Columbia writer promotes nuclear disarmament

In 1983, Cornell University Astronomy Professor Carl Sagan and four other NASA scientists conducted an in-depth study of the possible atmospheric consequences of nuclear war. The study concluded that the gigantic fires caused by nuclear detonations in cities and industrial areas would cause millions of tons of smoke to rise into the Earth’s stratosphere. There the smoke would block most sunlight, causing average temperatures on Earth’s surface to rapidly cool to Ice Age levels.