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Glacial, Icecap and Parmafrost Melting XX: Fairbanks, Alaska, 2006

Glacial, Icecap and Parmafrost Melting XX: Fairbanks, Alaska, 2006

Fairbanks: photographed September 2006.

Permafrost is defined by the National Snow and Ice Data Center as a “layer of soil or rock, at some depth beneath the surface, in which the temperature has been continuously below 0 °C for at least some years. It exists where summer heating fails to reach the base of the layer of frozen ground.”  The photographs here are of trees that have fallen as the land beneath them buckles with the melting of long frozen soil. Such scenes are referred to as “Drunken Forests.”

Scientists have observed widespread melting of permafrost, which has seemed to accelerate in recent years.  This is significant to local ecosystems, particularly in Alaska and Siberia, but far more significant is the threat that such melting will lead to the release of massive amounts of carbon dioxide and methane that are currently stored in the soils that have been frozen for thousands of years.  This would create a feedback loop where more melting would cause more thawing, which would in turn cause more melting.  Such feedback loops threaten to abruptly alter the climate.  (See also entries for Antarctica, Belize Barrier Reef, Monteverde Cloud Forest).

A survey conducted at the end of 2011 and published in the peer-reviewed journal Nature found that scientists believe the problem is potentially much worse than previously thought.  It is unusual that such a technical survey would capture national media attention, but this one did.  This is because of the importance these stronger-than-predicted melting trends have for the future stability of the climate.  For example, the New York Times reported that: “A recent estimate suggests that the perennially frozen ground known as permafrost, which underlies nearly a quarter of the Northern Hemisphere, contains twice as much carbon as the entire atmosphere.”  As one scientist quoted in the New York Times said: “To me, it’s a spine-tingling feeling, if it’s really old carbon that hasn’t been in the air for a long time, and now it’s entering the air,” Dr. Schuur said.  “That’s the fingerprint of a major disruption, and we aren’t going to be able to turn it off someday.”