Even a relatively small regional nuclear war could trigger global cooling, damage the ozone layer and cause droughts for more than a decade, researchers say.
These findings should further spur the elimination of the more than 17,000 nuclear weapons that exist today, scientists added.
During the Cold War, a nuclear exchange between superpowers was feared for years. One potential consequence of such a global nuclear war was "nuclear winter," wherein nuclear explosions sparked huge fires whose smoke, dust and ash blotted out the sun, resulting in a "twilight at noon" for weeks. Much of humanity might eventually die from the resulting crop failures and starvation. [Doomsday: 9 Real Ways the Earth Could End]
Today, with the United States the only standing superpower, nuclear winter might seem a distant threat. Still, nuclear war remains a very real threat; for instance, between developing-world nuclear powers such as India and Pakistan.
To see what effects such a regional nuclear conflict might have on climate, scientists modeled a war between India and Pakistan involving 100 Hiroshima-level bombs, each packing the equivalent of 15,000 tons of TNT — just a small fraction of the world's current nuclear arsenal. They simulated interactions within and between the atmosphere, ocean, land and sea ice components of the Earth's climate system.
Scientists found the effects of such a war could be catastrophic.
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