Thursday, March 4, 2010

Fears of Undersea Methane Leaks Already Coming True


Though immense amounts of carbon are known to be trapped in the peatlands of Siberia, a larger, often unrecognized carbon reservoir lies hidden just north of that frigid region, says Natalia Shakhova, a biogeochemist at the University of Alaska in Fairbanks.

The East Siberian Arctic Shelf — a 2.1-million-square-kilometer patch of Arctic seafloor that was exposed during the most recent ice age, when sea levels were lower — is three times larger than all of today’s land-based Siberian wetlands. When the region was above sea level, tundra vegetation pulled carbon dioxide from the air as plants grew. That organic material, much of which didn’t decompose in the frigid Arctic, accumulated in the soil and is the source of modern methane.
Now, field studies by Shakhova and her colleagues, reported in the March 4 Science, suggest that the submarine reservoir of carbon has begun to leak. More >>>