Melting Arctic permafrost drastically altering coastlines
Today’s Image of the Day comes from the Arctic, where the thawing and erosion of permafrost is changing the landscape of Arctic coasts. Permafrost is any rock or soil that has been frozen for at least two years. As temperatures in the Arctic continue to warm, the permafrost thaws and melts, moving sediment through shallow water areas and causing significant erosion along the shoreline. Pollutants from land that had been previously frozen into the permafrost are then released into marine ecosystems.
In a paper published in the journal Nature Climate Change, a team of scientists from the Alfred Wegener Institute, Helmholtz Centre For Polar And Marine Research led by Dr. Michael Fritz urge the scientific community to focus more on the never-before-seen consequences of permafrost coastal erosion.
According to Fritz, “Herschel Island loses up to 22 metres of coast each year. The thawed permafrost slides down into the sea in the form of mud slides and blurs the surrounding shallow water areas so much that the brownish-grey sediment plumes reach many kilometres into the sea.
“The processes in the arctic coastal zone play an outstanding role for four reasons. Firstly, the thawed organic material is decomposed by microorganisms, producing greenhouse gases. Secondly, released nutrients stimulate the growth of algae, which can lead to the formation of low-oxygen zones. Thirdly, the addition of organic carbon increases the acidification of the sea, and fourth, the sediments are deposited on the seabed or are transported to the open ocean. This has direct consequences for the biology of the sea.”