamental issues in reconnection
theory.
Data assimilation.
Data assimilation within the magnetosphere is almost
nonexistent. There are a number of reasons for this: (1)lack of data to be assimilated; (2) the strong nonlinear processes within the magnetosphere; and (3) the strong spatial
discontinuities, which exist because of the magnetic field. It

80
70
60
50

Z [R]

40
30
20
10
0
-10
-20
0

X [R]

-50

Z [R]

25

0

-25

0

X [R]

-50

Figure 8.2: These two figures show examples of how the magnetospheric tail can be quite short (top) or long (bottom), depending on the interaction of the magnetosphere with the solar wind and IMF. The color indicates the density (different
scales), while the line traces are the magnetic field lines. The
black circle represents the inner boundary on the magnetospheric 3-D simulation. The Sun is off to the left.

is expected that over the next decade researchers will begin to
investigate the use of data within global and localized simulations of the magnetosphere.
Radiation belts.
The radiation belts are bands of very high-energy particles,
which are at relatively low altitudes (within approximately 2
Earth radii). Because of the altitudes of the radiation belts,
many orbital planes cut through them. The exposure of satellite electronics to these particles is highly degrading, and limits the lifetime of the satellite severely. It may would be use80

ful and important if in the future we could more accurately
predict the temporal and spatial specification of the radiation
belts [e.g. Elkington et al. [2003]]. This may allow satellite
operators to extend the life of their satellites.
Influence of the thermosphere and ionosphere on the magnetospheric dynamics.
Recently, researchers have started to examine more closely
how the ionosphere influences the magnetosphere. There are
a number of areas within this field which have been examinedon a small scale before. For example, it is well known that themagnetospheric ring current is partially composed of oxygen
atoms, which originate from the ionosphere. Therefore it canbe said that ionospheric outflow plays a role in the amount ofenergy that can be fed into the ring current.
Another example is the control of the thermospheric neutral winds over the ionospheric and magnetospheric dynamics. Thayer and Vickrey [1992]; Sánchez et al. [1998]; Thayer[1998] make use of the Sondrestrom incoherent radar to determine how the thermospheric neutral winds effect the energy flow from the magnetosphere to the ionosphere andback. Deng et al. [1991, 1993]; Lu et al. [1995] use a global
thermosphere - ionosphere model to determine the effect of
the neutral winds on the ionosphere. The models presented
by Peymirat et al. [1998], Peymirat et al. [2002], and Ridley et al. [2003b] show results of a coupled TIEGCM different magnetospheric models. These studies start to quantify
the effects of the neutral winds on the global magnetospheric
convection and configuration.
Fedder and Lyon [1987] showed that the magnetosphereis neither a current nor a voltage generator by using a
global MHD code by varying a constant ionospheric conductance to determine whether the magnetosphere would selfconsistently increase the field-aligned currents or not. Raeder
et al. [1996] showed that the ionospheric conductance specification is crucial in determining the temporal history of themagnetospheric dynamics. They showed that by changing the
conductance in the ionosphere, they could make the magnetosphere go into either a steady convection state or storageunloading state. Raeder et al. [2001] further describes how
the ionospheric conductance can determine the timing andstrength of auroral substorms through the use of a limited
parametric study. The study by Ridley et al. [2003a] begins to
examine the effect of the different ionospheric conductancepatterns on the global state of the magnetosphere.
One of the main issues with these types of studies is thelack of diverse measurement conditions to prove the cause
and effect statistically. This must change in order to determine how much of an effect the thermosphere - ionospheresystem has on the magnetosphere.
Energy flow through the magnetosphere.
Statistical studies have shown that embedded regions ofsouthward interplanetary magnetic fields with intensity B z <−10nT and duration of greater than three hours in the solar
wind produce major magnetic storms at Earth with Dst dip-ping below -100 nT [Gonzalez and Tsurutani, 1987]. The
physical mechanism underlying the energy transfer from thesolar wind to the magnetosphere is reconnection at the dayside magnetopause. These regions of strong southward IMF
are termed ”geoeffective” which is widely interpreted tomean that they create large geomagnetic storms. The intensity of the ring current enhancement is a primary measure of
the magnitude of the geomagnetic storm. However, the way
in which energy is distributed throughout the global magnetosphere in association with various types of solar wind transients is not known. Recent studies indicate that energy flow
through the inner magnetosphere and into the ring current
reservoir may account for as little as 20% of the total energy dissipated during a major magnetic storm [Kozyra et al.,
1998; Weiss et al., 1992]. If this is the case, then a large partof the magnetic storm energy is loaded into the magnetotail
lobes, lost downtail as plasmoids and dissipated in the auroral
ionosphere. It is possible that the majority of the energy input
during magnetic storms is contained in the highly disturbed
magnetotail configuration and dissipated in frequent and intense substorms. In fact, during the main phase of magnetic
storms, magnetic field depolarizations and substorm injection signatures are so frequent that identifying individual substorms is a nearly impossible task [c.f., Kamide et al. [1998]].
Night side growth phase and injection signatures sometimes
occur simultaneously, separated by only a few hours in local
time. This high number of substorm recurrences must leadto elevated stormtime plasma sheet temperatures and large
amounts of energy pumped into the auroral ionosphere.
Over the next decade, a major focus of magnetospheric research is going to be attempting to quantify how much energy is entering the magnetospheric system and partitioning
the loss of that energy into the different regions of the magnetosphere. Specifically, the IMAGE mission is examining
the ring current dynamics, while the TIMED mission is examining the energy deposition into the ionosphere. One of
the roles of the Cluster mission is to examine the dynamics ofthe plasma/current sheet, which will help to determine howmuch energy is flowing from the tail towards the Earth andhow much is being lost down tail.

8.2.3

The Sun and the Heliosphere

Helioseismology
The science studying wave oscillations in the Sun is called
helioseismology. One can view the physical processes involved in the same way that seismologists learn about Earth’s
interior by monitoring waves caused by earthquakes [Chaplin
et al., 2002; Dzhalilov et al., 2002]. Temperature, composition, and motions deep in the Sun influence the oscillation
periods and yield insights into conditions in the solar interior.
Because it is impossible to send satellites to sample the solar interior, helioseismology offers one of the only methodsof measuring the dynamics of the solar interior. Most of the81Figure 8.4: A magnetic field butterfly diagram. This image
shows how the magnetic field near the solar surface changes
as a function of time. Equatorward propagation of the magnetic field is evident.
when the dipole is highly tilted and the Sun is quite active,
large events are launched towards the Earth, and dramatic
magnetic storms occur. While there are a number of theoriesof why the dipole flips every 11 years, there is little agreement. This will continue to be a large topic in space research
until it is solved.
Coronal mass ejections
Coronal mass ejections (or CMEs) are huge bubbles of gas
threaded with magnetic field lines that are ejected from theSun over the course of several hours [Subramanian and Dere,2001]. Although the Sun’s corona has been observed during
total eclipses of the Sun for thousands of years, the existenceof coronal mass ejections was unrealized until the space age.
The earliest evidence of these dynamical events came fromobservations made with a coronagraph on the 7th Orbiting
Solar Observatory (OSO 7) from 1971 to 1973. A coronagraph produces an artificial eclipse of the Sun by placing an”occulting disk” over the image of the Sun. During a natural
eclipse of the Sun the corona is only visible for a few minutes
at most, too short a period of time to notice any changes incoronal features. With ground based coronagraphs, only the
innermost corona is visible above the brightness of the sky.
From space the corona is visible out to large distances fromthe Sun and can be viewed continuously.
CMEs disrupt the flow of the solar wind and produce
disturbances that strike the Earth with sometimes catastrophic results. The Large Angle and Spectrometric Coronagraph (LASCO) on the Solar and Heliospheric Observatory(SOHO) has observed a large number of CMEs (e.g. Figure 8.5). Understanding how CMEs occur and what triggers
them to erupt is very important to being able to predict when
there will be activity at Earth. It is similar to the substorm
research, which is being conducted in Earth’s magnetosphere- both are explosive events, which are possibly triggered. The
triggering mechanism is still unknown for both [Priest andForbes, 2002; Dikpati et al., 2002].

