Open Letter to Heads of Government of the G-20 from Scientists and Scholars on Nuclear for Climate Change

President Emmanuel Macron

President of the French Republic

55 Rue du Faubourg Saint-Honoré

75008 Paris, France


Prime Minister Mark Rutte

President Mauricio Macri

The Honourable Scott Morrison

His Excellency Michel Miguel Elias Temer Lulia

The Right Honourable Justin Trudeau

President Xi Jinping

His Excellency Donald Tusk

Chancellor Angela Merkel

Prime Minister Narendra Modi

President Joko Widodo

President Sergio Mattarella

His Excellency Shinzō Abe

President Enrique Peña Nieto

President Vladimir Putin

King Salman bin Abdulaziz Al Saud

His Excellency Cyril Ramaphosa

President Moon Jae-in

President Recep Tayyip Erdoğan

The Right Honourable Theresa May

President Donald Trump

Dear President Macron,

We are writing as scientists, scholars, and concerned citizens to warn you of a persistent anti-nuclear bias in the recent Intergovernmental Panel on Climate Change (IPCC) report on keeping global temperatures from rising 1.5 degrees above pre-industrial levels.[1]

While many of the scenarios in the IPCC report call for the expanded use of nuclear energy, the report nonetheless repeats misinformation about nuclear energy, contrasts nuclear negatively to renewables, and in some cases, suggests an equivalency with fossil fuels.

While IPCC authors note that public fears of nuclear are an obstacle to its diffusion, in several instances they reinforce unfounded fears. Please consider the following:

  • Nuclear is the safest way to make reliable electricity[2] and has saved over 1.8 million lives that would have been lost prematurely to deadly air pollution.[3]

  • Nuclear plants produce just 12 grams of carbon dioxide per kilowatt-hour (kWh) as compared to coal plants, natural gas plants, biomass plants, and solar farms which produce 820, 490, 230, and 48 grams of CO2/kWh, respectively, as used in the IPCC’s own publications.[4]

  • Of humankind’s exposure to ionizing radiation, 88% comes from natural causes and 12% from human-made causes with just 0.04% from nuclear plant emissions.[5]

  • The increased risk of mortality from living in a large city, where concentrations of air pollution are high, is 2.8 times greater than the increased risk of mortality for Chernobyl clean-up workers who received the highest levels of radiation exposure.[6]

  • There is a consensus among leading radiation scientists that nobody should have been relocated after the accident at Fukushima Daiichi because the evacuation caused far more harm than the radiation that escaped from the plant could have.[7]

  • Because uranium has an energy density one to three million times higher than coal, nuclear plants require the fewest fuel and material inputs, giving them the smallest mining and land use impact of all energy sources.[8]

  • While nuclear provided 11% of electricity globally last year, solar and wind provided only 1.3% and 3.9%.[9]

  • Because of their inherently intermittent nature, solar and wind energy sources rarely substitute on a one-to-one basis for fossil fuels and must be backed up by fossil fuels, hydroelectric dams, or some other form of large-scale storage.[10]

  • The peak deployment of nuclear energy around the world has occurred more than 10 times faster than the peak deployment of solar and wind, according to a 2016 study published in the journal Science.[11]

The above facts are crucial for putting the role of nuclear in context and yet were either not included in the IPCC report or were insufficiently highlighted.

Moreover, in several instances IPCC authors make misleading claims about nuclear power including:

  • An alleged debunking of the above-mentioned 2016 study in Science through the use of a 2018 study published in a journal[12] with an impact factor of just 10 percent of that of Science;

  • The suggestion that building new nuclear plants must be a slow process[13] despite evidence from the recent past that nuclear capacity can be installed very rapidly when required[11];

  • A statement[14] suggesting a connection between “nuclear installations” and “childhood leukemia,” and no mention of recent research finding higher radiation exposure from coal plants and the manufacturing of solar panels than from nuclear.[15] While the authors acknowledge that there is “low evidence/low agreement” to support their claim, in reality there is no valid evidentiary support for it and the supposed connection has been thoroughly dismissed in the literature[16];

  • A claim that nuclear power “can increase the risks of proliferation”[17] and that the "use of nuclear power poses a constant risk of proliferation"[18] even though no nation in history has ever created a nuclear weapon from civilian nuclear fuel under inspection by the International Atomic Energy Agency;

  • A claim that nuclear has “mixed effects for human health when replacing fossil fuels,”[19] which is contradicted by the large body of scientific research, cited above, showing that nuclear saves lives;

