Lesson Plan

The End of the Cold War: Nuclear Winter


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.


  • 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.
  • Social Studies
  • Environment
  • Geography
  • Civics & Government
  • U.S. History
  • World History
  • AP Environmental Science
  • Arms Race
  • Cold War
  • Ronald Reagan
  • U.S. Foreign Policy
  • 1980s America
  • 1990s America
  • The Modern Era (1980-Present)
  • Climate Change
For Teachers

Introducing the Lesson

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.

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?

Lesson Procedure

  • Why did many experts on nuclear weapons and diplomacy regard the early 1980s as the most dangerous period since the Cuban Missile Crisis of 1962? How did Reagan’s election in 1980 cause American nuclear policy to shift?
  • Which do you think is more dangerous: the ongoing proliferation of nuclear weapons, or climate change?
  • Carl Sagan and other scientists played an enormous role in the nuclear freeze movement. Are there other examples in history of scientists who have influenced the public debate over political issues? Should scientists play a greater role in shaping public policy?
  • The video mentioned the idea of geo-engineering, the notion that humans could intentionally change the earth’s climate systems as a way to address climate change. In your lifetime, will we see attempts to geo-engineer a solution to global warming? Do you find that kind of approach intriguing or disturbing?

Additional Resources

TranscriptRetro Report 
“Global Warming Gives Science Behind Nuclear Winter a New Purpose”Retro Report/The New York Times 

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.

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.

Evaluate how historical events and developments were shaped by unique circumstances of time and place as well as broader historical contexts.

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

Theme: America in The World (WOR)

Questions? Tips? Concerns? Reach out to our Director of Education, David Olson: dolson@retroreport.com