HR: 10:20h
AN: C22A-01 INVITED     [Abstracts]
TI: GLAS observations of Antarctic ice shelf features: The vertical dimension
AU: * Fricker, H A
EM: hafricker@ucsd.edu
AF: Institute of Geophysics and Planetary Physics, Scripps Institution of Oceaongraphy, 9500 Gilman Drive, La Jolla, CA 92093 United States
AU: Bassis, J
EM: jbassis@ucsd.edu
AF: Institute of Geophysics and Planetary Physics, Scripps Institution of Oceaongraphy, 9500 Gilman Drive, La Jolla, CA 92093 United States
AU: Minster, B
EM: jbminster@ucsd.edu
AF: Institute of Geophysics and Planetary Physics, Scripps Institution of Oceaongraphy, 9500 Gilman Drive, La Jolla, CA 92093 United States
AB: Since the launch of ICESat in January 2003, the Geoscience Laser Altimeter System (GLAS) has provided glaciologists with unprecedented topographic information for Antarctica, delivering elevation profiles containing exquisite detail. GLAS's small footprint (65m) reveals many important ice shelf features which had been heretofore unresolved by large-footprint satellite radar altimeters. For example, not only are we able to measure accurately the width of rifts that cut across ice shelves, but by careful re-tracking of individual GLAS waveforms we can also measure the thickness of the ice m\'{e}lange that fills these rifts and estimate how this changes with time. We illustrate this using several rifts of various ages on the Ross and the Amery Ice Shelves. GLAS also yields substantial advances over previous measurements of the topography of ice shelf fronts: the same re-tracking procedure allows us not only to locate the ice front along the ICESat ground track very precisely, but also to resolve topographic signatures across the front of some ice shelves which are consistent with significant basal melting.
DE: 1694 Instruments and techniques
DE: 1827 Glaciology (1863)
DE: 1640 Remote sensing
SC: Cryosphere [C]
MN: 2004 AGU Fall Meeting