Figure 8.3: This image was generated by the computer to represent an acoustic wave resonating in the interior of the Sun.
Here, the radial order is n = 14, angular degree is l = 20,
and the angular order is m = 16. Red and blue show element
displacements of opposite sign. The frequency of this mode
determined from the MDI data is 2935.88 +/− 0.2 µHz.
physics of the Sun derives from its interior, so understanding
the interior is of primary importance. That makes helioseismology very important also. It is expected that techniques formeasuring the waves on the solar surface will improve overthe coming decade, so that determining the interior dynamics
will be much easier.
The Solar Dynamo
It is widely believed that the Sun’s magnetic field is generated by a magnetic dynamo within the Sun. The fact that theSun’s magnetic field changes dramatically over the course ofjust a few years, and the fact that it changes in a cyclical manner indicates that the magnetic field continues to be generated
within the Sun [Solanki et al., 2002]. The solar dynamo is responsible for several phenomena: 1) the 11-year period of
the sunspot cycle, 2) the equator-ward drift of the active latitude, 3) Hale’s polarity law and the 22-year magnetic cycle,
4) Joy’s law for the observed tilt of sunspot groups and, 5)
the reversal of the polar magnetic fields near the time of cycle
maximum.
The reversing of the Sun’s dynamo causes significant activity to occur on the solar surface every 11 years. When the
Sun’s magnetic field is close to dipolar, there is very little activity, but when the field is strongly tilted, there are many active regions and coronal mass ejections (see Figure 8.4). This
is of primary importance to Earth because every 11 years,
82

Researchers are just starting to incorporate solar energetic particles into global heliosphere models. Having CMEs
erupting into the global heliosphere will create large reconnection sites and strong shock structures. In the future, it isexpected that researchers will better understand the acceleration mechanisms for these high energy particles.
Propagation of structures through interplanetary space
When CMEs are observed near the Sun, it is unknown
whether they will encounter the Earth or not. If they are suspected to encounter the Earth, the exact time of arrival andintensity of the CME and the pile up of material in front of
it are unknown until these structures are measured by satellites located approximately 250 Earth Radii upstream of the
Earth. CMEs typically take 24-72 hours to arrive at the Earth.
Figure 8.6 shows an example of a 3-D simulation of a CME
encountering the Earth.
The propagation of the CME through interplanetary spaceis crucial in determining how much of an effect it will have on
the Earth system. If it is a fast CME moving through a slow
medium, there will be a huge pile-up in front of it, and thispile-up may cause as much of an effect as the CME itself. In
addition, the slow medium will cause the CME to slow down,
and it will take longer to reach the Earth.
Sophisticated models of the heliosphere and propagationof CMEs through the heliosphere are really in their infancy.
Since the propagation is so important in determining when
the CME will arrive and how strong it will be, significant resources are being put towards the improvement of these models.

Figure 8.5: The CME event of April 7th, 1997. It produceda ”halo event” in which the entire Sun appeared to be surrounded by the CME. Halo events are produced by CMEs
that are directed toward (or away from) the Earth. As theyloom larger and larger they appear to envelope the Sun itself.
Solar energetic particles
Starting in 1942, Geiger counters and other detectors set
up to monitor cosmic rays have occasionally seen sudden increases in the intensity of the radiation associated with outbursts on the Sun, mostly with visible flares [Gopalswamy
et al., 2002]. The cosmic ray intensity returns to normal
within minutes or hours as the acceleration process ends, andas accelerated ions disperse throughout interplanetary space[Aschwanden, 2002].
In many events, the Sun emits enormous numbers of lowerenergy ions with no more than tens of Mev (=millions electron volts). The Earth’s magnetic field diverts them to thevicinity of the magnetic poles where they may temporarily
smother the ionosphere and interfere with radio communications. Such ”polar cap blackouts” used to bother US militaryradar installations, which scanned the polar cap for hostile
missiles.
Should we be concerned about solar energetic radiation?
On Earth, we are safe, protected by the thick layer of our atmosphere, equivalent to 10 meters (32 feet) of water or about
4 meters of concrete. Astronauts on a space station orbitingnear the Earth’s equator are protected by the Earth’s magnetic field but not enough for some solar particle event. In
those cases, they are required to return to their spacecraft.
Thus, predicting these events is important to astronauts working outside their space vehicles. Also, astronauts on their way
to Mars, separated from space by just a thin metal shell, arequite vulnerable. Luckily, life threatening radiation events are
rare, especially during low years of the sunspot cycle. Still,as the large particle events of August 1972 have shown, somedanger remains even then.

8.2.4

Ground-based Measurements

More observatories
In order to examine the global structure of the thermospheric, ionospheric, and magnetospheric dynamics, it is crucial to have a wide variety of data sources covering as muchof the globe as possible. IAGA research covers a huge regionof space, but has an extremely small number of data sources.
It is surprising that any progress can be made at all. At any
given time, there are less than 200 magnetometers running.
This means that each magnetometer, on average, has to cover
2.55 million km2 . What it really means is that some regions
have relatively poor coverage, and other regions have awful
coverage. One of the worst parts is that the coverage is notbased on economy of the country at all. So, for example,
the United States has very poor data coverage considering theamount of money that is spent each year on research.
In order for progress to be made at any pace above what
is being done today, more observatories are needed. Whilesome researchers understand this and are proposing for chainsof observatories, there are not enough. In addition, the funding agencies have to realize that ground-based observatories
are very inexpensive ways to help scientists better understandour environment.
83

ionosphere system must be accomplished. This will most
likely be achieved by:

t = 69.0 hours
-3

n cm
140.0
130.8
121.7
112.5
103.3
94.2
85.0
75.8
66.7
57.5
48.3
39.2
30.0

100

Z [Rs]

50• Use of coupled models of the magnetospheric systems.
A number of groups are coupling large-scale magnetohydrodynamic models of the magnetosphere with particle codes which model the inner magnetosphere andthermosphere-ionosphere models. These coupled models will allow researchers to accurately model the complete magnetospheric-ionospheric system and carry out
numerical experiments within this system to develop amuch better understanding of how the near-Earth spaceenvironment reacts to different interplanetary medium.

0

-50

100

150

200

Y [Rs]

250• Combining magnetospheric data with global models to
put the data into context. While a number of researchersattempt to do this, it is typically in a model validation
type of study. In the next few years, it is expected that
more data analysts will turn to modelers to put measurements into context. This combination of model and data
will help to determine the first order effects as well as
showing how any subgrid-scale phenomena effect thestructure of the whole system. There is a lot of work
to be done in this area, but it is one of the most crucial
areas of research today.

300

Figure 8.6: This plot shows the distortion of a CME whichstarted as a tear-drop shape near the Sun. The line traces are
the magnetic field lines of the Sun. Here it is close to 1 AU,
and it has been significantly slowed in the solar current sheet.
Above and below the current sheet, the CME is moving faster,so the shape is distorted. This figure is from a global 3-D
simuation.

• More measurements. The magnetosphere and ionosphere are data poor. The community must be more vocal in setting up new instrumentation and getting newsatellites launched. Microsatellite technology applied
tens to hundreds of times is needed to cover as muchof the magnetospheric system as possible. In addition,using innovative remote-sensing systems, such as thoseon the IMAGE satellite, can help to examine many magnetospheric phenomena at once and in a larger context.

Creation of centralized databases
One of the main difficulties in conducting large-scale orglobal studies in the magnetospheric and ionospheric domain
is the lack of a consistent and centralized database. In orderto carry out this type of research, which is truly the future ofgeophysics, databases must either be cross-linked, or centralized. Data formats must be created which allow users to easily process and examine the data. All data providers (or thecentralized data storage facility) must buy into the specificformat(s), to allow users to use data from multiple chains.
Without these capabilities, advancement in geophysics is going to come at a slow pace. A number of researchers areworking on these problems and hopefully progress will bemade in this area.

Most of these improvements can be made because of theincrease in computing power over the past 30 years, as well
as new technology. Space science will continue to use these
new tools to make discoveries.

8.4 Conclusions
It is an exciting time to be a part of IAGA. Many of the basic
properties of the system seem to be well understood. This hascreated the demand for predictive models of the system - taking the physics and turning it into engineering. Also, because
many of the basic properties are understood, we now have theability to study the non-linear and cross-scale coupling that isthought to make the system so dynamic and interesting.

8.3 Recommendations for the IAGA
In order to accurately predict the near-Earth space environment with more than a one hour lead time, a better understanding of the solar environment must be accomplished. The
prediction capabilities can be extended up to approximately 3days if better models of the interplanetary medium are created and more accurate specification of coronal mass ejections and other large-scale phenomena near the solar surface
are accomplished.
In addition to improving the lead-time of the interplanetary conditions, a better understanding of the magnetosphere-

8.5 Acknowledgments
The author would like to thank those who responded to thesurvey which was conducted in the summer of 2002. I would
84

also like to thank Mike Liemohn, Janet Kozyra, Laura Peticolis, and Ilia Roussev for their helpful discussions on the futureof IAGA and reading this document.

Dungey, J.W., Interplanetary magnetic field and the auroralzones, Phys. Rev. Lett., 93, 47, 1961.
Dzhalilov, N. S., J. Staude, and V. N. Oraevsky, Eigenoscillations of the differentially rotating Sun. I. 22-year, 4000year, and quasi-biennial modes, Astron. Astrophys., 384,
282, 2002.

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88

Chapter 9Interdisciplinary Research
S. Adlen

9.1 Introduction

1. Committe for Mathematical Geophysics (CMG)

The mandate of the IUGG is the international coordination ofstudies of the Earth, its environment in space and analogous
problems associated with other planets. Whilst the IUGG isnominally composed of seven, semi-autonomous bodies, by
nature of the fact that the separate Associations study subsystems of an over-riding planetary system, interdisciplinary
research is essential.
The IUGG supports interdisciplinary research in two ways.
Firstly, through the establishment of joint working groups andsecondly, through the formation of commissions.
Two or more International Associations may set up andsupport joint working groups to address specific scientifictopics. During the lifetime of the IUGG, several importantinterdisciplinary collaborations have already been overseenwith significant success, e.g.,

2. Study of the Earth’s Deep Interior (SEDI)
3. Geophysical Risk and Sustainability (GeoRisk)
The world today is markedly different from that of fifty
years ago and is continually changing. A flexible framework in which interdisciplinary collaborations can be developed and disbanded as required, is needed. The real strengthof the IUGG lies in its constituent associations, which together cover the full spectrum of international geodesy andgeophysics and hence provide the requisite framework.
Within the remit of the IUGG, there are currently many
opportunities for interdisciplinary collaborations. These opportunities fall into two main categories. There are bothover arching opportunities in which all member Associations
might contribute and more specialised fields which will be ofinterest to smaller groupings of Associations.
This chapter seeks to outline some of the major opportunities for inter-disciplinary research in the fields of geodesy
and geophysics and to highlight potential roles for the IUGG
in the realisation of these collaborative ventures.

