HR: 1340h
AN: G43B-1210    [Abstracts]
TI: Modeling and Observation of Time-Variable GPS Site Positions
AU: * Gegout, P
EM: Pascal.Gegout@eost.u-strasbg.fr
AF: EOST/IPGS UMR7516 CNRS-ULP, 5 rue Descartes, Strasbourg, 67084, France
AU: Boy, J
EM: jpboy@eost.u-strasbg.fr
AF: EOST/IPGS UMR7516 CNRS-ULP, 5 rue Descartes, Strasbourg, 67084, France
AU: Hinderer, J
EM: Jacques.Hinderer@eost.u-strasbg.fr
AF: EOST/IPGS UMR7516 CNRS-ULP, 5 rue Descartes, Strasbourg, 67084, France
AU: Fehrat, G
EM: Gilbert.Ferhat@eost.u-strasbg.fr
AF: INSA de Strasbourg, 24 blvd de la Victoire, Strasbourg, 67084, France
AB: Our aim is to investigate loading consequences on the time-variable GPS site positions of hundred stations around the world during the period 2003-2006. We model the three dimensional site displacements using a Love number formalism to describe the elastic deformation of a spherical Earth's model submitted to atmospheric, oceanic and hydrological loadings. We produce site positions time series using the GPS analysis software GAMIT/GLOBK with/without inserting a combination of loading models and study their impact on 3D site positions. We first of all compare the variability of modeled and observed sites positions (without loading in the GAMIT Software). We secondly study the variance reduction in the GPS sites positions provided by the loading process. We conclude that the seasonal variability of sites displacements is quite well explained by our model in several geographic regions, e.g. at mid-latitudes in the northern hemisphere, while it is much less understood at other locations, e. g. near coastal areas.
DE: 1223 Ocean/Earth/atmosphere/hydrosphere/cryosphere interactions (0762, 1218, 3319, 4550)
DE: 1240 Satellite geodesy: results (6929, 7215, 7230, 7240)
DE: 1241 Satellite geodesy: technical issues (6994, 7969)
SC: Geodesy [G]
MN: 2007 Fall Meeting