All signatories to the Open Letter express their support in their personal capacity and not on behalf of their institution. If you also want to support this initiative as an academic, as a representative of a civil society organization, or as an individual citizen, please  — SIGN HERE

See below who initiated and first signed our call for an International Non-Use Agreement on Solar Geoengineering


Meet the 16 scholars who are the Initiators of the Open Letter calling for an International Non-Use Agreement on Solar Geoengineering

Prof. Saleem H. Ali

Chair and Distinguished Professor of Geography and Spatial Sciences, University of Delaware; Member of the Scientific and Technical Advisory Panel of the Global Environment Facility, Member of the United Nations International Resource Panel

Assoc. Prof. Prakash Kashwan

Associate Professor of Environmental Studies, Brandeis University, USA; Expert Group for Scoping of Transformative Change Assessment, Intergovernmental Platform on Biodiversity & Ecosystem Services (IPBES)

Prof. Louis Kotzé

Research Professor, North-West University South Africa; Senior Professorial Fellow in Earth System Law, Lancaster; Klaus Töpfer Sustainability Fellow, Institute for Advanced Sustainability Studies, Potsdam

Prof. Chukwumerije Okereke

Professor of Climate Governance and International Development and Director of the Centre for Climate Change and Development at the Alex-Ekwueme Federal University Ndufu-Alike

Dr. Åsa Persson

Research Director, Stockholm Environment Institute, and Adjunct Lecturer, Department of Thematic Studies – Environmental Change, Linköping University

Prof. David Schlosberg

Director, Sydney Environment Institute and Professor of Environmental Politics, University of Sydney. Fellow of the Academy of Social Sciences of Australia; Member of Expert Working group on Just Adaptation, Future Earth Australia and the Australian Academy of Science.

Michelle Scobie, PhD

LlB (Hons), LEC, Dipl. Int. Rel.. Senior Lecturer, International Law, Global Environmental Governance, Institute of International Relations. Member of the Scientific Advisory Committee of the Inter-American Institute for Global Change Research. Member of the Oceans Governance Network of the University of the West Indies

Prof. Stacy D. VanDeveer

Professor and Department Chair, Conflict Resolution, Human Security and Global Governance, Mc­Cormack Graduate School of Policy and Global Studies, University of Massachusetts Boston


Meet the scholars from around the world who are the signatories of our Open Letter calling for an International Non-Use Agreement on Solar Geoengineering.

Prof. John Barry

Professor of Green Political Economy, co-director, Centre for Sustainability, Equality and Climate Action at Queen’s University Belfast; co-chair of the Belfast Climate Commission and member of the UK Parliament’s Committee on Climate Change

Prof. Frans Berkhout

Assistant Principal, King’s Climate & Sustainability; Professor of Environment, Society and Climate, Department of Geography at King’s College London.

Prof. Steven Bernstein

Distinguished Professor of Global Environmental and Sustainability Governance, University of Toronto Co-Director, Environmental Governance Lab, Munk School of Global Affairs and Public Policy Co-Editor, Global Environmental Politics

Hon. Prof. Peter Bridgewater

Honorary Professor, Centre for Heritage and Museum Studies, Australian National University; Fellow of the International Science Council; Technical Adviser Australian Delegation to IPBES

Prof. Eduardo S. Brondizio

Distinguished Professor, Department of Anthropology. Director, Center for the Analysis of Social-Ecological Landscapes (CASEL), Senior Research Fellow, The Ostrom Workshop in Political Theory and Policy Analysis, Indiana University Bloomington

Prof. Jennifer Clapp

Professor and Canada Research Chair, University of Waterloo; Vice-Chair, Steering Committee of the High Level Panel of Experts on Food Security and Nutrition (UN Committee on World Food Security); Member, International Panel of Experts on Sustainable Food Systems; Fellow of the Royal Society of Canada; Contributing author to IPCC 6th Assessment Report

Prof. Wolfgang Cramer

Professor, Director of CNRS, Mediterranean Institute for Biodiversity and Ecology (IMBE), Member of Academie d’Agriculture de France

Dr. Arthur Lyon Dahl

President, International Environment Forum; retired Deputy Assistant Executive Director, UNEP, and Coordinator, UN System-Wide Earthwatch; Visiting Professor, European Center for Peace and Development

Prof. Robyn Eckersley

Redmond Barry Distinguished Professor in the Discipline of Political Science, School of Social and Political Sciences at the University of Melbourne and a Fellow of the Academy of the Social Sciences in Australia

Prof. Joanna D. Haigh, FRS

Emeritus Professor of Atmospheric Physics, Former Co-Director of the Grantham Institute on Climate Change and Former Head of Department of Physics at Imperial College London; Fellow of the Royal Society; Former President of the Royal Meteorological Society; Lead Author of the IPCC Third Assessment report.