1. The International Geophysical Year (1957-58)
2. The Upper Mantle Project (1964-70)
3. The Geodynamics Project (1972-79)
4. The Global Atmospheric Research Programme(1970-80)

9.2 Over arching Opportunities forInter-disciplinary Research

5. The International Lithosphere Programme (1981-90)
At the current time, there are several working groups in existence looking to further progress in geodesy and geophysics.
Another major achievement has been the creation, throughthe International Council of Science (ICS), of the World Data
Center System.
Commissions are the second way in which the IUGG promotes interdisciplinary research. These are established by
the IUGG to serve the Union and the international geophysical community by promoting the study of particular interdisciplinary problems and tend to be of a more permanent
nature. These bodies are chartered by the IUGG Executive
Committee to conduct inter-association science. Three InterAssociation Commissions are active at the moment:

9.2.1

Planetary Exploration

Comparative planetology and planetary exploration present
the ultimate challenge as regards a problem that incorporates
the full spectrum of geoscientific disciplines. The benefits ofundertaking the challenges that are posed in pursuing theseareas of research are largely two fold.
1. Comparative Planetology and the Protection of ourPlanet: The study of planetary geologies, atmospheres
and other characteristics is important in our understanding of the evolution of the Earth and the basis of life on89

9.2.3

Earth. By studying planets and other large bodies in thesolar system, we learn about the history and possible future of our own. In exploring our solar system, we widen
our perspectives and gain a better understanding of themechanics of worlds in general, making us better able
to protect our planet’s fragile biosphere. Comparative
planetology allows us to use other planets as full scalelaboratories to improve our theories. As we move to atime in which Earth system modeling is becoming increasingly important, having the opportunity to test theories in other full-scale laboratories will be invaluable.

All of the geoscientific disciplines require observations as abuilding block for their research. Combining these observations in the most thorough and efficient way is essential.
Questions of both spatial and temporal resolution need to beresolved as each of the geoscientific disciplines seeks to improve their models to smaller and smaller scales.
Recently the problem of coordinated, integrated global observing systems has been addressed by the United Nations.
Three inter-related global systems to observe the environmentof the planet are being organized by United Nations organisations in co-operation with the scientific community and national governments.

2. Widening the intellectual, physical and technologicalboundaries of Mankind: Exploration of other planets
will push the technological capabilities of the humanrace and in doing so, will also expand our physicalboundaries and understanding of the universe.

1. Global Climate Observing System (GCOS): GCOS is
responsible for planning the collection of data on longterm climate change.
2. Global Ocean Observing System (GOOS): GOOS is implementing operational observation programmes for theoceans and coastal areas.

The Role of the IUGGThe IUGG is in a strong position to promote planetary research as it represents all geoscientific disciplines. The IUGG
might consider the creation of a new association. An association which could better coordinate planetary exploration andmodeling would be invaluable.

9.2.2

Observing Systems

3. Global Terrestrial Observing System (GTOS): GTOS isdeveloping and networking observations of long-termchange of the land and its resources.
An Integrated Global Observing Strategy (IGOS) is also
being developed to improve coherence and joint planning for
global observations of the environment. Whilst the above systems represent significant progress, observing systems thatmonitor the whole Earth system also need to account for therequirements of other geoscientific disciplines. Some examples of this are given below.

Mathematical Techniques

The geosciences provide an impressive array of important
problems that command the attention of applied mathematics. They also offer a need, on top of an intellectual desire,to advance the foundations and techniques of applied mathematics to meet their challenges.
Methods in continuous and discrete dynamical systems,
stochastic processes, homogenization, ergodic theory, renormalization, inverse problems and the quantification of uncertainty are all required. Some recent developments that
require numerical and theoretical modeling tools are largescale compressible jets (IAVCEI, IAGA), time series analysis and stochastic modeling of catastrophic events (IAVCEI)
and tools, such as adaptive gridding techniques, to allow theincorporation of processes on disparate spatial and temporalscales into increasingly comprehensive models (IAMAS).

1. The Thermosphere requires improved monitoring.
2. Hydrologists require observations at a much higher spatial resolution than scientists concerned with climatechange or the environment.
3. The whole of the Earth system is underpinned by accurate physical geodesy, which requires observations atincreasingly higher spatial and temporal resolutions.
All desired observation goals and data products could easily
be attained with a well-constructed global observing system.
Some progress is already being made in using data from specific observing systems across a range of geoscientific disciplines (section 9.3.2). Both NASA’s Earth Science Enterpriseand ESA’s Living Planet program are also significant steps
toward reaching this goal NASA [1999]; ESA [1998].

The Role of the IUGGThe Committee on Mathematical Geophysics is an interassociation committee of the IUGG, which already satisfies
the need for co-ordination of research in the mathematicalfields associated with the geosciences. The committee organizes bi-yearly conferences, and its continued presence is invaluable to the whole of the geosciences.

The Role of the IUGGThe ICS is involved with the three observing projects described above hence already representing the IUGG to some90

extent. The IUGG should, however, ensure that the ICS isaware of its requirements as regards the data products returned from a global observing system that might benefit disciplines across the whole range of the geosciences. Whilstmuch political emphasis is placed upon the monitoring of theclimate and environment, the needs of other scientific disciplines should not be neglected at its expense. Once a truly
global observing system is in place then returning all of thedata products needed for all realms of geoscientific research
will be easily realisable. The IUGG should be proactive inthe sponsorship of this goal.

9.2.4

temporal scales into a comprehensive Earth system model
is non-trivial and demands input and co-operation across thewhole range of the geosciences. This a growing field which
will produce invaluable results to society over the coming
years.
The Role of the IUGG
Each of the geoscientific disciplines feeds directly into an integrated Earth system model. The IUGG is in a strong position to coordinate Earth system modeling projects. Whilst
the IGBP has already been established by the ICS, the IUGG
could still promote the coupling of models for elements of the
Earth system within the realm of the IUGG. Linking models of subsystems together one by one is an important process. The difficulties involved in trying to reconcile models
that are based upon different spatial and temporal scales areenormous. If all of the subsystems represented within the
IUGG could be coupled together then this would represent
enormous progress and is something that the IUGG is in aposition to actively encourage.

Communication and the Availability ofData

The past decade has seen an explosion in information technology and a revolution in global communications. A major achievement has been the creation, through the ICS, ofthe World Data Center System, from which the data gathered
during several major programmes are available to research
workers everywhere.
The above type of undertaking is vital. All research requires data and the sharing and availability of data is thus
essential. In the modern age of global communications, thisshould be relatively easy to achieve and would result in hugebenefits to the scientific community.

9.2.6

It is vital that the geosciences maintain a view a of future withthe continual re-assessment of goals and milestones. Undertaking projects that push our intellectual and engineering capabilities to their limits are important in the advancement ofresearch. Projects such as the development and maintenanceof new habitable environments and the intentional forcing ofsystems to mitigate hazards could be established to the benefit
of both society and research. Through this type of undertaking enormous progress is often made in more routine areas ofresearch. Aim for the stars, reach the sky!

The Role of the IUGGThe IUGG should advocate, and be active in promoting, freeaccess to all data sets. The IUGG is also in a strong position
to ensure that data is additionally made readily available toresearchers in developing countries.

9.2.5

Looking to the FutureHigh Resolution Earth System Modeling

The Role of the IUGGThe ultimate challenge of Earth system science is to consolidate the scientific findings from different disciplines into an
integrated representation of the coupled atmosphere, ocean,ice, land and biosphere system. It has become clear thatmodels need to progress to higher resolutions in order to adequately represent processes taking place.
The Global Analysis, Integration and Modeling Task Force(GAIM) is a component of the International Geosphere Biosphere Program (IGBP) of the ICS. The goal of GAIM is toadvance the study of the coupled dynamics of the Earth system, using as tools both data and models. This is just one
example of a number of such projects throughout the world.
A further development in Earth system modeling comesfrom projects such as “The Earth Simulator Project” in Japan.
This project creates a ”virtual earth” on a supercomputer toshow what the world will look like in the future by meansof advanced numerical simulation technology. The reconciliation of processes occurring on vastly different spatial and

The IUGG general assembly every four years provides an excellent platform for reflection and re-assessment. The sponsorship of working groups such as “Geosciences: The Future” and attaining ideas of young scientists is an excellent
idea. Through the promotion and co-ordination of forward
thinking and far-reaching research ideas, the IUGG can be ofhuge value to the geoscience community.

9.3 Other Opportunities for Interdisciplinary Collaborations
In addition to the opportunities for interdisciplinary researchwhich encompass all fields of geoscientific research, there aremany chances for research between a smaller number of theassociations of IUGG. Some of the potential opportunities,
91which are currently being, or could be exploited, are presented below.

9.3.1

Improving and coordinating these investigations so as to be
more strongly linked with the over-riding goal of understanding the hydrologic cycle would be beneficial. There is scope
for the IUGG to endorse these studies through the development of a structured programme of research.

The Hydrologic Cycle (IAMAS, IAPSO
and IAHS)

The International Association of the Physical Sciences of the
Oceans (IAPSO), the International Association of Hydrologic
Sciences (IAHS) and the International Association of Meteorology and Atmospheric Sciences (IAMAS) have the chance
to work collaboratively to understand the dynamics and interaction between ocean, atmosphere, surface and groundwater,which are closely linked via the hydrologic cycle. This isa difficult task that involves the reconciliation of models on
vastly different spatial and temporal scales. The task is, however, crucial to the maintenance of water supplies and hencelife on Earth.
During the IUGG general assembly in Sapporo, several interdisciplinary undertakings are already being investigated related to the hydrologic cycle.

