VLADIVOSTOK, 2 September 2 (RIA Novosti) Russian, U.S. scientists set to study methane release in Arctic : "We assume that the leakage of methane results from the degradation of underwater permafrost... A massive release of such a powerful greenhouse gas may accelerate global warming," Russian, U.S. scientists set to study methane release in Arctic The 45-day expedition will focus on the sea shelf of the Laptev Sea, the East Siberian Sea and the Russian part of the Chukotsk Sea, where 90% of underwater permafrost is located. © RIA Novosti. Valery Yarmolenko 01:32 02/09/2011 VLADIVOSTOK, September 2 (RIA Novosti) Related News Denmark, Greenland and Faroe Islands agree on Arctic strategy Geographers to discuss Arctic Sea Route at second Arctic Forum Russia's Arctic force may include paratroopers - general Russian research vessel begins Arctic shelf research Multimedia Arctic breakthrough: Expedition of sailing ship Sedov sets new ...