Consequences of a large nuclear war
Following a large U.S.-Russian nuclear war, enormous fires created by nuclear explosions in cities and industrial areas cause 150 million tons of smoke to be lofted high into the stratosphere. The smoke is quickly spread around the world and forms a dense smoke layer around both Hemispheres; the smoke will remain in the stratosphere for many years and act to block sunlight from reaching the surface of the Earth. New studies predict this level of stratospheric smoke deposition will still be possible even after planned reductions in U.S.-Russian nuclear arsenals are completed under the SORT Treaty in 2012.
Summary of consequences: U.S.-Russian war producing 150 million tons of smoke