International Seminar on Nuclear War and Planetary Emergencies: 30th Session: Fourth Centenary of the Foundation of the First Academy of Sciences: 'Academia Lynceorum' by Federico Cesi and Pope Clemente VIII, Erice, Italy 18 - 26 August 2003

INTERNATIONAL SEMINAR ON

NUCLEAR WAR AND PLANETARY EMERGENCIES 30th Session: ANNIVERSARY CELEBRATIONS:THE PONTIFICALACADEMY OF SCIENCES4WlX -THE “€TIORE MAIORANA‘ FOUNDATION AND CENTRE FOR SCIENTlf IC CULTURE 4OTH - H H JOHN PAUL I1 AI’OSTOLATE 25TH - CLIMATE/GLOUAL WARMING THE COSMIC RAY EFFECT; EFFECTS ON SPECIES AND BIODIVERSITY;HUMAN EFFECTS;PALEOCLIMATE IMPLICATIONS EVIDENCT FOR GLOBAL WARMING -POLLUTION: E ” 3 I N E DISRUFflNG CHEMICALS; HAZARDOUS MATERIAL; LEGACY WASTES AND RADIOACTIVEWASTE MANAGEMENT IN USA, EUROPE, SOUTHEASTASIA AND JAPAN -THE CULTURALPLANETARY EMERGENCY: ROLE OF THE MEDIA: INTOLERANCE;TERRORISM; IRAQI PERSPECTIVE;OPEN FORUM DEBATE -AIDS AND INFEcnOUS DISEASES: R W C S IN MEDICINE;AIDS VACCINE SIIWEGIES -WATER WATER CONFLICTS IN THE MIDDLE EAST -ENERGY: DEVELOPING COUNTRIES; MITIGATION O f GREENHOUSEWARMING -PERMANENT MONITORING PANELS REPORTS-WORKSHOPS: LONG-TERMSTEWARDSHIPOF HAZARDOUS MATERIAL; AIDS VACCINE STRATEGIESAND ETIHICS

THE SCIENCE AND CULTURE SERIES Nuclear Strategy and Peace Technology

Series Editor: Antonino Zichichi

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International Seminar on Nuclear War - 1st Session: The World-wide Implications of Nuclear War

1982

1984 -

International Seminar on Nuclear War - 2nd Session: How to Avoid a Nuclear War

1983

International Seminar on Nuclear War - 3rd Session: The Technical Basis for Peace

1981

International Seminar on Nuclear War - 4th Session: The Nuclear Winter and the New Defence Systems: Problems and Perspectives

1985 - International Seminar on Nuclear War - 5th Session: SDI, Computer Simulation, New Proposals to Stop the Arms Race 1986

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International Seminar on Nuclear War - 6th Session: InternationalCooperation: The Alternatives

1987

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International Seminar on Nuclear War - 7th Session: The Great Projects for Scientific Collaboration East-West-North-South

1988

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International Seminar on Nuclear War - 8th Session: The New Threats: Space and Chemical Weapons - What Can be Done with the Retired I.N.F. Missiles-LaserTechnology

1989

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International Seminar on Nuclear War - 9th Session: The New Emergencies

1990 - International Seminar on Nuclear War - 10th Session: The New Role of Science 1991 - International Seminar on Nuclear War - 11th Session: Planetary Emergencies 1991 - International Seminar on Nuclear War - 12th Session: Science Confronted with War (unpublished) 1991 - International Seminar on Nuclear War and Planetary Emergencies - 13th Session: Satellite Monitoring of the Global Environment (unpublished) 1992

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International Seminar on Nuclear War and Planetary Emergencies - 14th Session: Innovative Technologies for Cleaning the Environment

1992

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International Seminar on Nuclear War and Planetary Emergencies - 15th Session (1st Seminar after Rio): Science and Technology to Save the Earth (unpublished)

1992

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International Seminar on Nuclear War and Planetary Emergencies - 16th Session (2nd Seminar after Rio): Proliferationof Weapons for Mass Destructionand Cooperation on Defence Systems

1993

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International Seminar on Planetary Emergencies - 17th Workshop: The Collision of an Asteroid or Comet with the Earth (unpublished)

1993 - International Seminar on Nuclear War and Planetary Emergencies - 18th Session (4th Seminar after Rio): Global Stability Through Disarmament 1994

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International Seminar on Nuclear War and Planetary Emergencies - 19th Session (5th Seminar after Rio): Science after the Cold War

1995

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International Seminar on Nuclear War and Planetary Emergencies - 20th Session (6th Seminar after Rio): The Role of Science in the Third Millennium

1996

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International Seminar on Nuclear War and Planetary Emergencies - 21st Session (7th Seminar after Rio): New Epidemics, Second Cold War, Decommissioning, Terrorism and Proliferation

1997 - International Seminar on Nuclear War and Planetary Emergencies -22nd Session (8th Seminar after Rio): Nuclear Submarine Decontamination, Chemical Stockpiled Weapons, New Epidemics, Cloning of Genes, New Military Threats, Global Planetary Changes, Cosmic Objects & Energy 1998 - International Seminar on Nuclear War and Planetary Emergencies - 23rd Session (9th Seminar after Rio): Medicine & Biotechnologies,Proliferation 8, Weapons of Mass Destruction, Climatology & El Nino, Desertification,Defence Against Cosmic Objects, Water & Pollution, Food, Energy, Limits of Development, The Role of Permanent Monitoring Panels 1999

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International Seminar on Nuclear War and Planetary Emergencies -24th Session: HIV/AIDS Vaccine Needs, Biotechnology, Neuropathologies, Development Sustainability- Focus Africa, Climate and Weather Predictions, Energy, Water, Weapons of Mass Destruction,The Role of Permanent Monitoring Panels, HIV Think Tank Workshop, Fertility Problems Workshop

2000

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InternationalSeminar on Nuclear War and Planetary Emergencies - 25th Session: Water - Pollution, Biotechnology- Transgenic Plant Vaccine, Energy, Black Sea Pollution, Aids - Mother-Infant HIV Transmission, Transmissible Spongiform Encephalopathy, Limits of Development - Megacities, Missile Proliferation and Defense, Information Security, Cosmic Objects, Desertification,Carbon Sequestration and Sustainability, Climatic Changes, Global Monitoring of Planet, Mathematics and Democracy, Science and Journalism, Permanent Monitoring Panel Reports, Water for MegacitiesWorkshop, Black Sea Workshop, Transgenic Plants Workshop, Research Resources Workshop, Mother-Infant HIV TransmissionWorkshop, Sequestrationand DesertificationWorkshop, Focus Africa Workshop

2001

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International Seminar on Nuclear War and Planetary Emergencies -26th Session: AIDS and Infectious Diseases - Medicationor Vaccination for DevelopingCountries; Missile Proliferationand Defense; Tchernobyl - Mathematics and Democracy; Transmissible Spongiform Encephalopathy; Floods and Extreme Weather Events Coastal Zone Problems; Science and Technology for Developing Countries; Water Transboundary Water Conflicts; Climatic Changes -Global Monitoring of the Planet; Information Security; Pollution in the Caspian Sea; Permanent Monitoring Panels Reports; Transmissible Spongiform Encephalopathy Workshop; AIDS and Infectious Diseases Workshop; Pollution Workshop

2002 - International Seminar on Nuclear War and Planetary Emergencies - 27th Session: Society and Structures: Historical Perspectives - Culture and Ideology; National and Regional Geopolitical Issues; Globalization- Economy and Culture; Human Rights - Freedom and Democracy Debate; Confrontations and Countermeasures: Present and Future Confrontations; Psychology of Terrorism; Defensive Countermeasures; Preventive Countermeasures; General Debate; Science and Technology: Emergencies; Pollution, Climate - Greenhouse Effect: Desertification,Water Pollution, Algal Bloom; Brain and Behaviour Diseases; The Cultural Emergency: General Debate and Conclusions; Permanent Monitoring Panel Reports; Information Security Workshop; Kangaroo Mother’s Care Workshop; Brain and Behaviour Diseases Workshop

2003 - International Seminar on Nuclear War and Planetary Emergencies - 29th Session: Society and Structures: Culture and Ideology- Equity Territorial and Economics - Psychology -Tools and Countermeasures -Worldwide Stability - Risk Analysis for Terrorism -The Asymmetric Threat -America’s New “Exceptionalism” - Militant lslamist Groups Motives and Mindsets-Analysing the New Approach The Psychology of Crowds - Cultural Relativism- Economic and Socio-economic Causes and Consequences - The Problems of American Foreign Policy UnderstandingBiological Risk Chemical Threats and Responses - Bioterrorism Nuclear Survivial Criticalities Responding to the Threats - National Security and Scientific Openness - Working Groups Reports and Recommendations

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2004 - International Seminar on Nuclear War and Planetary Emergencies- 30th Session: Anniversary Celebrations: The Pontifical Academy of Sciences 400th -The ‘Ettore Majorana’ Foundation and Centre for Scientific Culture 40th - H.H. John Paul II Apostolate 25th -Climate/Global Warming: The Cosmic Ray Effect; Effectson Species and Biodiversity; Human Effects; Paleoclimate Implications; Evidence for Global Warming - Pollution: Endocrine Disrupting Chemicals; Hazardous Material; Legacy Wastes and Radioactive Waste Management in USA, Europe; Southeast Asia and Japan -The Cultural Planetary Emergency: Role of the Media; Intolerance; Terrorism; Iraqi Perspective; Open Forum Debate - AIDS and Infectious Diseases: Ethics in Medicine; AIDS Vaccine Strategies -Water: Water Conflicts in the Middle East - Energy: Developing Countries; Mitigation of Greenhouse Warming Permanent Monitoring Panels Reports - Workshops: Long-TermStewardship of Hazardous Material; AIDS Vaccine Strategies and Ethics

THE SCIENCE AND CULTURE SERIES

Nuclear Strategy and Peace Technology

"E. Majorana" Centre for Scientific Culture Erice, Italy, 18-26 August 2003

Series editor and Chairman: A. Zichichi

edited by R. Ragaini

r pWorld Scientific NEWJERSEY

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LONDON

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SINGAPORE

- SHANGHAI

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HONGXONG

- TAIPEI - C H E N N A I

Published by World Scientific Publishing Co. Re. Ltd. 5 Toh Tuck Link, Singapore 596224 USA ofice: Suite 202, 1060 Main Street, River Edge, NJ 07661

UK ofice: 57 Shelton Street, Covent Garden, London WC2H 9HE

INTERNATIONAL SEMINAR ON NUCLEAR WAR AND PLANETARY EMERGENCIES 30m SESSION: ANNIVERSARY CELEBRATIONS: THE PONTIFICAL ACADEMY OF SCIENCES 400m -THE 'ETTORE MAJORANA' FOUNDATION AND CENTRE FOR SCIENTIFIC CULTURE 40m-H.H. JOHN PAUL I1 APOSTOLATE 25'"- CLIMATEKLOBAL WARMING: THE COSMIC RAY EFFECT; EFFECTS ON SPECIES AND BIODIVERSITY; HUMAN EFFECTS; PALEOCLIMATE IMPLICATIONS; EVIDENCE FOR GLOBAL WARMING - POLLUTION ENDOCRINE DISRUPTING CHEMICALS; HAZARDOUS MATERIAL; LEGACY WASTES AND RADIOACTIVE WASTE MANAGEMENT IN USA, EUROPE; SOUTHEAST ASIA AND JAPAN-THE CULTURAL PLANETARYEMERGENCY: ROLE OF THE MEDIA; INTOLERANCE; TERRORISM; IRAQI PERSPECTIVE; OPEN FORUM DEBATE -AIDS AND INFECTIOUS DISEASES: ETHICS IN MEDICINE; AIDS VACCINE STRATEGIES - WATER: WATER CONFLICTS IN THE MIDDLE EAST - ENERGY: DEVELOPING COUNTRIES; MITIGATION OF GREENHOUSE WARMING - PERMANENT MONITORING PANELS REPORTS - WORKSHOPS: LONG-TERM STEWARDSHIP OF HAZARDOUS MATERIAL; AIDS VACCINE STRATEGIES AND ETHICS

Copyright 0 2004 by World Scientific Publishing Co. Pte. Ltd. All rights reserved. This book, orparts thereoj may not be reproduced inanyformorby any means, electronic or mechanical, including photocopying, recording or any information storage and retrieval system now known or to be invented, without written permission from the Publisher.

For photocopying of material in this volume, please pay a copying fee through the Copyright Clearance Center, Inc., 222 Rosewood Drive, Danvers, MA 01923, USA. In this case permission to photocopy is not required from the publisher.

ISBN 981-238-820-6

Printed in Singapore.

vii

CONTENTS 1.

CELEBRATIONS

Marcel0 Sdnchez Sorondo The Pontifical Academy of Sciences Alan Cook Improving Natural Knowledge: The First Hundred Years of the Royal Society, 16661760

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15

Guy Ourisson

The Acad6mie des Sciences and French Centralisation

21

Antonino Zickichi The 40th Anniversary of the ‘Ettore Majorana’Foundation and Centre for Scientific Culture

28

Arnold Burgen The Academia Europaea

41

Rocco ButtigIione The 25th Anniversary of the Apostolate of H.H. John Paul I1

2.

CLIMATE: GLOBAL WARMING

Nir J. Shaviv Climate Change and the Cosmic Ray Connection

47

A. Townsend Peterson Climate Change Effects on Species and Biodiversity

59

B.D. Santer and T.M.L. Wigley New Fingerprints of Human Effects on Climate

69

Michael E. Mann Paleoclimate Implications for Recent Human Influence on Climate

86

David Parker and Chris.Folland Evidence for Global Warming

92

viii

3.

ENDOCRINE DISRUPTING CHEMICALS

J.I? Myers, L.J. Guillette, Jx, I? Palanza, S. Parmigiani, S.H. Swan and KS. vom Saal The Emerging Science of Endocrine Disruption

4.

105

POLLUTION: LONG-TERM STEWARDSHIP OF HAZARDOUS MATERIAL

Carlo Giovanardi The Italian Policy for Waste Management and the Co-operation with the International Scientific Community

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James H. Clarke, Lome G. Everett and Stephen J.Kowall Containment of Legacy Wastes During Stewardship

125

William R. Fmdenburg @resented by James H. Clarke) Public Involvement and Communication in the Long-Term Management of U.S. Nuclear Waste Sites

130

AIIan G. Duncan A European Perspective on StakeholderInvolvement in Nuclear Waste Management

135

Balamurugan Gurusamy Hazardous Waste Management in SoutheastAsia

140

Tomio Kawata Responding to Fermi’s Warning: Japanese Approach to Dealing with Radioactive Waste Problems

150

Stephen J. KowaIl The U.S. Approach to the Science and Technology of Legacy Waste Management

157

5.

THECULTURAL PLANETARY EMERGENCY: FOLEOF THE MEDIA

Michael Stunner Spin in War and Peace

163

ix

6.

THECULTURAL PLANETARY EMERGENCY

Ahmad Kamal Cultural Intolerance

169

Antonio Marzano The Impact of the Planetary Emergencies on Worldwide Productivity and Cooperation with the International Scientific Community

174

Kctor Kremenyuk War on Terrorism: A Search for Focus

180

Hussain Al-Shahristani Iraq After Saddam: An Iraqi Perspective

184

7.

AIDS AND INFECTIOUS DISEASES: ETHICS IN MEDICINE

Diego Buriot Health and Security: SevereAcute Respiratory Syndrome ( S A R S ) : Taking a New Threat Seriously

191

Udo Schiiklenk Professional Responsibilities of Biomedical Scientists in Public Discourse

196

J L . Hutton Ethics, Justice and Statistics

212

Ivan FranCa-Junior Is Access to HIV/AIDS Treatment a Human Right? Lessons Learned from the Brazilian Experience

218

8.

AIDS AND INFECTIOUS DISEASES: AIDS VACCINE STRATEGIES

Jorma Hinkula, Claudia Devito, Bartek Zuber, Franco M. Buonaguro, Reinhold Benthin, Britta Wahren and UUSchroder Systemic and Mucosal Immune Responses Induced by HIV-1 DNA and HIV-Peptide or VLP Booster Immunization

229

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Rigmor Thorstensson Pre-clinical Primate Vaccine Studies

243

Efwhia Vardas Preparing for Phase 1/11HIV Vaccine Trials in South Africa and Planning for Phase I11 Trials

247

9.

WATER CONFLICTS

Farhang Mehr The Politics of Water

255

Maher Salman and Wael Mualla The Utilization of Water Resources for Agriculture in Syria: Analysis of the Current Situation and Future Challenges

263

Uri Shavit, Ran Holtzman, Michal Segal, Ittai Gavrieli, Efrat Farber and Avner Vengosh The Lower Jordan River

275

Munther J. Haddadin Challenges to Water Management in the Middle East

289

Shad Sorek, K Borisov, A. Yakirevich,A. Melloul and S. Shaath Seawater Intrusion into the Gaza Coastal Aquifer as an Example for Water and Environment Inter-linked Actions

299

10.

THEPLANETARY EMERGENCIES: ITALIAN CIVIL PROTECTION

Guido Bertolaso The Italian Civil Protection Response to Planetary Emergencies and the Co-operation with the International Scientific Community (Kdeo)

11.

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THECULTURAL PLANETARY EMERGENCY Focus ON TERRORISM: MOTIVATIONS

Ahmad Kamal Report of the Open Forum Debate on Terrorism

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12.

ENERGY

Hishani Khatib Energy in Developing Countries - Is It a Special Case?

317

Bob van der Zwaan Some Perspectives on the Prospects of Nuclear Energy in the Developing World and Asia

326

Norman J; Rosenberg, R. Cesar Izaurralde and I;: Blaine Metting Applications of Biotechnology to Mitigation of Greenhouse Warming 335

13.

PERMANENT MONITORING PANEL MEETINGS AND REPORTS

Mother and Child Permanent Monitoring Panel Nathalie Charpak Panel Report

349

Limits of Development Permanent Monitoring Panel Hiltmar Schubert Panel Report

351

Albert0 Gonzalez-Pozo Urban Mobility in the Mexican Metropolis

359

K.C. Sivaramakrishnan Mobility in Megacities: Indian Scenario

374

World Federation of Scientists Permanent Monitoring Panel on Information Security Henning Wegener Panel Report

383

Henning Wegenel; Elliam A. Barletta, Olivia Bosch, Dmitry Chereshkin,Ahmad Kamal, Andrey Krutskikh, Axel H.R. Lehmann, Timothy L. Thomas, vitali Tsygichko and Jody R. Westby -Paper Toward a Universal Order of Cyberspace: Managing Threats from Cybercrime to Cybenvar

385

xii

Permanent Monitoring Panels on Floods and Unexpected Meteorological Events, Water and Climate Robert Clark Panel Report

43 6

Pollution Permanent Monitoring Panel Richard C. Ragaini Panel Report

43 9

Energy Permanent Monitoring Panel Richard Wilson Panel Report

443

Joseph Chahoud Syria’s Renewable Energy Master Plan: A Message from the Government

456

Andrei Gagarinski Status of Nuclear Energy

47 1

Mark D. Levine Energy Demand Growth in China: The Crucial Role of Energy Efficiency Programs

477

Risk Analysis Permanent Monitoring Panel Terence Taylor Panel Report

488

Andrey A. Piontkovshy The Pillars of International Security: Traditions Challenged

490

vladimir B. Britkov Safety as a Result of Providing Information

495

Reiner K. Huber Anticipatory Defense: Its Fundamental Logic and Implications

498

Desertification Permanent Monitoring Panel Andrew Warren Panel Report

512

xiii

Endocrine Disrupting Chemicals Permanent Monitoring Panel Stefan0 Parmigian i Panel Report

14.

516

LONG-TERM STEWARDSHIP OF HAZARDOUS MATERIAL WORKSHOP

Stephen J. Kowall and Lorne G. Everett Monitoring and Stewardship of Legacy Nuclear and Hazardous Waste Sites

519

Elizabeth K. Hocking Achieving Stewardship and Contributing to a Sustainable Society Through Stakeholder Involvement

522

A.I. Rybalchenko Radioactive Waste of Defense Activities in the 20th Century Handling and Management

526

David K. Smith, Richard B. Knap, Nina D. Rosenberg and Andrew EB. Tompson International Cooperation to Address the Radioactive Legacy in States of the Former Soviet Union

534

Igor S. Zektser Contamination and Vulnerability of Groundwater Resources in Russia

545

15.

AIDS VACCINE STRATEGIES AND ETHICS IN INFECTIOUS DISEASES WORKSHOP Joint Working Group Report of AIDS and Infectious Diseases PMP and Mother and Child Health PMP

Seminar Participants

55 1

557

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1.

CELEBRATIONS

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THE PONTIFICAL ACADEMY OF SCIENCES

MARCEL0 S h C H E Z SORONDO Chancellor Pontificia Academia Scientiarum, Rome, The Vatican See: Dialogo; Specola Vaticana THE NATURE AND GOALS OF THE ACADEMY The Pontifical Academy of Sciences has its origins in the Accademia dei Lincei ('the Academy of Lynxes') which was established in Rome in 1603, under the patronage of Pope Clement VIII, by the learned Roman Prince, Federico Cesi. The leader of this Academy was the famous scientist, Galileo Galilei. It was dissolved after the death of its founder but then recreated by Pope Pius IX in 1847 and given the name 'Accademia Pontificia dei Nuovi Lincei' ('the Pontifical Academy of the New Lynxes'). Pope Pius XI then re-founded the Academy in 1936 and gave it its present name, bestowing upon it statutes which were subsequentlyupdated by Paul VI in 1976 and by John Paul II in 1986. Since 1936 the Pontifical Academy of Sciences has been concerned both with investigating specific scientific subjects belonging to individual disciplines and with the promotion of interdisciplinary co-operation. It has progressively increased the number of its Academicians and the international character of its membership. The Academy is an independent body within the Holy See and enjoys freedom of research. Although its rebirth was the result of an initiative promoted by the Roman Pontiff and it is under the direct protection of the ruling Pope, it organises its own activities in an autonomous way in line with the goals which are set out in its statutes: 'The Pontifical Academy of Sciences has as its goal the promotion of the progress of the mathematical, physical and natural sciences, and the study of related epistemological questions and issues' (Statutes of 1976, art.2, 1). Its deliberations and the studies it engages in, like the membership of its Academicians, are not influenced by factors of a national, political or religious character. For this reason, the Academy is a valuable source of objective scientific information which is made available to the Holy See and to the international scientific community. Today, the work of the Academy covers six main areas: a) fundamental science; b) the science and technology of global questions and issues; c) science in favour of the problems of the Third World; d) the ethics and politics of science; e) bioethics; and fl epistemology. The disciplines involved are sub-divided into nine fields: the disciplines of physics and related disciplines; astronomy; chemistry; the earth and environment sciences; the life sciences (botany, agronomy, zoology, genetics, molecular biology, biochemistry, the neurosciences, surgery); mathematics; the applied sciences; and the philosophy and history of sciences. The new members of the Academy are elected by the body of Academicians and are chosen from men and women of every race and religion on the basis of the high scientific value of their activities and their high moral profile. They are then officially appointed by the Roman Pontiff. The Academy is governed by a President, appointed from its members by the Pope, who is helped by a scientific Council and by the Chancellor. Initially made up of eighty Academicians, of whom seventy were appointed for life, in 1986 John Paul II raised the number of members for life to eighty, side by side with a limited number of Honorary Academicians chosen because they are highly qualified figures, and others who are Academicians because of the

