Ice, Ice Scraping

Antarctic icebergs scraping seafloor bare more often due to climate change

Posted at 7:14 AM on 18 Jul 2008

The warming Antarctic is changing life on the seafloor as well as above as icebergs freed from surrounding sea ice earlier than in previous years can pummel bottom-dwelling creatures for much of the year, according to a new study. "Our results suggest that as the winter sea-ice season shortens, the thousands of icebergs that float around the coastline of the Antarctic Peninsula will be free to move around and collide with the seabed creatures with ever increasing frequency," said lead author Daniel Smale of the British Antarctic Survey. The pummeling can completely reorganize life on the ocean floor where about 80 percent of Antarctic critters live. A large increase in berg scraping could potentially affect the distribution of key species and also the type and number of critters living on the seafloor. However, life does eventually return to the berg-raked areas. "Think of it like a forest," said David Barnes of BAS. "The weedy species that are normally crowded out and out-competed by the dominant species persist where big trees fall and create a clearing."

sources:  National Geographic News, Agence France-Presse, ScienceDaily
see also, in Grist:  Melting Antarctic glaciers may be releasing DDT, says study