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We are calling on world leaders to take urgent action on climate change to limit global warming to less than 2 degrees centigrade. Some of the world’s leading thinkers and practitioners have signed this statement. Please join them, add your voice to theirs to call for decisive action on climate change. The message will be presented to world leaders on the occasion of the Climate Leaders’ Summit, convened by UN Secretary-General Ban Ki-moon at the United Nations, New York City, on September 23, 2014.


Total signatures on this letter: 6,626


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2degrees

Message on Climate Change to World Leaders

Download the letter here.

Human-induced climate change is an issue beyond politics. It transcends parties, nations, and even generations. For the first time in human history, the very health of the planet, and therefore the bases for future economic development, the end of poverty, and human wellbeing, are in the balance. If we were facing an imminent threat from beyond Earth, there is no doubt that humanity would immediately unite in common cause. The fact that the threat comes from within – indeed from ourselves – and that it develops over an extended period of time does not alter the urgency of cooperation and decisive action.

The world has agreed to limit the mean temperature increase to less than 2-degrees Centigrade (2°C). Even a 2°C increase will carry us to dangerous and unprecedented conditions not seen on Earth during the entire period of human civilization. Various physical feedbacks – in the Arctic, the oceans, the rainforests, and the tundra – could multiply a 2°C temperature increase into vastly higher temperatures and climate disruption. For this reason many scientists and some countries advocate for 1.5°C or even stricter targets.

To give up on the 2°C limit, on the other hand, would be reckless and foolish. We would abandon our remaining chance to stay within a safe operating space for humanity and that of millions of other species. By holding the 2°C limit, we would retain the global option to adopt an even more stringent emission reduction limit in line with evolving scientific knowledge and technological capacities.

The 2°C limit, or an even stronger target, can be met through long-term national strategies and concerted global cooperation. All countries must commit to a deep decarbonization of their energy systems, shifting from high-carbon energy (coal, oil, and natural gas) to low-carbon energy of various kinds (e.g. wind, solar, nuclear, carbon capture and sequestration, known as CCS). Low-carbon electricity plus massive gains in energy efficiency and the electrification of vehicles, heating and cooling systems of commercial as well as residential buildings can lead to a dramatic reduction of carbon-dioxide emissions alongside a growing economy. Changes in lifestyle patterns and urban planning can make another important contribution. The many co-benefits of decarbonization with the deployment of sustainable energy, information and communication technologies will include cleaner air and water, enhanced biodiversity, and security of domestic renewable energy resources. Targeted efforts are also required to decarbonize key industries. Finally, countries need to curb greenhouse gas emissions resulting from agriculture, livestock, and land-use change, such as deforestation. They must also manage and restore ecosystems to ensure they can serve as a significant net sink for greenhouse gas emissions.

The technological transition during the first half of the 21st century is within reach, especially in light of massive advances in knowhow in recent years. In many parts of the world and in some contexts, solar and wind power are already at “grid parity.” Large-scale deployment of electric vehicles, carbon-capture and sequestration, next-generation nuclear power plants for those countries deploying nuclear power, and other low-carbon energy technologies are all within reach. They can be pushed to commercial readiness and large-scale deployment through concerted public and private programs of research, development, demonstration, and diffusion (RDD&D) on a global scale.

We have nearly exhausted the Earth’s carbon budget, which measures the cumulative emissions of CO2 that will likely keep the planet within the 2°C limit.  Only through a drastic reduction of carbon emissions between now and 2050, en route to a zero-net emission economy in the second half of the century, can we meet the challenge of remaining below 2°C. Yet, deep decarbonization can be accomplished.  As President John F. Kennedy said a half-century ago, “We choose to go to the moon in this decade and do the other things, not because they are easy, but because they are hard, because that goal will serve to organize and measure the best of our energies and skills…”

In our time, humanity again must choose, this time to save our planet from shortsightedness, greed, and apathy to avoid catastrophic climate change. This time too, we must organize and measure the best of our energies and skills to stay within 2°C. We call upon you, world leaders, to recognize the gravity of the situation, and to call upon all of us to rise to the occasion. We owe nothing less to ourselves, to future generations, and to Earth itself.