9.3.2

The Role of Geodetic Sensing in Interdisciplinary Earth Science (IAG and Others)

Classically, mapping has been viewed as the main purposeof geodesy. However, by establishing reference geodetic networks, geodesy has become fundamental in the performanceof other disciplines, whose activities are related to positioning, such as urban and environmental management, engineering projects, (international and national) boundary demarcation, ecology, geography, hydrography, etc. Many applications are also found in other scientific fields, e.g., theoretical and exploratory geophysics, geodynamics, space science,
astronomy, oceanography, atmospheric science and geology.
New techniques to observe and to analyse the Earth as a complete system have made the relationships between disciplines
stronger. Accordingly, some interdisciplinary enterprises thatutilise or could utilise geodetic information are highlighted
below.

1. The Decadal to Centennial Variability of the Ocean
and Atmosphere (IAPSO, IAMAS, CLIVAR)
2. The Surface Ocean-Lower Atmosphere Study (IAMAS, [ICACGP,ICPM], IAPSO)
3. New Perspectives of Coupled Tropical OceanAtmosphere Dynamics and Predictability (IAPSO,IAMAS, CLIVAR)

1. The Hydrological Cycle ( IAG, IAMAS, IAPSO,
IAHS, IASPEI) Geodesy can provide precise information about melting (glaciers and polar icecaps), sea levelchange, atmospheric mass movements, ground waterand soil moisture.

4. Arctic Environment Change (IAMAS, IAPSO,
IAHS)
5. Groundwater Inputs to the Ocean (IAPSO, IAHS)

2. Precise modeling of crustal deformation, including
plate tectonics, volcanoes and earthquakes (IAG,
IAVCEI, IASPEI) Geodesy can precisely monitor
crustal deformation (secular and episodic, extended andlocal), as well as gravity and Earth’s rotation changes
due to mass displacements. The deformation of surface
topography reflects the dynamical processes that are occurring in the Earth. Continuous geodetic observationsof surface deformation provide not only useful information for understanding the dynamics of the Earth’s
interior, but also indispensable information on the occurrence of earthquakes and volcanic eruptions. Most
volcanic activities are accompanied by seismic activity.
Revealing processes of interaction between earthquakes
and volcanic activities would be a clue to better understanding the triggering effects between eruptions andearthquakes. To obtain detailed images of the seismic
structure of volcanoes, enhanced seismic observations
in volcanic areas as well as the advancement of theories
and techniques of seismic wave propagation and modeling are essential.

6. Snow Processes: Representation in Atmospheric andHydrological Models (IAHS/ICSI, IAMAS)
7. Water and
MAS,IAHS)

EnergyBudgetWorkshop(IA-

8. Measurement and Distribution of Precipitation (IAMAS, [IPCC, ICPM], IAHS)
9. Worldwide Sea Level Change (IAPSO, IAG)
10. The Treatment of Precipitation in Cloud and Climate
Models (IAMAS, [ICCP, ICCI],IAHS)
11. Land Ocean Atmosphere Interaction in the Coastal
Zone (IAMAS, IAPSO, IAHS)
12. Global Sea Level Rise, Global Climate Change andPolar Ice Sheet Stability (IAMAS, [ICDM, ICCI,ICPM], IAPSO, IAG, IAHS)
13. Physical Aspects of Air-Sea Interaction (IAPSO, IAMAS)
92

3. Atmospheric Modeling (IAG, IAGA, IAMAS)
Geodesy can provide valuable information about pressure and humidity from atmospheric sounding usingGPS.

included in any full Earth System Model. The IUGG is already aiding this area of research through several joint symposia at the general assembly and continued support from theIUGG is required. The working group on Long-term Trends
in the Mesosphere, Thermosphere and Ionosphere alreadygoes some way to supporting this field of research.

4. Coupling Between Atmosphere, Ocean and Solid
Earth (IAMAS, IAPSO, IAG) How do the solid Earth,atmosphere and ocean interact with each other? How do
the atmosphere and ocean shake the solid Earth? Does
the melting of polar ice caps due to global warming induce the deformation of the surface topography?

9.3.4

The emission of SO2 from volcanic eruptions provides an
excellent opportunity for atmospheric scientists to study the
response of the atmosphere to a point-like forcing and for vulcanologists to investigate the processes through which thesevolatiles are released into the atmosphere. The study of these
events requires significant collaboration, particularly in termsof chemical modeling, prediction and observing systems. A
joint symposium has been arranged by the IUGG to bring together expertise from both fields with aim of tackling thisproblem. This initial step should be built upon to the longterm benefit of both associations.

The development of a systematic Earth model integrating a variety of Earth processes, such as global warming,
growth and regression of polar ice caps, plate tectonics,
continental evolution, etc, which fully incorporate thephysics and chemistry of the processes considering thesignificant differences in time-scale, is a common goalof geosciences. This is a piece in the overall goal of acomplete Earth system model (section 9.2.5).
It is important that as much information as possible is extracted from geodetic observations. Whilst this highlights thefact that not enough information is currently extracted fromavailable observations, it is, however, just a small issue in theultimate goal of achieving a global observing system (section
9.2.3). Sessions on “Interdisciplinary Science from Improved
Earth System Modeling” and “Interdisciplinary Science from
Remote Sensing” in Sapporo are positive steps toward addressing this problem. The IUGG will continue to play animportant role in addressing both the issue of efficient data
usage and the implementation of a truly global observing system.

9.3.3

Climate Response to SO2 Aerosol Forcing (IAVCEI, IAMAS)

9.3.5

Generation and Propagation of Tsunami(IASPEI, IAPSO)

Earthquakes in oceanic regions sometimes generate hugetidal waves, “tsunami,” which bring catastrophic damage incoastal areas. The scientific investigation of their generationand propagation is central to the creation of a practical warning system to mitigate tsunami disasters. The commission on
Tsunami is already active in advancing research in this field.

9.3.6

The Interaction of the Thermosphere,
Upper Atmosphere and Solar Forcing(IAGA and IAMAS)

Seismology for the Earth and the Sun(IASPEI, IAGA)

The studies of free oscillations of the Earth and the Sun sharessome common theoretical grounds. The development of seismology would complement helioseismology, and vice versa.

The link between phenomena in the Upper Atmosphere andThermosphere and the additional role that solar forcing plays
in both is an active area of research between the associationsof IAGA and IAMAS.
The mesosphere-thermosphere-ionosphere (MTI) system
is affected by long-term changes and trends in such things
as atmospheric concentration of greenhouse gases, geomagnetic activity and solar activity. The phenomenology of theequatorial ionosphere-thermosphere system is controlled particularly strongly by vertical coupling to lower atmosphericlayers. Understanding the coupling between these systems isessential. An additional connection between the associationsof IAGA and IAMAS is the fact that climate change could
partially be of solar origin.
The relation between the Upper Atmosphere, Thermosphere and solar forcing is an important aspect that must be

9.3.7

Water, Earthquakes and Volcanoes(IAHS, IASPEI, IAVCEI)The process of groundwater transportation and its implications to the precursory anomalies of earthquakes need to beevaluated quantitatively. Fluids in the crust may play a crucialrole in earthquake and volcanic dynamics.
It has long been known that fluid injection can generate seismicity. In addition, within the last decade, it has
been discovered that seismic waves can trigger earthquakes
in geothermal areas and many explanations involving mobile,
hot fluids have been proposed. Fluids are also often invoked
to explain the low friction on faults and other dynamical features of fault rupture.
93

Bibliography

Now that solid Earth geophysicists have posed these questions about the role of crustal fluids, they need to answer the
problems using the knowledge-base of the hydrological sciences. Ground-water monitoring could constrain the mechanisms for long-range triggering and changes in water chemistry and temperature may constrain the degassing history ofshallow magma bodies. The dynamic role of water duringrupture can, however, only be quantified if we also understand the groundwater flow in the vicinity of the fault bothduring and in between earthquakes. Many of these questions
will also push the boundaries of hydrology.

9.3.8

ESA, , The science and research elements of ESA’s living
planet programme, Technical report, ESA, 1998.
NASA, , EOS reference handbook, Technical report, NASA,
1999.
Oki, T., The global water cycle, In Browning, K., and R. Gurney, editors, Global Energy and Water Cycles. Cambridge
University Press, 1999, pp.10-27.

Interactions with Disciplines Outside
Geoscience

In addition to the potential for collaborations within the geosciences, there are also many opportunities for interactions
with disciplines from outside the realm of the geosciences.
1. Social and Political Sciences In association with the social and political sciences, questions such as how thegeosciences might best serve society should receive attention. For example, issues of early warning systems,
sustainable development and the support of science must
dealt with.
2. Biological Sciences As Earth system modeling becomesincreasingly important, so the understanding of the interaction of biological systems with the geo-environment
becomes essential. Quantitative understanding of biological exchange processes, for example in the carbon
cycle, is a significant unknown in Earth system models.
3. Engineering Sciences The relationship between engineering science and the geosciences occurs on two levels. From a positive viewpoint, engineering science provides the capacity for improved resilience to geo-forces.
On the other hand, engineering projects can have a detrimental effect on geo-systems, e.g., pumping that causes
subsidence. The relationship between the engineeringand geosciences should be strengthened in order to ensure that our engineering capabilities are used most beneficially for society.