Prof. Paul Harris

Chair Professor of Global & Environmental ​Studies, The Education University of Hong Kong

Prof. Anna-Katharina Hornidge

Director, German Development Institute; Professor of Global Sustainable Development, Bonn University; Member, German Advisory Council on Global Change

Prof. Dale Jamieson

Founding Director of Environmental Studies and Professor of Environmental Studies and Philosophy, New York University; Founding Director Center for Environmental and Animal Protection

Prof. Jean Jouzel

Director of research (emeritus) at CEA (The French Alternative Energies and Atomic Energy Commission)

Prof. Richard J. T. Klein

Senior Research Fellow, Stockholm Environment Institute, and Professor of Geography, Climate Policy and Development, Linköping University; six-times IPCC lead or coordinating lead author

Prof. Dr. Ingolf Kühn

Head of Department Community Ecology at Helmholtz Centre for Environmental Research – UFZ and Professor for Macroecology, Martin Luther University Halle-Wittenberg

Prof. Hervé Le Treut

Senior researcher CNRS (Centre National de la Recherche Scientifique, France), Professor at Ecole Polytechnique, Member of the French Academy of Sciences, Member of the Academia European

Prof. Michael E. Mann

Presidential Distinguished Professor, Director of Penn Center for Science, Sustainability, and the Media, University of Pennsylvania;
Co-author to IPCC 3rd Assessment Report

Prof. Lyla Mehta

Professor Institute of Development Studies at the University of Sussex and Norwegian University of Life Sciences; Lead Author of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services; Former Team leader of the UN High Level Panel of Experts on Food Security and Nutrition

Prof. Dr. Sebastian Oberthür

Professor of Environment and Sustainable Development, Vrije Universiteit Brussel, and Professor of Environmental Policy and Law, University of Eastern Finland

Prof. Lennart Olsson

Lund University Centre for Sustainability Studies (LUCSUS), IPCC Coordinating Lead Author in Assessment Report 5 (Ch. 13) and IPCC Special Report on Climate Change and Land (Ch. 4)

Prof. Hiroshi Ohta

Professor and Director, Institute of Global Governance at the Organization of Regional and Inter-regional Studies, Waseda University, and Councilor, Japan Association of International Relations (2020-2022)

Prof. William E. Rees, FRSC

Professor Emeritus and former Director, University of British Columbia School of Community and Regional Planning; Founding member and former President of the Canadian Society for Ecological Economics; Fellow of the Post-Carbon Institute; recipient of a 2012 Blue Planet Prize.

Prof. Philip J. Sakimoto

Professor of the Practice in Physics and Astronomy, and Director, Minor in Sustainability, University of Notre Dame; Former
Program Manager, Space Science Education and Public Outreach Program, National Aeronautics and Space Administration (NASA)

Prof. José Sarukhán Kermez

Emeritus Professor, Institute of Ecology, UNAM.
President of Diversitas, UNESCO.
Member of IPCC, TAR 3.
National Coordinator of the Mexican National Commission for the Knowledge and Use of Biodiversity (CONABIO).
Member of UNESCO’s Commission of Ethics of Science and Technology.

Prof. Roberto Schaeffer

Full Professor of Energy Economics, Universidade Federal do Rio de Janeiro.
Five-times IPCC Lead or Coordinating Lead Author.
Member of the Brazilian Academy of Sciences.

