HR: 08:00h
AN: G31A-01 INVITED    [Abstracts]
TI: Global Surface Mass Variations From GRACE, GPS, and Geophysical Models
AU: * Wu, X
EM: Xiaoping.Wu@jpl.nasa.gov
AF: Jet Propulsion Laboratory, CALTECH, 4800 Oak Grove Drive, MS 238-600, Pasadena, CA 91109, United States
AU: Gross, R S
EM: Richard.S.Gross@jpl.nasa.gov
AF: Jet Propulsion Laboratory, CALTECH, 4800 Oak Grove Drive, MS 238-600, Pasadena, CA 91109, United States
AU: Heflin, M B
EM: Michael.B.Heflin@jpl.nasa.gov
AF: Jet Propulsion Laboratory, CALTECH, 4800 Oak Grove Drive, MS 238-600, Pasadena, CA 91109, United States
AU: Ivins, E R
EM: Erik.R.Ivins@jpl.nasa.gov
AF: Jet Propulsion Laboratory, CALTECH, 4800 Oak Grove Drive, MS 238-600, Pasadena, CA 91109, United States
AU: Schotman, H H
EM: hugo@deos.tudelft.nl
AF: DEOS - TU Delft, Kluyverweg 1, Delft, NL -2629 HS, Netherlands
AU: Vermeersen, B L
EM: L.L.A.Vermeersen@tudelft.nl
AF: DEOS - TU Delft, Kluyverweg 1, Delft, NL -2629 HS, Netherlands
AB: Non-steric sea-level change, Greenland, Antarctica and mountain glacial mass fluctuations and land hydrological cycles are all important parts of the global surface mass variation process with significant societal impact. Currently, no single geodetic technique or system can monitor these changes with complete spatiotemporal coverage. Studies of present-day surface mass trends are further frustrated by the duality of signatures of these trends and Glacial Isostatic Adjustment (GIA). Lack of reliable geocenter velocity estimate presents another serious problem. However, multi-satellite data from different geodetic techniques contain complementary spatiotemporal information. Also, the present-day surface mass trends and historical mass variations produce distinct signatures in different data types. Therefore, combination of multi-satellite geodetic and interdisciplinary data offers the best chance to separately determine the present-day mass trends, ice-water history, and Earth rheology with less ambiguity, better resolution and accuracy. We conduct global inversions for present-day surface mass variations in spherical harmonic domain using combinations of GRACE, GPS, a TOPEX/Poseidon/Jason-1 data-assimilated ocean bottom pressure model, and models of atmosphere, hydrology and GIA. The resulting coefficients with a complete spectrum up to degree and order 50 are then used to study global patterns and regional averages. Strategies and significance of further data combinations in the future will also be discussed.
DE: 1217 Time variable gravity (7223, 7230)
DE: 1218 Mass balance (0762, 1223, 1631, 1836, 1843, 3010, 3322, 4532)
DE: 1225 Global change from geodesy (1222, 1622, 1630, 1641, 1645, 4556)
DE: 1240 Satellite geodesy: results (6929, 7215, 7230, 7240)
DE: 1645 Solid Earth (1225)
SC: Geodesy [G]
MN: 2007 Fall Meeting