HR: 1340h
AN: G33C-0057    [Abstracts]
TI: Regional high-resolution spatio-temporal gravity modeling from GRACE data using spherical wavelets
AU: Kusche, J
EM: j.kusche@lr.tudelft.nl
AF: DEOS, Delft University of Technology, Kluyverweg 1, Delft, 2600 GB Netherlands
AU: Schmidt, M
G33C-0057 AF: Deutsches Geodaetisches Forschungsinstitut (DGFI), Marstallplatz 8, Munich, D-80539 Germany
AU: Han, S
G33C-0057 AF: Laboratory for Space Geodesy and Remote Sensing, The Ohio State University, 470 Hitchcock Hall 2070 Neil Avenue, Columbus, OH 43210 United States
AU: Sanchez, L
G33C-0057 AF: Deutsches Geodaetisches Forschungsinstitut (DGFI), Marstallplatz 8, Munich, D-80539 Germany
AU: * Shum, C
G33C-0057 AF: Laboratory for Space Geodesy and Remote Sensing, The Ohio State University, 470 Hitchcock Hall 2070 Neil Avenue, Columbus, OH 43210 United States
AU: Xie, J
G33C-0057 AF: Laboratory for Space Geodesy and Remote Sensing, The Ohio State University, 470 Hitchcock Hall 2070 Neil Avenue, Columbus, OH 43210 United States
AB: This paper deals with the application of the multi-resolution technique based on spherical wavelet theory to determine regional spatio-temporal gravity models using spaceborne gravimetry data (GRACE, GOCE). The basic idea of the multi-resolution representation is to split an input gravity signal into a number of detail signals. Since each detail signal (levels) is related to a special frequency-band it is in fact computable from different data sets covering specific parts of the frequency spectrum. In our approach we estimate at first the long-wavelength (low-level) part of the gravity field using in situ potential measurements derived from GRACE inter-satellite range-rate and accelerometer measurements using the energy conservation approach. This way we obtain both wavelet based regional and temporal gravity fields with spatial resolution up to ~300 km and varying sampling (each detail signal is computed from a GRACE data frame of different length; between several days for the long wavelengths to a month for the more detailed structures) as well as a mean gravity field model based on more than two years of GRACE data. Solution constraints, when necessary, are implemented in a data-driven optimal procedure. For the static case we compute in addition the high-level detail signals or short-wavelength gravity components, where available, from Faye anomalies derived from terrestrial, airborne and altimetric observations. Since the medium-level detail signals are present in both the satellite and in the surface data they require the use of a combination method. As an example, we apply the developed procedures to determine a regional time-dependent gravity model of the Amazon basin, a mean high-resolution gravity model for Colombia, and other selected regions. It is anticipated that the developed methodologies can be applied to other regions of interest and have the distinct capability of spatial and temporal signal enhancement using the multi-resolution representation of the gravity field model.
DE: 1200 GEODESY AND GRAVITY
DE: 1214 Geopotential theory and determination (0903)
DE: 1217 Time variable gravity (7223, 7230)
DE: 1218 Mass balance (0762, 1223, 1631, 1836, 1843, 3010, 3322, 4532)
SC: Geodesy [G]
MN: Fall Meeting 2005