Methane bubbles
Trapped under the frozen layer of Big Trail Lake near Fairbanks, Alaska
Millions thermokarst lakes are formed in the arctic due to permafrost thawing. This permafrost, frozen and organic rich soil, covers about 25% of the northern hemisphere land mass and holds twice as much carbon as the atmosphere does, about 1,600 billion tonnes. Upon thawing, the organic rich content becomes available to decomposition by microorganisms that lead to the removal of oxygen and the formation of methane by methanogenesis. Methane is a greenhouse gas, with 30 times fold potency compared to carbon dioxide, and the methane release from thermokarst lakes has positive feedback to global warming.
Prof. Orit Sivan research group participates in the biogeochemical research of methane formation and consumption in Alaskan thermokarst lakes and other sites in Israel and around the world.
Photograph by Nicholas Hasson, November 2018
See recent publication by Pellerin et al. 2022: Methane production controls in a young thermokarst lake formed by abrupt permafrost thaw.
