Huge amounts of carbon are contained in sediments, soils and vegetation in the Arctic. Rising temperatures in the Arctic threaten to cause much of this carbon to be released to the atmosphere.
On May 23, 2015, temperatures in Alaska were as high as 91°F (32.78°C), as illustrated by the image below.
[ image credit: US National Weather Service Alaska ] |
A bank of permafrost thaws near the Kolyma River in Siberia. Credit: University of Georgia |
Carbon contained in soils will thus become increasingly exposed under the combined impact of rising temperatures and the associated growing amounts of meltwater. The meltwater can additionally cause erosion further downstream, thus making carbon at many locations become more prone to be consumed by microbes and released into the atmosphere in the form of carbon dioxide and methane.
A recent study found that, at a location where the Kolyma river in Siberia carved into the permafrost and exposed the carbon, microbes converted 60% of the carbon into carbon dioxide in two weeks time.
Gary Houser, who recently launched the movie Sleeping Giant in the Arctic, elaborates on the threat of emissions from thawing permafrost:
This immense release would likely feed on itself, raising temperatures that continue melting more and more permafrost in a vicious, frightening, and unstoppable cycle. A tipping point could well be crossed, at which time human intervention is no longer possible. Temperatures across the planet could soar, setting in motion catastrophic levels of drought and food shortage. All life support systems on earth and life forms themselves could be placed under severe stress.
The colossal scale of the danger - and the observation of those factors lining up that could trigger it - demand that humanity exercise the precautionary principle. All political decision-making related to carbon emissions must be based on the understanding that a catastrophic consequence is looming, and the window of time for prevention quickly diminishing.
SLEEPING GIANT IN THE ARCTIC:
Can Thawing Permafrost Cause Runaway Global Heating?
by Gary Houser
Sources:
US National Weather Service Alaska
University of Georgia
Sleeping Giant in the Arctic
Sleeping Giant in the Arctic http://arctic-news.blogspot.com/2015/05/sleeping-giant-in-the-arctic.html
Posted by Sam Carana on Monday, May 25, 2015
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