13 March 2010
As a greenhouse gas, methane is 30 times more potent than carbon dioxide.
According to University of Alaska Arctic researchers Natalia Shakhova and Igor Semiletov, methane gas is venting from the East Siberian Arctic Shelf (ESAS) at a surprisingly high rate. The vents are coming through leaks in permafrost, which forms a cap over methane stored in deeper sediments.
While permafrost is generally viewed as a terrestrial soil, it actually extends offshore beneath a broad area of shallow marine sediments. This area of marine permafrost, about 2 million square kilometers, is the most unstable in the Arctic after several years of warming temperatures.
In the video Shakhova indicates the rate of methane venting at the ESAS equals the methane emitted currently by the rest of the global ocean.