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posts they hold, amongst whom: the Chancellor of the Academy, the Director of the Vatican Observatory, the Prefect of the Vatican Apostolic Library, and the Prefect of the Vatican Secret Archive. In conformity with the goals set out in its statutes, the Pontifical Academy of Sciences 'a) holds plenary sessions of the Academicians; b) organises meetings directed towards the progress of science and the solution of technical-scientific problems which are thought to be especially important for the development of the peoples of the world; c) promotes scientific inquiries and research which can contribute, in the relevant places and organisations, to the investigation of moral, social and spiritual questions; d) organises conferences and celebrations; e) is responsible for the publication of the deliberations of its own meetings, of the results of the scientific research and the studies of Academicians and other scientists' (Statutes of 1976, art. 3, 9 1). To this end, traditional 'study-weeks' are organised and specific 'working-groups' are established. The headquarters of the Academy is the 'Casina Pi0 IV',a small villa built by the famous architect Piero Ligorio in 1561 as the summer residence of the Pope of the time. Surrounded by the lawns, shrubbery and trees of the Vatican Gardens, frescoes, stuccoes, mosaics, and fountains from the sixteenth century can be admired within its precincts. Every two years the Academy awards its 'Pius XI Medal', a prize which was established in 1961 by John XXUI. This medal is given to a young scientist who has distinguished himself or herself at an international level because of his or her scientific achievements. Amongst the publications of the Academy, reference should be made to three series: Scriuta Varia, Documenta, and Commentarii. The most important works, such as for example the papers produced by the study-weeks and the conferences, are published in the Scriuta Varia. In a smaller format, the Documenta series publishes the short texts produced by various activities, as well as the speeches by the Popes or the declarations of the Academicians on subjects of special contemporary relevance. The Commentarii series contains articles, observations and comments of a largely monographic character on specific scientific subjects. The expenses incurred by the activities of the Academy are met by the Holy See. During its various decades of activity, the Academy has had a number of Nobel Prize winners amongst its members, many of whom were appointed Academicians before they received this prestigious international award. Amongst these should be listed Lord Ernest Rutherford (Nobel Prize for Physics, 1908), Guglielmo Marconi (Physics, 1909), Alexis Carrel (Physiology, 1912), Max von Laue (Physics, 1914), Max Planck (Physics, 1918), Niels Bohr (Physics, 1922), Werner Heisenberg (Physics, 1932), Paul Dirac (Physics, 1933), Erwin Schroedinger (Physics, 1933), Sir Alexander Fleming (Physiology, 1945), Chen Ning Yang (Physics, 1957), Rudolf L. Mossbauer (Physics, 1961), Max F. Perutz (Chemistry, 1962), John Eccles (Physiology, 1963), Charles H. Townes (Physics, 1964), Manfred Eigen and George Porter (Chemistry, 1967), Har Gobind Khorana and Marshall W. Nirenberg (Physiology, 1968). Recent Nobel Prize winners who have also been, or are presently, Academicians may also be listed: Christian de Duve (Physiology, 1974), Werner Arber and George E. Palade (Physiology, 1974), David Baltimore (Physiology, 1975), Aage Bohr (Physics, 1975), Abdus Salam (Physics, 1979), Paul Berg (Chemistry, 1980), Kai Siegbahn (Physics, 1981), Sune Bergstrom (Physiology, 1982), Car10 Rubbia (Physics, 1984), Rita Levi-Montalcini (Physiology, 1986), John C. Polan9 (Chemistry, 1986), Jean-Marie Lehn (Chemistry, 1987), Joseph E. Murray (Physiology, 1990), Gary S. Becker (Economics, 1992), Paul J. Crutzen (Chemistry,

5 1995), Claude Cohen-Tannoudji (Physics, 1997) and Ahmed H. Zewail (Chemistry, 1999). Padre Agostino Gemelli (1878-1959), the founder of the Catholic University of the Sacred Heart and President of the Academy after its re-foundation until 1959, and Mons. Georges Lemaftre (1894-1966), one of the fathers of contemporary cosmology who held the office of President from 1960 to 1966, were eminent Academicians of the past. Under the Presidency of the Brazilian biophysicist Carlos Chagas and of his successor Giovanni Battista Marini-Bettblo, the Academy linked its activity of scientific research to the promotion of peace and the progress of the peoples of the world, and dedicated increasing attention to the scientific and health care problems of the Third World. The Presidency of the Academy is presently entrusted to the Italian physicist, Nicola Cabibbo. The goals and the hopes of the Academy, within the context of the dialogue between science and faith, were expressed by Pius XI (1922-1939) in the following way in the Motu Proprio which brought about its re-foundation: 'Amongst the many consolations with which divine Goodness has wished to make happy the years of our Pontificate, I am happy to place that of our having being able to see not a few of those who dedicate themselves to the studies of the sciences mature their attitude and their intellectual approach towards religion. Science, when it is real cognition, is never in contrast with the truth of the Christian faith. Indeed, as is well known to those who study the history of science, it must be recognised on the one hand that the Roman Pontiffs and the Catholic Church have always fostered the research of the learned in the experimental field as well, and on the other hand that such research has opened up the way to the defence of the deposit of supernatural truths entrusted to the Church...We promise again, and it is our strongly-held intention, that the 'Pontifical Academicians', through their work and our Institution, work ever more and ever more effectively for the progress of the sciences. Of them we do not ask anything else, since in this praiseworthy intent and this noble work is that service in favour of the truth that we expect ofthem'(AAS28, 1936, p. 427; Italian translation, OR, 31.10.1936). After more than forty years, John Paul II once again emphasised the role and the goals of the Academy at the time of his first speech to the Academicians which was given on 10 November 1979 to commemorate the centenary of the birth of Albert Einstein: 'the existence of this Pontifical Academy of Sciences, of which in its ancient ancestry Galileo was a member and of which today eminent scientists are members, without any form of ethnic or religious discrimination, is a visible sign, raised amongst the peoples of the world, of the profound harmony that can exist between the truths of science and the truths of faith...The Church of Rome together with all the Churches spread throughout the world, attributes a great importance to the function of the Pontifical Academy of Sciences. The title of 'Pontifical' given to the Academy means, as you know, the interest and the commitment of the Church, in different forms from the ancient patronage, but no less profound and effective in character. As the lamented and distinguished President of the Academy, Monsignor Lemaitre, observed: 'Does the Church need science? But for the Christian nothing that is human is foreign to him. How could the Church have lacked interest in the most noble of the occupations which are most strictly human - the search for truth? Both believing scientists and non-believing scientists are involved in deciphering the palimpsest of nature which has been built in a rather complex way, where the traces of the different stages of the long evolution of the world have been covered over and mixed up. The believer, perhaps, has the advantage of knowing that the puzzle has a solution, that the underlying writing is in the final analysis the work of an intelligent being, and that

6 thus the problem posed by nature has been posed to be solved and that its difficulty is without doubt proportionate to the present or future capacity of humanity. This, perhaps, will not give him new resources for the investigation engaged in. But it will contribute to maintaining him in that healthy optimism without which a sustained effort cannot be engaged in for long' ('Discorso alla Pontificia Accademia delle Scienze, 10.11.1979', inhegnumenti, II, 2 (1979), pp. 1119-1120). It was precisely in that speech that John Paul II formally called on historians, theologians and scientists to examine again in detail the Galileo case. And he asked them to do this 'in the faithful recognition of errors, by whomsoever committed', in order to 'remove the distrust that this case still generates, in the minds of many people, placing obstacles thereby in the way of fruitful concord between science and faith' (ibidem, pp. 1117-1118). A HISTORICAL SURVEY: FROM THE ACCADEMIA DEI LINCEI TO TODAY'S PONTIFICAL ACADEMY OF SCIENCES The historical itinerary of the Academy is summarised in the articles written by Marini-Bettolo (1986) and by Marchesi (1988), and in broader fashion in the monograph by Regis Ladous (1994). As was observed at the beginning of this paper, the roots of the Pontifical Academy of Sciences are to be traced back to the post-Renaissance epoch. Its origins go back to the ancient Accademia dei Lincei, established in 1603 by Prince Federico Cesi (1585-1630) when he had just reached the age of eighteen. Cesi was a botanist and naturalist, the son of the Duke of Acquasparta, and a member of a noble Roman family. Three other young men took part in this initiative: Giovanni Heck, a Dutch physician aged twenty-seven; Francesco Stelluti di Fabriano; and Anastasio de Filiis de Temi. Thus it was that the first Academy dedicated to the sciences came into being, and it took its place at the side of the other Academies - of literature, history, philosophy and art - which had arisen in the humanistic climate of the Renaissance. The example of Cesi, and of the group of scholars led by him, was followed some years later in other countries - the Royal Society was created in London in 1662 and the AcadCmie des Sciences was established in France in 1666. Although he looked back to the model of the Aristotelian-Platonic Academy, his aim was altogether special and innovative. Cesi wanted with his Academicians to create a method of research based upon observation, experiment, and the inductive method. He thus called this Academy 'dei Lincei' because the scientists which adhered to it had to have eyes as sharp as lynxes in order to penetrate the secrets of nature, observing it at both microscopic and macroscopic levels. Seeking to observe the universe in all its dimensions, the 'Lincei' made use of the microscope (tubulus opticus) and the telescope (perspicillus-occhialino)in their scientific research, and extended the horizon of knowledge fiom the extremely small to the extremely large. Federico bestowed his own motto on the 'Lincei' - 'minima cura si maxima vis' ('take care of small things if you want to obtain the greatest results'). The Cesi group was also interested in the new scientific and naturalistic discoveries then coming fiom the New World, as is demonstrated by the most significant works of the college of the first 'Lincei' - the Rerum medicarum thesaurus novae Hispaniae, later known as the Tesoro Messicano, which was printed in Rome in 1628. This was a very extensive collection of new geographical and naturalistic knowledge, and contained in addition accounts of explorations canied out in the

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Americas. From the outset the Academy had its ups and downs. A few years after its foundation it was strongly obstructed by Cesi's father because he believed that within it activity was being engaged in which was not very transparent in character - for example, studies in alchemy. But after the death of Federico's father, the abundant economic resources which were now obtained thanks to Federico's inheritance, as well as the fact that renowned scholars such as Galileo Galilei, Giovan Battista della Porta, Fabio Colonna, and Cassiano dal Pozzo joined its ranks, enabled the Academy to progress and advance. The religious character of the Academy cannot be overlooked. It was placed under the protection of St. John the Evangelist who was often portrayed in the miniatures of its publications with an eagle and a lynx, both of which were symbols of sight and reason. It was therefore conceived as an assembly of scholars whose goal as one can read in its Rules, described as the 'Linceografo' - was 'knowledge and wisdom of things to be obtained not only through living together with honesty and piety, but with the further goal of communicating them peacefully to men without causing any harm'. Nature was seen not only as a subject of study but also of contemplation. Amongst the suggestions of the 'Linceografo' there is also that of preceding study and work with prayer - 'for this reason the Lynxes, before doing anything at all, must first raise their minds to God, and humbly pray to him and invoke the intercession of the saints' (cf. di Rovasenda and Marini-Bettblo, 1986, p. 18). Amongst the practices of spiritual piety of the members there was the reciting of the liturgical office of the Blessed Virgin Mary and the Davidic Psalter. For this reason, as Enrico di Rovesanda observes, 'the religious inspiration of the Lincei cannot be overlooked, as is done in many quarters, nor can it be reduced to an 'almost mystical glow of the school of Pythagoras', as has also been suggested. The high moral figure of Cesi acts to guarantee the sincere and loyal profession of its religious faith' (ibidem, p. 19). One of the mottoes of the Academy - Sapientiae cupidi - indicated the striving for constant research into truth through scientific speculation, based upon the mathematical and natural sciences but always located within a sapiential horizon. Like Galileo, whose great supporter he was, Cesi admired Aristotle but not the Aristotelians of the University of Padua who had refused to look at things through the telescope of the Pisan scientist. He was in addition rather critical of the university culture of his day. Federico Cesi also engaged in important activity of mediation between the Roman theological world and Galileo, reaching the point of advising the latter to not insist in his polemics about the interpretation of Holy Scripture so that he could dedicate himself in a more effective way to scientific research. Death struck Cesi down in 1630 when Galileo was about to finish his Dialog0 sui Massimi Sistemi, the manuscript of which Galileo wanted to send to Cesi himself so that the latter could organise its publication. After Cesi's death the activities of the Academy diminished to such an extent as to bring about its closure. The first attempts to bring the 'Lincei' back into existence took place in 1745 in Rimini as a result of the efforts of a group of scientists belonging to the circle made up of Giovanni Paolo Siomne Bianchi (known as Janus Plancus), Stefan0 Galli and Giuseppe Garampi. But the new Academy had a very short life. The attempt at refoundation made by Padre Feliciano Scarpellini (1762-1840) in Rome at the beginning of the nineteenth century met with greater success. He gave the name of 'Lincei' to a private academy that he had established in 1795. Despite a lack of funds and a whole series of difficulties, Scarpellini managed to keep the name of 'Lincei' alive and to

8 bring together in a single academic body the various scientists working in the Papal States such as the mathematician Domenico Chelini, the naturalist Carlo Bonaparte, the anatomist Alessandro Flajani, the chemists Domenico Morichini and Pietro Peretti, Prince Baldassarre Odescalchi, the physicists Gioacchino Pessuti and Paolo Volpicelli, and the physician Benedetto Viale (cf. Marini-Bettblo, 1986, p. 10). The authorities of the Papal States took new practical initiatives to re-found the Academy during the first half of the nineteenth century in response to the wishes of Pope Pius VII (1800-1823) and Leo XII (1823-1829), with the allocation of the second floor of Palazzo Senatorio in Capidoglio to the Academy as its headquarters. But in 1847 it was Pius IX who officially renewed the Academy with the name (which had already been suggested by Gregory XVI in 1838) of 'Accademia Pontificia dei Nuovi Lincei' ('the Pontifical Academy of the New Lynxes'), ensuring the drawing up of new statutes which envisaged, amongst other things, the presence of thirty resident members and forty correspondent members. During this period of activity famous astronomers and priests were present within its ranks, such as Francesco de Vico and Angelo Secchi. During the revolutionary upheavals of 1848 the Roman Republic sought to expel the Academy from the Campidoglio. However, the institution managed to keep its headquarters by using various bureaucratic manoeuvres. In 1870, following the fall of the independent Papal States and the unification of the Kingdom of Italy, the Academy divided into two different institutions: the 'Reale Accademia dei Lincei', which later became the present Accademia Nazionale dei Lincei with its headquarters in Palazzo Corsini alla Lungara, and the 'Accademia Pontificia dei Nuovi Lincei', which was transferred from the Capidoglio to the Casina Pi0 IV villa in the Vatican Gardens. One had to wait, as has already been observed, until 28 October 1936 for a further renewal of the institution, which took place in response to the insistent requests of the Jesuit Giuseppe Gianfranceschi. This scientist was Professor of Physics at the Gregorian University and had been the President of the Accademia Pontificia dei Nuovi Lincei since 1921. A new Pontifical Academy of Sciences was thus created by Pope XI by the Motu Proprio In Multis Solaciis (for an Italian translation see Marini-Bettblo, 1987, pp. 199-203. This work has an accurate summary of the life of the Academy for the years 1936-1986). The Presidency was entrusted to the Rector of the Catholic University, Padre Agostino Gemelli, who was seconded by the Chancellor, Pietro Salviucci, and by a Council composed of four Academicians. Annual (and later two-yearly) plenary sessions were proposed for all the Academicians. The accounts of the activities and the contributions of the members were published in the Acta Pontijiciae Academiae Scientiarum and later on in the Commentationes. The first assembly was inaugurated on 1 June 1937 by the then Cardinal Secretary of State, Eugenio Pacelli, the future Pope Pius XII. In discussing this period of the Academy reference should be made to the presence of such distinguished members as Ugo Armaldi, Giuseppe Armellini, Niels Bohr, Lucien Cuenot, Georges Lemaitre, Tullio Levi-Civita, Guglielmo Marconi, Robert Millikan, Umberto Nobile, Max Planck, Ernest Rutherford, Erwin Shrodinger, Francesco Seven, Edmund Whittaker, and Pieter Zeeman. During the years 1937-1946 the publications of the Academy had a largely Italian character, presenting, for example, the work of the Italian Academicians Pistolesi, Crocco, and Nobile on aerodynamics. But there were also papers by foreign Academicians such those as by E. Schrodinger in 1937 on quantum physics and by M. Tibor in 1937-1939 of an astronomical character. During the Second World War the

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Academy greatly reduced its activity but nonetheless found space for the publications of Jewish Italian scientists who had been marginalised by the race laws of 1938, amongst whom should be mentioned a group of mathematicians of Jewish descent including Tullio Levi-Civita and Vito Volterra, and others such as Giuseppe Levi, Rita Levi-Montalcini, E. FOB and G.S. Coen. Pius XI1 (1939-1958), who succeeded Pius X, did not fail to make addresses to the Academicians, even during the war years, such as the address of 30 November 1941 on the occasion of the inauguration of the fourth academic year. This address was dedicated to a long and profound reflection on the position of man in relation to the Creation and God (cf. Discorsi e Radiomessaggi, III,pp. 271-281). In the post-war period, at a time of sensitive reconstruction and the rebuilding of international relations, in the face of the great difficulties encountered at the level of scientific contacts and exchange, the Academy undertook the publication of the research results of greatest interest of the various fields of science which had been achieved during the war in its work Relationes de Auctis Scientiis ternpore belli (aa. 1939-1945). This publication was of marked importance in fostering the renewal of scientific contacts between the nations that had previously been at war. In 1946 Alexander Fleming (188 1 - 1955) was appointed Academician in recognition of his discovery of penicillin - a discovery that opened the way to the pharmacological production of antibiotics. During the 1950s, in parallel with the problems of reconstruction and the development of under-developed regions, the activity of the Pontifical Academy of Sciences centred around the questions and issues of applied science. In 1955 the study-week on trace elements was held, when for the first time the problem of agrarian production and food sources was addressed. After the election to the papacy of John XXIIl (1958), Padre Gemelli died in 1959. The Presidency of the Academy was then held by G. Lemaitre. The 1960s witnessed an exponential growth and development of science connected with electronics and the conquest of space. This gave new impetus to industry and technological advance but also to nuclear armaments. In astrophysics the discovery of new sensors and the development of radio-astronomy opened up the universe to new interpretations. Biology became directed towards the molecular study of genetics. In 1961 the Pontifical Academy of Sciences organised a study-week on the macromolecules of interest to biology, and in particular on the nucleoproteins, a subject which was then of major importance for international research. On that occasion, when meeting the Academicians, John XXIII reaffirmed the educational and cultural mission of the Church and the function of scientific progress in relation to the positive appreciation of the human person. The Pope recalled in addition that science is directed above all else towards the development and growth of the personality of man and the glorification of God the Creator: 'indeed, far from fearing the most audacious discoveries of men, the Church instead believes that every advance in the possession of the truth involves a development of the human person and constitutes a road towards the first truth, and the glorification of the creative work of God' ('Discorso in occasione del XXV dell'Accademia, 30.10.1961', in Discorsi, Messaggi e Colloqui del Santo Padre Giovanni XXlII, vol. III,p. 493). In 1962, at the time of the plenary session of that year, a study-week dedicated to astronomy which addressed the subject of cosmic radiation in space was held, guided in first person by the President of the Academy, Monsignor Lemaitre. In 1964, at the time of the pontificate of Paul VI (1963-1978), there appeared

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amongst the publications of the Pontifical Academy of Sciences the Miscellanea Galileiana of Monsignor Pi0 Paschini, who was Professor of History at the Lateran University. The Galileo case was slowly reopened, a development favoured by the reference made to it by Vatican Council II in n. 36 of Gaudium et Spes. This led to the address by John Paul 11 of 1979 to which reference has already been made. After the death of Georges Lemaitre, in 1966 Padre Daniel OConnell was made President of the Academy. A Jesuit and Irish astronomer, he had previously been Director of the Vatican Observatory and had been an Academician for life since 1964. He was also the author, together with other astronomers, of an important general atlas of the stars. The year 1967 was marked by the publication of the encyclical Popularurn Progressio, in which Paul VI brought to worldwide attention all the major problems inherent in the development of the Third World. This document also contained an appeal to engage in international scientific co-operation so that this could in all forms favour developing countries. It introduced the idea that scientific progress and advance must be guided by a 'new humanism': 'every advance of ours, each one of our syntheses reveals something about the design which presides over the universal order of beings, the effort of man and humanity to progress. We are searching for a new humanism, which will allow modem man to refind himself, taking on the higher values of love, fiiendship, prayer and contemplation' (n. 20). In harmony with the themes of the encyclical, the Academy thought it was necessary to open itself to collaboration with the scientists of the Third World and by 1968 it was already holding a study-week on the subject of 'organic matter and soil fertility', a subject which dealt with the application of science to agricultural production and the solution to the problems of hunger in the world. In 1972 for the first time a secular President was elected - the Brazilian Carlos Chagas, who had already been a member of the United Nations and the General Secretary of the first conference of the United Nations on Science and Technologies for Development. The new President imparted a new direction to the activities of the Academy, which were now more centred around solving the great problems of post-industrial society (cf. di Rovesanda, 2000). The scientific activity of the Academy was thus directed not only towards the subjects of science, which were more specific to Westem culture, but also began to be concerned, with the co-operation of Giovanni Battista Marini-Bettblo (who succeeded Chagas in 19SS), with the scientific and health care problems connected with the growth and development of the Third World ('development ethics'). The 1980s witnessed the development of new directions in scientific research which moved in the direction of the life sciences, the earth sciences, and ecology. Mankind had to face up to new problems, such as pollution, changes in the biosphere, energy reserves, and genetic manipulation. In 1982 the Academy committed itself at an international level to the promotion of peace with the drawing up of a document on nuclear armaments (cf. 'Dichiarazione sul disarm0 nucleare' ('Declaration on Nuclear Disarmament'), EV, 7, pp. 1811-1825) and devoted the next plenary session (of 1983) to the subject of 'science for peace'. In connection with that event, John Paul II appealed to members of governments to work in an effective fashion in order to remove the danger of a new war and invited States to engage in nuclear disarmament (cf. 'a sapere scientific0 edifichi la pace, 12.11.1983' ('Scientific Knowledge should Build Peace, 12.11.1983'), in Znsegnamenti, VI, 2 (1983), pp. 1054-1060). This document and appeal achieved a strong resonance in the United States of America and the Soviet Union. During the 1990s meetings and study-weeks were held which were

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dedicated to analysing the question of the prolonging of life; the question of determining the moment of death; the question of transplants and xenografts; and the question of sustainable growth and development. The issues of artificial fertilisation, cloning, and genetic manipulation were also considered. These were subjects which increasingly involved issues of an ethical character (bioethics) and which drew scientists, philosophers and theologians into dialogue. Although the usual practice of involving various disciplines was maintained, the research and the debates of the Academicians were directed in a special way towards reflection on the anthropological and humanistic dimensions of science. In November 1999 a working-group was held on the subject of 'science for man and man for science', and the Jubilee session of November 2000 was dedicated to the subject 'science and the future of mankind'. THE ROLE OF THE ACADEMY IN THE DIALOGUE BETWEEN SCIENTIFIC THOUGHT AND CHRISTIAN FAITH

In the relations which exist between Academies and the States in which they carry out their activities, the case of the Pontifical Academy of Sciences can be seen as a singular case, as indeed in basic terms the role of the small State which hosts it is also singular. During these long years this relationship has become very fertile. The Church has paid careful attention to the Academy. She has respected its work and fostered the autonomy of its scientific and organisational dynamics. Through the Academy, the Magisterium of the Church has sought to make the scientific world understand her teaching and her orientations in relation to subjects which concern the good of man and society, the complete human development of all the peoples of the world, and the scientific and cultural co-operation which should animate the relations between States. On the occasion of numerous addresses and messages directed towards the Academy by five pontiffs, the Church has been able to re-propose the meaning of the relationship between faith and reason, between science and wisdom, and between love for truth and the search for God. But through the Academy the Church has also been able to understand from nearer to hand, with speed and in depth, the contents and the importance of numerous questions and issues which have been the object of the reflection of the scientific world, whose consequences for society, the environment and the lives of individuals could not but interest her directly, 'given that there is nothing which is genuinely human which does not find echo in her heart' (cf. Gaudium et S p a , 1). The Pontifical Academy of Sciences has thus become one of the favoured forums for the dialogue between the Gospel and scientific culture, gathering together all the stimulating provocations but also the inspiring possibilities that such dialogue brings with it, almost thereby symbolising a shared growth - of both the scientific community and the Magisterium of the Church - of their respective responsibilities towards truth and good. The above survey, although general in character, dealing with the activity carried out over the sixty years since the foundation of the Pontifical Academy of Science, the subjects of the numerous meetings and study-weeks, and the publications which the Academy has produced, brings out all the contemporary relevance and the importance of the subjects which have been addressed. Scientists from all over the world, often co-operating closely with a group of philosophers and theologians, have examined questions and issues which have ranged from genetics to cosmology, from agriculture to the distribution of resources, fkom transplant surgery to the history of science, and from ecology to telecommunications. The speeches addressed by the

