Permafrost melt “is climate threat”

The amount of carbon locked away in the frozen soils of the earth’s far northern hemisphere is double previous estimates and rapid melting could accelerate global warming, Reuters reported, citing a new Australian study. A four-year examination of the latest research on permafrost, data from new drilling projects and the release of previously unpublished Russian data led to a rethink of carbon levels.


Permafrost — deep layers of frozen soil near the surface – lies in large areas of northern Russia, Canada, the Nordic countries and the American state of Alaska. In some places, climate change already has triggered its rapid melting, releasing the greenhouse gases carbon dioxide and methane. More of the gases is expected to be released, driving up temperatures, as the world gets warmer.


“Massive amounts of carbon stored in frozen soils at high latitudes are increasingly vulnerable to exposure to the atmosphere,” according to Pep Canadell of the Global Carbon Project at Australia’s Commonwealth Scientific and Industrial Research Organisation. “The research shows that the amount of carbon stored in soils surrounding the North Pole has been hugely underestimated.” The study is published in the journal Global Biogeochemical Cycles.


Canadell said: “Projections show that almost all near-surface permafrost will disappear by the end of this century, exposing large carbon stores to decomposition and release of greenhouse gases.” Permafrost at the southern limit of northern China has all but disappeared over the past 20 years, he told Reuters. On a recent trip to the area, Canadell said, local people told him that the permafrost, once 20 centimetres below the surface, now was several metres down.


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