HR: 0830h
AN: C21B-0811    [PDF]
TI: Climate Change and Periglacial Landslide Activity in South-Western Yukon Territory
AU: * Huscroft, C A
EM: Crystal.Huscroft@gov.yk.ca
AF: Yukon Geological Survey, 2099 2nd Ave, Whitehorse, YT Y1A1B5 Canada
AU: Lipovsky, P S
EM: Panya.Lipovsky@gov.yk.ca
AF: Yukon Geological Survey, 2099 2nd Ave, Whitehorse, YT Y1A1B5 Canada
AB: Six case studies of recent landslides in southwestern Yukon Territory help predict the influence of future climate change on periglacial landslide activity in the region. The presence of permafrost and frozen ground has played an important role in each of the case studies. Permafrost degradation and thaw consolidation after recent forest fires has caused debris flows and active layer detachment slides in sub alpine and valley bottom settings. The interface between frozen and unfrozen ground has controlled the depth of movement for active layer detachment slides and debris flows in various hill slope positions. In addition, elevated pore water pressure and poor drainage due to the presence of a frozen substrate has caused debris flows in mid-slope and alpine settings. Lastly, thawing of massive segregated ice bodies has caused large thaw slumps of fine sediment in river terraces. The triggering events in each case study relate to rapid snowmelt, river migration, intense summer rainfall and permafrost degradation caused by forest fires. Climate change scenarios predict an increase in the frequency and magnitude of these incidents in south-western Yukon Territory. Therefore, a similar increase in the frequency and magnitude of periglacial landslides is expected in the region.
DE: 1600 GLOBAL CHANGE (New category)
DE: 1625 Geomorphology and weathering (1824, 1886)
DE: 1824 Geomorphology (1625)
SC: Cryosphere [C]
MN: 2003 Fall Meeting