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Pontiffs to the Academicians, from Pius XI to John Paul II, have offered important elements of reflection not only in relation to the ethical and moral responsibility of their activities but also on the very meaning of scientific research, and on its striving for truth and an increasingly profound knowledge of reality. The subject of the relationship between science and faith, both at an epistemological and an anthropological level, has been the usual framework of almost all these papal addresses. The forms of language employed have been different as these decades have passed, and different emphases have been placed on the various questions and issues, but the attention paid to scientific work has been unchanging, as has been the case in relation to the philosophical and cultural dimensions which that work involves. Side by side with such dialogue, which we could call 'ordinary', international public opinion has been witness to certain 'out of the ordinary' events. From the mass media it has learnt about speeches of special importance for the relationship between science and faith, speeches given at the Academy in particular during the pontificate of John Paul II. Of these, reference should be made to the address with which, as has already been observed (see above section I), John Paul 11 spoke to the plenary session of the Pontifical Academy of Sciences in November 1979 to express his wish for, and then formally request, the establishment of a committee of historians, scientists, and theologians which would re-examine the Galileo case and present public opinion with a serene analysis of the facts as they occurred (Galileo, IV).The aim of this was not in a historical sense to recognise the inadvisability of the condemnation of the heliocentrism carried out four centuries beforehand by the Sant'Uffizio (something which had already been effected in 1757 with the removal of the works in question from the list of prohibited books), but rather to ensure that the historical-philosophical context of the episode, as well as its implications at a cultural level, were more illuminated, thereby clarifymg in a public way, which would be comprehensible to everybody, what had already been made clear in a narrower circle of intellectuals and experts. During a new assembly of the Academy, held on 3 1 October 1992, Cardinal Paul Poupard, in the presence of the Holy Father, presented the results of the committee and commented on the work which it had carried out. Four years later, on 22 October 1996, this time in the form of a message on the occasion of the sixtieth anniversary of its re-foundation, John Paul II once again chose the Pontifical Academy of Sciences as a qualified interlocutor to expound certain important reflections on the theory of evolution (Magistero, V.2; Uomo, Identitd Biologica e Culturale, V.3). Returning to and developing certain observations made by his predecessor Pius XII in the encyclical Humuni Generis (cf. DH 3896-3899), he now added that 'new knowledge leads the theory of evolution to no longer be considered as a mere hypothesis', thereby recognising 'that this theory has progressively imposed itself on the attention of researchers following a series of discoveries made in the various disciplines of knowledge', imposing itself also therefore on the attention of theologians and bible experts (Scienze Nuturali, Utilizzo in Teologia). It would not, however, be exact to confine only to recent years the climate of mutual listening and serene encounter on subjects of great relevance. History has also been a witness to other episodes of intense dialogue with the Roman Pontiffs in which the Academy, or some of its members, were the protagonists. This is the case, for example, of Max Planck, who wanted to make himself the interpreter in a direct way with Pius XII in 1943 on the risks of war connected with the use of armaments based upon nuclear fission (cf. Ladous, 1994, p. 144), or the close relationship between Pius

13 XI1 and Georges Lemaitre, who enabled the Pontiff to understand from closer to hand, at the beginning of the 1950s, the meaning of the new cosmological models which were by then beginning to become established in the scientific world, and the philosophical, or even theological, questions which at first sight appeared to be involved (Lemaitre, IV). In more recent years, Carlos Chagas was especially concerned in 1981 to take on the worries of John Paul II, who was still convalescing after the attack on his life, over the consequences for the planet of a possible nuclear war. He decided to himself present the studies carried out on the subject to the principal Heads of State in his capacity as President of the Academy (cf. di Rovesanda, 2000). In the letter sent to Padre George Coyne, the Director of the Vatican Observatory and a member of the Council of the Academy, a document which is certainly one of the most profound there is on the subject of the dialogue between science and faith, John Paul II observed that science has acted to purify faith and that faith has acted to generate scientific research, a truth demonstrated by the fact that modem Galilean science was born in a Christian climate with the increasing assimilation of the message of freedom placed in the heart of man. Thus, in the same letter, referring to the wider context of universities, the Pope declared that: 'The Church and academic institutions, because they represent two institutions which are very different but very important, are mutually involved in the domain of human civilisation and world culture. We carry forward, before God, enormous responsibilities towards the human condition because historically we have had, and we continue to have, a determining influence in the development of ideas and values and the course of human actions' ('Lettera a1 Direttore della Specola Vaticana, 1.6.1988' ('Letter to the Director of the Vatican Observatory, 1.6.1988'), OR 26.10.1988, p. 7.) For this to come about, the Pope stressed the importance of there being experts and places especially dedicated to such a dialogue: 'the Church, for a long time, has recognised the importance of this by founding the Pontifical Academy of Sciences, in which scientists of world-renown regularly meet each other to discuss their research and to communicate, to the wider community, the directions research is taking. But much more is required' (ibidem). And in this 'more' John Paul II saw the need, in their irreplaceable dialogue, for scientific institutions and the Catholic Church not to think in a reductive way about the settling of ancient conflicts, and also saw the more important need for mutual help in the investigation of truth and a shared growth in their responsibility for the good of the peoples of the world and their future. And it was in this logic, with this new readiness to engage in service, that the present President of the Academy, Professor Cabibbo, in his address to John Paul II on the occasion of the Jubilee plenary session on the subject of 'science and the future of mankind' (OR 13-14.11.2000, p. 6) was able to speak about the 'renewed commitment' of the Pontifical Academy of Sciences together with the Holy See to the good of the whole Church, of the scientific community, and of those men and women who search and believe. Pi0 XI, 'Motu proprio De Pontificia Academia Scientiarum, 28.10.1936: in AAS 28 (1936), pp. 421-452; Giovanni Paolo 11, 'Discorso alla Pontificia Accademia delle Scienze in occasione del 1000 anniversario della nascita di A. Einstein, 10.11.1979', in InsegnumentiII, 2 (1979), pp. 1115-1120; 'Discorso inoccasione del 500 della Rifondazione', in Insegnamenti IX, 2 (1986), pp. 1274-1285; 'Discorso in occasione della presentazione dei risultati della Commissione di

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studio sul caso Galileo, 3 1.10.1992',in Insegnamenti XV, 2 (1992), pp. 456-465; 'Messaggio in occasione del 600 della Rifondazione, 22.10.1996: in EV 15, pp. 1346-1354. BIBLIOGRAPHY For studies and works of a historical character see: E. di Rovasenda and G.B. Marini-Bettblo, Federico Cesi nel quarto centenario della nascita (Pontificiae Academiae Scientiarum Scripta Varia, 63, 1986); G.B. Marini-Bettblo, Historical Aspects of the Pontifical Academy of Sciences (Pontificae Academiae Scientiarum Documenta, 21, 1986); G.B. Marini-Bettolo, L'attivitd della Pontijicia Accademia delle Scienze 1936-1986 (Pontificiae Academiae Scientiarum Scripta Varia, 71, 1987); G. Marchesi, 'La Pontificia Accademia delle Scienze, luogo d'incontro tra ragione e fede', Civiltd Cattolica 139 (1988), 111, pp. 235-246; R. Ladous, Des Nobel au Vatican. La fondation de I'academie pontifcale des sciences (Cerf, Paris, 1994); P. Poupard (ed.), La nuova immagine del mondo. I1 dialog0 fra scienza e fede dopo Galileo (Piemme, Casale Monferrato, 1996); E. di Rovasenda, 'In ricordo dell'antico Presidente della Pontifica Accademia delle Scienze, C. Chagas', OR 21-22.2.2000. Some publications of the Academy on subjects referred to in this paper: P. Paschini (ed.), Miscellanea galileana, 3 vols., (Pontificiae Academiae Scientiarum Scripta Varia, 1964); Science and Technology for Developing Countries (Pontificiae Academiae Scientiarum Scripta Varia, 44, 1979); S.M. Pagan0 and A.G. Luciani, I documenti delprocesso di Galileo Galilei (Pontificiae Academiae Scientiarum Scripta Varia, 53, 1984); The Artifcial Prolongation of Life and the Determination of the Exact Moment of Death (Pontificiae Academiae Scientiarum Scripta Varia, 60, 1985); Discorsi indirizzati dai Sommi PonteJici Pi0 XI, Pi0 XI,Giovanni XXIl, Paolo VI, Giovanni Paolo II alla Pontifcia Accademia delle Scienze dal 1936 a1 1986 (Pontificiae Academiae Scientiarum Scripta Varia, 64, 1986); The Responsibility of Science (Pontificiae Academiae Scientiarum Scripta Varia, 80, 1988); Science for Development in a Solidarity Framework (Pontificiae Academiae Scientiarum Documenta, 25, 1989); The Determination of Brain Death and its Relationship to Human Death (Pontificiae Academiae Scientiarum Scripta Varia, 83, 1989); Science in the Context of Human Culture, I-II (Pontificiae Academiae Scientiarum Scripta Varia, 85-86, 1990-199 1); Resources and Population (Pontificiae Academiae Scientiarum Scripta Varia, 87, 1991); The Legal and Ethical Aspects Related to the Project of the Human Genome (Pontificiae Academiae Scientiarum Scripta Varia, 91, 1993); Discorsi dei Papi alla Pontifcia Accademia delle Scienze (1936-1993) (Pontificia Academia Scientiarum, Vatican City, 1994). For all the publications of the Pontifical Academy of Sciences see Publications of the Pontijical Academy of Sciences (1936-1999) (Vatican City, 1999).

IMPROVING NATURAL KNOWLEDGE: THE FIRST HUNDRED YEARS OF THE ROYAL SOCIETY 1660 - 1760 SIR ALAN COOK Selwyn College, Cambridge, UK ABSTRACT

In the hundred years from the foundation of the Royal Society in 1660 to the general acceptance of Newtonian dynamics and celestial mechanics by 1760, fellows of the Society advanced theoretical and observational astronomy and biological studies. By 1760 the natural sciences were established as autonomous pursuits with their own aims and methods independent of external authority. The astronomical work of Edmond Halley and John Flamsteed and the biological studies of Leeuwenhoek, John Ray, Stephen Hales and others will be considered, as will, in particular Tycho Brahe, Kepler and Prince Federico Cesi. INTRODUCTION The Royal Society of London for Improving Natural Knowledge was founded in 1660 and by 1760 natural philosophy had taken on some of the principal features of modem science. The dynamics and celestial mechanics of Isaac Newton had become generally accepted throughout Europe; in retrospect we see them as the most spectacular feature of the new science. Newton was not alone, many other Fellows of the Royal Society contributed to develop modem science. I consider something of what they did in theoretical and observational astronomy, in biology and in establishing science as independent and autonomous. Modem science did not begin in 1660. In 2003 it is natural to recognise the achievements of the first fellows of the Accademia dei Lincei, of Galileo of course, but of others beside, and especially of the founder, Prince Federico Cesi. There were other precursors of the Royal Society. Fellows of the Society were familiar with the work of Johannes Kepler that led very directly to Newton’s achievements. If modem science began before 1660, it had not fully attained its present form by 1760. Ideas of history in particular were very far from those of today. For all the debts to the past and unresolved issues for the future, the ideas and methods of science did change greatly in the first century of the Royal Society and fellows of the Society did much to bring that about. The Royal Society was a society of independent scholars. The government neither supported nor directed it but we have a very important privilege in our Royal Charter, granted by Charles I1 in 1662. It conferred the right to print and publish despite the monopoly of the Stationers’ Company of London. Fellows of the Society took advantage of it to publish important works. The Philosophiae naturalis principia mathernatica (1687) of Newton is by far the most influential for the development of modem science, but biological works have also proved very important. Together with the journal, the Philosophical Transactions, and the extensive correspondence camed on by the first secretary of the Society, Henry Oldenburg, they made the studies of fellows of the

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Society known throughout Europe. Robert Boyle, many of whose works European scholars knew and possessed, was the fellow most admired in Europe. The public face of the Society was publishing, the private life was no less important in advancing modem science. Small groups of Fellows were wont to move to some coffee house (numerous in London) after the formal weekly meetings and there to engage in perhaps more speculative talk. Independence, important privileges, an open and sociable community, those were important characteristics of the early decades of the Royal Society when its fellows were advancing natural knowledge and laying the foundations of modem science ASTRONOMY In Rome in 1611 Galileo set up his new telescope on the Gianicolo and Prince Cesi and other Linceans saw for the first time the rough Moon, Venus like a crescent Moon, the satellites of Jupiter, and Saturn with his two ears. Galileo did indeed set astronomy on new paths, but different ways were taken in London fifty years later. London astronomers took up the challenges of understanding the results of Kepler and of improving the methods of Tycho Brahe. Kepler’s laws of planetary motion only made sense for a heliocentric solar system. By about 1680 Christopher Wren, Robert Hooke and Edmond Halley had found that both Kepler’s first law, that the orbit of a planet was an ellipse, and his third law, that the square of the period of a planet is proportional to the cube of its distance from the Sun, implied that the force between the planets and the Sun was as the inverse square of the distance. When the three of them took coffee together in January 1684 after a meeting of the Royal Society, they realised they could not show that an orbit under an inverse square law of force had to be an ellipse. More than six months later Halley visited Newton in Cambridge and put the question to him. Newton’s response became the Philosophiae naturalis principia rnathematica. Halley not only set Newton thinking, he edited the manuscript, saw it through the press and paid for it, and published and sold the book. Only Newton could have written Principia, but without Halley it would not have been born.’ We may not use Newton’s geometry today, the observations for which he had to account were limited indeed compared with the present wealth and extent of physical knowledge, but his methods are still ours - construction of an abstract model, the behaviour of which can be worked out mathematically and comparing it numerically with observation. Kepler’s laws were the challenge that stimulated Newton. John Flamsteed was gripped by the need to improve the catalogue of positions of stars that Tycho Brahe had made, and to do so using the new astronomical techniques that were coming to the fore at about the time of the formation of the Society. Adrien Auzout in Pans and Robert Hooke in London were maintaining that telescopic sights could be used to determine the directions of stars better that the open sights that Brahe (and after him Johann Hevelius) had used. Telescopes were especially effective with a micrometer in the eyepiece. At the same time clock makers in England and France were making the pendulum clock into a precision instrument. If a telescope were mounted on a wall so that it rotated in the meridian, the angle at which a star crossed the meridian, as determined with the

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micrometer telescope, gave the declination of the star, while the time of crossing, measured with a good clock, gave the right ascension. Halley had a micrometer telescope and a good clock when, as a very young man, he spent a year on St Helena and measured the positions of stars not seen from Paris or London. While he could not determine absolute positions, he produced the first catalogue with the new instruments. He became renowned throughout Europe.* Flamsteed meanwhile had been appointed His Majesty’s Astronomer Royal, the only fellow of the Royal Society paid to do science. At first the Society was not directly involved, but after Newton became President in 1704, he was appointed, together with a few other fellows, to be Visitors to oversee the work of the Astronomer Royal. Flamsteed was not pleased. Soon after Halley had come back from St Helena, Flamsteed was able to set up his mural telescope at Greenwich and then for the next forty years devoted himself to his telescopes and producing his Historia Coelestis, containing his observations and the catalogue of fixed stars derived from them. It was a great achievement. Alas, it was obsolete almost as soon as Flamsteed was dead. Halley discovered the proper motion of stars, that they move relative one to another, and James Bradley discovered the aberration of starlight, the composition of the velocity of light with that of the Earth about the Sun. The fixed stars were not fixed as Flamsteed and everyone else had supposed, and future star catalogues would have to allow for that. BIOLOGY The astronomical achievements of fellows of the Royal Society owed more to their predecessors of the north than to Galileo. Biologists among the fellows of the Society clearly took up the same topics as those to which the founders of the Lincei, and especially Prince Cesi himself, had devoted themselves. In 1624 Galileo sent Cesi a microscope, of what construction is not known. With it Cesi made many studies of the anatomy of plants, especially of fungi and seeds.3 Not until the last two decades or so have the scope and originality of his work become known. John Ray however knew about it and referred to it in his Historia Plantarum, though in how much detail is not clear. He learnt of it from a publication of the Lincei that appeared only in 1651, twenty years after Cesi had died. The book was the Mexican Thesaurus, an edited version of the account of Mexican animals and plants produced by the Spanish explorer Francisco Hernandez, to which Fabio Colonna added a note on Cesi’s microscopic studies that Ray quoted almost word for word. Ray also knew of the scheme for the classification of plants that Cesi had d e ~ i s e d .Anatomical ~ studies with the microscope, the first serious attempt at a classification based on the characters of the plants and not on such matters as medical uses, to those were added the first studies of fossils. Cesi’s estates at Acquasparta had large deposits of fossil wood. Cesi identified them as remains of once living trees and studied them microscopically. The Royal Society might be said to be the centre of microscopical anatomy, of plants and animals both, at the end of the seventeenth century. Three notable books were published with the imprimatur of the Society. The Micrographia of Robert Hooke is probably the one the best known today. It is a collection of studies of a wide variety of objects, animal, vegetable and mineral. Nehemiah Grew in The Anatomy of Plants described the structures that he had found in plants by systematic microscopical

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investigations. Marcello Malpighi of Bologna collected his microscopical studies of plants and chicken eggs in his Anatome Vegetale. Antoni van Leeuwenhoek, in the Netherlands, sent his observations to the Society, where some of his specimens still survive among his correspondence. Even John Locke, staying in Montpellier for his health, used a primitive single-lens microscope to study the eggs of insects from which a red dye was made.5 Taxonomy is the study of how living creatures are related in species, genera and so on. John Ray introduced new criteria for classification in the Historia Piscium, an account of fishes that he completed after the death of Frances Willughby.6 The many excellent illustrations made it very expensive and put the Society, which published it, in financial difficulties. Ray broke away, from old schemes based on supposedly authoritative accounts from long ago and instead used external morphology to determine relations between types of fish. That may seem primitive compared with using DNA or breeding habits to determine genetic relations, but it remains the only means by which many fossils can be classified. Later Linnaeus (who knew something of the microscopic work of Cesi) developed his well-known binomial scheme. There seems to be a clear sequence from the classification of Cesi, to that of Ray and then on to Linnaeus. Francisco Stelluti, who published Cesi’s studies of fossils after Cesi’s death, misunderstood them and suppressed or weakened Cesi’s conclusions that the fossils were remains of once-living organisms. Sir George Ent had received samples of Cesi’s wood from Cassiano dal Pozzo and they were shown at meetings of the Royal Society. John Evelyn (in Sylva) and Robert Hooke (in Micrographia) both concluded that they had once been pieces of trees. Fellows of the Royal Society were most certainly interested in fossils, especially objects such as shells that seemed to be like the shells of living creatures, and yet were not the same. John Ray, crossing the Alps from Switzerland into Italy in 1664, saw many in the alpine rocks and considered at some length various ideas about how they came to be, such as God put them there to mystify us. He concluded that they were indeed the remains of creatures that had once lived in a sea where the Alps now were. Robert Hooke in Micrographia, and Edmond Halley, who saw shells in rocks near Harwich on the east coast of England, thought the same.7 By the time of the foundation of the Royal Society, Cesi had been dead for thirty years and it is not easy to assess how well his works were known in England. Many of the drawings that recorded his microscopical studies passed into the collections of Cassiano dal Pozzo. Evelyn and Ray may have learnt of Cesi’s work when they saw dal Pozzo’s collection in Rome in 1644 and 1664 respectively.8 Sir George Ent also corresponded with Cassiano. There are copies of the Mexican Thesaurus in the Royal Society, and the British Library, but not in the University Library, Cambridge. Ray evidently knew it when he came to write the Historia Plantarum, but did he himself have a copy? As for Hooke, Grew and Malpighi, none of them mentioned Cesi. In the early decades of the eighteenth century, Stephen Hales FRS, who died in 1761, introduced new mechanical Newtonian ideas into the study of living creatures with his investigations into blood pressure and flow, published in Haemostasis, and into the rise of sap in plants, published in Vegetable Statics.’ Before him studies of living creatures were essentially anatomical, of structures, he asked how they worked mechanically.

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WHAT IS MODERN SCIENCE?

In what ways can the astronomy and biology of the first century of the Royal Society be said to be ‘modem’? In one important respect our predecessors were not modem. At the end of his life Newton had prepared a general chronology, including biblical chronology, for the personal use of Queen Caroline. After his death it came to be published and drew criticism from Etienne Souciet, a French abbe, who considered that Newton had misdated the Siege of Troy and the Voyage of the Argonauts. Halley came to Newton’s defence in two papers in Philosophical Transactions, arguing that Newton had correctly interpreted the astronomical evidence on which he had based those supposed dates. The distinction we make between myth and history was not yet clear.” What is modem science and what do we mean by it? A few characteristics that developed in the first century of the Royal Society do at least seem essential to modem science. Newly developed instruments, telescopes and microscopes, were used to look further into the heavens and probe deeper into the structures of objects living and inanimate. Clocks became increasingly reliable and precise so that time, once a psychological sensation, became a definite measurable physical variable. Mathematics was used to summarise observations, in the form of statistics, as summary formulae and in incipient set theory. Above all Newton showed how to set up an abstract analogue or model of a natural system, how to work out its behaviour and how to compare that behaviour numerically with observation. Newton and his contemporaries may not have made a clear distinction between history and myth, but they did realise that the world and its contents had not been made once and for all in the relatively recent past. Thus Halley estimated the ages of lakes and seas from their salinity and the rate at which rivers brought in salt. He also indicated that the Moon was speeding up in her orbit about the Earth, and later found the proper motion of stars.” The World was changing. Fossils too, showed that both the rocks and their contents had not always been as they are now. Those were disturbing ideas for traditional preconceptions; they aroused hostility in the 1660’s but were tacitly accepted by many in the 1760’s. New and improved instruments, new discoveries, new ideas, soon became widely known through printed publications. Prince Cesi himself had set that out as a principal aim of his new academy and the Royal Society actively followed his precepts, whether the fellows knew of them or not. The new discoveries would hardly have been made and if made, probably not published, had the Royal Society accepted the authority of the past, or of divines, or of philosophical schemes. The motto of the Royal Society is ‘Nullius in Verba’. Its exact meaning is debatable, but it might be paraphrased as ‘Do not believe text books’. Again, Cesi affords a precedent. In 1615 in a lecture in Naples, Del natural desiderio di supere, he asserted the human duty to study the natural world for itself and to make known the results. He strongly criticised all institutions (universities as well as ecclesiastical authorities and followers of Aristotle) that claimed authority over natural knowledge.12In the course of the first century of the Royal Society, its Fellows helped to establish the idea of science as an autonomous enterprise with its procedures determined by the phenomena being investigated, setting its own aims and methods, and independent of extraneous authority, whether historical, philosophical or religious.

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NOTES See Cook, Alan, Edmond Halley, Charting the heavens and the seas (Oxford, 1998),pp.147, 148. 2. See Cook, loc.cit., (note 1) Ch.3. For Cesi as botanist, see Pignatti, S and Mazzolin, G.: Federico Cesi Botanico, pp. 3. 212- 223, in Convegno celebrativo del IV centenario della nascita di FedericoCesi, (Acquasparta, 7-9 ottobre 1985) Atti dei Convegni Lincei 78, Roma, Academia dei Lincei, 1986. Ray, John, Historia Plantarurn (London, 1674), p.132; Hernandez, Francisco et al. 4. - Rerum Medicarum Novae Hispaniae Zkesaurus seu plantarium, animalium, mineralium MexicanoramHistoria. (Roma, 1651). 5. Hooke, Robert, Micrographia (London 1665); Grew, Nehemiah, Zke Anatomy of Vegetables (London 1672); Malpighi. Marcello, Anatome Plantarum (London 1675); for Locke see Lough, John,1953, John Lockes travels in France, 1675-9. (Cambridge: Cambridge University Press) Ray, John Historia Piscium (London, 6. Evelyn, John, Sylva (London, 1664) pp.95-7. Hooke, Robert, Micrgraphia 7. (London, 1665), PP.105-7, 110-112. Ray, John 1673, Observations topographical physiological and moral (London), 499 pp. + Catalogus Stirpium ; for Halley’s comments, see Journal Book Copy, Royal Society of London, for 1 August 1688. Haskell, F. and McBurney, Henrietta, The Paper Museum of Cassiano dal Pozzo, 8. Visual Resources, 14, (1998), 1-17. The Diuiy of John Evelyn ed. J S de Beer. (Oxford, 1955) Vol 2, p.277. For Ray’s visit to the Cassiano collectiion, see Skippon, Philip, An account of a journey through part of the Low Countries, Germany, Italy and France, in A and J Churchill, 1732, A Collection of Voyages and Travels (London) pp. 361-736 and Index Hales, Stephen, Vegetable Statics (London, 1727); Haemeostaticks, vo1,II of 9. Statical Essays (London, 1733) 10. For Newton’s chronology, see Cook, Halley, loc.cit., (note 1) p. 400 11. See Cook, Halley, loc.cit., (note l), pp. 225-8,346,348-9. 12. For Cesi’s lecture, see Montalenti, Giuseppe, Introduzione a1 Convegno, in Convegno celebrativo del IV centenario della nascita di Federico Cesi, (Acquasparta, 7-9 ottobre 1985, 1oc.cit. (note 3)s. 1.

