“A nuclear war between any nuclear states, using much less than one percent of the current nuclear arsenal, would produce climate change unprecedented in human history. A small nuclear war could reduce food production by 10 to 40 percent for a decade, with massive increases in ultraviolet radiation (which causes deadly skin cancers).”

— Alan Robock, professor of climate science in the Department of Environmental Sciences at Rutgers University
From the article: Professor: Nuclear war might cause crop failures, famine; ways to prevent oakridger.com