To see what climate effects such a regional nuclear conflict might have, scientists from NASA and other institutions modeled a war involving a hundred Hiroshima-level bombs, each packing the equivalent of 15,000 tons of TNT—just 0.03 percent of the world's current nuclear arsenal.
The researchers predicted the resulting fires would kick up roughly five million metric tons of black carbon into the upper part of the troposphere, the lowest layer of the Earth's atmosphere.
In NASA climate models, this carbon then absorbed solar heat and, like a hot-air balloon, quickly lofted even higher, where the soot would take much longer to clear from the sky.
The global cooling caused by these high carbon clouds wouldn't be as catastrophic as a superpower-versus-superpower nuclear winter, but "the effects would still be regarded as leading to unprecedented climate change," research physical scientist Luke Oman said during a press briefing Friday at a meeting of the American Association for the Advancement of Science in Washington, D.C.
Earth is currently in a long-term warming trend. After a regional nuclear war, though, average global temperatures would drop by 2.25 degrees F (1.25 degrees C) for two to three years afterward, the models suggest.
At the extreme, the tropics, Europe, Asia, and Alaska would cool by 5.4 to 7.2 degrees F (3 to 4 degrees C), according to the models. Parts of the Arctic and Antarctic would actually warm a bit, due to shifted wind and ocean-circulation patterns, the researchers said.
After ten years, average global temperatures would still be 0.9 degree F (0.5 degree C) lower than before the nuclear war, the models predict.
For a time Earth would likely be a colder, hungrier planet.
"Our results suggest that agriculture could be severely impacted, especially in areas that are susceptible to late-spring and early-fall frosts," said Oman, of NASA's Goddard Space Flight Center in Greenbelt, Maryland.
"Examples similar to the crop failures and famines experienced following the Mount Tambora eruption in 1815 could be widespread and last several years," he added. That Indonesian volcano ushered in "the year without summer," a time of famines and unrest.
All these changes would also alter circulation patterns in the tropical atmosphere, reducing precipitation by 10 percent globally for one to four years, the scientists said. Even after seven years, global average precipitation would be 5 percent lower than it was before the conflict, according to the model.
In addition, researcher Michael Mills, of the National Center for Atmospheric Research in Colorado, found large decreases in the protective ozone layer, leading to much more ultraviolet radiation reaching Earth's surface and harming the environment and people.
"The main message from our work," NASA's Oman said, "would be that even a regional nuclear conflict would have global consequences."
I can see the Korean peninsula becoming the hub of global climate change. Come on, Korea! Let's nuclear!
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Anyone who was paying attention in the 80's and 90's already knows about nuclear winter. However, I am quite distrustful of the models, since 1) I have done modeling for a living in the past and know its weaknesses, 2) the weather models used for climate prediction have so far been wrong, 3) anything in National Geographic on climate is suspect for promoting an agenda. (I learned that the hard way after being a member for 53 years)
ReplyDeleteThe fact that it presupposes global warming raises a flag in my book.
While that sounds like a real nifty idea, I'd rather if they found another solution for global warming.
ReplyDeleteI note, somewhat ironically, that last week The US revealed there were so-called suitcase Nukes or tactical Nuclear Weapons, as well as warheads hanging from the wings of fighter jets right up until the end of the 90's in Korea.
ReplyDeleteAnd then this week several Korean parliamentarians have called for a return of nukes to The South.
-Face Palm-
As a Kiwi brought up in a tradition of striving for a nuclear free kinda world, I would seriously consider leaving Korea is there were nuclear weapons here...