In a paper in the journal Science, published on 5 March, researchers from Russia, Sweden and the USA reported their results from 5000 at-sea measurements of dissolved methane in the coastal waters off of Eastern Siberia. They showed that most of the bottom waters and more than half of the surface waters of the East Siberian Arctic Shelf contained supersaturations of methane - a supersaturation represents more methane than expected and indicates a source other than the atmosphere. They determined that the methane entered the ocean waters from below, from the large reserviors of methane and other carbon in the sub-sea permafrost.

In places, they also observed high concentrations of methane in the atmosphere, methane that had first entered the ocean and then escaped to the atmosphere - see the figure below.

Because methane becomes a global greenhouse gas, release of methane from any northern sources, the sub-sea permafrost or the land permafrost, will have global impact. What happens at the poles affects us all! The authors of this study conclude "Leakage of methane through shallow ESAS waters needs to be considered in interactions between the biogeosphere and a warming Arctic climate." Indeed!

For more information, see this USA National Science Foundation announcement. For background information, and for the source of the image used here, see this WWF Report, 'Arctic Climate Feedbacks: Global Implications'.