HR: 17:00h
AN: C44A-05    [Abstracts]
TI: Controls on advance of tidewater glaciers: Results from numerical modeling applied to Columbia Glacier, Alaska
AU: * Nick, F M
EM: f.m.nick@phys.uu.nl
AF: Institute for Marine and Atmospheric Research, Princetonplein 5, Utrecht, 3584CC Netherlands
AU: van der Veen, C J
EM: vanderveen.1@osu.edu
AF: Byrd Polar Research Center and Department of Geological Sciences, 108 Scott Hall 1090 Carmack Road, Columbus, OH 43210 United States
AB: A 1-D numerical ice-flow model is used to study the advance of a tidewater glacier into deep water. Starting with ice-free conditions, the model simulates glacier growth at higher elevations, followed by advance on land to the head of the fjord. Once the terminus reaches a bed below sea level, calving in initiated. A series of simulations was carried out with various boundary conditions and parameterizations of the annual mass balance. The results suggest that irrespective of the calving criterion and accumulation rate in the catchment area, it is impossible to have the glacier terminus advancing into deeper water (~300 m) unless some sedimentation at the glacier front is included. The advance of Columbia Glacier, Alaska, is reproduced by the model by including "conveyor-belt" recycling of subglacial sediment and the formation of a sedimentation bank at the glacier terminus. Results indicate slow advance through the deep fjord and faster advance in shallow waters approaching the terminal moraine shoal and the mouth of the fjord.
DE: 0720 Glaciers
DE: 0774 Dynamics
DE: 0798 Modeling
SC: Cryosphere [C]
MN: Fall Meeting 2005