HR: 14:40h
AN: G53A-05 INVITED    [Abstracts]
TI: Ice sheet studies with DESDynI
AU: * Rignot, E
EM: eric.rignot@jpl.nasa.gov
AF: Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91214, United States
AB: DESDynI L-band InSAR promises timely and major advances in our monitoring capability and scientific understanding of the evolution of ice sheets and glaciers. InSAR has a long history of glaciology applications which started in 1991 with the launch of ERS-1. The European Space Agency ERS-1/2 satellites demonstrated the capability of InSAR to measure ice motion, grounding line migration, downdraw of ice surfaces, ice-shelf rifting and tidal flexure, glacial surges and other essential characteristics of ice dynamics, however with limited temporal and spatial coverage. Radarsat-1 and Envisat ASAR permitted significant advances in ice motion mapping using speckle tracking techniques, and longer-term observations of glacier evolution, but missed the shorter time scale resolution of ERS-1/2 tandem data. DESDynI will offer both, with higher quality and higher frequency of visit. The higher quality stems from the higher coherence of L-band signals on snow and ice demonstrated with SIR-C and confirmed with ALOS PALSAR, which is important in high- acumulation coastal sectors. Higher frequency of re-visit stems from the 8-day repeat and a plan to systematically acquire data with controlled baselines. ALOS PALSAR early results in West Antarctica and Greenland are very encouraging, with more data to come.Yet ALOS PALSAR 46-day repeat limits its capability to observe short-terms events e.g. calving, grounding line migration, tidal modulation in glacier velocity, downdraw consecutives to changes in basal sliding or subglacial drainage, which are important to observe to characterize the impulse response of glaciers to climate perturbations. DESDynI promises important discoveries and new science advances that are not possible with existing and planned InSAR missions. These advances will be a pillar for the development of more realistic numerical ice sheet models capable of realistic predictions of their evolution in a continously warming climate. This work was performed at Caltech's Jet Propulsion Laboratory under a contract with the National Aeronautics and Space Administration.
DE: 0720 Glaciers
DE: 0726 Ice sheets
DE: 0728 Ice shelves
DE: 0758 Remote sensing
DE: 0798 Modeling
SC: Geodesy [G]
MN: 2007 Fall Meeting