RedOrbit, By Lawrence LeBlond, February 12
Researchers studying Arctic thermokarst failures in Alaska were alarmed to find climate-warming carbon dioxide gas may be releasing into the atmosphere at an unprecedented rate. This release is being caused by melting of the Arctic permafrost, which has kept ancient carbon locked away for millennia; only to be exposed as more warmth and sunlight erodes the long-frozen soils, causing collapse and release of carbon.
George Kling, an ecologist and aquatic biogeochemist at the University of Michigan, said these areas where the permafrost is melting are causing land surfaces to erode and collapse, exposing long-buried soils to sunlight. This sunlight increases bacterial conversion of the exposed soil carbon into CO2 by at least 40 percent compared to carbon that remains in the dark.
The study was led by Rose Cory, of the University of North Carolina, and published online (Feb 11) in the Proceedings of the National Academy of Sciences (PNAS).
“What we can say now is that regardless of how fast the thawing of the Arctic permafrost occurs, the conversion of this soil carbon to carbon dioxide and its release into the atmosphere will be faster than we previously thought,” Kling said in a statement. “That means permafrost carbon is potentially a huge factor that will help determine how fast the Earth warms.”