A team of scientists, led by a young researcher at the University of Alaska Fairbanks, has had its work published in the most recent issue of the magazine Science, slated to hit newsstands today. UAF researcher Katey Walter, 31, was lead author of the report, which discusses the role of methane gases bubbling from Arctic lakes had in warming the climate more than 10,000 years ago and suggests that similar processes are in the works again, potentially leading to drastic climate warming in coming years.
Ice cores from Greenland and Antarctica have shown that during the early Holocene Period — about 14,000 to 11,500 years ago — the levels of methane in the atmosphere rose significantly. Walter’s research suggests that methane bubbling from the bottom of thermokarst lakes, which are formed when permafrost thaws rapidly, could have been responsible for up to 87 percent of that methane spike.
“Methane is of great concern because of how very potent it is as a greenhouse gas,” Walter said. “Methane is a stronger greenhouse gas. Methane is about 23 times stronger than carbon dioxide.” Walter’s research focused on areas of Siberia and Alaska that, during the last ice age, were dry grasslands atop ice-rich permafrost. As the climate warmed, Walter said, that permafrost thawed, forming thermokarst lakes. “Lakes really flared up on this icy permafrost landscape, emitting huge amounts of methane,” she said.
As the permafrost around and under the lakes thaws, the organic material in it — dead plants and animals — can enter the lake bottom and become food for the bacteria that produce methane. “The more permafrost that thaws, the more food microbes have and the more methane that enters the atmosphere,” Walter said.
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