Giant craters in Canada's melting permafrost impacting climate change: researchers

Researchers are investigating large craters of melting permafrost in northern Canada, which they say areboth a consequence of climate changeand a contributing factor.

Scientists say warming temperatures are melting a previously frozen layer under the surface in Fort McPherson, N.W.T. Frozen organisms in that surface are now being exposed to the air, producingcarbon dioxide and contributingto the greenhouse effect.

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"We know there is twice as much carbon locked up in permafrost as there is carbondioxidein the atmosphere," saysSuzanne Tank, a researcher and assistant professor at theUniversity of Alberta.

"So certainly there is the potential there for this carbon, if it's released as carbondioxide,to have a really huge effect on greenhouse gasses and climate warming."

Scientists are looking to collect samples from the craters to gain more information about the problem, which they call a "sleeping giant."

"There is this uncertainty associated with what this sleeping giant is going to look like," says Tank.