as far back as 2011, NOAA and the National Snow and Ice Data Center predicted that thawing permafrost would flip the whole region from being what is called a carbon sink, which absorbs atmospheric carbon, to a carbon source, which releases carbon, as quickly as the 2020s. By 2100, the same study said, the Arctic could release a hundred billion tons of carbon. That is the equivalent of half of all the carbon produced by humanity since industrialization began.
