Melting permafrost causes rapid changes to the Arctic seafloor

The thawing of permafrost creates unstable terrain that negatively affects important infrastructure in the Arctic, such as roads or railways. Now, a study confirms that it also influences, with drastic changes, the seabed.

This melting of submerged permafrost has formed deep sinkholes in some underwater areas, some larger than six-story buildings, and has raised ice-filled hills called pingos, concludes research published in the journal PNAS.

Its leaders are scientists from the MBARI (Monterey Bay Aquarium Research Institute)who state that this study is the first to document how thawing permafrost submerged underwater at the edge of the ocean Arctic It is affecting the seabed.

A statement from the aforementioned center recalls that numerous studies have shown that the thawing of permafrost negatively affects important infrastructure in the Arctic and its repair is expensive.

Now, using advanced underwater mapping technology, researchers at the MBARI and his collaborators revealed that drastic changes are also taking place on the seafloor.

Charles K Paull and his team conducted four surveys of the seabed in Beaufortin the north of Canadabetween 2010 and 2019.

Canada’s Beaufort Sea, a remote area of ​​the Arctic, has only recently been accessible to scientists as climate change drives sea ice retreat.

At depths between 120 and 150 meters, near the edge of the submerged permafrost, the authors observed the formation of depressions with steep sides up to 28 meters deep.

The authors attribute the depressions to the rise of groundwater produced by melting ice.

“We know that big changes are taking place in the Arctic landscape, but this is the first time we have been able to use technology to see that changes are also taking place in the sea.”Paul sums it up.

This research -he adds- reveals how the melting of underwater permafrost can be detected and, once the baselines are established, tracked.

While the degradation of terrestrial permafrost in the Arctic is attributed, in part, to increases in average annual temperature due to human-caused climate change, permafrost-associated seafloor changes stem from much older climate changes and slow related to our exit from the last ice age, the study notes.

Rapid morphological changes associated with active thawing of subsea permafrost may be an important process in “the sculpture” of the seafloor in other settings, the authors conclude.

Since 2003, the MBARI has been part of an international collaboration to study the Beaufort seafloor with the Geological Survey of Canada, the Canadian Department of Fisheries and Oceans and, since 2013, with the Korea Polar Research Institute.