ARCTIC METHANE EMISSIONS

Arctic methane emissions ‘greater’ than previous estimates1 515 Shares Facebook 450 Reddit 42 Google+ 1 TwitterEmailPrintFriendly.comSumoMe Published on 06/01/2016, 12:11pm Methane, a key greenhouse gas, is released from Arctic soils not only in the short summer period but also during the bitterly cold winters The Arctic Tundra is found across Alaska, Canada and Siberia, enjoying long fierce winters and shorter cool summers (Pic: Pixabay) The Arctic Tundra is found across Alaska, Canada and Siberia, enjoying long fierce winters and shorter cool summers (Pic: Pixabay) By Alex Kirby The quantity of methane leaking from the frozen soil during the long Arctic winters is probably much greater than climate models estimate, scientists have found. They say at least half of annual methane emissions occur in the cold months from September to May, and that drier, upland tundra can emit more methane than wetlands. The multinational team, led by San Diego State University (SDSU) in the US and including colleagues from the National Oceanic and Atmospheric Administration, and the University of Sheffield and the Open University in the UK, have published their conclusion, which challenges critical assumptions in current global climate models, in the Proceedings of the National Academy of Sciences. Methane, a potent greenhouse gas, is about 25 times more powerful per molecule than carbon dioxide over a century, but more than 84 times over 20 years. The methane in the Arctic tundra comes primarily from organic matter trapped in soil which thaws seasonally and is decomposed by microbes. It seeps naturally from the soil over the course of the year, but climate change can warm