Researchers gathering data in a Siberian cave. Credit: University of Oxford

https://scitechdaily.com/discovery-regarding-arctic-sea-ice-and-permafrost-has-significant-implications-for-the-future/

Sea-Ice-Free Arctic Makes Permafrost Vulnerable to Thawing

Permafrost is ground that remains frozen throughout the year; it covers nearly a quarter of Northern Hemisphere land. The frozen state of permafrost enables it to store large amounts of carbon; about twice as much as in the atmosphere. The rate and extent of future thawing of permafrost, and consequent release of its carbon, is hard to predict from modern observations alone.

However, a crucial past relationship between summer sea ice in the Arctic and permafrost, discovered in this study, is now understood, with significant implications for the future.

Professor Gideon Henderson, an author of the study based at the Department of Earth Sciences, University of Oxford, said: ‘We were surprised to find…