The Climate Will Now Change Faster

Exclusive: Some Arctic Ground No Longer Freezing—Even in Winter; New data from two Arctic sites suggest some surface layers are no longer freezing. If that continues, greenhouse gases from permafrost could accelerate climate change.

Craig Welch, August 20. 2018 (National Geographic)

“…Every winter across the Arctic, the top few inches or feet of soil and rich plant matter freezes up before thawing again in summer. Beneath this active layer of ground extending hundreds of feet deeper sits continuously frozen earth called permafrost, which, in places, has stayed frozen for millennia…[But this past winter, for] the first time in memory, ground that insulates deep Arctic permafrost simply did not freeze…[The limited data suggests the global warming-caused permafrost thaw is beginning] decades sooner than many people expect…releasing trapped greenhouse gases that could accelerate human-caused climate change…Trapped in this frozen soil and vegetation is more than twice the carbon found in the atmosphere…

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…As fossil-fuel burning warms the Earth, this ground is thawing, allowing microbes to consume buried organic matter and release carbon dioxide and shorter-lived methane, which is 25 times as potent a greenhouse gas as CO2…[Signs at multiple sites throughout the Arctic] are emerging that the annual freeze-up can quickly change…Arctic weather is famously variable. A few years of heavy snow in some regions could give way quickly to a long stretch of dry cold years…And even scientists uncomfortable with the limited data say the possibility that something so fundamental could change so quickly gives them pause…Most models suggest just 10 to 20 percent [of the permafrost carbon] would escape even at high human emissions scenarios…But more than a dozen Arctic climate scientists contacted by National Geographic agree that this year's active-layer data highlights the limitations of global climate models…” click here for more

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