THE ACADEMIE DES SCIENCES AND FRENCH CENTRALISATION GUY OURISSON AcadCmie des Sciences, Strasburg, France INTRODUCTORY REMARKS

I hope the reader will accept a few highly personal introductory remarks, to explain why I am sensitive to the extent to which France remains defacto deeply, instinctively, Parisocentric, even in an age of global science. I was appointed to the Faculty of Sciences of Strasbourg in 1955 by the General Director of Higher Education in the Ministry. The University of Strasbourg was not consulted. He asked me to promise that I would stay there "at leastfive years", and signed the appointment letter. Fifty years later, after I have, in hundreds of scientific and administrative meetings, forcefully spoken in the name of the non-Parisians, I still meet colleagues or administrators who simply cannot believe that I still do not even have a small flat in Paris. I have been a member of the AcadCmie since 1981. My appointment was signed by the President of the Republic; it carries a pension, something that the French (among others) like very much (although its annual amount is about the monthly minimum wage, but it is drawn directly from the TrCsor Public, from the State's kitty... in earlier times it would have been drawn directly from the King's purse). In 1997, I was elected Vice-president of the Acadtmie, i.e. defacto Presidentelect, and thus in 1999-2001, for the first time ever, a "non-resident" (read: a nonParisian) occupied this exalted position since the foundation of the AcadCmie in 1666. I did in fact reside, Mondays through Thursdays, in a small studio on the premises; however, my successor being of course a Parisian, this studio was converted promptly into offices: the prospect that another "provincial" could be elected as President in the near future is negligible. The AcadCmie des Sciences is still very much a Parisian institution open to nonParisian members. WARNING I am a chemist, not a historian. I therefore feel unable to provide the eminent participants of this meeting with original and learned views, based on my own study of our Archives and revealing original documents. I have consulted our excellent Director of the Archives, Mme Florence Greffe, who gave me the titles of the books I should absolutely read if I wanted to sound informed.' This I did, and my text is based on these readings, as well as on my personal experience. This essay has therefore no historical value, but hopefully may constitute a testimony. GENERAL The word "Academie" (or "AcadCmie") leads to 246,000 Web sites through Google. Many are French sites, and lead to the 5 Academies of the Institut de France, but also to the French National AcadCmies (de MCdecine, de Pharmacie, de Technologies, etc., not part of the Institut de France), to the many regional Academies, often very poor institutions with a very rich and long history, to the US or

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Dutch Academies." The only ones we consider in this Symposium are those we regard to-day as the "National" ones: the Accademia dei Lincei, the Royal Society, the Prussian (now Berlin-Brandenburg) Academy, the National Academies US, and many others, now part of the international "families of Academies" : IAP, IAC, ALLEA.. . and of course the international ones like the Pontifical Academy or Academia Europzea. WHAT DO THESE ACADEMIES DO? One of us used to say, of course only for the French Academie : Theymeet, They vote to change their Statutes, They count their dead,"' They vote to elect new members, They vote to select laureates for their prizes, They meet, they vote, they count.. . .. . This is of course true, but largely incomplete : They also publish, They organise meetings, They prepare reports, They take part in international relations, They foster the creation of useful agencies. Thev mblish: A traditional activity of the Academie has been to publish scientific literature. With their British counterparts the Transactions, the Comptes-Rendus are one of the oldest continuously published scientific journals in the world. Since their heyday in the late XKth Century, they have progressively declined in importance as many more media became available, but they are regaining strength after what appeared to be their demise. They now publish about 10,000 pages of scientific original documents each year; we are however not happy at all with their poor performance as regards citation data. We should not forget that these journals in fact invented the modem publication procedure, where the author submits his publication proposal to one or two referees who advise for or against publication; in modem journals, refereeing is usually done under the cloak of anonymity, whereas in Comptes Rendus, tradition was that you should bring your manuscript in person to one of the members, who would read it and accept it, ask for changes, or reject it. I had to bring my first publication to the very old and powerful Marcel Delepine on a Monday, in his apartment; he asked me courteously to explain it briefly, and it was published the following Monday. I am not sure it deserved such rapid publication. Anyway, now, the process is less personal, referees are not only the Members of the AcadCmie and remain anonymous, but.. . publication takes much longer, even with electronic gadgetry. The AcadCmie also publishes reports, which are examined below. Thev meet and organise meetings: For many years, the meetings of the Academie were used to show Science. Some classical examples are : The presentation of "novel" fossils by Cuvier;

23 The demonstration of the effect of an electric current on a magnetic needle by Arago, following his description to the Academie, the preceding week, of (Ersted's results; The presentation by Pasteur of his sterile vials which he had opened in the clean air of the Mer de Glace; The presentation by Becquerel of his photographic plates which had been darkened not by light but by the "rays" emitted by uranium salts, etc, etc.; The presentation by Friedel of the discovery of radioactivity by Marie and Pierre Curie. Examples abound; but this is all past, and that fashion is apparently gone. In more than 20 years of active participation, I have never seen any experimental demonstration nor any presentation similar to the classical ones mentioned above. However, from the lectures, long or short, presented during our meetings, I have often gathered up-to-date information on the most diverse problems. From the way light passes through holes smaller than its wavelength, to the depth at which Antarctic penguins dive to catch fish; from new materials for car catalytic converters, to the disposal of fission products in a nuclear economy; from the concatenation of molecules into molecular knots or trefoils, to some news about prime numbers, etc. Reading general scientific journals, like Nature or Science, or specialised ones, is of course another way to achieve the same results, but one should not downplay the usefulness of the Academie from that point of view. It is true however that the benefit is restricted to the attendees, that the august Meeting Room is as ill-adapted as possible to presentations to the public, and that most of us have not learnt the delicate art of speaking to the public at large, journalists or TV people, or even to colleagues of other denominations. Another mode of transmission of scientific information is, in my view, much more efficient. It is linked with what has become in recent years a major contribution of the AcadCmie: the organisation of scientific meetings. Some of these are organised in the traditional way, with a roster of invited speakers and a programme leaving some time for discussions; the next one will be on "Water", and its wide-ranging programme will probably attract 200-300 participants. Some of these meetings are organised jointly with another of the National Academies, for instance, with the Academie de MCdecine on medical themes, others with a foreign Academy"'. The original advantage of the AcadCmie in organising these meetings is that it can cut across fields and disciplines more easily than the specialised scientific societies. It can also organise bi-national meetings, and has done so with the Academies of Spain, of the US, of Canada, of Russia and of China. In my personal experience, another useful activity of our AcadCmie has been to take advantage of its solemnity and undisputed seriousness to experiment with other types of meetings. I have personally invested much time in experimenting with a small number of young participants, strictly selected, and secluded in an isolated place for the duration of the meeting : The "Scientia Europa?aB"" meetings brought together 50 young" European scientists for five days, chosen from among approx. 350 nominees proposed as exceptionally good by the various European Academies (+ MPG, + CNRS, etc). "Exceptionally good" people should not require a programme; the posters they presented and discussed defined the programme. Seven such meetings have lured 350 participants from 35 European countries. Unfortunately, this highly successhl experiment

24

requires generous sponsors, and the ones we had found did not fare well on the Stock Market.. . Meetings on multidisciplinary topics, with a group of 20 young European participants, again good enough to take the shock of mixing hard scientists with archaeologists, or even with artists; there again, we met success on themes like "Physics of the isolated molecule" or "Surfaces", perhaps mostly because the good image of the Acadtmie could open the doors of a very beautiful domain in the South Alps for us, in a very generous Foundation. Meetings on organisation problems: a meeting co-organised with the German Leopoldina and the Junge Akademie dealt with a comparison of the problems encountered by young scientists in France and Germany at the beginning oftheir careers. 20 participants: 10 each from each country, 10 administrators of programmes intended to help beginning independent scientists (CNRS, MR, Volkswagen Stiftung, A. von Humboldt Stiftung, MPG.. .), 10 beneficiaries of these programmes. We shall continue. They prepare reports: In the early years of the AcadCmie, the King and his ministers considered it quite normal, as they were spending money on the AcadCmie and its Members, to ask them to contribute to the welfare of the Kingdom. A classic example of this activity has been the search, in France as in England with the Royal Society, of ways to measure longitude at sea: claims of ownership of newly discovered islands depended directly on this mastery, and this depended in turn on the development of reliable and sturdy chronometers. The presence, on the premises of the AcadCmie, of the "Bureau des Longitudes", is testimony to this activity. However, it is rather interesting that there were periods in the 19" century when a request for Reports was considered as an infringement on the real, exalted goals of the AcadCmie, and was quite efficiently resisted until the practice disappeared. Thus, it was a secular revival when, some 30 years ago, our Permanent Secretary Paul Germain obtained from the President of the Republic, Giscard d'Estaing, the request to prepare a report on "The state of mechanics in France". This led to intense work, and to the publication of the first "modem" report of the AcadCmie. In 1998 again, the President of the Republic, Jacques Chirac, asked the AcadCmie, through its then President Jacques-Louis Lions, to produce a series of reports on some general, worldwide problems. The preparation and publication of these reports demonstrated the capacity of the AcadCmie not only to mobilise its Members, but also to enlist the help of outside scientists - and not only, as some have malignantly suggested, of prospective candidates for election. Emboldened by the success of this endeavour, the AcadCmie suggested and accepted from an Interministerial Committee the charge of preparing Reports on Science and Technology each year, against a reasonable subsidy, which now constitute a major series of highly interesting publications, a sort of encyclopzediaby instalments."" They take part in international relations: Leibniz and Newton were "Membres" of the AcadCmie at its foundation. Note : not "Membres Ctrangers". Science is global ;like the other Academies, the AcadCmie tries to maintain and to enliven a vast network of inter-academic exchanges :

25

It now contains in its membership approximately 140 foreign members; it is true that, for most of them, it is only an honour, but some do take part actively in some of the activities of the AcadCmie; The AcadCmie entertains inter-academic exchanges of ”name-lectures’’ with the Royal Society, the Netherlands Academy, the Lincei; It plays an active role in the international organisations of Academies : the InterAcademy Panel ( U P ) , the InterAcademy Council (IAC), the InterAcademy Medical Panel (IAMP), the All-European Academies (ALLEA), the European Academies Science Advisory Council (EASAC), the ConfCrences Amaldi, and it entertains close relations with ICSU, with the UE, with developing countries (via TWAS), and with the Scientific Unions. It is a rather recent development that the AcadCmie has strengthened its links with the French Foreign Office, in different ways: in selecting scientists to take part in international meetings; in helping some Scientific Councillors of our Embassies to evaluate scientific proposals of subsidies they receive (for meetings, for post-doctoral fellowships, etc.); in using visits of its Members to conference sites to organise informal meetings of their retinue of friends and colleagues with the Scientific Councillors, and thus to enlarge their basis of operations. It is true that the international alibi is not enough to make a useless action a good one. But it is also true that, in the scientific field, an action limited to its national dimensions is most often useless. They foster the creation of useful agencies: Like Queen Victoria (in a probably apocryphal declaration), the AcadCmie “may have little power, but is not devoid of influence”. It has used its influence to obtain the creation of informal organisations that later developed into very important agencies. LA MAIN A LA PATE: This is a programme resulting from the visionary and missionary work of Georges Charpak, Yves QuCrC and Pierre LCna, to innovate the teaching of experimental sciences in primary schools. It started as an experiment, wisely restricted to a few groups of children, and is progressively invading the whole tissue of primary education in France. This imaginative programme remains under the operational control of the Academie, but is being developed progressively, in France and in several foreign countries, notably in China, with the necessary modifications. The Ministry of Education has so far wisely refrained from appropriating this programme, which, despite its success, is still considered by its staunchest proponents as experimental - to avoid the freeze that would result from its transformation into a nation-wide official curriculum. But in a longer perspective, the destiny of La Main ci la Pite is not to be a permanent part of the AcadCmie, which has simply nurtured it, and has probably made it viable by protecting it in its infancy. The same is true of the Fondation nationale Arfred Kastler, which was set up as a service of the AcadCmie to try and improve the way foreign researchers, young or already established, were received in France: to inform them of the formalities before their arrival, to work with our foreign visitors to evaluate what may have been negative during their stay, with the research organisations and ministries to improve these sore points, to try and set up competent offices in the various Universities and

26 research centres to handle local problems, to exchange information between these centres, etc. The "FnAK" is now about ten years old; it has been remarkably successful in its endeavours, and had grown progressively into the largest service of the AcadCmie, budget- and personnel-wise. This very success has led to technical difficulties, and to the decision to find another administrative structure for the FnAK, which is now housed by the CitC Internationale Universitaire de Paris, as an autonomous component of this large organisation. In this case also, the destiny of the FnAK had not been to remain a permanent part of the AcadCmie ; however, it is quite certain that, without the protection of the Academie during the infancy of FnAK, this would not have been taken seriously by the various Ministries and agencies which have accepted to launch it and have ensured its growth. A further word about centralisation. The Academie has recognised, about the time it was getting ready to elect me as its Vice-president, that it now comprised a fair number of non-Parisian members. Our Permanent Secretary, Jean Dercourt, set up a series of meetings outside Paris. In the major Centres, the local Members are asked to set up a programme of two days, organised often in cooperation with the regional AcadCmie. Often, Members "exiled" from these Centers to Paris are invited to participate ; in some cases, their "return" is a major event for the local University and for the local newspapers. It is too early to really gauge the efficacy of these Meetings, but the effort must be pursued. Academies have to invent new ways of remaining useful, if they do not want to become dead bodies: the pride of their members in their membership is not in itself a justification for their perpetuation!

' Some sources : Roger Hahn - The Anatomy of a Scientific Institution - The Paris Academy of Sciences, 16761803, University of California Press, Los Angeles, London, 1971. Maurice Crosland - Science under Control - The French Academy of Sciences 1795-1914, Cambridge University Press, Cambridge, 1992. Elisabeth Badinter - Les Passions intellectuelles, 2 vol. , Fayard, Pans, 1999. Academie des Sciences - Rhglement, usages et science dans la France de I'absolutisme (Proceedings of a Colloquium - 1999), Lavoisier, Paris, 2002. li Also to the French regional administrative divisions of the Ministry of Education called AcadBmies, to Dance or Soccer Academies, to Billiard Academies, etc.

li' The total Membership of the Academie was defined, not the annual flux of new Members as in some other Academies. Counting the dead used therefore to be an important occupation. Now, it is the total number of Members under 80 years of age.

List of Symposia organised on the premises of the Acaddmie in 2002 and 2003: "Transferts de matiere a la surface de la terre" "Effet de sene : impacts et solutions. Quelle credihilite ?" "Cellules souches et therapie cellulaire" "L'irnmunite innee - De la drosophile a l'homme" "Chimie et nanosciences" "Les risques nucleaires" "Les risques chimiques" "La skurite sur la toile Internet" and two of the most recent inter-academy ones : "Chemistry and Mathematics : two scient$c languages ofthe 21" Century", organised by the Leopoldina with the participation of the Gattingen Academy and Academie des Sciences iv

27

"L'immunitd inn& - De la drosophile ci I'homme", organised with the Academy of Medical Sciences (UK)

" Registered trade-mark of the Academie. "I "Youth"should be defmed. I usually propose saying that "young" means no more than 5 years oldet than myself. However, in the case of the Scientia E u r o p m meetings, the limit was fixed at 40 years old.

vii

. ..

. . . .. . a

List of the Reports published by the AcadCmie. Etudes sur l'environnement - De l'echelle du territoire a celle du continent, De la transgenese animale a la biotherapie chez l'homme Les plantes genetiquement modifiees Rapport biennal sur la science et la technologie en France - Synthese 1998-2000 Systematique - Ordonner la diversite du Vivant Le monde vegetal - Du genome a la plante entiere Sciences aux temps ultracourts - De l'attoseconde aux petawatts La statistique Systemes rnoleculaires organises - Carrefour de disciplines I'origine de developpements industriels considerables La chimie analytique - Mesure et socikte Materiaux du nucleaire Radiochimie - Matiere radioactive et rayonnements ionisants Le medicament / Medicinal drugs Physiologie animale et humaine - Vers une physiologie integrative / Animal and human physiology - a step towards integrative physiology Developpement et applications de la genomique - L'aprks-genome Les neurosciences fonctionnelles et cognitives : recherches sur la physiologie et les pathologies du systeme nerveux Exploitation et surexploitation des ressources marines vivantes Stratospheric ozone Contamination des sols par les elements en traces: les risques et leur gestion / Soil contamination by rare elements: risk management L'ozone stratospherique Impact de la flotte aerienne sur I'environnement atrnospherique et le c h a t / The impact of aircraft fleets on the atmospheric environment and on the climate Aspects moleculaires, cellulaires et physiologiques des effets du cannabis / Molecular, cellular and physiological considerations appertaining to the effects of cannabis Problems associated with effects of low doses of ionising radiations Pollution atmospherique due aux transports et sante publique / Atmospheric pollution caused by transportaion and its effects on public health L'avenir de la recherche universitaire - Le devenir des docteurs des universites frangaises Valorisations non alimentaires et non Bnergetiques des produits agricoles / Development of tgricultural products for purposes other than food or energy Etat de la recherche toxicologique en France La recherche scientifique et technique dans le domaine de 1'6nergie Perspectives Bducatives des formations techniques et professionnelles. L'appareil &information sur la science et la technique Quelle place pour la m6trologie en France a l'aube du 216 Siecle ?

THE 40th ANNIVERSARY OF THE ‘ETTORE MAJORANA’ FOUNDATION AND CENTER FOR SCIENTIFIC CULTURE ANTONINO ZICHICHI CERN, Geneva, Switzerland and University of Bologna, Italy Over the course of the last 40 years, eighty-six thousand scientists from one hundred and forty nations have taken part in post-university activities that have rallied around the banner of a Science without secrets and without frontiers. This scientific community has striven to break down ideological, political and racial barriers that were invented not by Science, but by its worst enemies. The very existence of a scientific community as vast as that of Erice serves as concrete evidence that the new role of Science has already become a reality. To conduct Science means to discover the Fundamental Laws of Nature. The applications of great scientific discoveries almost always slip out of the control of Science itself. This is why technological development almost always contradicts the values instilled by Science: love for Creation and respect for life and human dignity. “Science and Faith are both gifts of God”, said John Paul 11. No Pope has ever before had the courage to put Science and Faith on pedestals of equivalent dignity, and it is out of this truth that the new role of Science is born. And it is this same truth that fathered the “Spirit of Erice”, known in the international scientific community as “The Erice Geist” (a mix of Italian, English and German). It was this “Erice Geist” that brought the greatest Defense intellects from the USA and the USSR to share the same table at Erice’s Seminars on Nuclear War. Thus it seems worthwhile to ask ourselves what happened at Erice 40 years ago. To understand what happened at Erice from 1963 on, it is first necessary to jump back nine hundred years in time. When the first University was founded nine hundred years ago in Bologna, the impetus came from a source that has still not run dry, even today. Quite the contrary. To learn the origins of the latest inventions and discoveries straight from the mouths of the inventors and discoverers themselves ... It was this possibility that pushed a group of well-educated men to establish the first University. In that era, the medical and juridical sciences were the centre of attention. To learn of the latest findings, one had to wait for the books to be drafted. The time necessary: ten years. But now books can be printed in a week. Why then should we insist on seeking the “living voice” of those who discover and invent?

28

29

Victor F. Weisskopf with Antonino Zichichi at CERN, in garden (1960).

30 While the time required to publish a volume has been reduced, our body of knowledge has expanded at an overwhelming pace. What we have learned from Galilei's time up to today is greater than everything that happened during the ten thousand years that separates us from the dawn of civilisation. And what has become of that institution called the University? Slowly and quietly it had to absorb the enormous growth of knowledge. In all fields. So, from the propulsive centre of new knowledge, it became a place of propaedeutic formation. Bringing young scholars to the threshold of new cognition, enabling them to understand what is being done in the most advanced sectors of the different disciplines through which human knowledge is articulated: that is the work of today's University. And it is not trivial work. How should we present the latest inventions and discoveries? By talking about who did them? How they were done? How the conclusions were reached? When a student opens a university text, he almost always gets the impression that the topic of study is a closed chapter. He will rarely find the space to discuss and comprehend what the open problems are in that field. Nevertheless, all fields have such problems to resolve. The expansion of human knowledge has brought university teaching to a temtory that is completely different from where it started out. Nine hundred years ago, a welleducated person could be versed in several different disciplines to their full depth. Today, the discipline of physics alone corresponds to an immense world of knowledge. There are molecular physics, atomic physics, and nuclear and subnuclear physics, to mention only a few of the largest subdivisions in the science of physics. And even if we focus on subnuclear physics alone, we find that there are at least ten recognized specialities within this field.

31

Victor F. Weisskopf, Sidney D. Drell and Antonino Zichichi (Erice, 26 May 1963).

32 In mathematics there are hundreds of sectors, each of great size and interest. Nothing changes if we shift from so-called pure Science to applied Science. To speak of medicine is to give one name to a thousand sectors. So what happens to a young student who wants to know the latest in the sector that is most fascinating to him? A single University might have, at best, only a couple of first-order superstars, and they alone certainly cannot cover all the fields of human knowledge. It is possible to locate the specialists that work on the cutting edge in any particular sector, but it would be an impossible undertaking to seek to learn directly from all of them. You would have to travel all over the world to have the privilege to meet with them and to sit in on their classes. At Erice, anyone who participates in the courses of a particular School - the oldest is that of subnuclear physics - is called a 'student'. In reality, this usually involves young scholars who have successfully completed their university studies and who come to Erice to find out what the new problems are. This happens in all fields, which are too many to enumerate here. It suffices to say that there are over one hundred schools in existence. But what distinguishes Erice the most is the spirit that animates all participants, both students and docents. The primary objective is to learn. No diplomas or degrees of any type are given out. As it was nine hundred years ago. The student listens to the lesson and then, after a break for lunch, the fun part begins. The student can ask any question of the professor. Even the most banal - it will not be punished. It is in everyone's interest to know the thoughts of young brains upon their exposure to scientific findings about which they had, presumably, already imagined many details and specifics, but rarely the same ones that are mixing around in the head of the docent. For a single problem, there are many different approaches. This is the whole point of discussion groups. When a group of scientists gathers to address themes of great scientific novelty, almost anything can happen. Once the Scientific Director of the Zurich branch of IBM came to this School. On his return to Zurich, he resigned from his directorship in order to dedicate himself to an idea that came to him during the courses at Erice. That idea led him to discover high-temperature superconductivity: he was awarded with the Nobel Prize. We are talking about Alex Muller. This is one example of how new ideas can be born at Erice.

33

The father of the Theorem of Time, Professor Eugene W i p e r (on the left in the photo) and Professor Paul Dirac (on the right in the photo), father of the equation which brought to Antimatter, with Antonino Zichichi.

34 The example cited refers to pure scientific research, even if the applications of high-temperature Superconductivity will be of enormous interest for the transport of electric energy and thousands of other activities. The idea of greatest value to come out of Erice, over the course of long years ridden by oft-ignored conflicts involving many countries, is that of the Manifesto that has been self-declared by more than ten thousand scientists from one hundred and fifteen nations. The mission of that Manifesto is the fight against secret laboratories. There will come a day when anyone who does scientific-technological research in great secrecy will be indicted for crimes against Humanity. Opening the doors of scientific laboratories, whatever type of research this action might unveil, would not only provide new impetus to scientific research in all fields of knowledge. It would also derail the insane spiral of the arms race that today, after the fall of the Berlin Wall, has no further reason to exist. Maybe it seems utopian to think that it would ever be possible to root out the secrets of the scientific-techno-military laboratories. One thing, however, is certain. If we fail to do so, sooner or later the planet is destined to go up in smoke. The project of establishing a World Lab that is open to the best intellects, without racial, ideological, political, religious or geographical (East, West, North, South) barriers, is the fruit of a promise that the scientific community - led by Erice - has made for the sake of all those who love peace not only as a word, but also as something that they wish to construct day by day out of facts. As mentioned in the beginning, the scientists of Erice have given life to a new way of conceiving international scientific collaboration: without secrets and without frontiers. This is the Spirit of Erice. As an indispensable part of this collaboration, the Voluntary Scientific Service has the objective of developing all the poor countries (Southern) that are far below the scientific and technological levels of today's industrialised countries (Northern). The Voluntary Scientific Service has leave to realise projects that would require enormous sums of money if it were not able to count on the work offered by thousands of scientists and specialists who ask nothing in terms of stipends or compensation for the work they put in. This voluntarism touches all levels, up to the highest. In fact, contributors to our projects include protagonists of global prestige from Science, Technology and Medicine, among which are many Nobel Laureates.

35

The memorable session when the putsch in Moscow destroyed Gorbachev’s attempt to bring the Soviet Union adiabatically towards democracy. All these events are closely connected with the activities at the EMCSC, with the World Federation of Scientists as the main point of reference for all problems. For example, when the putsch took place in Moscow, the Soviet scientists present in Erice received an ultimatum to return home immediately. Most of them were with members of their family and I vividly recall their terror over the possibility of seeing their common nightmare materialise, the return of a Stalinist-type dictatorship in their country. I sent a telegram to Moscow asking for confmation of the order received by my colleagues in Erice. According to official news, the new government wanted to maintain international collaboration. An order to go back was in contradiction with official statements by the new Soviet government and would have produced serious consequences in the international scientific community. That telegram allowed the USSR scientists present in Erice with their families not to immediately obey the peremptory order received. Fortunately the putsch was quickly over, and the figure above shows a picture celebrating the end of the terrible hours, when we all were convinced that the world was going to be confronted with another long period of cold war. The putsch was really a terrible surprise. In fact, before the destruction of the Berlin Wall, the scientific community participating in the Erice Seminars was optimistic enough to start considering the problems that the planet would have to face once the East-West confrontation was over. This is how the first studies on the Planetary Emergencies started.