Founding Signatories:

(* denotes members of the SDSN Leadership Council)

Irene Agyepong, Regional Director, Health for Greater Accra*

HSC Prince Albert II, Prince Monaco*

Muskdad A. Al-Khateeb, Head, Department of Sustainable Development, Enrironment Research Center, University of Technology, Baghdad

François Anctil, Directeur, Institut Hydro-Quebec en Environnement, Développement et Société

Muhammad Hasan Ali Baig, Hyperspectral Remote Sensing Laboratory (HRS), Institute of Remote Sensing and Digital Earth (RADI)

Nirupam Bajpai, Director, Columbia Global Centers | South Asia

Belay Begashaw, Director, Columbia Global Center, Nairobi*

Frances Beinecke, President, Natural Resources Defense Council (NRDC)*

Joseph Bell, Hogan Lovells, Washington*

Abdullahi Mohammed Bello, Federal University, Kashere, Gombe-Nigeria

Alan Bernstein, President and Chief Executive Officer, Canadian Institute for Advanced Research (CIFAR)

David Berry, Founder, Joule Unlimited*

Gianluca Breghi, Managing Director, Fondazione Achille Sclavo

Carlo Carraro, Rector, Ca’ Foscari University of Venice

Joshua Castellino, Dean, Law School, University of Middlesex*

Maurizio Cellura, Full Professor, Dipartimento di Energi, Ingegneria dell’Informazione e Modelli Matematici (DEIM), University of Palermo

Madhav Chavan, Co-founder and CE-President, Pratham, India*

Brendan Cox, Director of Policy and Advocacy, Save the Children

Patrick Criqui, Head of EDDEN Research Group, CNRS-University of Grenoble

Yacine Dansokho, General Manager, Environmental Science and Metrology Institute, Senegal

Sir Partha Dasgupta, Professor Emeritus, University of Cambridge, United Kingdom

Richard Deckelbaum, Director, Institute of Human Nutrition, Columbia University

Ketut Gede Dharma Putra, Chairman, Center for Sustainable Development Udayana University of Bali

Leclère Diffo, President, Green Horizon Cameroon

Bineta Diop, President, Femmes Africa Solidarité*

Eugenio Di Sciascio, Rector, Politecnico di Bari

Achim Dobermann, Director, Rothamsted Research*

May East, Chief Executive, CIFAL Scotland

Kokunre Eghafona, Sustainable Development Desk Officer, University of Benin, Benin City, Nigeria

Üstün Ergüder, Director, SDSN Turkey

José María Figueres, CEO, Carbon War Room*

Maria Freire, President and Executive Director, Foundation for the National Institutes of Health (FNIH)*

Michael Gerrard, Professor, Columbia University Law School

Dave Griggs, Director, Monash Sustainability Institute, Monash University

Jennifer Gross, Member of the Board, Gross Family Foundation

Zakri Abdul Hamid, Chair, International Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES)*

James Hansen, Former Director, NASA Goddard Institute for Space Studies*

Tom Heller, Executive Director, Climate Policy Initiative*

Feyera Dinsa Hundessa, Director, Academic Programs Development and Admissions, Haramaya University

Ivano Iannelli, CEO, Dubai Carbon Centre of Excellence

Pavel  Kabat, Director, International Institute for Applied Systems Analysis (IIASA)*

Joan  Kaufman, Director, Columbia Global Centers East Asia

Georg Kell, Executive Director, UN Global Compact

Mark Kenber, CEO, The Climate Group

Geoffrey Kent, Founder, Chairman and CEO, Abercrombie & Kent Group of Companies*

Niclas Kjellström-Matseke, Managing Director, Novamedia Swedish Postcode Lottery*

Israel Klabin, Founder and Executive Director, Brazilian Foundation for Sustainable Development*

Fred Krupp, President, Environmental Defense Fund

Felipe Larraín, Director, Centro Latinoamericano de Políticas Económicas y Sociales (CLAPES-UC)*

Richard Layard, Director. Well-Being Programme Centre for Economic Performance London School of Economics*

Frannie Léautier, Partner and Chief Executive Officer, Mkoba Private Equity Fund*

Yuan Lee, Former President, Academia Sinica and Nobel Prize Laureate*

Klaus Leisinger, President, Stiftung Globale Werte Allianz*

Corinne Le Quere, Director Tyndall Center for Climate Change Research, University of East Anglia

Gordon Liu, Director, Peking University China Center for Health Economic Research (CCHER)*

Jane Lubchenco, Oregon State University, Corvallis*

Søren Winther Lundby, Chief Executive Officer, Global Citizen

Michael MacCracken, Chief Scientist for Climate Change Programs, Climate Institute

Arun Majumdar, Energy Initiatives Lead, Google Inc*

Michael Mann, Professor and Director of the Earth System Science Center, Pennsylvania State University

Julia Marton-Lefèvre, Director General, IUCN*

Vladimir A. Mau, Rector, Russian Presidential Academy of National Economy and Public Administration*

Dirk Messner, Director, German Development Institute

Chiara Mio, Rector’s Delegate on Environmental Sustainability and University Social Responsibility, Ca’ Foscari University of Venice

Angus. D. Munro, Vice-President, Research, Development and Policy, University of Cambodia

