Arctic Ocean is an emission source of methane, study finds – big picture

Researchers have known for years that large amounts of methane are frozen in Arctic tundra soils and in marine sediments (including gas hydrates). But now a multi-institutional study led by Eric Kort of Nasa's Jet Propulsion Laboratory has uncovered a surprising and potentially important new source of methane: the Arctic itself. The photograph shows leads and cracks in the ice cover of the Arctic Ocean north of Alaska, 19 August 2011
Illustration: Courtesy Eric Kort/Jet Propulsion Laboratory