36 The results obtained thanks to the Voluntary Scientific Service are born of the Spirit of Erice and demonstrate the importance of our promise as scientists from the industrialised countries (North) to create a scientific solidarity towards the states who are needy in every respect (South). To overcome the gap that grows bigger every year between the poor countries (South) and the rich (North), it is not enough to offer food and medicine. The poor countries (South) also need to learn how to approach and resolve with their own intellectual energy - the problems that inhibit their own development. The rich countries (North) must help them, not with wasted economic energy invested in useless projects, but intellectually and materially with concrete projects whose precise objectives have been elaborated by the scientific community in close collaboration with the best intellectual energy of the needy states themselves. Without the groundwork that the scientific community of Erice was able to establish over forty years of activity, NorthSouth relations would probably be fixed on a collision course. It is the Spirit of Erice that allows us to hope that it may be possible to avoid this. The Centre for Scientific Culture “Ettore Majorana” is neither an Academy nor a University like those familiar to everyone. It is an Institution born in the heart of the Frontiers of Science through the work of Bell, Blackett, Rabi, Weisskopf and the writer himself. We are talking about exponents of Science who will be remembered in the History of Physics of the 20th century. Patrick M.S. Blackett, Nobel Prize winner, Lord and Grand Admiral of the British Navy, discovered the first example of simultaneously produced “electron-antielectron”. In his Laboratory were discovered the first “strange particles”, so called because no-one had predicted or foreseen them. These particles would open up a new frontier in the Subnuclear Universe. Isidor I. Rabi, discoverer of the effect that bears his name, was awarded the Nobel for this; to him we owe the creation of the prestigious School of Physics of the University of Columbia in New York, and of the Scientific Committee of NATO: an enterprise of formidable originality in that it linked a military structure - with the end of defending Europe from the danger of invasion by the USSR - to the Science of free and democratic countries. It was the Laboratory of Columbia University in New York that brought in Enrico Fermi when he was unfortunately required to leave Italy because of racist laws.

37

8 May 1993, Professor Zichichi delivers to the Holy Father - on behalf of the ten thousand scientists of Erice - his welcome address.

38 Victor F. Weisskopf is a mythic figure of European Science. I was, with John Bell, at the beginning of my scientific career when Europe took its first steps towards building a structure that was capable of competing with the gigantic USA. This structure came to be called CERN (European Nuclear Research Center) and is located in Geneva. The mandate of this structure as desired by Rabi, Blackett and Niels Bohr (one of the founding fathers of Quantum Physics) was to evade the flight (the real one) of intellectuals towards the United States of America. CERN, endowed with the most advanced technological machines, was a necessary but insufficient condition for creating a global pole of attraction for the generations of European physicists who were already travelling outside of their home countries. In addition to its technological structure, CERN needed a leader. It would have to be a great scientist, an exceptional master capable of sparking new interests. Weisskopf was the first physicist in the world to calculate the “virtual” effects, in those days called the “polarisation of the vacuum”. Effects that are now the daily bread on the Frontiers of Physics. We would never have been able to reach the Supenvorld frontier if we had not been able to introduce “virtual” effects into the study of Galilean reality. Weisskopf led CERN to the centre of global scientific attention. John Bell, of my generation, became famous for discovering how to resolve the “paradox of Einstein-Podolsky and Rosen”, abbreviated as “The EPR paradox”. These giants of Galilean Science of the 20th century signed on the 8th of May, 1962, in Geneva, the constitutive act of the Foundation and Centre for Scientific Culture “Ettore Majorana”. And so was born the so-called “Erice Centre” with its intent to give new meaning to Science and its culture. Science, said Fermi, enters into society through its applications, not based on the merit of its values. This is why it is necessary to distinguish scientific culture from its vulgarisation. The Erice Centre has demonstrated how it is possible for the values of science to enter into the culture of our times. On this subject, we need to overcome the paradox that has led us to the vulgarisation called “scientific”, which does not distinguish Science from Technology and has never had the courage to denounce political and economic violence. Because it did not denounce the actual roots of the arms race and the ravages of industrialisation, the greater public was exposed to the thesis that it was scientific progress itself, along with its founding fathers, that was responsible for a planet full of bombs and 53 planetary emergencies.

39 eETTORE W O R A N A s CENTRE FOR SCIENTIFIC CULTURE

Erice Statement It is unprecedented in human history that mankind has accumulateds u c h a m i l i y power to destroy. at once,all centres of civilizationin the world and to affect some vital properties of the planet.

The dnnger of a nuclear holocaust is not the unavoidable consequence of the great development of pure Sciena. In fact, Science is the study of the Fundamental Laws of Nature. Technology is the study. of how the power of

Here are our proposals:

1. Scientists who wish to devote all of their time, fully, to study theoretically or experimentally the basic laws of Nature. shouldin nowesufferfor thisfree choice, to do only pun Science. 1. All Governmentsshddmduevery effort to redua or eliminate nstrictions on the free flow of information,ideas and people. Such restrictions add to suspicion and animosity in the world.

manldndcanbeincreased.

3.

Technology can k for peace and for war. ’Ihe choice &tween peace and waris notascientific choice. It is a cultural one: the culiure of love produces peaceful technology. The culture of hnrred produces inshuments of war. Love and hatred have existed forever. In the bronv and iron ages, notoriously pre-scientiftc. mankind inventedandbuiltmkforpaandinsuuments of war. In the so called ’modern era” it is imperative that culture of love wins.

4.

An e n o m u s number of scientists share their

AII Governmentishouldmakeeveryeffort to reduce secrecy in the technology of defensc.The practice of secrecy generates hatred and distrust. To start a ban for military secncywillcreatcgsfabiliiy than offend by deterrence done.

AU Governments should continue their action to prevent the acquisitionof nuclear weapons hy additional nations or nonnational groups.

5 . All Govanmentsshould makeevcryefforI to reduce their nuclearweaponsstodrpiles.

t i n s between pure SdEncersearchand military applications. This is a fundamental sourn for the arms race.

6. AU Govemmmts shouldmakcevery effort to reduce the causes of insecurity of nonnuclear powm.

It is necessary thata new trend develops. inside thescimtificwmmunityommunityandonanintcmationa basis.

7.

It is of vital impoltance to identify the basic factors needed to start an effective process to protect human life and culture from a third and unprscdwrtcd catastrophicwar.To acwrnplish thisitkneccssarytochmgethepccmovement fmm a uniiawal action to a mtly international one involving proposals based on mutual and m e undemandmg.

Conclusion

All Govemmnu shouldmake evcry effort to ban all types of nudear tests in w a ~

technology.

Thosescientists-inthe EastandintheWest who agree with this &rice Statemenb, engage themselves morally to do everything possible inordatomaLethenewfrcnd,outlkd in the p e n t document,komeeffectivc all the world over and as s w n as possible.

-

This Statement was written in ERICE, August 1982. by Paul A.M.DlRAC. Piow ICAPTZA and Antonino ZICHICHI. During the COUM of the thrce years (1982 1985) it has been signed by Tw THOUSAND scientists, the world over.

-

The Erice Statement.

40 So phrases like “father of the atomic bomb” and “father of thc H-bomb” were coined, but without mentioning that the true fathers of these two devices were, respectively, Hitler and Stalin. It was they who gave life to the secret projects for those bombs. It is with the Erice Manifesto that justice was brought to bear on these cultural delusions, a justice that would be realised in 1989 with the collapse of the Berlin Wall. And it was always the Erice Centre that gave the example of the role of Science in confronting and resolving the problems that afflict this marvellous space ship in its voyage around the Sun. At Erice, in fact, will be founded the first nucleus of a new Laboratory with the mandate of studying Planetary Emergencies; not only the two most famous (the Greenhouse Effect and the Hole in the Ozone), but all 53. The new Laboratory is called ILSEAT (International Laboratory for Science Engineering and Advanced Technology) and has been inserted by the Governor of Sicily - Hon. Salvatore Cuffaro - into his government’sprogram. The international scientific community, grateful for the diligence that exponents like those cited - Bell, Blackett, Rabi, Weisskopf - and hundreds of other prestigious figures of Science have exhibited, has welcomed the enthusiastic interest of Governor Cuffaro for this new scientific-technological reality that is rooted in 40 years of activity at Erice. This, however, concerns the future.

THE ACADEMIA EUROPAEA

SIR ARNOLD BURGEN Downing College, The University of Cambridge, UK The creation of the Academia Europaea arose out of a suggestion made at a meeting of European Ministers of Science in 1985 that there was the need of a European Academy of Science. The proposal was developed through meetings at the Royal Society in London. These meetings led to meetings of senior European Scientists and to the creation of the Academia Europaea which held its Foundation Meeting in Cambridge in 1988. The core idea was that closer cooperation in Europe meant more than political and economic arrangements; there needed to be understanding and appreciation of the historical and social differences that focus national attitudes and that there was much to gain in bringing scholars together who might then learn to act in concert rather than in isolation or rivalry. It was agreed that the Academia should cover the whole of knowledge and include the whole of geographical Europe. These proposals need further clarification. At the time of the Academia’s foundation, the European Union represented only some of the countries of Western Europe and excluded those countries in Europe that were still within the Soviet pale and that later were undertaking reorganisation after the disappearance of Soviet control. Yet the scholars of these countries needed especially to be free to become members of any new Academy, which was to include the area that could be considered as sharing the Western heritage of ideas and culture. These features were, of course, not exclusive, having spread to the Americas and elsewhere, but could be contrasted with the cultures of the Middle East and Far East which were rising in importance. In most countries of Europe some version of a National Academy existed with varying degrees of competence, ranging from ones that were little more than social clubs to those that had control of a major area of national activity in the humanities and the natural sciences. For scholars from all these countries it was anticipated that the new Academy would provide wider horizons. The past century has been a period of unparalleled growth in knowledge in all areas but particularly in the natural sciences. The result has been both a growth in specialisation and compartmentation of new knowledge, but also in the formation of new subjects that broke away from their original affiliations and left their parent subject emasculated. In some cases, a great new idea or technology, such as molecular genetics or information technology, has drawn together contributors from a wide range of disciplines, but often at the price of incomprehensibility for those not in the know. Despite this there has been a general feeling that there were great dangers in new developments that occurred out of context, notably new developments that might affect the environment or raise serious problems for the future of mankind. These questions could best be dealt with by a program of cross-disciplinary contact and discussion. This then was the background against which the Academia Europaea was created and we now need to examine how it has tried to respond to these ideals and the problems encountered in trying to do so. The Academia now has over 2000 members elected from

41

42

across Europe and also has some 100 foreign members, most of whom have close connections with Europe. There are no quotas for different countries, but members are elected on their merits, indeed the quality can be judged by the fact that nearly all European Nobel Prize winners are members; the size of the Academia is probably too small and there are many fine scholars who are not yet members, but a balance needs to be found between inclusiveness and the unwieldiness of excessive size. The Academia has held its annual conferences at locations in 14 countries (London, Strasbourg, Heidelberg, Budapest, Uppsala, Parma, Krakow, Barcelona, Gent, Basel, Copenhagen, Prague, Rotterdam, Lisbon and will be held this year in Graz). The theme of these meeting has always cut across disciplines; examples are "The impact of modem biology on the politics, culture and economy in Europe' (1998), "The sea in the Culture of Europe (1999), Concepts of Time (2000), "Risks" (2002), and "What makes us Human?"(2003). A problem that affects a European academy more than a National one is the ease of access of members to meetings. Whereas for a National academy, the distances that members need to travel to attend meetings may be relatively short, for the attendance at meetings of a European academy, the distances are relatively large and this has meant there was a preponderance of members from the local area where any Annual meeting was held. In 1999 the practice was introduced of inviting a group of young scholars from the host country to be the guests of the Academia, thus preventing it being only a matter of interest to older well-established scholars; this has proved to be a popular innovation. A feature of the Annual Meeting has been a keynote lecture (Erasmus Lecture) by a distinguished scholar covering such topics as "Can there be a European Law? (Emst Mestmacker), National identity and the formation of States (Alan Touraine), Power and insecurity in Europe (Lawrence Freedman) and Language and the evolution of the Human mind (Hubert Markl). Some of the difficulties of communicating across Europe can be overcome by printed publications and the European Review was designed with this in mind. It is a quarterly publication, whose aim is that the spread of the subject in every issue should be such, that there should be at least one article that appeals to the diversity of its readers, i.e., those who are not too narrow in their reading! This is not an easy objective to achieve, but it appears not to have missed the mark too often. The Review features what it terms Focuses in which a topic is explored by several authors; recent ones have been on "Quality of life for the Elderly","Risk", "China, Tradition and Modernity", "Japan and Europe, "Building social cohesions", "The future of Universities", "The Theatre" and a current one is on "History and memory" recounting how the population of various countries regard their conduct during World War I1 seen from a fifty year later perspective. The Academia has undertaken a series of special studies notably in the field of education, an area that is in a condition of stressful evolution everywhere in Europe, the old certainties being overturned by the desire to educate as many people as possible to a high level. The most recent publication is "Excellence in higher education", published this year, the result of a conference held jointly with the Wenner-Gren Foundation. Other themes have been "Psychosocial studies in Young People (1995)", "The idea of Progress"

43 (1 997), “Growing up with Science” (1997), and “The impact of electronic publishing on the academic community” (1998). In 1993 the Academia instituted a programme of Prizes to young scholars to aid the development of science and scholarship in Russia. This involves the award of twenty-five prizes each year and has gained support from the Soros Foundation, the Rayne Foundation, Amersham International, the International Science Foundation and others. It is one of the most successful activities that the Academia has initiated. These are some of the achievements of the Academia Europaea to date; there is feeling that more could have been achieved. What has inhibited a greater range of developments and impact? Two major constraints have been felt. The first is finance. It is much more costly to support a Europe-wide activity than one confined to a single country and yet it is very much more difficult to achieve financial support for an organisation that is European. It simply does not offer the local and political attractions to it support from governments that National academies can command, nor does it attract most National Foundations; we can be very grateful that some Foundations have been exceptions to this generalisation and have been such warm supporters. It would seem obvious that the European Commission should welcome such an organisation contributing so effectively to a European spirit in scholarship, but in fact its statutes have prevented its giving more than support for speakers at some of the meetings. The financial situation remains at present a serious brake on the development of new activities. The second restraint is related to the very broad perspective of the Academia. For instance, while the breadth and quality of the European Review is applauded, this puts it very low on the priorities of University and other libraries that are under intense pressure to subscribe to specialised publications which are appearing in ever increasing numbers, and in consequence its circulation is unduly restricted. It takes time for a new academic activity to make its mark on the international scene, and by the standards of the other academies represented at this meeting, the Academia Europaea is hardly into childhood! However, the time is ripe for an increase in its influence in Europe, notably through new activities now in preparation. There are so many instances in the modern world where a balanced judgement is required between interests that press their case without regard for opposing views and particularly where sound judgement is distorted by populist or political pressures; the Academia is in the position of being able to mobilise experts from across Europe to provide a balanced and well argued evaluation of the total picture.

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2.

CLIMATE: GLOBAL WARMING

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CLIMATE CHANGE AND THE COSMIC RAY CONNECTION NIR J. SHAVIV Racah Institute of Physics, Hebrew University of Jerusalem, Israel ABSTRACT We review the evidence linking cosmic ray flux (CRF) variations to global climate change. In particular, we summarize recent results demonstrating that the long-term CRF variability associated with galactic spiral arm passages is the dominant climate driver over geological time scales. This can be concluded from the large correlation apparent between the reconstructed CRF history and the geologically reconstructed temperature record, and the lack of any correlation with the amount of atmospheric C02. The result can be used to quantify the CRF/temperature link and place an upper limit on the atmospheric response to COz variations. In turn,we show that this can be used to resolve the faint sun paradox and understand the origin of the global warming observed over the past century. INTRODUCTION - THE ALLEGED COSMIC RAY FLUX-CLIMATE LINK Accumulating evidence suggests that solar activity is responsible for at least some climate variability. This is indicated by the numerous correlations apparent between solar activity and either direct climatic variables or indirect climate proxies over time scales ranging from days to millennia (e.g., Herschel 1796, Labitzke and van Loon 1992, Eddy 1976, Friis-Cristensen & Lassen 1991, Soon et al. 1996, Soon et al. 2000, Beer et al. 2000, Hodell et al. 2001, Neff et al. 2001). It is therefore hard at this point to argue against any causal link between solar activity and climate on Earth. Nevertheless, the above correlations do not indicate which one of several possible pathways is actually responsible for the above correlations, with probably more than one mechanism at work. The most obvious link would be through direct changes in solar luminosity. However, the climatic variability attributable to solar activity is a few times larger than could be inferred from the 0.1% typical change observed in the solar irradiance (Beer et al, 2000, Soon et al. 2000). Namely, the variability in the thermal flux itself appears to be insufficient to explain the climate variations observed. Two possible pathways were suggested through which solar activity could be amplified and more effectively generate climate variations. First, if the global climate is sensitive to the amount of tropospheric ionization, it should be sensitive to solar activity as well. This is because the solar wind modulates the CRF, and with it, the amount of tropospheric ionization (Ney 1959). A second possibility includes the large UV flux variations. Since this flux is the primary source of heat in the stratosphere, it could affect, for example, the Hadley circulation (Haigh 1996). Correlations relating CRF modulations to climate on Earth exist on two time scales. Over the solar cycle, the solar wind strength varies considerably and, as a result, the amount of tropospheric ionization changes by typically 5%-10%. Svensmark (1998, 2000) and also Palle-Bag0 & Butler (2000) demonstrated that the variations over two decades in the amount of low altitude cloud cover nicely correlates with the CRF

47

48 reachipg Earth. Both signals, of the cloud cover and the CRF, lag by typically half a year behind other solar activity indices. This implies that it is more likely that the cloud cover is directly related to the CRF and indirectly to solar activity, than directly to solar activity. The reason the CRF lags behind solar activity to begin with is because it takes a few months for the solar wind to reach the heliopause and several months for the cosmic rays (CRs) to diffuse from the heliopause to Earth. Over the short time scale of days, various correlations relate CRF variations during Forbush events to various climatic variables. These events are marked by a sudden reduction in the CRF and a gradual increase over typically a 10-day period. Tinsley & Dean (1991) have shown that the Vorticity Area Index over Oceans is correlated with Forbush decreases. Similarly, Pudovkin & Veretenenko (1995) reported a cloud cover decrease (in latitudes of 60N-64N, where it was measured) synchronized with Forbush events. Later, a link between Forbush decreases and rainfall has also been claimed. Stozhkov et al. (1995) found an average 30% drop in rainfall in the initial day of a Forbush event over 47 events recorded during 36 years in 50 meteorological stations in Brazil (statistically significant to 30). While in Antarctica, Egorova et al. (2000) found that on the first day after a Forbush event, the temperature in Vostok station dramatically increases by an average of 10°K. And last, Todd & Kniveton (2002) have recently shown that Forbush decreases are associated with global decreases in cloud cover. Since Forbush events are relatively short, they can be more easily used to separate a CRFklimate effect from other possibilities. The reason is that over the time scale of a few days, there is significantly less correlation between CRF variability and other solar activity indices, such as UV or protons. And indeed, Tinsley & Dean (1991) have shown that the correlation they obtained completely disappears when the VAI is compared with UV changes. Similarly, Egorova et al. (2000) have shown that there is no measurable signal in sync with solar proton events. Moreover, a climatic correlation with Forbush events cannot arise from hypersensitivity to U V , since the latter is absorbed in the stratosphere, which cannot significantly influence tropospheric weather on the time scale of days. Given the above evidence, it is therefore quite reasonable to claim that cosmic rays affect the global climate and the link is most likely through control of the tropospheric ionization, which modifies the cloud formation process. Although the actual link is not critical to the rest of our discussion, it is interesting that several new results indeed point to the validity of this mechanism. Two particularly interesting results should be mentioned. First, Hamson & Aplin (2001) found experimentally that the formation of cloud condensation nuclei (CCN) is correlated with natural variability in the CRF (e.g., due to statistical variability of CR air showers). In other words, this link is more than hypothetical. Second, using an advanced particle microphysics model, Yu (2002) discovered that a scenario in which the formation of CCN depends on tropospheric ionization, explains several interesting observations. Yu found that at low ionization rates, CCN formation increases with increasing ionization rates. This is because the system i s “ionization limited”. However, at large enough ionization rates, the formation of CCN decreases. This result, which at first might seem counter-intuitive, stems from the fact that if the ionization rate is large enough, condensation nuclei cannot grow quickly enough after they form, without discharging themselves through ion-ion recombination. The net result is that increasing the ionization

49

rate increases the CCN density at low altitudes, but it reduces the CCN density at high altitudes. This result is interesting as it implies that global warming induced by solar activity modulating the CRF should increase the surface temperature without changing the average tropospheric temperature by much. This offers an elegant solution as to why global warming in the past few decades was observed primarily near the surface but not by satellites and only marginally by balloons, since greenhouse gases are expected to heat the tropopause more uniformly. LONG TERM CRF VARIATIONS AND THE GEOLOGICAL RECORD An altogether independent piece of evidence linking CRF variability to temperature on Earth is the circumstantial link apparent between long-term CRF variations and geological reconstructions of climate on Earth. Long-term CRF variations arise because the solar system changes its galactic neighborhood as it revolves around the galaxy. When nearby supernova events are more numerous, more cosmic rays are accelerated in our galactic vicinity and the CRF reaching Earth is respectively higher. Moreover, studies of spiral galaxies like our own reveal that supemovae (SNe) occur predominantly in the vicinity of the galactic spiral arms. This is unsurprising considering that spiral arms harbor most of the star formation activity, and that massive stars live relatively short lives so that they are born and die within the spiral arm vicinity. The net result is that the CRF near spiral arms can be significantly higher, by a factor of a few, over the flux between the arms (e.g., Shaviv 2002b and references therein). Using astronomical data, the difference between the solar system’s angular velocity Qsun around the galaxy and the spiral arm pattern speed SZ, is found to be R,,,R,=ll.l+2.0 (km/s)/kpc (Shaviv 2002b). Since the Milky Way has 4 spiral arms, this angular velocity difference translates to a spiral arm passage every 1342~24Myr. Thus, the astronomical prediction is that the CRF reaching Earth should vary with the above period. If the CRF/climate link is real, we should see a climatic affect with the above periodicity. Figure 1 plots the predicted spiral arm passages using the astronomical data and the ensuing CRF using a model described in Shaviv (2002a,b). This is then compared with the geological sedimentation evidence for the occurrence of ice age epochs (IAEs) or warm periods (i.e., “icehouses” and “greenhouses”), as summarized by Frakes et al. (1992) and Crowell (1999). Interestingly, Frakes et al. claim that the geological data is sufficient to claim periodicity. Crowell on the other hand, claims that the data is insufficient to make the claim of periodicity and indeed his epochs occur less regularly. Irrespectively, both records are consistent with each other, but more importantly, they are consistent with the predicted CRF using the astronomical data. The correlation between astronomical and geological data suggests that indeed there is a causal link between galactic geography and climate. It does not point to the actual mechanism of the physical link. A smoking gun, which would point towards the CRF as the culprit, would be any historic record that can be used to reconstruct the CRF and, with it, show that the predicted periodic CRF variations indeed exist and that the

50 CRF varies in concordance with climate variations. Such a historic record exists in the form of exposure ages of Iron meteorites'. Figure 1: The past Eon. Panel A describes past Galactic spiral arms crossings assuming L&-Q=lO.9 (km/s)Apc. Panel B describes the CRF reaching the solar system using a CR dirusion model (Shaviv 2002b). Note that the CRF is predicted to lag behind spiral aim crossings. This is portrayed by the hatched regions, which qualitatively show the predicted occurrences of IAEs, if the CRF required to trigger them is the averagejlux. Arrows mark the middle of the spiral crossing and the expected mid-glaciation point. Panel C qualitatively describes the geologically recorded IAEs-its top ha& as summarized by Crowell (1999), and its bottom ha& as summarized by Frakes et al. (1992). By jne-tuning the observed pattern speed of the arms to best j t the IAEs, an intriguing correlation appears between the IAEs and their prediction. Note that the correlation need not be absolute since additionalfactors may affect the climate. Otherfactors that should be considered and noted in the graph are: (1) The mid-Mesozoic glaciations are signzjkantb less extensive than others. (2) It is unclear to what extent the period around 700 Myr BP was warmer than the IAEs before or since. (3) Thejrst IAE of the Neo-Proterozoic (if indeed distinct) is very uncertain. (4) Since Norma's crossing is an extrapolation@om smaller galactic radii, its location is uncertain. r f the arm's structure at smaller radii is indeed direrent (Shaviv ZOOZb), its preferred location will lag by about 20Myr. Panel D is a 1-2-1 averaged histogram of the 41Kf0K exposure ages of Fe meteorites, which are predicted to cluster around the CRF minima. The cluster-IAE correlationJitrther suggests an extra-terrestrial triggerfor the glaciations.

Using a set of exposure-dated Iron meteorites it is possible to reconstruct the CRF. This is because the CRF is the 'clock' used to exposure-date the meteorites. As a consequence, variations in the CRF translate into distortions in the exposure ages. Using a statistical method described in Shaviv (2002b) these distortions can be used to reconstruct the CRF variations. The principle behind this new method is the fact that during periods with a low CRF, when the exposure age 'clock' ticks slower, many meteorites cluster around these apparent exposure ages. This is because long real time intervals elapse while the exposure clock measures a short interval only. Thus, the prediction is that a histogram of the exposure ages of iron meteorites will show clustering around epochs with a lower CRF, when a warmer climate is expected. This clustering is indeed apparent in the data, (see figure 1) providing an independent link between CRF variations and climate variations on Earth. The climate history used in the above comparison was a qualitative reconstruction using geological sedimentation records. It could only indicate the existence of cold or

' Chondrites are not useful for this purpose, since their typical lifetime is short.

