HR: 13:55h
AN: C33A-02    [Abstracts]
TI: Recent Elevation Changes on the Ice Streams and Ridges of the Ross Embayment From ICESat Crossovers
AU: * smith, b E
EM: ben@ess.washington.edu
AF: University of Washington, Condon Hall 310 box 351310, Seattle, WA 98195 United States
AU: Bentley, C F
EM: bentley@geology.wisc.edu
AF: University of Wisconsin, 1215 W. Dayton, Madison, WI 53706 United States
AB: We analyze differences in ICESat elevation estimates at orbital crossover locations to determine short-term rates of elevation change for small regions within the Ross Embayment of the West Antarctic Ice sheet. A linear regression of crossover elevation direrence against time difference gives an estimate of the mean elevation-change rate during the ICESat mission to date. The first 24 months of ICESat data show prevalent elevation change in the south, with uplift in the upstream end of Kamb Ice Stream at 0.24-0.30 m/a, and thinning in the parts of Whillans Ice Stream, Mercer Ice Stream, and the adjacent Conway and Engelhardt ice ridges at 0.05-0.18 m/a. These rates of elevation change are too large to be explained by the 0.02-0.03 m/a formal regression error, by seasonal height variations, or by accumulation- or densication-rate variability, suggesting that they reflect real variations stemming from ice dynamics of the region.
DE: 0762 Mass balance (1218, 1223)
DE: 0794 Instruments and techniques
SC: Cryosphere [C]
MN: Fall Meeting 2005