subsea permafrost

Subsea permafrost refers to perennially frozen ground found beneath the Arctic Ocean's continental shelves. It originated during the last glacial epoch, when much of the Arctic seabed was exposed to cold climates, causing permafrost to form to depths of over 700 meters. As sea levels rose, this frozen ground became submerged.123

The saltwater environment has caused this subsea permafrost to degrade and melt, reducing its strength. Subsea permafrost is sensitive to warming from geothermal heat and human activities. Thawing subsea permafrost can release methane, a potent greenhouse gas, contributing to a positive feedback loop that accelerates warming and further thawing. This process can also mobilize pollutants from the soil, negatively impacting aquatic ecosystems. Understanding subsea permafrost is crucial for offshore resource exploration and infrastructure development.32