9.4 Conclusions and Recommendations
There exist many exciting opportunities for interdisciplinary
collaborations within the geosciences. The IUGG is alreadyassisting in the promotion of several of these opportunities
with other worthwhile cases available which would benefit
from the support of the IUGG in the future.
94

Chapter 10

Societal Impact
K. Yoshizawa

10.2 Geophysical Risks: Prevention of
Natural Hazards

10.1 Introduction

The uniqueness of the Earth compared to other terrestrial
planets is its dynamic activity in a variety of forms, i.e., global
circulation of the atmosphere and oceans, plate movement,
volcanic activities and earthquakes, which sometimes cause
devastating damage to our society. Society is affected both
economically and socially by the impact of such natural hazards. Even if our life standard has been improved by virtueof technological development, there seems no practical way
to keep away from such disasters. Although we are always
going to be at risk from geohazards, it is certainly possible tolimit the damage they cause. Anything that can be done inthis respect is very worthwhile.

The Earth provides us with a number of benefits, such as natural resources and an inhabitable climate, which help to enrich
human life. However, it sometimes can harm us with natural
disasters and severe weather. Sustainability of human society
depends strongly on the environment, and thus the development of geosciences is critical for a better understanding of
our living environment, and its sustainable development.
Scientific results, particularly those related to natural hazards and the human environment, should be transferred properly to society, decision and policy makers, and the public,
addressing issues and providing guidance in response to specific societal needs.

10.2.1

Action-oriented recommendations from the geoscientificcommunity can be used to evaluate, formulate and create aplan of both national and international policies for sustainable development of our society. Such an effort will be crucial
for the communities of geosciences to strengthen their credibility, which will be helpful in enhancing the possibilities
of gaining better financial support for further development ofgeosciences. It is also an important role of international scientific communities to make efforts to reinforce the capacity ofdeveloping countries to deal with environmental, social andeconomic issues.

Interactions Between Community andGeosciences

Close Linkage with Decision Makers: Scientific progress
will not mitigate hazards unless results are transferred
effectively to local decision makers during a crisis.
Usual practices in communication are inevitable for bothscientists and decision makers to take prompt actions
against geohazards. In order to make the most of thelatest results of geosciences, it is essential to establish ameans of interactive communications between decision
makers, public and geoscientists. All important information must be passed to the public in a common languagethat can be understood by anybody. Only with such efforts can the latest results of geosciences be a useful
guide for the public. Through communication with policy makers, society becomes aware of the potential risks
and can account for them in terms of adequate insurance
coverage and defense against the potential hazards.

IUGG stands in an important position for promoting scientific studies of the Earth and its environment and for communicating with the international society. Therefore, the IUGG
can be an ideal facilitator to link the people’s interests andstate-of-the-art geoscientific researches. In this chapter, we
discuss some important aspects of the relationship between
society and geosciences, and what geoscientists can do forthe benefit of human beings living on this planet.

Efficient Use of Hazard Maps: To evaluate potential risksof geohazards, hazard maps based on geological andgeophysical researches are of great help for employing
95

countermeasures against natural disasters. Also, it canbe useful for creating practical manuals in case of an
emergency, for the establishment of insurance policies,
and for future land use. This type of information is particularly useful for avoiding devastating disasters thatare still difficult to predict precisely, such as volcanic
eruptions, earthquakes and tsunami.

earthquakes, are rather difficult to predict, since the direct monitoring of the Earth’s interior is impossible. By
improving models of the system with which the risk
is associated, and enhancing monitoring system, predictability can be improved, thus allowing society to bebetter prepared when the hazard strikes.
Simulating Geohazards: It will be helpful to utilise new
powerful computing facilities, which enable us to simulate the effects of natural hazards with high degree of
accuracy. Especially, for some gigantic disasters withdifficulty in their predictions, such as earthquakes, thisapproach should be helpful to quantitatively assess possible damages. The results of numerical simulations canbe a useful guide for taking precautions and countermeasures against devastating natural disasters.

Employing Early Warning Systems: With extensive observation systems, it is now possible to transmit an emergent warning to the public immediately after a natural
hazard has occurred. For example, in the case of large
earthquakes, an automatic shutoff system for gas lines
is important to prevent subsequent fires. Particularly formega-cities with growing populations, establishment ofan early warning system is essential to mitigate the damages of geohazards.

10.2.210.2.3

Effective Use of Technology and Scientific Results

Some Counter-measures Against Gigantic Natural Hazards

Societal impact of some typical natural disasters are summarised below, along with raising some plausible countermeasures against these hazards.

Comprehensive Observation for Hazard Mitigation:
Continuous monitoring of the Earth is one of the mostessential factors to mitigate natural disasters. Observation with satellites provides us with many useful
information about the current state of the Earth at bothglobal and regional scales, for example, monitoringrain falls, sea level rise, variation of gravity fields andso on. GPS observation provides us with informationon the crustal deformation, which may lead to fault
rupture or volcanic eruptions. Continuous geodetic
observations of crustal deformation may enable us tolocate possible earthquake sources. The measurementsof the gravity fields can be helpful in detecting mass
movements in the Earth, e.g., movement of a magma
chamber beneath volcanic areas, which may lead to an
immediate eruption.

Extreme Weather Events: Extreme weather events aresome of the planet’s most devastating natural disasters.
There are many forms of meteorological phenomena at
a variety of scales of both time and space, which sometimes bring devastating damage to society, e.g., typhoon,
hurricane, tornado, downfall, flood, drought and so on.
Progress in the study of the atmospheric interactions thatshape weather phenomena has created an opportunity tomake major advances that have led directly to improved
weather warnings and predictions. This gives communities a greater confidence, an improved chance of minimising the effects of extreme weather events, and hence
a superior quality of life. New atmospheric models havethe capability to run at horizontal resolutions of around
1km or less, with the increasing power of computational
facilities, and open up the possibility of significantly improving predictions of severe weather. Elucidating relationships between extreme events and modes of climate
variability, such as El Nino, will also be vital.

Information Technology: In case of devastating natural disasters, such as earthquakes and tsunamis, efficient andstable ways to transmit the situation in a disaster area
are indispensable for taking prompt actions against thehazards. It will be useful to create a system utilising information technology as a communication tool in caseof emergency. Outer space monitoring for disasters anddamages may be helpful in the immediate transmissionof rescue information.

Volcanic Activity: Most of volcanic activities are accompanied by some precursors, which can be observed in most
volcanoes as sudden increases of seismic activity and/or
crustal deformation. These events are likely to be related
to active movements of magma chambers beneath volcanoes, which can be associated with subsequent eruptions.

Improve Predictability: The current situation of the predictability of natural hazards depends significantly on
the type of natural phenomena, e.g., the occurrence ofsevere weather can be well observed and predictablethrough comprehensive means of monitoring the stateof the atmosphere and hydrosphere, whereas disasters
rooted in the geosphere, such as volcanic eruptions andPrediction for volcanic eruptions seems more plausible compared to that for earthquakes. In fact, there
have been successful examples for predicting eruptions,which saved a number of lives (e.g., an eruption of Mt.
96

10.3 Human Life and Environment

Usu in Hokkaido, Japan in 2000). However, these successful predictions seem to be rather empirical, and thelong-term experience of observers is required for making decisions about warning society prior to the eruptions. More quantitative methods for evaluating the stateof magma chambers underground will be inevitable.
Continuous and massive monitoring of volcanoes withhigh potential risks of eruption should be essential.

For improving the quality of life for human beings, a better
understanding of the Earth system is invaluable. Continued
studies of geosciences will be essential to keep the continuousand sustainable development of modern society and to keep abalance between human welfare and the natural environment.

10.3.1

Earthquakes: Preparing for catastrophic earthquakes is a
critical issue for large cities with high seismic activity. Practical ways to predict earthquakes are not yet
available. However, it is invaluable to take precautions
against disastrous damages that may be caused by large
earthquakes.

Global warming is one of the critical issues for modern society. Continuous temperature rise of the atmosphere will cause
melting of polar ice caps, resulting in the sea-level rise, which
will threaten most metropolitan cities near coastlines all over
the world. For some countries in the southern Pacific islands,
the effect of the sea-level rise is a vital issue, which threatens
the existence of their home lands. The cause of the averagetemperature rise can be attributed to human activities, especially the rapid industrial developments throughout the 20th
century. Still, it is important to separate the effects of humanactivity from natural global changes, so that we can quantitatively evaluate the limitation of industrialisation. As certaintyof the causes for climate change improves, the thresholds oftolerable risks due to projected climate change need to be defined, and the communication of scientific results to both society and policy makers needs to be improved.

In order to prevent hazardous disasters in urban areas,
especially such as mega-cities with high population densities, it is vital to quantitatively evaluate potential seismic risks, utilising hazard maps based on geological andgeophysical investigations of active faults and local underground structure in conjunction with numerical simulations of strong ground motion. Basic researches on
crustal deformations and seismicity pattern analysis arealso essential.
From the view point of societal benefit, the legislationof appropriate building codes is vital in areas with highpotential risks. It is also important to utilise real-time information on strong ground motions for controlling large
structures in order to minimize the impact of large earthquakes on metropolitan areas.

