HR: 0830h
AN: C21B-0822    [PDF]
TI: Warming and Thawing of Permafrost in Alaska: Recent Results and Impacts
AU: * Osterkamp, T E
EM: ffteo@uaf.edu
AF: Geophysical Institute, University of Alaska, Fairbanks, AK 99775 United States
AB: There has been a widespread warming of air temperatures in Alaska since 1977 and some warming of permafrost. Constant or cooling permafrost temperatures followed this in the early 1980s, probably due to thin snow covers and a short cooling trend. Permafrost temperatures along a north south transect from Prudhoe Bay to Gulkana and at other sites have generally warmed since the late 1980s, initially in response to thicker snow covers. The warming north of the Brooks Range is comparable in magnitude to the century long warming there (2 to 4$\deg$C). The trend has not been followed at Eagle and the Yukon River bridge. Warming of the discontinuous permafrost is typically $\frac{1}{2}$ to 1$\frac{1}{2}\deg$C. Thin discontinuous permafrost is thawing at the base at a rate of 0.04 m per year at one site. New thermokarst and thawing permafrost have been observed at several sites. Significant impacts of warming and thawing permafrost and thermokarst on the environment, ecosystems and on infrastructure will be presented.
DE: 1615 Biogeochemical processes (4805)
DE: 1823 Frozen ground
DE: 1863 Snow and ice (1827)
DE: 3322 Land/atmosphere interactions
DE: 3344 Paleoclimatology
SC: Cryosphere [C]
MN: 2003 Fall Meeting