Enormous sinkholes, the size of a city block with a six-storey building have been discovered on the floor of the Arctic ocean. Marine scientists have also discovered ice-filled hills on the seafloor. The discoveries were made during mapping of Canada's Beaufort Sea. Scientists say the formation is a result of thawing submerged permafrost and retreating glaciers from the last ice age.
Permafrost or ground that is permanently frozen has been thawing in the Arctic, which is warming quicker than any other region on Earth. The thawing of permafrost—which in some cases has remained frozen for hundreds or thousands of years has caused the ground to become unstable.
Scientists observed the changes occur between 2010- 2019, during which four mapping surveys have taken place. This is the first time submerged permafrost has been mapped. It is not yet known how widespread these changes might be elsewhere in the Arctic ocean.
"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," marine geologist Charlie Paull, a senior scientist at Monterey Bay Aquarium Research Institute told CNN.
Thawing of the permafrost has caused changes like the formation or disappearance of lakes, craters formed by blowouts of methane gas contained in the permafrost, which has in turn affected infrastructures like roads and pipelines.