HR: 11:25h
AN: C22A-05    [Abstracts]
TI: Permafrost in a Changing Climate: Russian Prospective
AU: * Anisimov, O A
EM: oleg@OA7661.spb.edu
AF: State Hydrologial Institute, 23, Second Line V.O., St.Petersburg, 199053 Russian Federation
AU: Shiklomanov, N I
EM: shiklom@UDel.edu
AF: Department of Geography, Center for Climatic Research, University of Delaware, 12, Academy Street, Newark, DE 19716 United States
AB: Permafrost models predict significant impact of changing climate on the distribution, temperature, and active-layer thickness (ALT) of the frozen ground. Contrasting these results, observations indicate degradation of permafrost in some locations, while in many others permafrost patterns are relatively stable under warmer climate. We compare the results from modeling and observations at CALM sites in Russian permafrost regions and study the sensitivity of permafrost models to forcing climate data. We used the equilibrium permafrost model of the Russian Hydrological Institute/University of Delawre, three different baseline forcing data sets, and five scenarios of climate change from GFDL, ECHAM, NCAR, CCC, and HadCM GCMs. There was a general agreement between the computational results and CALM data on ALT variability in the last 10 years at most of the Russian sites. At several Russian sites the non-climatic factors, such as complex vegetation composition and soil moisture conditions, disturb the "average" ALT pattern. Effects of such factors are likely to increase under the projected for the future climate, and further field and modeling studies are needed to represent them with sufficient level of detail. Calculations indicated high sensitivity of the model to the forcing climatic data. Discrepancies between the results obtained with three different baseline data sets in several regions exceeded the projected under the five climatic scenarios mid-21st century changes of the ALT.
DE: 4540 Ice mechanics and air/sea/ice exchange processes (0700, 0750, 0752, 0754)
SC: Cryosphere [C]
MN: Fall Meeting 2005