51 warm periods. More information would be learned if we could compare the CRF variations to a quantitative paleoclimatic record. At the least, it would allow the quantification of the CRF-climate link. isotope ratio measurements of fossils from tropical Using thousands of '80/'60 oceans, Veizer et al. (2000) reconstructed the temperature over the Phanerozoic2. This record was subsequently used for the quantitative comparison between CRF variations and climate (Shaviv & Veizer 2003). The results are graphically depicted in figure 2, where it is apparent that the reconstructed CRF history, using the extra-terrestrial record of meteorites, has a remarkable correlation with temperature. Since the residual in the fit bears no resemblance to the variation of atmospheric C02, an upper limit to its effect can be deduced. Using a statistical analysis, the following conclusions can be reached: CRF is responsible for 75% of the long-term (>50 M y ) variance in the 1) tropical temperature. Thus, the CRF is by f a r the most dominant climate driver over long time scales. An upper limit on the effect of C02 can be placed. At lo, the upper limit on 2) the temperature increase resulting from a doubled amount of atmospheric C02 is about 0.9"C (it is about 1.5"C and 2.6"C at the 90% and 99% confidence levels). This can be translated into a limit on the global temperature response of radiative forcing. As compared with the response of a hypothetical black body, Earth, the upper limit on the response is h <0.75 (or h 4 . 2 or 2.2 respectively). Namely, it is more likely that Earth has negative feedbacks that stabilize its climate response more than the behavior of a black body. Figure 2: Variations in the cosmic rayjlwc (0) and tropical temperature 15 anomaly (AT) over the Phanerozoic. g 1 The upper curves describe the 8 05 reconstructed CRF using iron meteorite exposure age data (Shaviv, hanemzoic Temperature ' 2002b). The thick solid line depicts 2 the nominal CRF, while the shading delineates the allowed error range. The two dashed curves are additional CRF reconstructions that fit within 4 the acceptable range. The shortdashed curve describes the nominal -2 CRF reconstruction after its period *. (Cosmic Rays + /meor) was fine-tuned to best fit the low-500 -400 -300 -200 -100 0 latitude temperature anomaly (i.e., it is the 'Solid-line " reconstruction. after the exact CRF periodicity was fine tuned, within the CRF reconstruction error). The bottom long-dashed curve depicts the reconstructed temperature anomaly (AT from Veizer et al. 2000 smoothed with a SO Myr window). The solid line is the predicted AT,,,,,~e~ using the short-dashed curve above, while also allowing a secular, long-term linear contribution. The thin line is the residual. The largest residual is at 250 Myr BP, where only a few measurements o f 8 ' 0 exist due

-

e- ,

2

The Phanerozoic is the last 550 M y from which fossils of multi-cellular life exist.

52 to the dearth of fossils subsequent to the largest extinction event in the Earth s history. The top bars are icehouse periods according to Frakes et al. Figure 3: Plotted are the period and phase of four independent signals, their agreement indicates that the CRF/climate link is highly probable. The phase is defined as the time t,, before present when 150 the cosmic rayflux is largest or the climate is warmest divided by the respective signal period. The four signals are the predicted 3 0 . CRF from astronomical data (using 11100 measurement of the pattern speed of the T I galactic spiral arms and a dij&sion model .-L0 . for the cosmic rays), reconstruction of the L cosmic ray flux in the solar system (using the exposure ages of Iron meteorites), occurrence of ice-age epochs (ice-houses) and warm periods (greenhouses) using 00 geological sedimentation records, and laslyt, the reconstructed tropical sea temperature (using ' 8 ~ / ' 6isotope ~ ratio in fossils).

-

Icehouse-Greenhouse EmkesetaliGaweU

Cosm'cRay fromFeMeteor'ter

-

-

v

0.2

Phase 0.4 = t,JP0.6

0.8

1

Figure 3 is a graphical summary of the above correlations. It depicts the period and phase of the four independent signals, showing their mutual agreement. Two of the signals are extra-terrestrial in nature. One is the predicted CRF variations arising from spiral arm passages as calculated using astronomical data. The other signal is the measured periodic CRF history using Iron meteorites. The two other periodic signals describe climate variations. One is of the coldwarm epochs as apparent from the geological sedimentation record, while the other is the reconstructed tropical temperature. The fact that the four results for the phase and period are in agreement, demonstrates that it is more than a statistical fluke. Moreover, since there are two independent extraterrestrial records and two independent climate records, the result is redundant. Armed with the quantitative relation between CRF variations and temperature change, as well as with the limit on the climatic effects of variations in the amount of atmospheric COz, we can proceed with application of these results. IMPLICATIONS OF THE CRF CLIMATE LINK - THE FAINT SUN PARADOX Standard solar models predict a solar luminosity that gradually increased by about 30% over the past 4.5 billion years. Under the faint sun, Earth should have been frozen solid for most of its existence. Yet, running water is observed to have been present since very early in Earth's history. This enigma is known as the faint sun paradox. The CRFklimate link has the power to significantly extenuate this problem (Shaviv 2003). To reach this conclusion, we should consider that the young sun was rotating faster. As a result, it must have had a higher non-thermal activity and, with it, a stronger solar

53 wind. Since the solar wind slows the flux of galactic CRs, the stronger wind necessarily lowered the CRF reaching Earth. A lower CRF would in turn translate into higher temperatures through the CRF/climate link. Thus, a stronger solar wind should have had a warming effect that acted to compensate the solar dimness. The effect can be quantified. To do so, one can calculate the attenuation effect of an evolving solar wind. The evolution itself can be reconstructed by comparison to the observation of stellar winds of nearby solar-like stars. The slowly increasing CRF and the CFWtemperature relation can then be used to calculate the global temperature and compare it with the effect of the slowly increasing solar luminosity. The results from the detailed analysis (Shaviv 2003) are graphically depicted in figure 4. The crux of the results is the following: a) The increasing solar wind and the ensuing reduction in CRF can explain about two thirds of the temperature increase required to resolve the faint sun paradox. b) The remaining third or so of the discrepancy can be explained with greenhouse warming by modest quantities of atmospheric COz (-0.01 bar), amounts that are consistent with geological constraints. c) Once the Milky Way’s star formation rate is included, the coldest temperatures are predicted to have occurred over the past Eon, and the between 2 and 3 Gyr before present. Interestingly, these are also the only epochs during which Earth experienced glaciations. d) The compensation between solar luminosity increase and CRF decrease is now reaching its end, since the solar wind reduction of the CFG is now only -10%. This implies that solar luminosity increase will now contribute to a slow warming trend over the coming billions of years. Figure 4: Past and future tong term global temperature 40 changes. Model (A) describes the temperature predicted without a CRF-climate effect, 30 with a nominal contribution by C02 (0.01 bar before 3 Gyr, U then exponentially decreasing ::20 afterwards to current levels, e and constant thereafter), and a ED radiative feedback parameter 10 of II =2.2 (which is statistically inconsistent with the long term temperature reconstruction at 0 the 3clevel). Model (C) is the same as model (A), except that II=0.75, which is the nominal Time BP [Gyr] value from temperature-CRFC02 comparison over the Phanerozoic. Model (B) is the same as model (C) except that it assumes a constant CO2 contribution. Model (0)and associated lines are the same as model (C) with the CRF/climate link included using the nominal parameters. The thick dashed line assumes that the CRF reaching the outskirts of the solar system is constant. The thin solid line includes the

Y

54 variations in the Milky W q ’ s star formation rate, while the long dashed line includes the range of variability associated with spiral a m passages. The dotted line denotes the total variability arisingfrom all long-term intrinsic variations in the CRF.

IMPLICATIONS OF THE CRF CLIMATE LINK - UNDERSTANDING GLOBAL WARMING Doubling the amount of atmospheric COz results with a radiative forcing of about 4 W/mz (e.g., IPCC 2001). This is hard to dispute. The big uncertainly in climate dynamics, however, is the global temperature response to this change in the energy budget. For a blackbody Earth, this response is 0.30°K / (W/m2). Earth however does not behave as a black body, and various positive and negative feedbacks act to either amplify or decrease this number by a factor h. Values obtained in global circulation models (GCMs) range between h=2 and 4.5, i.e., positive feedbacks act to significantly amplify the temperature response (e.g., IPCC 2001). There are however debated claims that various negative feedbacks should be considered, yielding a much smaller h of 0.5-1.3 (Lindzen, 2001), or even -0.2 (Ou, 2001). This number was also obtained from analyses of actual temperature variations. For example, from the rather quick return of the global temperature to its “average” after a series of volcanic eruptions, it was deduced that h-0.5 with h>l being inconsistent with the effects of volcanic driving (Lindzen & Giannitsis, 1998). On the other hand, Gregory et al. (2002) find that a lower limit of h=1.3 (at 95% confidence) can be placed by considering the increase in the ocean heat content. Another constraint was obtained by Covey et al. (1996) who compared COZ changes to temperature variations over geological time scales (in particular, the last glacial maximum, the Cretaceous and early Eocene). The authors of this study found that h is consistent with the range of values obtained in GCMs. However, the latter two constraints were obtained while neglecting the possible forcing of the CRF and the non-thermal solar activity. Thus, if CRF/climate link is real, these two constraints are not applicable anymore. In the previous sections, we have seen that once CRF variations are considered over geological time scales, a marked correlation is obtained between CRF as a driver and temperature change. This correlation, combined with the lack of correlation with COz variations, yields h < 0.75 (or h< 1.2 or 2.2 at 90% or 99% confidence level). Thus, ifthe CRFklimate connection is valid, which appears to be the case from the high CRF/AT correlation, we should consider h 0.75 as the most probable value. What does this result imply in the context of global warming? According to the IPCC, the radiative forcing due to anthropogenic emissions since the 1 9 3 0 ’ ~ is~about 1 W/mz (IPCC, 2001). This does not include indirect forcing by the sun (through solar modulation of the CRF or other possible effects). The largest uncertainly in this number is the possible indirect effect of aerosols. For a GCM type climate response of h 2.5, this radiative forcing should have contributed a global warming of about 0.75”K. However, this assumes an equilibrium response. In reality, the oceans have a high heat capacity and it takes centuries for Earth

-

-

We use the 1930’s for comparison, because the high energy CRF data required for comparison is not available before.

5 to reach equilibrium. On the short time scale, only about 2/3’s of this increase should appear (e.g., IPCC 2001). Thus, 1 W/m2 and h 2.5 can explain the 0.4-0.5”K global warming observed since the 1930’s. This is the standard lore. However, the CRF climate link is only consistent with a small value of h. If we take h 0.75, the global warming associated with “standard” contributions is only about 0.23”K in equilibrium, or 0.17”K over short time scales, that is, only about a third of the observed warming appears to arises from human activity and other standard contributions to the radiative forcing (e.g., as mentioned in the IPCC report, 2001). Where do the other 2/3’s come from? By comparing the CRF to temperature change over the phanerozoic, it was obtained that a CRF increase of 1% should translate to a temperature decrease of about 0.10~0.05°K.Over short time scales, the CRF variations are not “intrinsic” but instead arise from solar modulation, which is energy dependant. When trying to predict the temperature increase associated with the increased solar activity over the past century, we should therefore use the CRF energies that are most likely responsible for the apparent climate effect. These energies are those penetrating the troposphere and which can reach low geomagnetic latitudes. This is because cloud microphysics is most likely governed by the low altitude tropospheric ionization rate. Thus, the flux measured at the University of Chicago Neutron Monitor Stations in Haleakala, Hawaii and Huancayo, Peru is probably a fair measurement of the flux affecting the climate. Both stations are at an altitude of about 3km and relatively close to the magnetic equator (rigidity cutoff of 12.9 GeV). Typical variations of about 8% are generally recorded in the above stations between solar minimum and solar maximum. Since neither station was active before the 1950’s, we can use ion chamber data for comparison. Ion chambers record typical variations of 2% over the solar cycle, while the average ion chamber count decreased by 1.O% over the past 70 years. This implies that at energies most likely responsible for the climate effect, the decrease was about 4%. Using the result of Shaviv & Veizer (2003), this translates into a temperature increase of 0.4k0.2”K assuming equilibrium, or more realistically, to about a 0.27*0.13”K increase over the past 70 years. Thus, the result obtained by comparing CRF variations to temperature change over the past 550 Million years first implies that climate has a low response to radiative forcing, such that about a third of the increase should be attributed to anthropogenic gases and other “standard” radiative forcings. Secondly, the CRF-temperature relation implies that about two thirds should be attributed to the increased solar activity, which lowered the CRF reaching the Earth. Together, the observed global warming is consistently explained. Interestingly, this result was already independently reached by other means. Since the observed global warming over the past century was not monotonic-it decreased between the 1940’s and ~O’S,one can fit the global warming to an anthropogenic contribution (which was increasing monotonically) and a solar activity contribution (which also decreased between the 1940’s and 70’s). This was done by Soon et al. (1996), who found that the best fit arises when somewhat less than half of the increase is attributed to an anthropogenic cause, while somewhat more than a half is attributed to solar activity, without specifying the physical link.

-

-

56 SUMMARY Ample evidence links CRF variations to climate change on Earth. A partial list of results is summarized in Table 1. The result by Shaviv & Veizer (2003) is particularly important as it can quantify the CRFhemperature relation and it can be used to place a limit on the climate response to the radiative forcing of C02 variations. It was found that periodic CRF variations arise from galactic spiral arm passages, giving rise to a clear periodic temperature variation over the past 550 Million years. Specifically, the CRF variations can explain about 75% of the total temperature variance observed. Since C02 is expected to have varied over the phanerozoic as well, it should have left a mark in the temperature signal. Since no clear temperature variations arising from C02 variability are apparent, an upper limit to the effect of COz can be placed. Table 1.: Published result Result A correlation between '*o/'~o in stalagmites in a cave in Oman and I4C in the atmosphere (Neff et al. 2001) A correlation between low altitude cloud cover and CRF variations over the solar cycle (Svensmark 2000).

A Correlation between Forbush events and vorticity area index (Tinsley & Dean, 1991)

A Correlation between Forbush decreases in CRF and reduction in global cloud cover (Todd & Kniveton 2001) A Correlation between Spiral Arm passages, reconstructed CRF history using Iron meteorites and ice-age epochs on Earth (Shaviv 2002a.b) A Correlation between the reconstructed CRF

(inkingCRF variations to climatc. Not inclusive. Meaning of the Result By far, the nicest correlation between solar activity (of which I4C is a proxy) and global temperature (to which the 180/160 isotope ratio is sensitive). It implies that a robust link between solar activity and climate should exist. CRF appears to affect climate through modification of the cloud formation process, and it provides a natural link between solar activity, which modulates the CRF, and climate. The lag between both the CRF and cloud cover signals, and solar activity, supports the idea that the soladclimate link is through CRs, as opposed to other solarclimate links. This link is a stronger indication that climate is affected by the CRF. This is because there is a lack of any correlation with solar activity indices. (Namely, it not just a lag between CRF variations and solar activity, as obtained over the solar cycle). This result reaffirms that the CRF/climate link is most likely though the modification of the global cloud cover, and it again supports the role of CRF in the solar/climate link, since no direct correlation was found with solar activity. The result decouples CRF variations from solar variability, since the former are intrinsic. This firmly convicts the CRF as a climate driver. It also shows that the CRF/climate link does not saturate at small CRF variations, and the effect can be large. It also offers a solid explanation for the almost periodic occurrence of ice-age epochs. The correlation between CRF variations and temperature variability quant$es the CRF/climate link, thereby allowing

57

history and temperature predictions using this link. The lack of any correlation with on Earth. (Shaviv & COz variations is used to place an upper limit on the climate between CRF variations and cloud condensation nuclei (Harrison & Aplin 2002 A Cloud microphysics simulation by Yu (2002)

I

This innovative experimental result demonstrates that higher CRF give rise to higher concentrations of cloud condensation nuclei. CRF/ionization/cloud-condensationpicture, which hitherto was almost exclusively theoretical. The numerical simulations by Yu have shown that the formation of cloud condensation nuclei should be affected by the CRF. The detailed predictions explain why low altitude clouds are most sensitive to the CRF and why most of the global warming over the past century was measured 1 near the surface but not in the upper troposphere.

The normalized CRF/temperature relation can be used to explain about two thirds of the faint sun paradox. Because the sun was more active in its youth, its stronger solar wind was responsible for preventing most of the CRF from reaching Earth. Through the CRF/climate effect, this translated into elevated temperatures, which tended to compensate for the effect of the dim sun. The effect can only explain about 2/3s of the discrepancy. The remaining 1/3 can be naturally explained with a modest contribution of atmospheric C02. A second application of the limit on the climatic response to radiative forcing, and the relation between CRF and temperature variations, was to understand the global warming observed over the past century. It was found that the combined astronomicallgeological analysis implies that about two thirds of the global warming over the past century should be attributed to increased solar activity (which reduced the CRF reaching Earth), while only about a third should be attributed to “standard” radiative forcings, arising primarily from anthropogenic activity. This research was supported by the F.I.R.S.T. (Bikura) program of the Israel Science Foundation (grant no. 4048/03). REFERENCES: 1.

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10. Haigh, J.D., Science 272,981 (1996). 11. Harrison, R.G. and K.L. Aplin, J. Atmos. Terr. Phys. 63, 1811 (2001). 12. Herschel, W., Philosophical Transactions of the Royal Society, p. 166 (1796) 13. Hodell, D.A., M. Brenner, J.H. Curtis, J.H. Guilderson, Science 292, 1367 (2001) 14.

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CLIMATE CHANGE EFFECTS ON SPECIES AND BIODIVERSITY A. TOWNSEND PETERSON Natural History Museum and Biodiversity Research Center, The University of Kansas, Lawrence, USA INTRODUCTION: CLIMATE CHANGE AS A REALITY Perusal of recent issues of any number of scientific journals reveals numerous contributions treating climate change ([Anon] 2003, Gong and Shi 2003, Rahmstorf 2003, Rosqvist and Schuber 2003, Steemers 2003). In general, observations indicate dramatic warming trends across recent decades, changes in precipitation, and increasing frequencies of extreme events (Houghton et al. 2001). A broad initiative of modeling climate futures using general circulation models (GCMs) has yielded a rich suite of future-climate projections based on different scenarios of atmospheric composition (Flato et al. 1999, Nakicenovic and Swart 2000, Pope et al. 2002). Both the reality of these changes and their causes have been the subject of considerable controversy. Regarding the former, although some details are debatable, the reality of trends post-1960 is difficult to dispute (Houghton et al. 2001). Regarding the latter, however, the issue is less clear-whether climate change is caused by anthropogenic activities or not has been debated extensively (Laut 2003, Solanki and Krivova 2003), not only in scientific circles, but also in political circles. In general, though, an enormous body of evidence now points towards (1) the observed changes being real long-term trends, and (2) anthropogenic influences in the form of increasing ‘greenhouse gas’ concentrations being the primary cause of the changes (Houghton et al. 2001). For the purposes of this COI 1 ’ 1 d o n , nonetheless, the root causes are less important than that the changes are tak *: )lace-I focus on the implications of changing climates for elements of biodiversity. THEORETICAL EXPECTATIONS FOR BIODIVERSITY Biological diversity (“biodiversity,” for short) exists in a context of climates and landscapes, and species are well-known to respond to climatic factors in their phenology and geographic distributions (Grinnell 1917, 1924, MacArthur 1972, Brown 1995). In general, for geographic phenomena, we can refer to the concept of an ecological niche, defined as the conjunction of conditions within which a species can maintain populations without immigration (Grinnell 1917, 1924)-this concept differs from later versions, which focused more on the role of species in ecosystems (Hutchinson 1957, MacArthur 1972), but offers a clear geographic perspective on species’ ecology and distributions. In brief, the ecological niche serves as one important constraint on species’ geographic potential. Recent work in theoretical ecology and evolution has treated the evolution of ecological niche characters quantitatively, and led to a remarkable convergence of thinking between numerous theoretical ecologists (Brown and Pavlovic 1992, Holt and Gaines 1992, Kawecki and Steams 1993, Kawecki 1995, Holt 1996b, a, Holt and Gomulkiewicz 1996). Because populations existing under conditions outside of a species’

6 0 niche are expected to decline and have greatly reduced fitness, they contribute little to species’ evolutionary dynamics. As a result, stabilizing selection is expected to be strong, producing conservatism in ecological niche characteristics in most situations. Although niches obviously do evolve (or all species would share the same niche!), this prediction suggests that species will frequently not change dramatically in their ecological profiles, particularly over short periods of time (as are important in considerations of climate change). Empirical results relevant to this question are now accumulating as well-in general, they amply confirm theoretical expectations. Tests developed to date include predictivity of the geographic potential of species’ invasions in nonnative areas (Peterson and Vieglais 2001, Peterson In press), predictivity of species’ range shifts during past climatic shifts (Martinez-Meyer 2002), predictivity among sister species pairs (Peterson et al. 1999), and predictivity across phylogeny (Rice et al. In press). In general, and not without exceptions (Peterson and Holt In press), the general prediction of conservatism in species’ ecological niche characteristics is confirmed. Species’ ecological niche characteristics thus constitute long-term, stable constraints on their distributional potential. Given this tight relationship between species’ geography and features of climate, what are theoretical expectations for species’ responses to changing climates? In general, for a population residing in an area with a changing climate, three possible outcomes can be considered (Holt 1990): 1. Track appropriate conditions - Here, dispersal abilities of a population permit invasion of new areas as they become habitable, and populations ‘left behind’ in the previous distributional areas decline towards extirpation. This tracking can be in spatial (range shifts) or temporal (phenological shifts) dimensions. 2. Evolve to meet the new conditions - Here, the population has sufficient genetic variation to permit adaptive evolution of niche characteristics, and populations adjust to changing conditions without range shifts. 3. Go extinct - Failing the two previous options, populations are located at sites with conditions falling outside of their ecological niche envelopes, and populations decline towards zero. These three possibilities represent the range of reactions for species under changing climates, and thus will provide a framework for the rest of this contribution. Indeed, they can be translated into more concrete expectations of species’ responses to climate change: 1. Poleward and upward expansion cf populations - With warming trends, in general, conditions will improve at the poleward and upward (elevationally) limits of species’ geographic distributions. 2. Equator-side and lower-elevation extirpation of populations - With general warming trends, conditions will usually worsen for a species along the equator-side and lower-elevation border of its range. 3. Phenological sh$ts towards earlier timing - For species that emerge, breed, or whatever in spring, after a cold winter period, phenological shifts earlier in the season are expected. For species responding to other suites of factors (e.g., onset of rains), phenological shifts may occur, but are less generalizable as to the form that they will take.

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Extinction in bounded situations - Assuming that niche evolution is relatively uncommon, when species are limited from dispersal, they are expected to go extinct. Particularly frequent will be extinctions in bounded situationsmountaintops, islands, etc., in which no dispersal options exist. These expectations are derived directly from theoretical considerations, and provide a general rubric within which climate change effects on biodiversity can be considered. 4.

