Ancient Permafrost and a Future, Warmer Arctic
Duane G. Froese,1*
John A. Westgate,2
Alberto V. Reyes,1
Randolph J. Enkin,3
Shari J. Preece2
Climate models predict extensive and severe degradation of permafrost
in response to global warming, with a potential for release
of large volumes of stored carbon. However, the accuracy of
these models is difficult to evaluate because little is known
of the history of permafrost and its response to past warm intervals
of climate. We report the presence of relict ground ice in subarctic
Canada that is greater than 700,000 years old, with the implication
that ground ice in this area has survived past interglaciations
that were warmer and of longer duration than the present interglaciation.
2 Department of Geology, University of Toronto, Toronto, ON M5S 3B1, Canada.
3 Geological Survey of Canada–Pacific, Sidney, BC V8L 4B2, Canada.
* To whom correspondence should be addressed. E-mail: duane.froese{at}ualberta.ca
