Mapping Reveals Rapid Changes to the Arctic Seafloor As Ancient Submerged Permafrost Thaws

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Across the Arctic, numerous peer-reviewed studies show that thawing permafrost creates unstable land which negatively impacts important infrastructure and impacts Indigenous communities.

Across the Arctic, numerous peer-reviewed studies show that thawing permafrost creates unstable land which negatively impacts important infrastructure and impacts Indigenous communities. Now, a new study from MBARI researchers and their collaborators published in the Proceedings of the National Academy of Sciences finds dramatic changes offshore and is the first to document how the thawing of permafrost submerged underwater at the edge of the Arctic Ocean is affecting the seafloor.

About one quarter of the land in the Northern Hemisphere is permafrost or frozen ground. At the end of the last ice age (12,000 years ago) melting glaciers and sea level rise submerged large swaths of permafrost. Until just recently, this submerged permafrost had been largely inaccessible to researchers. But now, thanks to technological advancements, including MBARI’s autonomous mapping robots, scientists are able to conduct detailed surveys and assess changes in the seafloor.

High-resolution bathymetric surveys in the Canadian Beaufort Sea have revealed changes in the seabed from 2010 to 2019. Using autonomous mapping robots, scientists documented multiple large sinkhole-like depressions—the largest the size of an entire city block of six-story buildings—had developed in less than a decade.

“We know that big changes are happening across the Arctic landscape, but this is the first time we’ve been able to deploy technology to see that changes are happening offshore too,” said Charlie Paull, a geologist at MBARI who led the study with Scott Dallimore from the Geological Survey of Canada, Natural Resources Canada, and an international team of researchers. “While the underwater sinkholes we have discovered are the result of longer-term, glacial-interglacial climate cycles, we know the Arctic is warming faster than any region on Earth. As climate change continues to reshape the Arctic, it’s critical that we also understand changes in the submerged permafrost offshore.”

Read more at: Monterey Bay Aquarium Research Institute

MBARI’s autonomous underwater vehicle (AUV) is recovered after completing a successful seafloor mapping mission in the Arctic Ocean. The remotely operated vehicle (ROV, foreground) is used to conduct visual surveys of the newly mapped seafloor. (Photo Credit: Charlie Paull © 2016 MBARI)