Most of Arctic's Near-Surface Permafrost May Thaw by 2100

December 19, 2005

BOULDER—Global warming may decimate the top 10 feet (3 meters) or more of perennially frozen soil across the Northern Hemisphere, altering ecosystems as well as damaging buildings and roads across Canada, Alaska, and Russia. New simulations from the National Center for Atmospheric Research (NCAR) show that over half of the area covered by this topmost layer of permafrost could thaw by 2050 and as much as 90 percent by 2100. Scientists expect the thawing to increase runoff to the Arctic Ocean and release vast amounts of carbon into the atmosphere.

The study, using the NCAR-based Community Climate System Model (CCSM), is the first to examine the state of permafrost in a global model that includes interactions among the atmosphere, ocean, land, and sea ice as well as a soil model that depicts freezing and thawing. Results appear online in the December 17 issue of Geophysical Research Letters.