Investigating methane

Bubbles of warming, beneath the ice - Los Angeles Times

The potential for trouble from methane and other carbon being released from thawing Arctic regions is given a bit of an overview in this article. Some disturbing thoughts:

The upper 3 meters -- about 10 feet -- of permafrost stores 1.9 trillion tons of carbon, more than double the amount in the atmosphere today, according to a recent study in the journal Bioscience.

"We are seeing thawing down to 5 meters," says geophysicist Vladimir Romanovsky of the University of Alaska. "A third to a half of permafrost is already within a degree to a degree and a half [Celsius] of thawing."

If only 1% of permafrost carbon were to be released each year, that could double the globe's annual carbon emissions, Romanovsky notes. "We are at a tipping point for positive feedback," he warns, referring to a process in which warming spurs emissions, which in turn generate more heat, in an uncontrollable cycle.