Climate Change - Permafrost and greenhouse gases

Arctic permafrost – ground that has been frozen for many thousands of years – is now thawing because of global climate change.
“The release of greenhouse gases resulting from thawing Arctic permafrost could have catastrophic global consequences,” said Dr. Max Holmes, a Senior Scientist at the Woods Hole Research Center (WHRC).


Schematic diagram of greenhouse gases and permafrost.  

Thawing permafrost releases greenhouse gases (carbon dioxide and methane) into the atmosphere, which accelerates climate change, which in turn causes more thawing of the permafrost. 

Some scientists fear that this potentially unstoppable and self-reinforcing cycle could produce a dangerous "tipping point".

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