  • Repeated concerns raised about nuclear waste[20] without acknowledgment or clarification that spent fuel is safely contained, usually on site, nor any mention of the waste from other low-carbon energy sources, including solar panels, which contain toxic metals including lead, chromium, and cadmium, and which in most of the world lack safe storage or recycling.[21]

Such fear-mongering about nuclear has serious consequences. As IPCC itself acknowledges, public fears of nuclear are behind the technology’s slower-than-desirable development.[22] Equally troubling, public fear of nuclear drove the panicked over-reaction to past nuclear accidents, including mass evacuations, which health experts agree had a far larger negative impact on human health than the low-levels of radiation that escaped from the plants.[23]

Where nuclear has proven capable of providing cheap and reliable zero-carbon power to large modern economies from France to Canada to Sweden, solar and wind, which IPCC treat more favorably, have not, in large measure because they require a constant source of back-up energy. And where IPCC report authors offer “policy interventions” to mitigate the challenges of scaling up solar and wind, they do not offer similar policy interventions for nuclear.

While we are gravely disappointed by the double standard with which the IPCC treated nuclear and other low-carbon energy sources, we are hopeful that you, as the head of state of a large modern economy, can rectify such misinformation through your words and actions.

We strongly encourage you to do everything in your power to speak out for nuclear and expand its share of electricity production, heating, and transport, including shipping production, to achieve the intertwined goals of climate change mitigation, pollution reduction, and poverty alleviation.


Tom Wigley, Climate and Energy Scientist, National Center for Atmospheric Research, Boulder, Colorado

Kerry Emanuel, Professor of Atmospheric Science, Massachusetts Institute of Technology

David Lea, Professor, Earth Science, University of California

Barry Brook, Professor of Environmental Sustainability, University of Tasmania

Paul Robbins, Director, Nelson Institute for Environmental Studies, University of Wisconsin-Madison

Richard Rhodes, author, Pulitzer Prize-winner, The Making of the Atomic Bomb

Gerry Thomas, Professor of Molecular Pathology, Department of Surgery and Cancer, Imperial College London

Philip Thomas, Professor of Risk Management, University of Bristol

Wade Allison, Professor Emeritus of Physics, Oxford University

Joe Lassiter, Professor, Harvard Business School

Peter H. Raven, President Emeritus, Missouri Botanical Garden. Winner of the National Medal of Science, 2001

Andrew Klein, Past President, American Nuclear Society

Mark Lynas, Alliance for Science, Cornell University, author, The God Species, Six Degrees

Bill Lee, Professor of Nuclear Engineering, Imperial College London and Bangor University, U.K.

Steven Pinker, Harvard University, author of Better Angels of Our Nature

Michelle Marvier, Professor, Environmental Studies and Sciences, Santa Clara University

Tony Roulstone, Department of Engineering, Cambridge University

Martin Lewis, Department of Geography, Stanford University

Simon Henry Connell, Department of Mechanical Engineering Science, University of Johannesburg

Joshua S. Goldstein, Professor Emeritus, International Relations, American University

Malcolm Grimston, author of The Paralysis in Energy Decision Making, Honorary Research Fellow, Imperial College London

Robert Coward, Past President of ANS

David Dudgeon, Chair Professor of Ecology & Biodiversity, School of Biological Sciences, The University of Hong Kong

Gwyneth Cravens, author of Power to Save the World

Robert Stone, filmmaker, “Pandora’s Promise”

Myrto Tripathi, Voices for Nuclear, France

Staffan Qvist, co-author, A Bright Future (PublicAffairs 2019)

Norris McDonald, President, Environmental Hope & Justice

Valerie Gardner, founder, Climate Coalition

Carl Page, co-founder, Anthropocene Institute

Kirsty Gogan, Executive Director, Energy for Humanity

Michael Shellenberger, Time Magazine “Hero of the Environment,” President, Alan Medsker, Environmental Progress

Steve Kirsch, CEO, Token

Rauli Partanen, Ecomodernist Society (Finland)

Olguita Oudendijk, ECOMODERNISME NL, (Ecomodernist Society, Netherlands)

Steven Savarense, Saving Our Planet (France)

Kristin Zaitz and Iida Ruishalme, Mothers for Nuclear (U.S. and Switzerland)

Rainer Klute, Nuklearia, Germany

Rebecca Lohfert Boas, Ren Energi Oplysning (Denmark)

Amardeo Sarma, co-founder of the German Ecomodernist Society Ökomoderne e.V.