Anthropogenic Effects: Global climate change has attained
the enormous interest of the public due to its potential toeffect human activities and the environment. A criticalissue is to understand the possible anthropogenic role inclimate change. Human-induced changes in climate, observed on decadal time scales, are already evident. Atmospheric pollution now hangs over many regions of theNorthern Hemisphere. The thinning of the stratosphericozone layer, most notably over Antarctica, is a humancaused feature of the planet. The greenhouse gases being added to the atmosphere will reside there for decades
to centuries and are predicted to increase average global
surface temperatures by several degrees, a change that islarger than the natural variation occurring over the past
15,000 years. The separation of natural climate change
from that caused by the activities of humans needs to beestablished.

Tsunami: Some earthquake sources in the ocean bottom andland slides near coastal areas occasionally cause large
tidal waves, tsunamis, which hit coastal inhabited areas, bringing catastrophic damages to cities facing theoceans. In case of shallow earthquakes in the ocean bottom, the generation of tsunamis can be expected. Thus,
the immediate determination of an earthquake source
helps for early warning of tsunamis, which gives communities great confidence, minimising the damages oftsunamis. With detailed information on bathymetry, it
is possible to simulate propagation of tsunami waves,which helps to create tsunami hazard maps. Construction of breakwater based on this information is essential
for preventing hazardous tsunami disasters.

10.2.4Global Change and Human Activity

Observation System: Satellite altimetry enables scientists
to forecast El Nino, whose influence on the global climate as well as on agriculture, agronomy and hydrology,
is enormous. The sea level changes, measured also withsatellite altimetry, are a response to global warming. The
influence of the global climate changes on ice sheets canalso be observed in a similar way. All of these aspects
form an accurate and reliable tool for assessing the current climate and for predicting future climate changes in

The Role of the IUGG

In 2000, IUGG launched the Commission on GeophysicalRisk and Sustainability (GeoRisk Commission) for promoting scientific studies to reduce the risks of natural hazards
in the modern society. The continuation and growth of thiscommission allows the IUGG to play a significant role in the
management of georisk.
97

Infrastructure for Stable Water Supply: The infrastructures for water supply is not yet sufficient in many areas,
especially in developing countries. In order to sustain
the growing population in the world, international
cooperation and support for a stable water supply andsanitation are essential to provide fresh and clean water,
particularly in developing countries. Prediction andmanagement of water resources is of vital importancefor the sustainable development of society.

both short and long terms as well as appropriate warning
to countries and cities facing coastal areas.
Modeling Climate: Only through the development and application of a high-resolution integrated global modelingand observation system can our influence on the climate
and environment be estimated. A better understandingof sources, processes and couplings between different
parts of the climate system is required so that anthropogenic effects can be accurately and efficiently represented in models.

Transferring Scientific Achievements: Only if the scientific communities work together with policy andRole of Geoscience in Environmental Issues: The
geodecision-makers can water issues be successfully adsciences, especially atmospheric sciences, oceanogdressed. Knowledge and understanding of water issues
raphy and hydrology, are a vital component in theare essential and should be further encouraged. National
control of environmental issues, e.g., in the monitoringand international information networks on water issues,of air and water pollution and greenhouse gases. It isusing modern technologies, must be strengthened. This
important to transmit the latest information to warn
is especially crucial in many developing countries where
the public about the influences of human activities oninternational assistance needs to be enhanced. It may
environmental problems.
be helpful to formulate communication strategies thatwould allow scientists to better communicate with sociIncreased Public Awareness of Issues Affecting Our Climate:
ety disseminating their latest results. It should be vital to
One of the most important factors of geosciences is the
respond to the needs of policymakers while being firmly
communication to the general public of the effects thatbased on scientific understanding and knowledge.
humans are imposing upon our climate. As certainty incauses of climate change improves, these results must
be communicated, as a matter of urgency, to policy
10.3.3 Improvement of Quality of Life
makers.
The quality of human life can be improved by the effective
Political Aspects: Global environmental issues can partly be
use of scientific results on the Earth system. Several geoattributable to the for-profit disposition of the world’s
scientific topics that enrich our everyday life are discussed
societies. It is important to keep a balance between the
below.
preservation of the natural environment and the continuous and sustainable development of society so that we
Weather Forecasting: Reliable forecasting is becoming incan sustain growing populations, especially in the develcreasingly important to society, especially regqarding
oping countries. Precise understanding of the effects of
its effect upon energy, health and agriculture. Accuhuman influence on the environment and the communirate weather forecasting allows a greater certainty when
cation of these results to policy makers are essential.
planning ahead in weather dependent industries. It also
benefits the management of water resources and otherelementshaving a direct influence upon the sustainabil10.3.2 Management of Water
ity of both our environment and our economies. Skill in
Water is one of the most fundamental resources necessary forforecasting has improved dramatically over the last 20
all life inhabiting the Earth. In some parts of the world, theyears, and today, we enjoy considerable confidence inconstant shortage of water resources is a vital issue, which
predictions from periods of days to years.
directly threatens human life. The management of water reNear-Earth Space Environment: Satellites, which are essources is an environmental issue, which results from geosential instruments for observing the Earth, are now also
scientific researches. Atmospheric physics, hydrology andindispensable to our everyday life as communication
oceanography, have an integral role to play.
tools on the Earth. However, they cost a lot of money
Hydorological Cycle in the Earth: It is essential toto build. Satellites can be destroyed by a number of phestrengthen international cooperation for the study ofnomena, which occur in the near- Earth space environprocesses related to the Earth’s atmosphere, hydroment, such as radiation erosion of electronics, charging
sphere, biosphere and geosphere as a way to betterof space craft and subsequent arching, which may occur,
understand water resources and the movement of waterand the ejection of the space craft from the magnetic stathrough the Earth system.
bility region of space. Understanding of the near-Earth9810.4.1

space environment is quite important because of the increasing number of space assets, which incur significant
costs in their building and launching.

IUGG and its associations have been publishing educational
materials for school use. Still, most developing countries are
suffering from shortages of qualified teachers in geosciences.
Recent rapid growth of internet technology provides us withthe possibility of a world-wide education system through theinternet.
In this regard, enhancing the contents of the IUGG web site
is fundamentally important to promote the scientific activities
of IUGG, as well as to attract people’s interest in geosciences.
It is also recommended to translate the contents into somemajor languages other than English and French. It may also
be helpful to upload some educational materials on the IUGG
web site, so that people in any country can easily access them.

Precise and Reliable Reference Frame: The combinationof the physical and geometrical reference systems, together with the improvement of their components, will
support the users to achieve 1 cm level in navigation andto increase up to a few centimeters level of the real time
positioning accuracy. This will also help to build a consistent infrastructure of global spatial data under the newconcept of the ”digital Earth.”
Energy Resources and Sustainability: We have been relying mainly on fossil fuels, such as oil, coal, and naturalgas, as the major sources for creating energy, which isconsumed enormous amount everyday. Although fossil fuels have been sustaining modern society, their use
has yielded drastic changes of the Earth’s climate due tothe emission of green house gases, which leads to global
warming. Besides, there is a limitation in the storage ofsuch fossil resources in the Earth. For continuous development of the human society and, as a whole, preserving the natural environment, the quest for alternative energy sources is essential. As a possibility, wave energyof the ocean can be a clean and effective energy source.
The recommendations for the use of other clean sources,
such as solar and wind power, should also be promoted
worldwide.

10.3.4

Efficient Use of Modern Technology for
Scientific Education

10.4.2

Promoting International Schools

IUGG should also facilitate international schools of geosciences for young generations. It should be useful to openIUGG summer schools, for example, for K-12 students, undergraduate and graduate students, and for the public, inviting
lecturers from each association to foster the geosciences. In
this regard, establishing an international education centre forgeosciences may be of great help in fostering geosciences tothe next generation.

10.4.3The Role of IUGG

Communication with Society

A critical issue for the IUGG to consider in the coming
decade may be to look for better ways to convert and disseminate scientific information for societal use. One area of improvement could be a better education of the public throughmore convincing arguments about the importance and usefulness of science, especially in dealing with the assessment andmitigation of natural hazards. Television is a great tool inthis respect; therefore, more educational television programs
should be developed to address such issues. Communications
with mass media at regular intervals could also be useful for
dissemination and preservation of scientific results.

IUGG is in the most appropriate position to be a facilitator
to try to adjust the balance between development and environment, making the most of its truly international characterand expertise in geosciences. Proactive actions of IUGG for
communicating with society will be more important for sustainable development of international society in the future.

10.4 Geoscience Education and Outreach

10.4.4

Geosciences are among the most important scientific studies, which are directly related to our living environment andhave a significant impact on the modern society. For the continuous development of geosciences in the future, promoting
education at various levels is essential. In recent years, children’s incuriosity about science has been a serious concern ofmodern society. It is essential to enlighten people about thecurrent state of the Earth, and what we can speculate about
the future of our environment from the latest results of geosciences.

International Assistance to Developing
Countries

International cooperation is inevitable for bringing up young
geoscientists and promoting geoscience education and researches in developing countries. In this regard, professional
training programs for scientists from developing countries areuseful to better understand issues they face in their countries.
Appropriate scientific and technological assistance to developing countries is also vital in order to reduce damages andcasualties in these regions in case of disasters.
99

10.5 Conclusion
The role of geoscientists will become more important in the
21st century to foster people’s understanding of our planet.
Because of its truly international character, IUGG has an advantage over other large geophysical associations, which areoriented toward a particular country or region. The role of
IUGG as a facilitator to link the international society and scientific community should become more important in the coming decade for the sustainable development and the preservation of the natural environment.

10.6 Acknowledgment
The author would like to thank B. Chouet and K. Suyehiro for
their useful comments on issues of IUGG for societal benefit.

