The Arctic Ocean could be a significant contributor of methane, a powerful greenhouse gas, scientists reported on Sunday. Researchers carried out five flights in 2009 and 2010 to measure atmospheric methane in latitudes as high as 82 degrees north. They found concentrations of the gas close to the ocean surface, especially in areas where sea ice had cracked or broken up. The study, published in the journal Nature Geoscience, wonders if this is a disturbing new mechanism that could accelerate global warming. "We suggest that the surface waters of the Arctic Ocean represent a potentially important source of methane, which...