OBSERVED EFFECTS ON BIODIVERSITY The scientific literature is replete with examples of observed changes in phenology or distribution of species that are attributed to the effects of climate change (Bethke and Nudds 1995, Parmesan 1996, Allen and Breshears 1998, Inouye et al. 2000, Linderholm 2002, Walther et al. 2002, Beaugrand and Reid 2003, Cresswell and McCleery 2003, Crozier 2003, Inouye et al. 2003, Perfors et al. 2003, Saavedra et al. 2003). Given that species’ distributions are well-known to be fluid and changeable, some caution is merited in interpreting these attributions. Nevertheless, more detailed and controlled metaanalyses have confirmed that a great number of shifts are occurring and that they fit the generalities expected of climate-driven effects on species (Parmesan et al. 1999, Parmesan and Yohe 2003). Regarding the three theoretical expectations listed above, each has seen detailed consideration. Distributional shifts have been documented amply, as have phenological shifts, with species emerging, flowering, or breeding earlier with warming climates (Walther et al. 2002). Although these shifts are far from universal (Peterson 2003b), the overall pattern of changes nevertheless fits the specific climate change-related expectations listed above. Perhaps most interesting, however, are the cases of constraint that are now emerging. For instance, in a particularly well-known case, amphibians in many regions are experiencing catastrophic declines (Pounds and Crump 1994) at least in part attributable to aspects of changing climates. In at least one case (Pounds et al. 1999), these declines have been absolute, leading to the extinction of an amphibian species-this system was bounded, in the sense that the conjunction of forest and cloud layers that had provided the conditions necessary for the species to persist no longer existed. Other systems are now providing less dramatic but even better documented examples, in which evolutionary and/or dispersal capacities are likely to be insufficient to prevent extinctions or broad population losses (Etterson and Shaw 2001, Nadkarni and Solano 2002, Hoffmann et al. 2003, Zacherl et al. 2003). PROJECTED EFFECTS ON BIODIVERSITY Observed effects of climate change on species are fascinating, and provide a key documentation that theoretical expectations are more than just imagination, but rather are the first indications of what will likely prove to be a major concern in coming decades. While these observations are increasingly common, and have fit well with a priori predictions, they nevertheless do not provide the whole picture-if these changes are but thefirst steps, what form will subsequent steps take? That is to say, observed changes do not show us the whole picture of biodiversity consequences of climate change, and as a

6 2 result we must seek other, more anticipatory, means of understanding the dimensions of the challenge. Such anticipatory (predictive) approaches to understanding climate change effects on biodiversity have taken two general paths: modeling ecosystems and natural processes (not directly the focus of this paper), versus modeling individual species via ecological niche modeling (Peterson et al. In press). In the first case, a long evolution of increasingly complex models has produced an impressive literature regarding expected shifts and extents of ecosystems around the world (Prentice and Webb 1989, Neilson et al. 1992, Melillo et al. 1996, Neilson et al. 1998, Tian et al. 1998). Biogeography models evolved from statistically-based climate-vegetation classification approaches to process-based biome models (Box 1981). Newer ecosystemhiome models are increasingly processbased, rather than just based on statistical correlations in empirical data (Neilson et al. 1992, Prentice et al. 1992, Woodward et al. 1998). Most recently, however? a generation of dynamic global vegetation models has emerged (Prentice and Webb 1989), in which process simulation is even more biologically realistic, and results have been shown to be increasingly predictive of current patterns of ecosystem distribution. This direction of research, however, does not maintain a direct connection to individual species (the base elements of biodiversity), and so will not be explored fkther in this contribution. The second approach to anticipating climate change effects focuses on individual species’ ecological needs (modeling the ecological niche), and then uses the previous results demonstrating ecological niche conservatism to project ecological niche characteristics forward onto fiture climatic conditions. Ecological niches are modeled using a variety of tools, including statistical approaches (Huntley et al. 1995) and machine-learning approaches (Peterson et al. 2001), among others. While early implementations simply used imagined scenarios (e.g., +I% temperature, -5% precipitation) as scenarios (Carey and Brown 1994), recent work has used specific GCM scenarios as basis for more detailed projections (Peterson et al. 2001, Bakkenes et al. 2002, Berry et al. 2002, Midgely et al. 2002, Peterson et al. 2002, Midgley et al. 2003, Peterson 2003a, Siqueira and Peterson 2003). These species-specific approaches have now become sufficiently extensive as to provide some first indications of generalities that can be expected of climate change effects on biodiversity: 1. Extinctions - Species-specific models suggest that numbers of species likely to go extinct as a direct consequence of climate change effects vary dramatically among regions and among taxa, and can range from almost nil up to 40-50% in worst cases (Siqueira and Peterson 2003). 2. Idiosyncratic responses - Although on average future projections of species’ distributions obey the tendencies described above, many exceptions exist, emphasizing that species’ responses to climate change will be idiosyncratic and individualistic (Peterson 2003a). 3. Montane versus flatlands effects - A trend that appears to be emerging, although data are preliminary, is that montane systems will be considerably better buffered against horizontal climate change consequences than will be flatlands regions (Peterson 2003a). For instance, the Great Plains in the United States and the Cerrado in Brazil are both predicted to see rather severe climate change consequences for species (Peterson 2003a, Siqueira and Peterson

63 2003), whereas Mexico and the Rocky Mountains in the United States are expected to see less serious consequences (Peterson et al. 2002, Peterson 2003a). 4. Extinctions versus rearrangements - Although several major climate change impact surveys have indicated that numbers of species likely to go extinct as a direct result of climate change effects may prove relatively low, most species are expected to retract and expand their distributions here and there across their distributions, which will create many new ecological situationscommunities with unknown characteristics and behavior. 5 . Unknown environmental conditions - A major unknown in the implementation of these species-level models is how to treat new environmental combinations that emerge in future climate scenarios. This question is clearly related in many ways to the question of species’ adaptability. In sum, single-species modeling has now been implemented for sufficient regions and taxa as to permit a few first generalizations. Much more work, of course, remains to be done in order to provide a predictive view of likely future effects of climate change on biodiversity. SYNTHESIS Biodiversity depends critically on the distribution and configuration of climates across the Earth’s surface. Whereas climate change as a result of anthropogenic greenhouse gas emissions may be debatable, that climates are reorganizing worldwide is more difficult to deny. Biological species are, as expected, moving along with the climatic conditions, producing many range shifts and phenological changes that follow basic expectations about the behavior of biodiversity in a warming climate. Predictions and extrapolations for species’ geography based on climate change expected under global, climate model scenarios suggest strongly that the observed shifts are but the first step in a dramatic, broad-scale reorganization of global distributions of biodiversity. As a consequence, many shifts, disappearances, and invasions are expected as biodiversity responds to changing Earth climates. ACKNOWLEDGMENTS I thank valued colleagues David Vieglais, Enrique Martinez-Meyer, Ricardo Scachetti Pereira, and Adolfo Navarro-Sigiienza for many helpful discussions and ideas. This research was supported by grants from the U.S. National Science Foundation.

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68 69. Woodward, F. I., M. R. Lomas, and R. A. Betts. 1998. Vegetation-climate feedback in a greenhouse world. Philosophical Transactions of the Royal Society of London B 353:29-39. 70. Zacherl, D., S. D. Gaines, and S. I. Lonhart. 2003. The limits to biogeographical distributions: insights from the northward range extension of the marine snail, Kelletia kelletii (Forbes, 1852). Journal of Biogeography 30:913-924.

NEW FINGERPRINTS OF HUMAN EFFECTS ON CLIMATE B.D. SANTER Program for Climate Model Diagnosis and Intercomparison, Lawrence Livermore National Laboratory, Livermore, USA T.M.L. WIGLEY National Center for Atmospheric Research, Boulder, USA mTRODUCTION

In 1988, the Intergovernmental Panel on Climate Change (IPCC) was jointly established by the World Meteorological Organization and the United Nations Environment Programme. The goals of this panel were threefold: to assess available scientific information on climate change, to evaluate the environmental and societal impacts of climate change, and to formulate response strategies. The IPCC’s first major scientific assessment, published in 1990, concluded that “unequivocal detection of the enhanced greenhouse effect from observations is not likely for a decade or more” (Houghton et al., 1990, page xxix). Six years later, the IPCC’s second scientific assessment reached a more definitive conclusion regarding human impacts on climate, and stated that “the balance of evidence suggests a discernible human influence on global climate” (Houghton et al., 1996, page 4). This cautious sentence marked a paradigm shift in scientific understanding of the nature and causes of recent climate change. The shift arose for a variety of reasons. Chief amongst these was the realization that the cooling effects of anthropogenic sulfate aerosols had partially obscured the warming signal arising from increasing atmospheric concentrations of greenhouse gases (GHGs). A further major area of progress was the increasing use of so-called “fingerprint” studies, which involve detailed statistical comparisons of modeled and observed climate change patterns. “Fingerprinting” relies on the fact that each climate forcing mechanism (e.g., changes in solar irradiance, volcanic dust, sulfate aerosols, or GHG concentrations) has a unique pattern of response in climate records. Fingerprint studies have greatly enhanced our ability to diagnose cause and effect relationships in the climate system. The third and most recent IPCC assessment went one step further than its predecessor, and made an explicit statement about the magnitude of the human effect on climate. It concluded that “There is new and stronger evidence that most of the warming observed over the last 50 years is attributable to human activities” (Houghton et al., 2001, page 4). This conclusion was based on improved estimates of natural climate variability, better reconstructions of temperature fluctuations over the last millenium, continued warming of the climate system, refinements in fingerprint methodology, and the use of results from more (and improved) climate models, driven by more accurate and complete forcing estimates. The “bottom line” conclusions of the IPCC’s second and third scientific assessments have been endorsed by other independent evaluations, most recently by the US. National Academy of Sciences WAS, 2001). The clear message from these assessments is that human activities have altered both the chemical composition of the

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Earth’s atmosphere and the climate system. Changes in atmospheric composition are an immutable fact, not speculation. Evidence of such anthropogenic perturbations includes increases in well-mixed GHGs, decreases in stratospheric ozone, and changes in the atmospheric burdens of sulfate and soot aerosols. All of these atmospheric constituents interact with incoming solar and outgoing terrestrial radiation and their potential to modify the climate significantly is undeniable. Human-induced changes in their concentrations modify the “natural” radiative balance of Earth’s atmosphere, and therefore perturb climate. Despite the overwhelming scientific evidence of pronounced anthropogenic effects on climate, important uncertainties remain. The experiment that we are performing with the Earth’s atmosphere lacks a suitable control - we do not have a convenient “parallel Earth”, on which there are no human-induced changes in atmospheric chemistry. We must therefore rely on other sources of information to estimate how the Earth’s climate might have evolved in the absence of any human intervention. Such sources include numerical models and proxy data (e.g., tree rings, ice cores, corals, boreholes; Mann and Jones, 2003). Numerical models and paleoclimatic reconstructions will always have uncertainties - so there will always be uncertainties in our estimates of the climate of “undisturbed Earth”, and hence in the magnitude of human effects on climate. One criticism of the “discernible human influence” findings of previous international and national assessments is that they have relied almost exclusively on fingerprint studies involving changes in near-surface temperature. This was a natural focus of initial work, since we live at the Earth’s surface, and are directly affected by surface temperature changes. Instrumental records of near-surface temperature span nearly 150 years and have reasonable spatial coverage for much of this period, making it one of the best-observed climate variables. Furthermore, climate model results indicate that surface temperatures should warm markedly in response to increasing GHG levels, suggesting that it is a good variable to monitor for evidence of an anthropogenic signal. It is not surprising, therefore, that the first fingerprint studies relied heavily on surface temperature (early exceptions are Santer et al., 1996, and Tett et al., 1996, both of which looked at zonal-mean, vertical temperature profiles). More recent fingerprint work, however, has considered a variety of other climate variables, such as changes in ocean heat content (Barnett et al., 2001), Northern Hemisphere sea ice extent (Vinnikov et al., 1999), sea level pressure (Gillett et al., 2003), and tropospheric and stratospheric temperatures (Santer et al., 2003a). These studies illustrate that a human-induced climate change signal is identifiable in many different aspects of the climate system. Such internal consistency, manifest in both observed and simulated climate changes, effectively refutes criticism that IPCC “discernible human influence” conclusions rest on a single variable only. The height of the tropopause is another variable that may provide useful information about the causes of recent climate change (Santer et al., 2003b,c). The tropopause is a transition zone between the turbulently-mixed troposphere (where most weather takes place) and the more stably-stratified stratosphere. It can be defined in a variety of different ways, based on thermal, chemical, or dynamical properties of the atmosphere (Hoinka, 1998; Seidel et al., 2001). In the following, we investigate whether changes in the height of the tropopause provide a further “fingerprint” of human effects on climate.

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DATA AND ANALYSIS METHODS We use a standard thermal definition of the tropopause to track changes in its height (World Meteorological Organization, 1957). This definition relies on lapse rates, which provide information about how temperature changes with increasing height (Figure 1). The algorithm that we employ to estimate tropopause height requires, as input, atmospheric temperature profiles (i.e., temperatures measured at discrete pressure levels above the Earth’s surface), and computes lapse rates from these profiles (Reichler et al., 1996). The algorithm identifies the level at which the lapse rate falls below a critical value of 2”C/km, and then remains less than this value for a specified vertical distance. The exact pressure at which the lapse rate attains this critical value is determined by linear interpolation. We refer to this pressure as PLRT (“pressure of lapse-Kate fropopause”). We calculate pLRT from both climate model and ‘observational’ temperature data. The model data are from the Department of Energy Parallel Climate Model (PCM), jointly developed by the National Center for Atmospheric Research and Los Alamos National Laboratory (Washington et al., 2000). PCM is a state-of-the-art, coupled atmosphere-ocean General Circulation Model (GCM), which has been used to perform a variety of different climate change experiments (Ammann et al., 2003). We analyze seven different experiments here? which differ in terms of the climate forcings included. The three anthropogenic forcings considered are changes in well-mixed greenhouse gases (G), the direct scattering effects of sulfate aerosols (A), and tropospheric and stratospheric ozone (0).The natural forcings are changes in total solar irradiance (S) and volcanic aerosols (V). In the first five experiments, only a single forcing was varied at a time - e.g., G was varied according to historical changes in GHGs, while A, 0, S, and V were held fixed at pre-industrial levels. In the sixth experiment (ALL), G, A, 0, S, and V were varied simultaneously. Only the natural forcings were changed in the final integration (SV). G, A, 0, and S commence in 1872, while V, SV, and ALL start in 1890. All seven experiments end in December 1999. To obtain more reliable estimates of the climate response to the imposed forcing change (i.e., to enhance the externally-forced signal relative to the ‘noise’ of internally-generated variability), four realizations of each experiment were performed. Each realization started from slightly different initial conditions. Since each has a different realization of the noise, averaging over all four approximately doubles the signal-to-noise ratio. For a full description of the experiments and forcings, see Santer et al. (2003~).A long (300 year) control integration was also performed, in which all five forcings were held fixed at pre-industrial values. This control run provides information about the unforced variability of the climate system (i.e., the internally-generated noise), which is a critical component of “fingerprint” detection work. Observational estimates of tropopause height were obtained from ‘reanalyses’, which are optimal combinations of numerical weather forecasts and observations (Pawson and Fiorino, 1999; Santer et al., 1999). Two different reanalysis products were used. The first (NCEP) was from the National Center for Environmental Prediction and the National Center for Atmospheric Research (Kalnay et al., 1996). The second (ERA) was performed by the European Centre for Medium-Range Weather Forecasts (Gibson et al., 1997). NCEP data were available from 1948 to 2001, but data before 1979 are

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affected by serious inhomogeneities (Pawson and Fiorino, 1999; Santer et al., 1999) and were not used in our fingerprint analysis. ERA data were available for a much shorter period of time (1979 to 1993). As in the case of PCM data, PLRT was calculated from the NCEP and ERA atmospheric temperature profiles. Different climate forcing mechanisms have different effects on atmospheric temperature profiles, and hence on PLRT. Previous work has shown that PLRT is strongly influenced by temperature changes of the atmospheric layers above and below the tropopause (Santer et al., 2003b,c). To diagnose how different forcings affect PLRT,it is useful to calculate the average temperatures of the lower stratosphere and mid- to upper troposphere. In the real world, temperatures in these atmospheric layers are monitored by channels 4 and 2 of the satellite-based Microwave Sounding Unit (MSU). We calculated ‘equivalent’ MSU temperatures from PCM, NCEP, and ERA, using weighting functions to mimic how the MSU instrument samples the real-world atmosphere (Santer et al., 1999). ‘Equivalent’ MSU temperatures are referred to below as T4 (lower stratosphere) and T2 (mid to upper troposphere). GLOBAL-MEAN CHANGES

In both the PCM ALL and SV experiments, there is a small overall increase in tropopause height from 1890 to roughly 1965. This increase corresponds to an overall decrease in the pressure of the tropopause: i.e., PLRT declines by -1-2 hPa (Figure 2). From 1965 to 1999, tropopause height increases markedly in ALL, which includes anthropogenic forcings, but not in SV, which has solar and volcanic forcing only. The simulated height increase in ALL is in agreement with the global-mean height changes in both reanalyses (Figure 2)’. The multiple realizations of ALL and SV provide information about uncertainties in the climate response to the imposed forcings. These uncertainties arise from the inherently unpredictable noise of internally-generated variability. The four realizations of ALL and of SV define two different ‘envelopes’ of possible climate trajectories. These two envelopes clearly diverge in the 1980s. In ‘PCM world’, it is clear that the increase in tropopause height over the last two decades of the 20th century could not be due to the combined effects of natural internal variability and forcing by the Sun and volcanoes alone. Superimposed on these multi-decadal changes in tropopause height are large, shortterm (2-3 year) height decreases associated with the eruptions of Santa Maria (in 1902), Agung (in 1963), El Chich6n (in 1982) and Pinatubo (in 1991). These volcanic signals are large relative to the internal ‘noise’ of PLRT in volcanically-quiescent periods. The volcanic tropopause height signals in PCM are larger than in NCEP and ERA, for reasons discussed in Santer et al. (2003~). Figure 3 provides a simple conceptual model for interpretation of these low- and high-frequency PLRT changes. Calculations performed with simple radiative convective models and more complex atmospheric GCMs show that increases in atmospheric C02 cool the stratosphere and warm the troposphere (e.g., Hansen et al., 1984; Manabe and Wetherald, 1987). Both of these changes tend to increase tropopause height. Depletion of stratospheric ozone also causes a net increase in tropopause height through strong cooling of the stratosphere.” In contrast, volcanic aerosols injected into the stratosphere absorb

73 incoming solar radiation and outgoing longwave radiation, thus warming the stratosphere and cooling the troposphere. Both of these changes decrease tropopause height. The previously-described PLRT changes in PCM, NCEP, and ERA are qualitatively consistent with this simple conceptual model. CONTRIBUTIONS OF INDIVIDUAL FORCINGS TO TROPOPAUSE HEIGHT CHANGES The PCM "individual forcing" experiments help to isolate the effects of different forcings on the atmospheric temperature profile, and hence on tropopause height. From the ensemble-means of G, A, 0, S, V, and ALL, we first calculated zonal-mean, monthlymean anomalies,"' and then computed the total linear changes" in T4, T2, and PLRT over 1900-1999. Consider first the results for stratospheric temperature changes (Figure 4A). ALL is characterized by coherent cooling of the stratosphere over the 20th century. This cooling is smallest in the tropics and largest at high latitudes in the Southern Hemisphere. Stratospheric ozone depletion is the major contributor to the T4 changes in ALL, consistent with findings by Ramaswamy et al. (1996). Ozone forcing also influences the hemispheric asymmetry in ALL's T4 changes,v since ozone-induced cooling is largest at high latitudes in the Southern Hemisphere, where stratospheric ozone decreases are greatest. The stratospheric temperature response to well-mixed GHGs has a similar (but smaller) hemispheric asymmetry. The total linear changes in T4 caused by A, S, and V are much smaller than those arising from 0 and G. The direct (scattering) effect of anthropogenic sulfate aerosols yields a small net cooling of the stratosphere over 1900-1999, while the assumed increase in solar irradiance in the S experimentVileads to a slight warming of the stratosphere.vii Volcanic aerosols also cause a small overall warming of the stratosphere, primarily due to the occurrence of two large eruptions near the end of the century. The troposphere warms at most latitudes in the ALL case, with maximum warming in the tropics (Figure 4B).v"1 Well-mixed GHGs are the major contributor to this warming. The positive contribution of G is partly offset by the small net tropospheric coolings caused by sulfate aerosols, ozone, and volcanoes. Note that the T2 changes induced by sulfate aerosols have pronounced hemispheric asymmetry, with maximum tropospheric cooling in the Northern Hemisphere (where anthropogenic sulfate aerosol forcing is largest). Although the net effect of ozone changes is to cool T2, low-latitude increases in tropospheric ozone warm the tropical troposphere. Changes in solar irradiance also yield a small warming of T2. Figure 4C illustrates that ozone and well-mixed GHGs are the dominant influences on the tropopause height changes in ALL. Both forcings increase the height of the tropopause at all latitudes. The hemispheric asymmetry in ALL's height changes (with largest height increases at high latitudes in the Southern Hemisphere) is primarily due to hemispheric asymmetries in the T4 responses to 0 and G (Figure 4A). As expected on the basis of our conceptual model (Figure 3), A and V produce slight decreases in tropopause height (increases in PLRT).Since forcing by S warms both T4 and T2, with offsetting effects on PLRT,the net effect of S depends on the relative magnitudes of stratospheric and tropospheric warming. In PCM, tropospheric warming predominates, and the net effect of S is a small increase in tropopause height.

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Figure 5 summarizes the effects of different forcings on the global-mean changes in tropopause height, T4, and T2. It shows the total linear changes in these three variables for the ALL experiment and the five individual forcing cases (G, A, 0, S, and V). Over 1900 to 1999, anthropogenic forcing by ozone and well-mixed GHGs explains over 80% of the overall height increase in ALL (Figure 5A; see also Santer et al., 2003~).The ozone effect on pLRT is manifest primarily through cooling of the stratosphere (Figure 5B). The influence of well-mixed GHGs occurs mostly through warming of the troposphere (Figure 5C). In PCM, natural external forcings make only a small contribution to the simulated 20thcentury changes in tropopause height and atmospheric temperatures. FINGERPRINT ANALYSIS We have shown that there is consistency between the global-mean tropopause height changes in reanalyses and the PCM experiment with combined natural and anthropogenic forcing (Figure 2). Results from the SV experiment indicate that this global-mean correspondence could not be achieved by natural forcing only. Global-mean agreement alone, however, does not provide compelling evidence of causality. A more reliable way of studying cause-effect relationships involves comparison of modeled and observed spatial patterns. As noted previously, the expected pattern of tropopause height change in response to combined natural and anthropogenic forcing (the “fingerprint”) has pronounced meridional structure and hemispheric asymmetry (Figure 4C). These largescale features are physically interpretable: they are related to the characteristic patterns of zonal-mean atmospheric temperature change arising from forcing by 0 and G (Figure 4A,B). Identification of the PCM ALL fingerprint pattern in reanalyses would enable us to attribute observed tropopause height changes to the combined effects of anthropogenic and natural forcing. We use a standard “fingerprinting” technique (Hasselmann, 1979). The fingerprint is obtained from the PCM ALL ensemble mean, and therefore represents the expected climate-change response to combined forcing by G, A, 0, S, and V. Our strategy is to search for an increasing expression of f in the reanalysis tropopause height data, and to estimate the “detection time” - the time at which the fingerprint becomes consistently identifiable gj a stipulated 5% significance level. We use both “raw” and “optimized” versions of f , referred to in Figure 6 as “RAW’ and :OPT”. Optimization is a standard statistical procedure that enhances the detectability of f by rotating the fingerprint away from high noise components.” We also perform the fingerprint analysis with and without the global-mean component of tropopause height change. Removal of global-mean changes focuses attention on smaller spatial scales, and constitutes a more rigorous test of modelldata pattern similarity. Fingerprinting relies on estimates of the internally-generated climate noise, which are obtained here from 300-year control runs (with no changes in external forcings) performed with PCM and the ECHAMWOPYC model (ECHAM) of the Max-Planck Institute for Meteorology in Hamburg (Roeckner et al., 1996). The use of control runs from two different models accounts for uncertainties in model-based estimates of internal variability. We note that our fingerprint test is performed with full 1atitudeAongitude patterns of tropopause height change rather than the zonal-mean patterns shown in Figure

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75 4C. The full 1atitudeAongitude patterns are shown in Santer et al. (2003c), which also provides further technical details of the fingerprinting procedure. In our fingerprint method, the assumed “start date” for monitoring tropopause height changes is 1979 (the beginning of both the ERA data and of the more reliable portion of the NCEP reanalysis). We need a miEimum- of 10 years of reanalysis data in which to search for the model-based fingerprint f . If f cannot be detected in the first 10 year “chunk” of NCEP or ERA (i.e., in data from 1979-1988), we add an additional year of data (1989), and repeat the detectionprocedure. This extension of the analysis period continues until we have either detected f , or the reanalysis data end (in 2001 for NCEP, and 1993 for ERA). When the global-mean is included, the ALL tropopause height fingerprint can be identified in both NCEP and ERA (Figure 6). Detection of the “,W’ fingerprint occurs in 1988 - the earliest possible detection date. Optimization of f cannot improve this result (which is already the best possible), When the global-mean is removed, and attention focuses on smaller spatial scales, f can be identified in the NCEP data only, and at a later date (1995) than in the “mean included” case. This suggests that the ERA data (which ends in 1993) is simply too short to identify the “mean removed” fingerprint. Our detection results are relatively insensitive to the choice of model control run used to estimate natural variability noise or optimize the fingerprint. CONCLUSIONS

In evaluating how well a novel has been crafted, it is important to look at the internal consistency of the plot. Critical readers examine whether the individual storylines are neatly woven together, and whether the internal logic makes sense. We can ask similar questions about the “story” contained in observational records of climate change. The evidence from previous fingerprint studies indicates that the climate system provides us with an internally consistent account of the causes of recent climate change. Over the last century, the Earth’s oceans and land surface have warmed (Bamett et al., 2001; Jones et al., 1999). Glaciers have retreated over most of the globe. Sea level has risen. Snow and sea-ice extent have decreased in the Northern Hemisphere (Vinnikov et al., 1999). The stratosphere has cooled, and there are now reliable indications that the troposphere has warned (Mears et al., 2003; Santer et al., 2003a). All of these changes are consistent with our scientific understanding of how the climate system should be responding to anthropogenic forcing. They are not consistent with the changes that we would expect to occur due to natural forcings only. Changes in tropopause height are yet another piece of the climate-change puzzle. Other studies have documented an increase in the height of the tropopause in radiosondes and reanalyses (Highwood et al., 2000; Randel et al., 2000; Seidel et al., 2001). Our work is the first to illustrate that observed changes are consistent with climate model results (Santer et al., 2003b,c). This consistency holds for both global-mean increases, as well as for more complex spatial patterns of tropopause height change. We find that the simulated increase in tropopause height is mainly due to two anthropogenic factors: the effects of stratospheric ozone depletion (which cools the stratosphere) and increases in well-mixed greenhouse gases (which warm the troposphere). effects are necessary to explain the observed height increases.