100Chapter 11

Developing Countries
L. Sánchez

Geosciences have strongly developed in the last century,
not only in observation techniques, but also in theory andmodelling. Their analyses are key in the quest towards aclearer understanding of the Earth, its natural resources andenvironment, and human interaction. However, this development has been negatively affected by its non-homogeneous
appropriation world-wide. The phenomena that are studied
by geosciences have a global character, they are present over
the whole Earth, and their variations affect also the whole
Earth, so they have to be uniformly observed over the whole
Earth. In the same way, the advancements of the new discoveries in geosciences have to be globally applied to continue
a harmonized development, always looking for the maximum
benefit to society, seen also from the whole Earth point ofview. Nowadays, it is not possible to assume geosciences as
isolated islands, they are strongly connected and their specificanalyses and complement each other. Similarly, the isolated
study of geoscientific phenomena in space and time leads tomisinterpretations that, in the end, will represent inaccuracies in the corresponding models and results. Until now, theprimary role in the performance (development, application
and benefits) of geosciences is being played by industrializedcountries; however, the state-of-the-art demands that developing countries interact directly on knowing, developing andtaking advantage of the new global character of geosciences.
According to this, the present chapter will discuss the principal aspects of the relationship between developing countries
and the geosciences covered by the International Union of
Geodesy and Geophysics (IUGG).

oping countries, and its exploitation generates strong damages in the environmental conditions. This situation places
geosciences in a strategic relationship with developing countries: Firstly, preservation and adequate exploration of theseresources require new scientific knowledge and advances intechnology to facilitate their management. Secondly, they allow enhanced environmental stewardship and make it possible to avoid or minimize potential catastrophic problems,such as famine, waste, and environmental degradation. Keeping in mind that these resources are fundamental to life worldwide, their consequences are also a world-wide responsibility.
The challenges of this century, among others, include how
to stabilise the fast-growing global population, sustain foodproduction, avail all of sufficient fresh water, minimise theimpacts of natural disasters and address environmental concerns. This requires new commitments in science and technology not only from industrialized countries, but also fromdeveloping ones. In this regard, the field of geosciences, relevant to the expertise of the IUGG, should contribute to addressing the concerns and challenges of society.

11.2 Observing data world-wide
Recent developments in science and technology, such as computers, communication and information technology, satellites
and new numerical methods, have greatly contributed to themonitoring, collection, processing and distribution of geodetic and geophysical data and products for operational and research activities. In the same way, the Earth is observed asa unique system with an extended gamma of phenomena thatare strongly correlated and obligate the use of input data in a
global scale with the convergence of all geosciences. However, the observatories to these phenomena are mainly locatedin the industrialized countries, and its poor densification indeveloping countries (the greatest part of the globe) leads toinaccurate models that create obstacles for the continued advancement of geosciences. As a consequence, it is necessary
to improve the local observing infrastructure (equipments,

11.1 Natural and energetic resources
provision
The growing population (more than six billion people) andglobal economies place enormous pressures on natural resources and environments. As a matter of fact, the energetic
and natural resources reservoirs are mainly located in devel101

procedures, modelling) in developing countries. Keeping in
mind that these countries do not have sufficient financial resources, educational features or expertise to undertake thistask, IUGG should play an orientation role, promoting international projects with technology and educational transfer, making possible the integration of geoscientists from developing countries in special working or study groups, organizing scientific meetings in these countries to advertise geosciences among them, guaranteeing free and cheap publication facilities, making data available for scientists in developing countries.

ful tools produced by geodesy and geophysics to natural disasters management, planning, sustainable development, etc.
are not known, and as a consequence, these disciplines are
neglected. In this way, the question of public awareness ofgeosciences is a very relevant and global theme for all those
who work with geodetic and geophysical research. At thispoint, the role of IUGG is fundamental in providing the public, decision makers and industry with correct information onthemes related to geosciences and its professionals. However,these questions are not restricted only to developing countries, but they also hold for the industrialized ones.

11.3 Strategic positions to analyse
concrete phenomena

11.5 Vulnerability to natural disasters
The natural and social conditions in developing countries
make them highly vulnerable to natural disasters, suchas earthquakes, flooding, volcanic eruptions, landslides,
drought, severe weather events and changes in climate, which
frequently affect the poorest parts of the population. Oneof the most important objectives of geosciences, as a consequence of IUGG, should be to supply technical tools that leadto mitigate these natural hazards. In this way, it is desirable toinvolve native scientists in large international initiatives, because they know the problem and its particular features. The
benefits will be reciprocal: developing countries could implement actual effective policies to control the natural hazards,
minimizing the number of victims, and geosciences could
take maximum advantage of these natural tragic events to improve their theories and models.

The geophysical variables in developed countries havestrongly been studied, and their new developments are related
to improving already high accurate models (climate, gravity,
magnetism, etc.) over these regions. However, the modern observing techniques, especially satellite measurements,
have demonstrated that some models present poor quality in a
global scale. The new observations show special and uniquegeophysical features, that are located in regions of developing countries. They define the geophysical behaviour of thewhole Earth, but they have been neglected in many precedent models, because they were not observed. This leads
to building a homogeneous in situ observation set that permits to control and improve the global observation networks
and the space-borne measurements, making accurate global
models reliable. From this point of view, the participationof developing countries in the improvement of geodetic andgeophysical models has to be direct, not only by supplying
field observations to scientists of industrialized countries, butalso by specialising their knowledge on the particular conditions. Examples are El Niño, electro jet effect, strong gravity
gradients, volcanoes and geological faults, etc.

11.6 Sustainable development
In the new century, the scientific disciplines have renewed
their compromise to serve to improvement the quality oflife for mankind. The industrialized countries concentrate
their efforts in controlling climate and environmental problems to maintain their high standards of life; however, they
are sharing the same environment with non-developed countries, whose alternatives to follow the same way are inexistent. Overlooking the current problems in developing countries will generate environmental damages on a global scale.
In this way, one of the main purposes should be to enable people and organisations in these countries to improve their living conditions through their own efforts, alleviating poverty,
protecting the environment and natural resources and improving educational quality. Geosciences, under the umbrella of
IUGG, should promote the planning and implementation ofprojects and programmes of technical cooperation in the areas of its Associations, the main tasks being soils, water, environment, mineral resources, energy resources, mining/waste
deposits as well as geohazards. The overall goal is the satisfaction of basic needs, sustainable economic development,

11.4 Importance of geosciences in themodern society, and especially indeveloping countries
Although a lot of work has been done to promote geoscientificinformation to the public in many countries, population andadministrators have very limited knowledge of geosciences,and of its importance inside society. In developing countries,
the popularization of geosciences is worse than in the industrialized ones, being limited and hindered by many factors.
Two important aspects are, firstly, the restricted purchasing
power of people and the relatively small investments in education, culture and technology, and secondly, the decreasing
public support for research funding in geosciences. The use102

management of natural resources and protection from geohazards, as well as sector related spatial and regional planning.

In these countries, normally, professionals working in geosciences do not know about the existence and advantagesof international organisations like IUGG or its Associations,
who are offering a world-wide setting to improve their daily
activities. At this level, the scientists of developing countries, who are involved in the IUGG (or its Associations),
are requested to promote among their national (regional) colleagues the offered opportunities to participate in the international structure of geosciences, improving directly their experience, knowledge and quality results. The traditional conviction of the industrialized countries about the insufficientcapability of developing countries to assume important rolesin scientific advances, and the ”natural” feeling of the developing countries to be under classified to make only supplementary activities must disappear. Scientists from developing countries have to improve their performance. This implies that the scientists must put forth a very strong effort,
since their education and infrastructural facilities are not goodenough to allow equal status with the advanced nations, but
this ”hard work” should be done. They can not always wait
for the heritage of the ”developed” world. In contrast, thescientists of the developed nations, who are exploring newinvestigation fields or are applying older ones in developing
countries, should leave their overconfidence and share the
new methodologies and discoveries with the national scientists. They should understand, that the transfer of technology
is not only ceding used equipments.

11.7 Transferring technology and improving scientific level
The best way to improve the performance (knowledge, development, applications) of geoscientific research in developing countries is through teaching, research and services,increasing new geoscience ideas and concepts and preparing
scientists of these countries. Specialists are needed in linking scientific understanding of resources and environmentswith other disciplines, such as public policy and law, to ensure proper land use planning. However, this should be donein a critical manner, methods used in industrialized countries
should not be applied directly to developing countries. They
should be adapted to the specific conditions and characteristics of the region and its people. This should be done instrict cooperation with the local scientists and entities thatare working in geosciences. In this way, IUGG should assist, in particular, the developing countries in the training ofoperational personnel and research scientists, and in the dissemination and use of research outputs. IUGG should also
take a leading role in ensuring free and unrestricted international exchange of geophysical data and products, and ensure
the availability of scientific journals and other research results
related to geosciences and to the developing countries.
The solution of the problems in developing countries requires interventions from Earth sciences. IUGG should participate in this challenge and develop strategies for the reliable assessment of natural resources and for optimising theirrational use. To support this process, progress in geosciences
and modern observing technologies should be used to develop
appropriate databases to support research and operational activities through international initiatives that invite the active
participation of developing countries.

