HR: 0800h
AN: C41B-0473    [Abstracts]
TI: Assessing Elevation Changes Over Large Antarctic Subglacial Lakes From ICESat Repeat Altimetry
AU: * Shuman, C A
EM: Christopher.A.Shuman@nasa.gov
AF: Goddard Earth Science and Technology Center, University of Maryland, Baltimore County, Building 33 Room A210 NASA Goddard Space Flight Center, Greenbelt, MD 20771, United States
AU: Studinger, M
EM: mstuding@ldeo.columbia.edu
AF: Lamont-Doherty Earth Observatory of Columbia University, P.O. Box 1000, 61 Route 9W, Palisades, NY 10964, United States
AU: Bell, R E
EM: robinb@ldeo.columbia.edu
AF: Lamont-Doherty Earth Observatory of Columbia University, P.O. Box 1000, 61 Route 9W, Palisades, NY 10964, United States
AB: The recently described Recovery Lakes group (~13,300 km2) and well-known Lake Vostok (~15,690 km2) are both crossed by numerous Ice, Cloud, and land Elevation Satellite (ICESat) altimetry profiles. Since those observations have begun in late 2003 and 11 repeats of each profile have now been completed, a number of smaller lakes along East and West Antarctic ice streams have also been detected and described. However, because of the size of these large lakes as well as the Recovery Lakes relationship to the acceleration of ice into the Recovery Glacier, an assessment of their lake levels has immediate relevance to broader climate studies. Our study uses the same repeat altimetry technique to assess elevation changes at these two major subglacial lake sites. Because the elevation changes in these lake basins are not expected to be as large as the changes found under ice streams, this effort will rely on the sub-3 cm shot-to-shot precision of ICESat's laser altimeter. And to compensate for inexact repeat profiles that cross the subglacial lake topography at varying locations and angles, cross track slopes will be modeled to try to detect small but significant elevation changes. Any trends at these locations can then be evaluated in terms of lake level and potential for broader climate impact.
DE: 1817 Extreme events
DE: 1827 Glaciology (0736, 0776, 1863)
DE: 1855 Remote sensing (1640)
DE: 1872 Time series analysis (3270, 4277, 4475)
SC: Cryosphere [C]
MN: 2007 Fall Meeting