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Updated: Jun 30, 2026
09:06
Removal of Exogenous Materials from the Outer Portion of Frozen Cores to Investigate the Ancient Biological Communities Harbored Inside
Published on: July 3, 2016
Ancient permafrost and a future, warmer Arctic.
Duane G Froese1, John A Westgate, Alberto V Reyes
1Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, AB T5M 0M3, Canada. duane.froese@ualberta.ca
Science (New York, N.Y.)
|September 20, 2008
Summary
Ancient permafrost in Canada, over 700,000 years old, has survived past warm periods. This discovery challenges climate models predicting widespread permafrost thaw due to global warming.
Area of Science:
- Earth Science
- Paleoclimatology
- Climate Science
Background:
- Climate models forecast significant permafrost degradation under global warming, potentially releasing substantial stored carbon.
- Evaluating these models is challenging due to limited understanding of permafrost's historical behavior during past warm climates.
Purpose of the Study:
- To investigate the long-term stability of permafrost and its resilience to past interglacial warming events.
- To provide empirical data for refining climate models' predictions of permafrost response to warming.
Main Methods:
- Geological surveys and analysis of relict ground ice deposits in subarctic Canada.
Main Results:
- Discovery of relict ground ice exceeding 700,000 years in age.
- Evidence suggests this ancient ground ice persisted through multiple past interglaciations.
Conclusions:
- Permafrost in this region exhibits greater stability than predicted by current climate models.
- Past warmer interglacials, longer than the present, did not cause complete thaw of this ancient ground ice.
- Findings necessitate a re-evaluation of permafrost carbon feedback mechanisms in climate change projections.
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