Robin Thiedmann, Chairman of the German Partei der Humanisten


[1] “Global Warming of 1.5 degrees,” IPCC, October 2018.

[2] Markandya, M., and Wilkinson, P., “Electricity Generation and Health,” Lancet, September 15, 2007. Kearns, J. O., Thomas, P. J., Taylor, R. H., Boyle, W. J. O., 2012, "Comparative Risk Analysis of Electricity Generating Systems Using the J-Value Framework", Proc. IMechE Part A: J. Power and Energy, Vol. 226, pp. 414 – 426, May.

[3] Kharecha, P.A., and J.E. Hansen, “Prevented mortality and greenhouse gas emissions from historical and projected nuclear power,” Environ. Sci. Technol.,2013.

[4] Schlömer, S., et al., “Annex III, Table A, III.2,” Climate Change 2014, IPCC, 2014. 

[5] “Naturally-Occurring Radioactive Materials (NORM),” World Nuclear Association, May 2018.

[6] Smith, J., “Are passive smoking, air pollution and obesity a greater mortality risk than major radiation incidents?” BMC Public Health, 2007.

[7] Thomas, P., et al., “Coping after a big nuclear accident,” Process Safety and Environmental Protection, November 2017.

[8] U.S. Department of Energy, “Quadrennial Technology Review,” Table 10, 2015; Murray, R.L. et al., Nuclear Energy: An Introduction, Elsevier, (7th edition), 2007.

[9] “Statistical Review of World Energy,” BP, 2018.

[10] Clack, C., et al., “Evaluation of a proposal for reliable low-cost grid power with 100% wind, water, and solar,” Proceedings of the National Academy of Sciences, June 27, 2017. Thomas, P. J., 2012, " The limits to wind power and the cost of standby generation", Proc. IMechE Part A: J. Power and Energy, Vol. 226, 514 – 531, June.

[11] Cao, J. et al., “China-U.S. Cooperation to Advance Nuclear Power,” Science, 2016.

[12] Lovins, A., et al., “Relative deployment rates of renewable and nuclear power: A cautionary tale of two metrics,” Energy Research and Social Science, April 2018.

[13] De Conninck et al., " Chapter 4: Strengthening and implementing the global response", Nuclear Energy, p. 4-19, line 23, , IPCC, 2018

[14] Roy, J., et al. “Chapter 5: Sustainable Development, Poverty Eradication and Reducing Inequalities,” p. 52, Table: Row Nuclear/Advanced Nuclear, Column: Disease and Mortality, IPCC, 2018

[15] United Nations Scientific Committee on the Effects of Radiation, “Radiation Exposures from Electricity Generation,” Sources, Effects, and Risks of Radiation of Ionizing Radiation 2016, 2017.

[16] For a recent review, see: Janiak, M. K. (2014). Epidemiological Evidence of Childhood Leukaemia Around Nuclear Power Plants. Dose-Response, 12(3), 349–364.

[17] Roy, J., et al. “Chapter 5: Sustainable Development, Poverty Eradication

and Reducing Inequalities,” Energy Supply: Accelerated Decarbonisation, p. 5-23, line 43, IPCC, 2018

[18] Roy, J., et al. “Chapter 5: Sustainable Development, Poverty Eradication and Reducing Inequalities,” p. 5-57, Table: Row: Nuclear/Advanced Nuclear, Column: Reduce illicit arms trade, IPCC, 2018

[19] Roy, J., et al. “Chapter 5: Sustainable Development, Poverty Eradication and Reducing Inequalities,” Energy Supply: Accelerated Decarbonisation, p. 5-23, line 44, IPCC, 2018.

[20] Roy, J., et al. “Chapter 5: Sustainable Development, Poverty Eradication and Reducing Inequalities,”, p. 5-52, Table: Row: Nuclear/Advanced Nuclear, Column: Disease and Mortality. , IPCC, 2018

[21] Enbar, N. et al., “PV Lifecycle Analysis,” Electric Power Research Institute, 2016; Weckend, S., “End of Life Solar PV Panels,” IRENA, 2016.

[22] De Conninck et al., " Chapter 4: Strengthening and implementing the global response", Nuclear Energy, p. 4-19, line 48, , IPCC, 2018.

[23] International Atomic Energy Agency. (2015). The Fukushima Daiichi Accident: Report by the Director General. Vienna, Austria. Retrieved from