I first began to become aware of the phenomenon of melting permafrost in the early 1980s when I read about tombstones of Alaska's early settlers tipping over because permafrost was melting. And now, a long time Alaskan resident that I met recently shared how winter's lowest winter temperatures in the Arctic are about 20 degrees above normal. Then I read about how it is the higher winter temperatures that are having the greatest influence in permafrost melting.
Search: Siberian Alaskan Arctic Permafrost
https://m.phys.org/news/2017-06-defrosting-world-freezerthawing-permafrost.html
https://www.nytimes.com/interactive/2017/08/23/climate/alaska-permafrost-thawing.html
https://en.m.wikipedia.org/wiki/Arctic_methane_emissions
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