Guardian Unlimited
A vast expanse of western Sibera is undergoing an unprecedented thaw that could dramatically increase the rate of global warming, climate scientists warn today. Researchers who have recently returned from the region found that an area of permafrost spanning a million square kilometres - the size of France and Germany combined - has started to melt for the first time since it formed 11,000 years ago at the end of the last ice age. The area, which covers the entire sub-Arctic region of western Siberia, is the world's largest frozen peat bog and scientists fear that as it thaws, it will release billions of tonnes of methane, a greenhouse gas 20 times more potent than carbon dioxide, into the atmosphere.
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The researchers found that what was until recently a barren expanse of frozen peat is turning into a broken landscape of mud and lakes, some more than a kilometre across. Dr Kirpotin told the magazine the situation was an "ecological landslide that is probably irreversible and is undoubtedly connected to climatic warming". He added that the thaw had probably begun in the past three or four years.
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Western Siberia is heating up faster than anywhere else in the world, having experienced a rise of some 3C in the past 40 years. Scientists are particularly concerned about the permafrost, because as it thaws, it reveals bare ground which warms up more quickly than ice and snow, and so accelerates the rate at which the permafrost thaws.
Siberia's peat bogs have been producing methane since they formed at the end of the last ice age, but most of the gas had been trapped in the permafrost. According to Larry Smith, a hydrologist at the University of California, Los Angeles, the west Siberian peat bog could hold some 70bn tonnes of methane, a quarter of all of the methane stored in the ground around the world. The permafrost is likely to take many decades at least to thaw, so the methane locked within it will not be released into the atmosphere in one burst, said Stephen Sitch, a climate scientist at the Met Office's Hadley Centre in Exeter. But calculations by Dr Sitch and his colleagues show that even if methane seeped from the permafrost over the next 100 years, it would add around 700m tonnes of carbon into the atmosphere each year, roughly the same amount that is released annually from the world's wetlands and agriculture. It would effectively double atmospheric levels of the gas, leading to a 10% to 25% increase in global warming, he said.
Perhaps too little too late, Republican Senators are growing concerned about Global Warming.
Los Angeles Times
Fresh from visits to the Yukon in Canada and Alaska's northernmost city, four U.S. senators said Wednesday that signs of rising temperatures on Earth were obvious, and they called on Congress to act. "If you can go to the Native people and listen to their stories and walk away with any doubt that something's going on, I just think you're not listening," Sen. Lindsey Graham (R-S.C.) said. He was accompanied on the trip by Sens. John McCain (R-Ariz.), Susan Collins (R-Maine) and Hillary Rodham Clinton (D-N.Y.).
The senators said in Anchorage that Inupiat Eskimo residents in Barrow, Alaska's northernmost city, had found their ancestral land and traditional lifestyle disrupted by disappearing sea ice, thawing permafrost, increased coastal erosion and changes to wildlife habitat. Heat-stimulated beetle infestation has killed vast amounts of the spruce forest in the Yukon, the senators said.
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