HR: 16:00h
AN: C34A-01    [Abstracts]
TI: Detecting Ice Shelf Grounding Zones With ICESat
AU: * Fricker, H A
EM: hafricker@ucsd.edu
AF: Scripps Institution of Oceanography, 9500 Gilman Dr, La Jolla, CA 92093 United States
AU: Padman, L
EM: padman@esr.org
AF: Earth & Space Research, 3350 SW Cascade Ave, Corvallis, OR 97333-1536 United States
AB: Since its launch in January 2003, the ICESat mission has mapped the Antarctic ice sheet to 86°S, thus covering the entire floating portion of the ice sheet including the southern parts of the Ross and Filchner-Ronne ice shelves (RIS and FRIS). We present here an application of ICESat data over ice shelves, comparisons of altimetry along repeated tracks across the grounding zones (GZ) to determine the location and flexure characteristics of the GZ. ICESat samples every ~172 m along-track with a footprint of ~65 m diameter, thus easily resolving the GZ which is typically several km wide. Differences in measured ice elevation along tracks can be used to precisely identify the grounding line (GL) and the seaward limit of the GZ, based on the limits of observed tidal flexure. By analyzing data around the perimeters of the RIS and FRIS, we can significantly improve the GL definition relative to existing estimates. By defining the flexure characteristics of the GZ, including width and curvature, it will be possible for the first time to apply tidal corrections within the GZ, which is frequently a region of intense basal melt and thus a significant focus of shelf-ice mass balance studies.
DE: 0728 Ice shelves
DE: 0730 Ice streams
DE: 0758 Remote sensing
SC: Cryosphere [C]
MN: Fall Meeting 2005