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Published on Sunday, February 20, 2011 by Inter Press Service
by Stephen Leahy
UXBRIDGE - Thawing permafrost is threatening to overwhelm attempts to keep the planet from getting too hot for human survival.
Without major reductions in the use of fossil fuels, as much as two-thirds of the world's gigantic storehouse of frozen carbon could be released, a new study reported. That would push global temperatures several degrees higher, making large parts of the planet uninhabitable.
Once the Arctic gets warm enough, the carbon and methane emissions from thawing permafrost will kick-start a feedback that will amplify the current warming rate, says Kevin Schaefer, a scientist at the National Snow and Ice Data Center (NSIDC) in Boulder, Colorado. That will likely be irreversible.
And we're less than 20 years from this tipping point. Schaefer prefers to use the term "starting point" for when the 13 million square kilometres of permafrost in Alaska, Canada, Siberia and parts of Europe becomes a major new source of carbon emissions.
"Our model projects a starting point 15 to 20 years from now," Schaefer told IPS.