A vast outcrop of the Arctic Siberian coast, frozen for tens of thousands of years, is releasing huge carbon deposits as rising temperatures thaw parts of its coastline, a study in the journal Nature warns, reports Agence France Presse in the Australian News. The ice age carbon, a potential source of Earth-warming CO2, has lain frozen along the 7000km northeast Siberian coast. But atmospheric warming and coastal erosion are gnawing at the icy seal, releasing about 40 million tonnes of carbon a year – 10 times more than previously thought, the study found, and equal to the annual emissions of 10 million cars. About two-thirds of the carbon escapes into the atmosphere as carbon dioxide, while the rest becomes trapped in higher layers of ocean sediment. Roughly half of the vast carbon pool stored in soil globally is held in permafrost in the Arctic, a region that is experiencing twice the global average of climate warming, said the study. Released carbon enters a vicious feedback cycle, enhancing global warming further that, in turn, releases yet more Siberian stored carbon.
Siberian thaw unlocks ice-age carbon vault. A vast outcrop of the Arctic Siberian coast that had been frozen for tens of thousands of years is releasing huge carbon deposits as rising temperatures thaw parts of its coastline, a study warned yesterday. Agence France-Presse