Shahid Naeem, Director, Earth Institute Center for Environmental Sustainability*

Claude Nahon, Executive Vice President for Sustainable Development, EDF*

Sunita Narain, Director General, Centre for Science and Environment

Tolera Negassa, Teacher Development Program Coordinator, Adama Science and Technology University

Rebecca Nelson, Professor, Cornell University*

Cherie Nursalim, Executive Director, GITI Group*

Ngozi Ifeoma Odiaka, Professor, University of Agriculture Makurdi, Benue State, Nigeria

Ikenna Onyido, Founder and Director, Centre for Sustainable Development, Nnamdi Azikiwe University, Nigeria*

Mari Pangestu, Minister of Tourism and Creative Industries, Indonesia*

George Papandreou, Former Prime Minister, Greece*

Paul Polman, CEO, Unilever*

Labode Popoola, Professor, Forest Economics & Director, Centre for Sustainable Development, University of Ibadan, Ibadan

Alberto Posso, Senior Lecturer Economics, RMIT

Ketut Gede Dharma Putra, Chairman, Center for Sustainable Development, Udayana University of Bali

V (Ram) Ramanathan, Professor, SCRIPPS Institution of Oceanography, UCSD, California

Rino Rappuoli, Global Head, R&D Novartis Vaccines and President, Fondazione Achille Sclavo

Michael Raupach, Director, Climate Change Institute, Australian National University

Srinath Reddy, President and Executive Director, Public Health Foundation of India*

Irwin Redlener, Director, National Center for Disaster Preparedness, Earth Institute, Columbia University

Aromar Revi, Director, Indian Institute for Human Settlements*

Angelo Riccaboni, Rector, University of Siena, Italy*

Johan Rockström, Executive Director, Stockholm Resilience Center*

Jonathan Rose, President, Jonathan Rose Companies

Cynthia Rosenzweig, Professor, Earth Institute, Columbia University*

Angelo Antonio Russo, Director, PHD Program in Economics and Management of Natural Resources, Associate Professor of Management, LUM University

Roberto Russo, President, International Federation for Sustainable Development and Fight to Poverty in the Mediterranean-Black Sea

Jeffrey D. Sachs, Director, Earth Institute, Columbia University Director of the SDSN*

Jeffrey Sayer, Director, Development Practice Programme, James Cook University

Marcello Scalisi, Executive Director, UNIMED-Mediterranean Universities Union

Hans Joachim Schellnhuber, Director, Potsdam Institute for Climate Impact Research (PIK)

Josette Sheeran, President, Asia Society*

Mark Stafford Smith, Chair, Future Earth Science Committee

Marcelo Sanchez Sorondo, Chancellor, The Pontifical Academy of Science

Anna Skarbek, Executive Director, ClimateWorks Australia

Will Steffen, Adjunct Professor, Fenner School of Environment and Society, The Australian University

Lord Nicholas Stern, IG Patel Professor, Chair of Grantham Institute, London School of Economics

Pavan Sukhdev, Founder and Chief Executive Officer, GIST Advisory*

Mohd Yusoff Sulaiman, President and CEO, MIGHT

Jatna Supriatna, Chairman, University of Indonesia Research Center of Climate Change

Mark Tercek, President and CEO, The Nature Conservancy

Jean-Philippe Thomas, Executive Secretariat, ENDA Tiers Monde

John Thwaites, Chair, Monash Sustainability Institute*

Lena Treschow Torell, Chairman, MISTRA*

Laurence Tubiana, Professor, Sciences Po (Paris) and Columbia University, Co-Chair of the SDSN Leadership Council*

Ted Turner, Founder and Chairman, United Nations Foundation*

Auwalu Uba, Abubakar Tafawa Balewa University, Bauchi

Hans Vestberg, President and CEO, Ericsson Group*

Virgilio Viana, Director General, Amazonas Sustainability Foundation*

Martin Visbeck, Chair in Physical Oceanography, GEOMAR – Helmholtz Centre for Ocean Research Kiel & Kiel University*

Patrick Paul Walsh, Chair of the Academic Steering Group, Global MDP Association

Kevin Watkins, Director, Overseas Development Institute

Robert Watson, former Chair of the IPCC

Daniel Wiener, Chairman, Global Infrastructure Basel Foundation

E.O. Wilson, Emeritus, Harvard University

John Wiseman, Deputy Director, Melbourne Sustainability Society Institute, University of Melbourne

Xue Lan, Professor and Dean, School of Public Policy and Management, Tsinghua University, Co-Chair of the SDSN Leadership Council*

Hirokazu Yoshikawa, Professor, New York University*

Soogil Young, Professor, KDI School of Public Policy and Management*

Bill Zhou, Executive Director, SUSDS

Hania Zlotnik, Former Director, UN Population Division*