The thawing of permafrost in the Arctic is accelerating the crumbling of coastlines and releasing large amounts of carbon into the atmosphere. This emerges from research by geoscientist Fleur van Crimpen, who mapped the effects of thawing permafrost along Canada’s Beaufort Sea.
Permafrost is soil that remains frozen for at least two years and contains nearly twice as much carbon as is currently present in the atmosphere. As temperatures rise, this frozen ground thaws, making coastlines unstable and literally causing them to collapse. Plant remains and other organic material are washed into the sea, where in the shallow coastal waters this material decomposes quickly, releasing CO₂ — a process that can further amplify global warming.
Van Crimpen discovered that these shallow coastal zones play a key role in determining what happens to the released carbon: does it stay nearby and decompose rapidly, or sink deeper into the ocean where it may be stored for long periods? Since these shallow coastal waters have so far been little studied, her work provides important new insights for climate scientists.
Impact on indigenous communities
But the consequences are not only scientific, measurable in numbers and graphs. The disappearance of frozen coastal land has a major impact on Indigenous communities in the Arctic. In villages such as Tuktoyaktuk in Canada, homes, food storage facilities, and roads are at risk of literally collapsing due to the thawing ground. “What’s happening here directly affects people’s daily lives,” Van Crimpen emphasizes.
The findings help scientists better predict how much additional CO₂ could be released through coastal erosion — crucial information for climate models and policy, which aim to determine how fast the planet will continue to warm and what measures are needed to curb it. In the short term, the research could contribute to improved risk maps for vulnerable coastal regions. In the long term, it offers leads for climate adaptation and the protection of communities living on permafrost — more than 4.9 million people worldwide.
The study makes it clear that thawing permafrost is not a distant concern, but a tangible link in the global climate system — with consequences for both the planet’s climate and the people living at its front lines.
Van Crimpen defends her PhD November 17 at Vrije Universiteit Amsterdam