Prof. Mary Scholes

Professor of Systems Analysis, University of the Witwatersrand Fellow, African Academy of Sciences, Fellow the Royal Swedish Academy (Forestry and natural resources section), Member of the South African Academy of Sciences, Fellow of the Royal Society of South Africa

Prof. Johan Schot

Professor of Global History and Sustainability Transitions, Utrecht University Centre for Global Challenges and part of the Economic and Social History group, Utrecht University

Prof. Dr. Sonia I. Seneviratne

Full Professor, ETH Zürich, Institute for Atmospheric and Climate Sciences
IPCC Coordinating Lead Author and Lead Author of past reports (AR6, AR5)
IPCC Working Group I Vice-chair (AR7)

Prof. Dr. Josef Settele

Coordinating Lead Author in IPCC AR5; Coordinating Lead Author in IPBES Pollination Assessment; Co-Chair of IPBES Global Assessment.
Head of Department of Conservation Biology and Social-Ecological Systems at the Helmholtz Centre for Environmental Research – UFZ, Germany.
Professor of Ecology at the Martin-Luther-University Halle-Wittenberg, Germany; adj. Prof. at the University of the Philippines in Los Banos.

Prof. Clifford Shearing

Professor Emeritus, Law Faculty, University of Cape Town, Visiting Professorial Fellow, Faculty of Law, University of New South Wales, Professeur associé, École de criminologie, Université de Montréal

Prof. Christina Voigt

Professor at the Department of Public and International Law, University of Oslo; Co-chair of the Paris Agreement Implementation and Compliance Committee; Chair of the IUCN World Commission on Environmental Law

Dr. Margaretha Wewerinke-Singh

Associate Professor of Sustainability Law at the University of Amsterdam, The Netherlands; Adjunct Senior Lecturer in Environmental Law, Pacific Centre for Environment and Sustainable Development, The University of the South Pacific, Fiji

Prof. Oran Young

Distinguished Professor Emeritus, Bren School of Environmental Science & Management, University of California, Santa Barbara, Co-director of the Program on Governance for Sustainable Development at the Bren School, Director of the Institute of Arctic Studies, Adjunct Professor of Political Science at the University of Tromsø in Norway

See below the scientists and scholars who have signed our call for an International Non-Use Agreement on Solar Geoengineering (non-alphabetical order).

Prof. Udo E. Simonis

Professor Emeritus at the Berlin Social Science Center (WZB); Honorary member of the Potsdam Institute for Climate Impact Research (PIK)

Dr. Adeniyi Asiyanbi

Assistant Professor, Department of Community Culture and Global Studies, University of British Columbia Okanagan

Dr. Danny Marks

Assistant Professor of Environmental Politics and Policy in the School of Law and Government, Dublin City University

Dr. Yves Dandonneau

Laboratoire d’Océanographie et du Climat (LOCEAN), Institut de recherche en sciences de l’environnement (IPSL) (retired)

Dr. Pierre Chevallier

Director of Research Emeritus, Laboratoire HydroSciences Montpellier (CNRS, IRD, Univ. Montpellier, Ecole Mines-Telecom Alès)

Dr. Sabrina Schulz

Executive Director, Sustainable Development Solutions Network (SDSN) Germany; Germany Institute for Development (DIE)

Prof. Erik Paredis

Associate Professor, Transition Governance and Circular Economy, Faculty of Political and Social Sciences, Ghent University

Rens Chazottes

Ph.D. candidate, Social and Political Sciences Department, European University Institute

Dr. Steffen Bauer

Senior Researcher and Head of Klimalog, Deutsches Institut für Entwicklungspolitik / German Development Institute (DIE)

Dr. Anneleen Kenis

Senior Research Fellow (FWO) at University of Leuven and Ghent University; Visiting Scholar at University of Cambridge

Dr. Liz Allen

Research Development Officer and lecturer, Northeastern University; Board member, Sustainable Consumption Action and Research Initiative

Dr. Amy Janzwood

SSHRC Postdoctoral Fellow, Department of Political Science, The University of British Columbia

Dr. Gileard Minja

Researcher, Lecturer and Consultant, Department of Agriculture, Earth and Environmental Sciences, Mwenge Catholic University

Dr. Xiao-Shan Yap

Founder at Earth-Space Sustainability Research Initiative; Lead Senior Researcher at EPFL Space Center; Assistant Prof at Utrecht University

Prof. Dr. Jaap Spier

Former Advocate-General in the Supreme Court of the Netherlands, Extraordinary Professor of Global Challenges, University of Stellenbosch