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Our results strengthen the scientific case for a discernible human impact on global climate. We note, however, that there are still significant uncertainties in climate models, in observations, in estimates of climate forcings, and in our physical understanding of the climate system. The difficult problem that confronts us - as citizens of this planet - is how to act in the face of both scientific uncertainty and growing scientific evidence that our actions are altering global climate. We should be very clear about one point. The decisions we reach today will influence the climate that future generations inherit. REFERENCES 1. 2. 3. 4.

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29. Seidel, D.J., R.J. Ross, J.K. Angell, and G.C. Reid, 2001: Climatological characteristics of the tropical tropopause as revealed by radiosondes. J. Geophys. Res., 106,7857-7878. 30. Shaviv, N.J., and J. Veizer, 2003: Celestial driver of Phanerozoic climate? GSA Today, 13,4-10. 31. Tett, S.F.B., J.F.B. Mitchell, D.E. Parker and M.R. Allen, 1996: Human influence on the atmospheric vertical temperature structure: Detection and observations. Science, 274, 1170-1173. 32. Vinnikov, K.Y., A. Robock, R.J. Stouffer, J.E. Walsh, C.L. Parkinson, D.J. Cavalieri, J.F.B. Mitchell, D. Garrett, and V.F. Zakharov, 1999: Global warming and Northern Hemisphere sea ice extent. Science, 286, 1934-1937. 33. Washington, W.M., J.W. Weatherly, G.A. Meehl, A.J. Semtner Jr., T.W. Bettge, A.P. Craig, W.G. Strand, J. Arblaster, V.B. Wayland, R. James and Y . Zhang, 2000: Parallel Climate Model (PCM) control and transient simulations. Clim. Dyn., 16, 755-774. 34. Wigley, T.M.L., B.D. Santer, J.M. Arblaster, C. Ammann, G.A. Meehl, and M.F. Wehner, 2003: Testing for additivity in climate model responses to external forcing: The effect of model drift.In preparation. 35. World Meteorological Organization (WMO), 1957: Meteorology: A threedimensional science. Second Session of the commission for aerology. WMO Bull., 6(4), 134-138.

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Temperature (Kelvin)

Figure 1.: Typical low-latitude atmospheric temperature profile in the NCEP reanalysis. Results are climatological means over 1979-1997, and have been averaged from the equator to 30"N. The estimated tropopause pressure, PLRT,was computed with the algorithm of Reichler et al. (1996), and is indicated by the dashed horizontal line.

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Global Mean Changes in Tropopause Pressure A

-5 m m0)

6E

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Figure 2.: Time series of global-mean monthly-mean anomalies in tropopause pressure, PLRT. Model results are from the PCM experiments with combined natural and anthropogenic forcing (ALL), and with natural forcing only (SV). There are four realizations of each experiment. The shaded areas mark the range between the highest and lowest values of the realizations. Darker shading denotes ALL results; lighter shading represents SV. The ensemble-mean values of ALL and SV are given by thin solid and thin dashed lines (respectively). All model PLRT anomalies were defined relative to climatological monthly means computed over 1890-1909. Estimates of 'observed' PLRT are from the NCEP reanalysis (thick solid line). Pre-1960 NCEP data were ignored because of deficiencies in the coverage and quality of assimilated radiosonde data. NCEP was forced to have the same mean as ALL over 1960-1999. Both PCM and NCEP results were low-pass filtered. Note that an increase in tropopause height corresponds to a decrease in PLRT.

PI

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- Baseline temperature profile Cooling - - - - - -- Warming

Figure 3.: Conceptual model for the effect of three different forcings on tropopause height. The solid black lines are the ‘baseline’ atmospheric temperature profiles. The forcings shown here - depletion of stratospheric ozone, increasing atmospheric COz, and explosive volcanic eruptions - perturb this base state. The effect of the first two forcings is to increase tropopause height (indicated by the upward-pointing arrows), while volcanic aerosols decrease the height of the tropopause. The actual temperature perturbations associated with these forcings are more complex as a function of both altitude and latitude than the idealized changes illustrated here (Santer et al., 2003b).

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Zonal Mean Changes in T4, T2, and pLRTin PCM 0.5 0 -0.5 0 ,0

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Figure 4.: Zonal-mean changes in stratospheric temperature (T4; panel A), tropospheric temperature (T2; panel B) and tropopause height ( p ~ p , ;~panel C). Results are expressed as the total linear changes over 1900-1999, and were computed using ensemble-mean data from the PCM G, A, 0, S, V, and ALL experiments.

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Tropopause Height and Temperature Changes in PCM Contributions over 1900-1999

0.8 0.6 0.4 5 0.2

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V (volcanoes) I All forcings E 3 SUM (G+A+O+S+V)

Figure 5.: Total linear changes in global-mean, monthly-mean tropopause height (A), stratospheric temperature (B), and tropospheric temperature (C) in PCM experiments with individual forcings (G, A, 0, S, and V) and combined natural and anthropogenic forcings (ALL). Linear changes were calculated for the period 1900-1999 using ensemble-mean data. Anomalies were defined relative to climatological monthly means computed over 1900-1999. “SUM” is the sum of the linear changes in the five experiments with individual forcing.

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Mean included I

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Figure 6.: Detection times for the tropopause height “fingerprint” simulated in the PCM ALL experiment. Here is the (1atitudeAongitude) pattern of tropopause height change in response to combined natural and anthropogenic forcing, and is defined as described in Santer et al. (2003~).The fingerprint is searched for in two different ‘observational’ datasets (the NCEP and ERA reanalyses). Both raw and optimized versions of the fingerprint are employed (RAW and OPT). The left (right) side of the figure shows detection results achieved when the global-mean component of tropopause height change is included (removed). Control runs from two different models (PGM and ECHAM) are used for estimating natural variability statistics and optimizing f .The presence of a bar indicates positive detection of the fingerprig. The longer the bar, the earlier the detection date. The absence of a bar means that f could not be identified before the end of the reanalysis (2001 for NCEP, 1993 for ERA).

8 ‘ It is also in agreement with the changes in ERA (not shown). Depletion of stratospheric ozone cools both the stratosphere and the troposphere. These changes have effects of opposite sign on tropopause height. The stratospheric cooling influence predominates, so the net effect of ozone depletion is to raise tropopause height (Figure 3). Relative to climatological monthly means over 1900-1999. I” The total linear change is expressed as b x n, where b is the slope parameter of the leastsquares linear trend (in hPa/month or “C/month),calculated over n months. v Note that there is residual climate drift in the PCM control run. This drift is related to the behavior of sea ice. It is not hemispherically symmetric, and has a pronounced signature in near-surface temperature fields (Wigley et al., 2003). Since this residual climate drift was not subtracted from the PCM perturbation experiments analyzed here, it influences the results shown in Figure 4, and imparts some hemispheric asymmetry to the estimated linear changes. This “drift contamination” effect is largest close to the Earths surface, and is probably small for T4 changes. vl Total solar irradiance changes were prescribed according to Hoyt and Schatten (1993). There was no wavelength dependence of the forcing. vii Recently, Shauiu and Veizer (2003) have argued that solar-induced changes in cosmic ray flux influence the behavior of low-level tropical clouds, and that this mechanism might explain nearly two-thirds of observed near-surface temperature changes over the past 150 years. This argument cannot explain the pronounced cooling of the extratropical stratosphere seen in radiosondes and satellite-based MSU measurements (see, e.g., Santer et al., 1999, 2003a). Cosmic ray-induced amplification of the direct effect of solar irradiance changes (direct irrahance changes are the only solar forcing employed here) would also lead to marked discrepancies between modeled and observed T2 changes. viu Note that T2 cools a t high latitudes in the Southern Hemisphere. T h s occurs some of the strong stratospheric cooling in this region is sampled by the T2 weighting function used to compute an ‘equivalent’ MSU temperature. ix Here, this rotation is performed in the space of the first 15 Empirical Orthogonal Functions (EOFs) of the PCM and ECHAM control runs.

PALEOCLIMATE IMPLICATIONS FOR RECENT HUMAN INFLUENCE ON CLIMATE MICHAEL E. MANN Department of Environmental Sciences, University of Virginia Charlottesville, USA Documenting past temperature changes is of particular importance in placing recent climate change in an appropriate long-term context. Because the fundamental boundary conditions on the climate (the parameters of the earth's orbit relative to the sun, and global patterns of vegetation and continental ice cover) have not changed appreciably over the past one-to-two millennia, the variations that have occurred in climate during this period are likely representative of the range of natural climate variability that might be expected in the absence of any human influence on climate. Placing modem (20th21st century) global warming in this longer-term context can thus aid in our ability to determine the role of anthropogenic factors, such as human greenhouse gas concentration increases, in more recent climate changes. Instrumental meteorological records can only provide a widespread direct indication of climate changes over roughly the past century. Prior to that, relatively few instrumental records are available (Jones et al, 1999). However, a number of distinct approaches exist for describing climate variations over a timeframe of roughly the past millennium. Among these is the use of theoretical models of the climate system that are driven with estimated changes in external parameters or 'forcings' such as greenhouse gas concentrations and solar output, which tend to warm the climate, and the fiequency and intensity of explosive volcanic eruptions which cool the climate through injecting reflective sulphate aerosol into the atmosphere (Crowley, 2000; Gerber et al, 2002; Bauer et al, 2003) This approach to reconstructing the past temperature history is limited by the imperfectly known history of these changes in forcing, which are typically estimated indirectly from trapped gas, radioisotopes and volcanic dust signals left behind in ice cores (Crowley, 2000). Moreover, the reconstruction is limited by any uncertainties in the model's representation of actual climate processes and responses. Finally, the approach only indicates the forced component of climate change; it cannot estimate the possible role of internal dynamics (e.g. natural changes in ocean circulation) in the actual climate changes in past centuries. Human documentary evidence provides another source for reconstructing climate in past centuries (see e.g. Wigley et al, 1981; Bradley, 1999). Records of frost dates, droughts, famines, the freezing of water bodies, duration of snow cover, and phenological evidence (e.g. the dates of flowering of plants, and the ranges of various species of plants) can provide insight into past climate conditions. Human accounts of mountain glacier retreats and advance during past centuries, diary or anecdotal evidence of weather conditions, and even a hand full of several centuries-long thermometer measurements, furthermore, are available in Europe for more than 1000 years. Plentiful human documentary evidence is limited, however, to those regions brimarily Europe and Eastern Asia) where a written tradition existed. They are thus not useful for documenting hemispheric, let alone global-scale climate variations, several centuries into the past. It is also important to note that human documentary records must be interpreted with caution,

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as they are not equivalent in their reliability to actual instrumental measurements of meteorological variables. Typically, these records provide indirect and potentially biased snapshots in time of climate-related phenomena. Geological evidence from terminal glacial moraines indicating the advance of mountain glaciers in past centuries can also provide inferences into past climate changes. However, owing to the complex balance between local changes in melting and ice accumulation, and the effects of topography, all of which influence mountain glacier extents, it is difficult to ascertain the true nature of temperature changes simply from evidence of retreat of mountain glaciers (e.g. Folland et al, 2001). Both increased winter precipitation and cooler summer temperatures can lead to the growth of a glacier, and large or even moderate glaciers respond slowly to any underlying climate changes. Estimates of long-term ground temperature trends from temperatures profiles retrieved from terrestrial borehole data over the globe (Huang et al, 2000) can also provide complementary large-scale information regarding ground surface temperature trends in past centuries, but impacts of changes in seasonal snow cover, land-surface changes, and other factors appear to yield biased estimates of past surface air temperature changes from such data (Mann et al, 2003). A more quantifiable source of information on climate changes in past centuries is provided by 'proxy' indicators of climate change - natural archives of information which, by their biological or physical nature, record climate-related phenomena (Bradley, 1999; Folland et al, 2001). Certain proxy indicators, including most sediments cores, ice cores, and preserved pollen do not have the capability to record climate changes at high temporal resolution, and are thus generally not useful for reconstructing climate changes over the past several centuries. However, high-resolution (annually-resolved) proxy climate records such as growth and density measurements from tree rings, laminated sediment cores, annually resolved ice cores, and isotopic information from corals can be used to describe year-to-year patterns of climate in past centuries (Bradley and Jones, 1993; Mann et al, 1998; 1999; Jones et al, 1998; Crowley and Lowery, 2000; Briffa et al, 2001). These indirect measurements of climate change vary considerably in their reliability as indicators of long-term climate (varying in the degree of influence by nonclimatic effects, the seasonal nature of the climate information recorded, and the extent to which the records have been "verified" by comparison with independent data). However, when taken together, and particularly, when combined with historical documentary information and the few long instrumental climate records available, they can provide a meaningll annually-resolved documentation of large-scale climate changes in past centuries, including patterns of surface temperature change, drought, and atmospheric circulation. Global assemblages of such high-resolution proxy indicators can be related to the modem instrumental surface temperature record, and then used to yield reconstructions of large-scale surface temperature patterns over several centuries, back over roughly the past millennium. The detailed spatial patterns of these reconstructions can often provide insights into the underlying climate changes. Hemispheric or global mean surface temperature estimates can be derived by spatially averaging over such estimates of past large-scale patterns of surface temperature change. It is most meaningful to estimate the average surface temperature changes for the Northern Hemisphere, where considerably more widespread past data is available. Different estimates of Northern Hemisphere

8 8 temperature changes over the past millennium have been made, using different sources of proxy data, some of which are representative of the full Northern Hemisphere, others of which are more indicative of extra-tropical regions of the Northern Hemisphere. The various proxy and model-based hemispheric temperature estimates, taken on the whole, indicate relatively modest variations in temperature over the past 1000 years, prior to the pronounced 20th century warming (Figure 1). At the full hemispheric scale, temperatures appear to have been slightly warmer (a couple of tenths of a degree C) during the period AD 1000-1400 than during the later, colder period AD 1400-1900. There is, however, no other multi-decadal period during the past millennium that is comparable, in warmth, to the latter 20th century. In fact, this conclusion likely extends to at least the past two millennia (Briffa and Osborn, 1999; Yang et al, 2002), though the fewer available proxy data lead to considerably greater uncertainty in reconstructions prior to the past thousand years. Some extra-tropical summer temperature reconstructions (Esper et al, 2002) suggest wider swings in temperature, including greater cooling during the 17th-19th century than is evident in either the instrumental, model, or proxy-based estimates. The greater variability in this case probably arises from the emphasis on extratropical continental regions (Mann, 2002). Regional variations in surface temperature in past centuries appear to have often been of greater amplitude than those for hemisphere mean, but were often not synchronous. In fact, offsetting patterns of cooling and warming in different regions in past centuries (e.g. Bradley and Jones, 1993; Hughes and Diaz, 1994; Crowley and Lowery, 2000) yield far more modest variations evident in hemispheric mean temperature. For this reason, regional evidence can often provide a very misleading picture of large-scale climate changes. While European temperatures indicate a distinct cold phase from the 17th-19th centuries for example (the so-called "Little Ice Age" of Europe--e.g. Lamb, 1965), with average winter temperatures during the coldest decades of the 17th century probably 2' C or colder relative to late 20th century temperatures (e.g. Shindell et al, 2001), the trend in Northern Hemisphere mean temperature (i.e. Figure 1) shows a far smaller, and more steady, long-term pattern of cooling prior to the 20th century. It is probable that the greater cooling during the "Little Ice Age" of Europe was associated with a regional enhancement of cooling by a tendency for the 'negative phase' of an atmospheric circulation pattern, the 'North Atlantic Oscillation' ("AO'), that is associated with a southward displacement in the mean position of the winter jet stream over the North Atlantic ocean and neighboring continental regions. Recent evidence suggests that the NAO can be altered, for example, by changes in the output of the sun (Shindell et al, 2001). Such changes may have led to enhanced cooling in Europe during the 18th century, when solar output was slightly weaker, and winter atmospheric circulation changes favored strong cooling in Europe, but much weaker cooling for the Northern Hemisphere on the whole (Shindell et al, 2001). The complexity of such regional variations in temperature trends underscores the principle that it is perilous to draw conclusions regarding hemispheric or global temperature trends from isolated regional information. While some challenges remain in reducing uncertainties in the regional details of past climate change, the conclusion that late 20th century hemispheric-scale warmth is anomalous in a long-term (at least millennial) context, and that anthropogenic factors

8 likely play an important role in explaining the anomalous recent warmth, represents the consensus view of the climate research community (Folland et al, 2001).

1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000

Time A.D. Figure 1. Comparison of proxy-based NH temperature reconstructions [Jones et al, 1998; Mann et al, 1999; CrowZey andLowery, 20001 with model simulations of NH mean temperature changes over the past millennium based on estimated radiative forcing histories [Crowley, 2000; Gerber et al, 2002--results shown for both a 1.5' C I 2 x C02 and 2.5" C I 2 x C02 sensitivity; Bauer et al, 20031. Also shown is an independent reconstruction of warm-season extra-tropical continental NH temperatures [Esper et al, 20021. All reconstructions have been scaled to the annual, full Northern Hemisphere mean, over an overlapping period (1856-1980), using the NH instrumental record [Jones et al, 19991 for comparison, and have been smoothed on time scales of >40 years to highlight the long-term variations. The smoothed instrumental record (1856-2000) is also shown. The gray shading indicates estimated two-standard error uncertainties in the Mann et a1 [1999] reconstruction [Adapted from Mann, 20021.

9 0 REFERENCES 1. Bauer, E., Claussen, M., Brovkin, V., Assessing climate forcings of the earth system for the past millennium, Geophys. Res. Lett., 30 (6), 1276-1279, doi: 10,1029/2002GL016639,2003. 2. Bradley, R.S., Paleoclimatology: reconstructing climates of the Quaternary. Harcourt , Academic Press, San Diego, 61Opp, 1999. 3. Bradley, R.S., and P.D. Jones, "Little Ice Age" summer temperature variations: their nature and relevance to recent global warming trends, The Holocene, 3, 367376,1993. 4.Bradley, R.S., Briffa, K.R., Crowley, T.J., Hughes, M.K., Jones, P.D, Mann, M.E., Scope of Medieval Warming, Science, 292,201 1-2012,2001. S.Briffa, K.R., T.J. Osbom, F.H. Schweingruber, I.C. Harris, P.D. Jones, S.G. Shiyatov, S.G. and E.A. Vaganov, Low-frequency temperature variations from a northern tree-ring density network. J. Geophys. Res., 106,2929-2941,2001. 6. Briffa, K.R., and T.J. Osbom, Seeing the Wood from the Trees, Science, 284, 926-927, 1999. 7. Crowley, T.J., Causes of Climate Change Over the Past 1000 Years, Science, 289, 270-277, 2000. 8. Crowley, T.J., and T. Lowery, How Warm Was the Medieval Warm Period?, Ambio, 29, 51-54,2000. 9.Esper, J., E.R. Cook and F.H. Schweingruber, Low-frequency signals in long treeline chronologies for reconstructing past temperature variability, Science, 295, 2250-2253,2002. 10. Folland, C.K., T.R. Karl, J.R. Christy, R.A. Clarke, G.V. Gruza, J. Jouzel, M.E. Mann, J. Oerlemans, M.J. Salinger, S.-W. Wang, Observed Climate Variability and Change, in Climate Change 2001: The ScientiJic Basis, edited by J.T. Houghton et al., pp. 99-181, Cambridge Univ. Press, New York, 2001. 11. Gerber, S., F. Joos, P. Briigger, T. F. Stocker, M. E. Mann, S. Sitch, and M. Scholze, Constraining temperature variations over the last millennium by comparing simulated and observed atmospheric COz, Climate Dynamics, 20,28 1299,2003. 12. Huang, S., H. N.Pollack and P.-Y. Shen, Temperature Trends Over the Past Five Centuries Reconstructed from Borehole Temperature, Nature 403,756-758,2000. 13. Hughes, M.K. and H.F. Diaz, "Was there a 'Medieval Warm Period' and if so, when and where?" Climatic Change, 26, 109-142. 1994. 14. Jones, P.D., M. New, D.E. Parker, S. Martin, and I.G. Rigor, 1999: Surface air temperature and its changes over the past 150 years. Reviews of Geophysics 37, 173-199. 15. Lamb, H.H., The early medieval warm epoch and its sequel, Paleoceanogaphy, Paleoclimatology, Paleoecology, 1, 13-37, 1965.

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16. Mann, M.E., The Value of Multiple Proxies, Science, 297, 1481-1482,2002. 17. Mann, M.E., R.S. Bradley, and M.K. Hughes, Global-scale temperature patterns and climate forcing over the past six centuries, Nature, 392, 779-787, 1998. 18. Mann, M.E., R.S. Bradley, and M.K. Hughes, Northern Hemisphere Temperatures During the Past Millennium: Inferences, Uncertainties, and Limitations, Geophysical Research Letters, 26, 759-762, 1999. 19. Mann, M.E., Rutherford, S., Bradley, R.S., Hughes, M.K., Keimig, F.T., Optimal Surface Temperature Reconstructions Using Terrestrial Borehole Data, Journal of Geophysical Research, 108 (D7), 4203, doi: 10.1029/2002JD002532,2003. 20. Shindell, D.T., Schmidt, G.A., Mann, M.E., Rind, D., Waple, A., Solar forcing of regional climate change during the Maunder Minimum, Science, 294, 2149-2152, 2001. 21. Wigley, T.M.L., Ingram, M.J., Farmer, G., Past Climates and their impact on Man: a review. in Climate and Histoly, Cambridge University Press, eds T.M.L. Wigley, M.J. Ingram, G. Farmer, pp. 3-50, 1981. 22. Yang, B., Braeuning, A., Johnson, K.R. and Yafeng, S., General characteristics of temperature variation in China during the last two millennia, Geophys. Res. Letts., 10.1029/2001GL014485,2002.

EVIDENCE FOR GLOBAL WARMING

DAVID PARKER AND CHRIS FOLLAND Hadley Centre, Met Office, U.K. ABSTRACT We review the evidence for global warming, firstly focusing on ocean surface water and air temperatures, and on air temperatures measured at land stations. We assess the various uncertainties involved in the use of these data to monitor climate, namely time-varying biases, random and sampling errors, and the uncertainties arising from the absence of data in substantial regions of the world especially in the earlier parts of the instrumental record. We then consider the radiosonde and satellite temperature records for the atmosphere up to the lower stratosphere. In the troposphere the pattern of warming is somewhat different from that at the surface, while in the lower stratosphere cooling is seen, as would be expected with an increase in greenhouse gases and a decrease in ozone. We offer an explanation as to why almost worldwide surface warming in the last 25 years has not been accompanied by warming in the tropical troposphere. SOURCES OF UNCERTAINTY IN TEMPERATURE ANALYSES The major sources of uncertainty in estimating regional and global temperature deviations’ and trends are: incomplete geographical and temporal coverage of data; random measurement and sampling errors; and uncertainties due to systematic biases andor in the bias-corrections. Application of optimum averaging techniques, and additional estimates of bias-uncertainties in global blended land surface air temperatures and sea surface temperatures, show that the influences of data gaps, and of random measurement and sampling errors, are much smaller than the effects of uncertainties in our knowledge of the biases (Figure 1 and Folland et al., 2001b). Despite the latter uncertainties, the total two standard error uncertainty is only about one third of the warming signal, as expressed in the conclusion of the Intergovernmental Panel on Climate Change that global warming in the twentieth century was 0.6 *0.2“C. Broadly similar results are seen for the two hemispheres.

’ These are usually expressed as differences from a reference or “normal” period such as 1961- 1990, and termed “anomalies”. 92

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0.5

1 1900

1950

2000

FIGURE 1.: Global surface temperature anomalies PC), 1861-2000, smoothed ) estimated porn with a 21-term binomial filter. Uncertainties (shading: 5 2 ~ were annual values allowing for serial correlation. Dark shading: uncertainties from reduced space optimal averaging alone; intermediate shading: with added sea surface temperature bias-correction and urbanisation uncertainties; light shading: also including land thermometer exposure uncertainties. From Folland et al., 2001b. It is worth pointing out that the situation would be somewhat different on substantially smaller space scales. Here uncertainties, due to data gaps in particular, would increase quite strongly in the late nineteenth and early twentieth centuries, except for a few well-observed regions like Europe.

REASONS FOR CONFIDENCE IN TEMPERATUREANALYSES The agreement between global trends of land surface air temperature, marine air temperature and sea surface temperature over the last 150 years (Figure 2, updated and slightly amended from P C C 2001 (Folland et al, 2001a)) constitutes strong evidence for the reality of the trends, because these data sets are obtained by almost independent methods, and wholly independent after 1893. The agreement between the land surface air temperature and the sea surface temperature is supported (Folland et al., 2001b) by the close agreement between the observed trends of land surface air temperature and those simulated by an atmospheric model forced with the observed sea surface temperatures