Quirks & Quarks

Arctic permafrost is thawing faster than expected

Ice wedges that penetrate deep into permafrost are degrading and accelerating the melt of Arctic permafrost

Degradation of ice wedges is opening up permafrost to faster melting

Subsurface ice wedges often form polygon shapes in the Arctic landscape (Jessica Cherry)

Scientists estimate that the amount of carbon dioxide locked up in the Arctic permafrost is twice the amount found in the atmosphere of the entire planet. Because much of the permafrost was thought to be protected from climate change, scientists believed that CO2 would not be released.

But a new study by Dr. Anna Liljedahl, a Research Assistant Professor from the Water and Environment Research Center at the University of Alaska, has found that in some areas of the Arctic, the permafrost is thawing faster than expected. Winter cracks open the ground, then fill in with summer meltwater, forming ice wedges 10 to 15 metres deep in the permafrost. Rising temperatures in recent years have resulted in a degradation of the ice wedges, which results in a thawing of the permafrost.

Scientists are uncertain at this point about how much carbon the permafrost can emit through this process, but are sure it will contribute to an already warming planet.

Related Links

Paper in Nature Geoscience
- University Of Alaska, Fairbanks release
- Los Alamos National Laboratory release
- Washington Post story