Dr. Sagan discussed his new book, A Path Where No Man Thought, in which he reviews the threat of nuclear winter and the arms race.
watch via C-SPAN Video Library
by Carl Sagan
Except for fools and madmen, everyone knows that nuclear war would he an unprecedented human catastrophe. A more or less typical strategic warhead has a yield of 2 megatons, the explosive equivalent of 2 million tons of TNT. But 2 million tons of TNT is about the same as all the bombs exploded in World War II — a single bomb with the explosive power of the entire Second World War but compressed into a few seconds of time and an area 30 or 40 miles across …
In a 2-megaton explosion over a fairly large city, buildings would be vaporized, people reduced to atoms and shadows, outlying structures blown down like matchsticks and raging fires ignited. And if the bomb were exploded on the ground, an enormous crater, like those that can be seen through a telescope on the surface of the Moon, would be all that remained where midtown once had been. There are now more than 50,000 nuclear weapons, more than 13,000 megatons of yield, deployed in the arsenals of the United States and the Soviet Union — enough to obliterate a million Hiroshimas.
But there are fewer than 3000 cities on the Earth with populations of 100,000 or more. You cannot find anything like a million Hiroshimas to obliterate. Prime military and industrial targets that are far from cities are comparatively rare. Thus, there are vastly more nuclear weapons than are needed for any plausible deterrence of a potential adversary.
Nuclear Winter and the End of the Arms Race: Carl Sagan Interview (1991)
The Film Archives on Sep 3, 2013
Nuclear Winter War- Carl Sagan