HR: 08:15h
AN: C11A-02    [PDF]
TI: Permafrost: An International Approach to 21th Century Challenges
AU: * Brown, J
EM: jerrybrown@igc.org
AF: International Permafrost Association, P. O. Box 7, Woods Hole, MA 02543 United States
AB: Whereas glaciers are easily discernible to the human eye and satellites, permafrost terrains and their physical components are not easily detected from the surface without supplemental knowledge and measurements. In the Northern Hemisphere, approximately 17 million km$^{2}$ of exposed land contains some extent of permafrost or ground that remains frozen for more than two years. The vast majority, or 11 million km$^{2}$, of permafrost terrain has temperatures of 5$\deg$ C or below, with perennially frozen ground underlying essentially all ground surfaces to considerable depths. Permafrost in the remaining regions, including mid-latitude mountains, is both warmer and is spatially variable (discontinuous). As climate warms the uppermost permafrost is subjected to increase thaw with resulting ground subsidence, accelerated erosion, and related biogeochemical modifications. The challenging questions to geocryologists, modelers and the public relate to the rate of change and the spatial variability of the projected thaw, particularly in the warmer zones where actual areal and subareal distribution of permafrost is poorly known. An international network of active layer measurements and borehole sites now exists under the Global Climate Observing System (GCOS), but requires additional sites for representative coverage. This Global Terrestrial Network for Permafrost (GTN-P) is coordinated by the 24-member, International Permafrost Association. At the Eighth International Conference on Permafrost (ICOP) in Zurich in July 2003, the IPA Council agreed on the scope of new activities for the next five years, many of which will be undertaken in cooperation with other international organizations (e.g. WCRP/CliC; ICSI, IASC, SCAR, IGU, IUGS). Examples of the activities of the IPA Working Groups are:\\ 1. Antarctic Permafrost and Periglacial Environments (active layer processes, maps, database).\\ 2. Coastal and Offshore Permafrost (sediment and organic transfers, subsea permafrost dynamics).\\ 3. Cryosol (Antarctic soil map, soil database).\\ 4. Glacier and Permafrost Hazards in High Mountains (interaction of ice and permafrost on slopes).\\ 5. Isotopes and Geochemistry of Permafrost (paleo-reconstruction, modern processes).\\ 6. Mapping and Modelling of Mountain Permafrost (standardize map legends and maps, multi-dimensional models).\\ 7. Periglacial Processes and Environments (past and present processes, field manual of measurements).\\ 8. Permafrost and Climate (monitoring, impact assessments, inter-comparisons of models).\\ 9. Permafrost Astrobiology (survivability of life on planets and analogous Earth environments).\\ 10. Permafrost Engineering (case studies, climate impacts on infrastructure).\\ The Data Committee facilitates recovery of data, web access, and CD data production. These activities will provide added insight into past, present and future occurrences and responses of permafrost to climate change. They can contribute to activities of the International Polar Year. Results will be reported at the Ninth ICOP in Fairbanks, Alaska, in summer 2008. Current information is available on the IPA web site and in annual issues of {\it Frozen Ground}.
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