11.9 Scientific cooperation beyond political and economical denominations
There are many examples of projects where scientists of developed and not developed nations have worked well and arestill working in close cooperation with large benefits bothways. Just to mention some of them:
SIRGAS (Geocentric Reference System for the Americas) provides a modern reference frame for positioning (definition of station coordinates) in the new continent. It allows
the formulation of new programs and projects, which conduce
South America to study, understand and apply the most recent
developments of geodesy (http://www.ibge.gov.br/sirgas). As
a consequence of the successful performance of SIRGAS a
similar project is starting in Africa (AFREF: African Reference System)
INTERMAGNET (International Real-time magnetic
observatory network) to monitoring the Earth’s magnetic
field. It allows the improvement of the technological infrastructure in magnetic observatories in developing countries, interchanging information and investigation programs(http://www.intermanet.org).

11.8 The role of developing countries
in geosciences
The above items summarize some important aspects that
IUGG should address to support the performance of geosciences in developing countries. However, this cannot bea ”one-way” process; the developing countries have to understand how important geosciences are to improve their disadvantageous conditions and try to participate more actively
in the new challenges. Unfortunately, geosciences are notvery popular among policy makers, administrators and the
public in general, not only in the industrialized nations, butalso in the developing countries, where the applicability ofgeosciences and their products is almost totally unknown.
103LBA-Hydro Net is a regional electronic hydrometeorological data network to support water sciences
and water resource assessment in South America, Central
America and the Caribbean (http://cig.ensmp.fr/ iahs)
The Alliance initiative stimulates the intensive collaboration between all meteorological and atmospheric entities
world-wide, providing special attention to the most vulnerable environments (http://iamas.org/iamas2002/alliance)
The EMI program (Earthquakes and mega cities initiative) promotes and coordinates multidisciplinary research
related to the mitigation of the social, economic and environmental impact of earthquakes in big cities.
This list is far from complete, but it testifies to the need andto successful results of joint work between industrialized anddeveloping countries. In the same way, the discussions andfuture views presented in the other ten chapters of this reportoffer an extended catalogue of opportunities to formulate andexecute joint projects in the next decade, making closer ties
between the developed and less developed nations. Formulating specific projects to be conducted only by developing
countries makes no sense; this would help to increase the already existing gap. Developed and non-developed countries
are sharing one and the same Earth, and geosciences can not
be classified into ”geosciences for developed countries” and”geosciences for non-developed countries;” geosciences, as
the Earth, are the same world-wide! The next lines present
some recommendations related to the role of IUGG and its
Associations to realise the equal participation of developing
countries in modern geoscience-projects:
Educational programs with international level quality:
IUGG and its Associations should try to minimize the educational lack in geosciences existing in some developing
countries. One alternative is creating an ”Educational Service” that supports evaluation and improvement through recommendations of present educational programs at universities of developing countries. It should also include a staff ofscientists who are disposed to teach and train ”in situ” or invite scientists of developing countries. This service should
also procure the formulation and execution of actualization
schools, where the scientists from developing countries (alsofrom developed ones) can ”refresh” their knowledge according to the recent technological advances. The creation ofinter-institutional master and doctor degrees promoted by the
IUGG and its Associations should be seen as the major objective of this Educational Service.
Coordinate research management: A central focus ofIUGG and its Associations is to integrate scientists of developing countries into the long-term investigation programs (e.
g. the new satellite gravity missions, global change, etc). The
commissions, sub-commissions, study groups and the otherstructural issues of IUGG and its Association should also include scientists from developing countries, whose participation in meetings (general assemblies, symposia, workshops)
must be guaranteed by IUGG.

Balance between fundamental research and their applications: Nowadays, there is an actual disconnect between thescientific developments (represented by complex research advances) and their practical applications (the implementationof the developed approaches in the field). While scientists
in industrialized nations focus on issues like resolution, uncertainty and accuracy of observing techniques, analyses andpredictions, there are not always well-trained professionals
in developing counties who can focus on providing practical solutions by applying those big advances. Therefore, itis necessary to improve the knowledge of fundamental theory in developing countries and give support and guidance togenerate solutions to real problems of society in developingworld.
Exchange of scientists: IUGG and its Associations should
procure the interchange of scientists from developed and nondeveloped countries. The ”developed” scientists can improve techniques and methods in observatories (or institutions in general) of developing countries by long-term visitsthat should also serve to train and transfer new concepts anddata analysis strategies. Scientists from developing countries
hosted in scientific institutions or observatories in industrialized nations will have direct contact with the recent status of geosciences analysed by large infrastructures that can
provide innumerable tools to improve their developments intheir respective nations. In a more general point of view, this
could help scientists to discuss logistical and procedural matters across international boundaries to improve overall data
quality acquisition, modelling and application.

11.10 Conclusions
The discussion about developing countries getting the same
status as the industrialized nations is matter of all levels ofsociety, world-wide organizations (governmental and nongovernmental) and policy makers. The existing gap is only
a consequence of the big economical differences that regulate the disadvantageous life in the non-developed countries. Maybe the scientific and technological advances in geosciences are not a priority for these nations, whose permanent
fight concentrates on daily survival. These differences will
not disappear in the near future, but more than 80% of theworld belongs to the ”non-developed” people, and they can
not be ignored by geosciences and their up coming activities.
If they are, what are geosciences for?

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Chapter 12Conclusions
E. E. Brodsky

ulated in each section are primarily scientific questions
rather than engineering ones. This identification of extensive basic scientific needs supports the assertion in
the introduction that governments, funding agencies andprofessional societies must support basic science financially and intellectually at a level comparable to appliedscience.

Through the discussions of this report, a few broad themes
have emerged. We see prediction as a major long-range goalof all fields, whether it be prediction of earthquakes, eruptionsor space weather. In some fields, like meterology, oceanography and hydrology, scientists should aim to not only predict
events, but ultimately, to control them.
In the more immediate future, we recommend the following general priorities for geoscientists and the associations
that represent them.

3. At the same time as basic science is being pursued, geoscientists need to continue to put their short-term results
to use. Knowledge transfer can be successfully accomplished by utilizing mass media outlets as well as more
traditional advisories to policymakers. The web andtelevision are likely the best ways to reach the youth audience, a key demographic in ensuring the future of the
field. Regular, continued press communications fromIUGG could be a useful tool for sustained results.

1. Interdisciplinary studies are clearly crucial to making
progress in all of the fields in this report. The Earth andits environs are complex systems where the physics does
not partition itself into neat compartments. The need fortrue crossing of boundaries is so great that we recommend that IUGG rethink the boundaries between associations. Most of the current member associations of
IUGG have their origins in the first half of the twentiethcentury when the fields of geoscience were radically different than today. It no longer makes sense to segregate
freshwater from salt water scientists or those that measure the Earth’s deformation via satellite from those that
use the same satellites to measure ionospheric perturbations. There are also major new disciplines that haveemerged that are currently unrepresented in the structureof IUGG. Where do physicists who study surface processes fit in or chemical physicists who explain the fractionation of isotopes? What about planetary scientists?
Even the distinction between geophysicists as opposedto geochemists or geologists has become blurred in practice. In order to become an effective society for modern
scientists, IUGG must grapple with the new shape of the
fields.

4. Geoscience is intrinsically a global science. The internet and expansion of digital data has recently enhanced
our ability to collect and distribute data and model results across all fields and nations. Such data distribution
is enhancing interdisciplinary collaborations by improving individual investigators ability to combine datasets.
The new openness could be a boon to scientists in developing countries who can now, in principle, enjoy equal
access to state-of-the-art datasets and model results. In
order to make the promises of the digital age a reality,
existing data centers must be expanded and new ones
begun for currently unrepresented disciplines. In particular, this report cites the need for volcanic, hydrological,
and space physics data and modeling centers. These centers must provide free, unrestricted access to all users.
5. Massive datasets and numerical models have both become possible in recent years. One of the most significant challenges facing all areas of geoscience is to combine the new data with state of the art models to better
understand the complex systems in nature. Both model
validation and incorporating the data in the model are

2. All disciplines represented here found significant motivation in the societal benefits of their science. We also
see that a healthy future of the field requires emphasison basic science. Not every project needs to be tied to a
specific benefit for society. The short-range goals artic105

important. One methodology that is gaining momentum
in all fields is data assimilation, i.e., using a weighted
combination of observations and theoretical constraints
to produce predictions of future behavior. Such combinations will be a key component of progress in naturalsciences in the near future.
6. The coupling between spheres of geoscience is often
lost at the interface between sciences. Regional models could be a useful tool for both uncovering these
couplings and answering specific scientific problems.
Regional models are defined by a specific geographic
area rather than a methodology. Studies could focus
on a locale such as the East Pacific rise or the Antarctic sky. Combined expertise from all the relevant disciplines would help to quantify the observed processes
and, more importantly, elucidate which interactions between spheres are quantitatively important.
7. High-resolution Earth system studies pose challenges
for both data collection and modeling. Dense observations need to be taken to resolve the physics of suchhighly variable processes, such as turbulence and othersubgridscale phenomena. Once these dense measurements are collected, the scale dependence of parameters must be investigated. In addition, incorporatingthese findings into global models is challenging in every field. For example, hydrologists have discovered that
fundamental parameters, like permeability, depend significantly on the scale of observation. Similar discoveries probably await investigators in other fields. New
models must incorporate this inherent feature of natural
systems.
8. All of the associations noticed the importance of studies
on other planets as a method of testing and expanding
their current understanding. As discussed in the Interdisciplinary Chapter, IUGG should consider formalizing
its activity in this important frontier by forming an interassociation body or even a new association.
The working group hopes that both the general and subjectspecific recommendations of this report may provide a usefulframework for much exciting science to come. We look forward to being part of the future of geoscience.

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