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hatrack

(59,578 posts)
Fri Apr 14, 2017, 07:55 AM Apr 2017

Observed Permafrost Thaw 20% Faster Than Models; From 17 Million Km2 In 1800s To 15 Million Now

Even in a world at 1 to 1.2 C warmer than 19th Century averages the permafrost is in trouble.

Already, vast thawed lands are starting to release carbon dioxide and methane. Thermokarst lakes bubble with the stuff. And pingos are now starting to erupt as the ice relinquishes the soils of Siberia. Russians, ironically concerned about the safety of an oil and gas infrastructure that helped to precipitate the warming in the first place, are starting to install seismographs to detect these new warming-induced eruptions from the thawed lands. Meanwhile, each new summer brings with it ridiculously warm temperatures, never before seen Arctic thunderstorms, and epic wildfires that rage over these growing piles of peat-like carbon laid down during the course of millions of years of glaciation — but now unlocked in just years and decades by an unnatural thaw.


Back in the late 1800s, permafrost covered about 17 million square kilometers of the Northern Hemisphere. In less than 150 years, that extent has been reduced by 2 million square kilometers due to the warming that has, to date, been produced by fossil fuel burning and related carbon emissions. Even worse, according to the new research, present temperatures alone are enough to, this Century, push permafrost coverage back to 12.5 million square kilometers.

That’s about 1/4 of the world’s permafrost gone due to just 1 to 1.2 degrees Celsius of global warming.

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(A new study shows that 2 C worth of warming nearly cuts preindustrial permafrost extent in half to around 9 million square kilometers. Warming to 6 C above 1880s averages, which will occur so long as fossil fuel burning continues, will wipe out nearly all of the Northern Hemisphere’s permafrost. These thaw rates are about 20 percent more than previously estimated. Image source: An observation-based constraint on permafrost loss as a function of global warming.)

EDIT

https://robertscribbler.com/2017/04/13/the-permafrost-is-thawing-20-percent-faster-than-previously-thought/#comments

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