Could We Geoengineer Ourselves Out of Climate Change?

Is geo-engineering the climate an answer to global warming? Cold War science has some lessons.

In 1983, scientists gave the world a new reason to fear nuclear war. It had long been assumed that the immediate, direct effects of a nuclear blast would cause a devastating loss of life, and that radioactive fallout would linger. But these scientists stressed that smoke from nuclear-ignited cities might affect something far more remote — the climate around the globe.

What they found was harrowing. Their models showed that smoke from burning cities and forests could loft high into the atmosphere, shrouding the world in a twilight at noon. Freezing temperatures would kill crops, causing mass starvation and social unrest, and possibly lead to the extinction of mankind.

Called Nuclear Winter, this theory became a heated scientific topic, a pawn in Cold War brinksmanship and a lesson in how scientific understanding changes over time. But decades after detente finally ended the Cold War, it is clear that Nuclear Winter continues to raise new questions — not only about the devastation that would follow nuclear war, but also more fundamental ones about man’s ability to alter the earth’s climate, for both good and ill.

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Related: Global Warming Gives Science Behind Nuclear Winter a New Purpose by Clyde Haberman

Additional Resources:

“Nuclear Winter: Global Consequences of Multiple Nuclear Explosions” by Carl Sagan, et al., 1983

“Long-term Biological Consequences of Nuclear War” by Paul R. Ehrlich, et al., 1983

“The Soviet Approach to Nuclear Winter” CIA Interagency Intelligence Assessment, 1984

“The Effects on the Atmosphere of a Major Nuclear Exchange” Committee on the Atmospheric Effects of Nuclear Explosions, National Research Council, 1985

“Global Atmospheric Effects of Nuclear War,” Energy and Technology Review, 1985

“Nuclear Winter Reappraised” by Starley L. Thompson and Stephen H. Schneider, 1986

“Atmospheric and Climatic Consequences of a Major Nuclear War: Results of Recent Research” by G. S. Golitsyn, and M. C. MacCracken, 1987

“Nuclear Winter: Science and Politics” by Brian Martin*, 1988*

“Nuclear Winter Theorists Pull Back” by Malcolm W. Browne, 1990

“Climate and Smoke: An Appraisal of Nuclear Winter” by Carl Sagan et al., 1990

“Nuclear Winter in the Post-Cold War Era” by Carl Sagan and Richard P. Turco, 1993

“Nuclear Winter Revisited with a Modern Climate Model and Current Nuclear Arsenals: Still Catastrophic Consequences” by Alan Robock, Luke Oman, and Georgiy L. Stenchikov, 2007

Interactive comment on “Atmospheric effects and societal consequences of regional scale nuclear conflicts and acts of individual nuclear terrorism” by O. B. Toon et al. By M. MacCracken, 2007

Interactive comment on “Climatic consequences of regional nuclear conflicts” by A. Robock et al. By M. MacCracken, 2007

“Environmental Consequences of Nuclear War” by Owen B. Toon, Alan Robock, and Richard P. Turco, 2008

“Nuclear winter was and is debatable” by Russell Seitz, July 2011

Previous versions
At Retro Report, we update our journalism as news unfolds. Here are the previous published versions of this story.
For teachers
  • Producer: Kit R. Roane
  • Producer: Sarah Weiser

For Educators


This 12-minute video shows students how the U.S.-Soviet nuclear escalation of the 1980s gave rise to a nationwide nuclear freeze movement that challenged assumptions that had for decades guided the American approach to the Cold War. Focusing on the scientific debate over whether any nuclear exchange would be sufficient to trigger a global climate catastrophe, the video helps students draw a line between past fears of a nuclear winter and current fears of a climate crisis. The video gives context for nuclear tensions in the Cold War’s last decade, and can set up an engaging classroom discussion about the connections between the ways Americans confronted the threat of nuclear proliferation in the 1980s, and how they are responding to the threat posed by climate change today.

Background reading

In the 1980s, the nuclear arms race between the U.S. and the Soviet Union gave rise to a nationwide movement to stop what many saw as a rush to oblivion. The worry expressed by Carl Sagan and other scientists was that any exchange of nuclear weapons would trigger a global catastrophe that would plunge the world into a permanent winter, and perhaps exterminate mankind.

They predicted that fires set off by a nuclear war would send up enough smoke to block out the sun, dooming earth and destroying all sources of food. The concept of a nuclear winter was soon backed by the National Academy of Sciences, and even the Pentagon. Ultimately, it steered Cold War strategy.

The concerns eventually reached President Ronald Reagan and Soviet General Secretary Mikhail Gorbachev, who reached an historic agreement to limit nuclear weapons in 1987.

As climate modelling improved over the years, the initial predictions for a nuclear winter were toned down. But the concept eventually entered the national conversation about climate change.

Today, scientists wonder if inducing a nuclear winter-like effect might help reduce global warming. Perhaps a cloud of sulfate particles could be dispersed into the stratosphere, some have suggested, to partially obscure the sun, deflect sunlight and help cool the earth.

This idea, known as geo-engineering, is intriguing, but it’s not without controversy. Anything built by humans can fail.

Lesson Plan 1: The End of the Cold War: Nuclear Winter

Students will learn how a scientific theory of “nuclear winter” shifted the debate over nuclear weapons in the 1980s, and how that hypothesis connects to the 21st century challenge of climate change.

  • How the heightened tensions over nuclear weapons in the last decade of the Cold War led to a nuclear freeze movement within the United States.
  • How scientists’ predictions of a nuclear winter affected the geo-political calculations of both the United States and the Soviet Union.
  • How the science behind the concept of a nuclear winter is linked to studies of geo-engineering as a potential solution for global warming.
Essential questions
  • What political and military aspects of the Cold War in the early 1980s contributed to the growth of the nuclear freeze movement?
  • What was the theory of nuclear winter? According to the projections offered by leading scientists, how would a nuclear winter affect the planet?
  • How did fears of a nuclear winter affect the thinking of leaders and policy makers in the U.S.? In the Soviet Union?
  • To what extent was the nuclear winter theory accurate?
  • Common Core State Standards
    • CCSS.ELA.LITERACY.RH.11-12.7:Integrate and evaluate multiple sources of information presented in diverse formats and media (e.g., visually, quantitatively, as well as in words) in order to address a question or solve a problem.
    • CCSS.ELA.LITERACY.RI.11-12.3:Analyze a complex set of ideas or sequences of events and explain how specific individuals, ideas, or events interact or develop over the course of a text.
  • National Council for the Social Studies C3 Framework
    • D2.His.1.9-12.Evaluate how historical events and developments were shaped by unique circumstances of time and place as well as broader historical contexts.
  • AP U.S. History
    • Topic 9.3: The End of The Cold War

      Skill 1.B: Explain a historical concept, development or process.

      Theme: America in The World (WOR)

  • AP Environmental Science
    • Unit 9: Global Change