HR: 11:05h
AN: G42A-04    [Abstracts]
TI: Subdaily Earth Rotation Models Estimated From GPS and VLBI Data
AU: * Steigenberger, P
EM: steigenberger@gfz-potsdam.de
AF: GeoForschungsZentrum (GFZ), Telegrafenberg A17, Potsdam, 14473, Germany
AU: Tesmer, V
EM: tesmer@dgfi.badw.de
AF: Deutsches Geodätisches Forschungsinstitut (DGFI), Alfons-Goppel-Str. 11, München, 80539, Germany
AU: MacMillan, D
EM: dsm@leo.gsfc.nasa.gov
AF: NVI, Inc./Goddard Space Flight Center (GSFC), Code 698, Greenbelt, MD 20771, United States
AU: Thaller, D
EM: thaller@gfz-potsdam.de
AF: GeoForschungsZentrum (GFZ), Telegrafenberg A17, Potsdam, 14473, Germany
AU: Rothacher, M
EM: rothacher@gfz-potsdam.de
AF: GeoForschungsZentrum (GFZ), Telegrafenberg A17, Potsdam, 14473, Germany
AU: Fritsche, M
EM: fritsche@ipg.geo.tu-dresden.de
AF: Institut für Planetare Geodäsie, TU Dresden, Helmholtzstr. 10, Dresden, 01062, Germany
AU: Rülke, A
EM: ruelke@ipg.geo.tu-dresden.de
AF: Institut für Planetare Geodäsie, TU Dresden, Helmholtzstr. 10, Dresden, 01062, Germany
AU: Dietrich, R
EM: dietrich@ipg.geo.tu-dresden.de
AF: Institut für Planetare Geodäsie, TU Dresden, Helmholtzstr. 10, Dresden, 01062, Germany
AB: Subdaily changes in Earth rotation at diurnal and semi-diurnal periods are mainly caused by ocean tides. Smaller effects are attributed to the interaction of the atmosphere with the solid Earth. As the tidal periods are well known, models for the ocean tidal contribution to high-frequency Earth rotation variations can be estimated from space- geodetic observations. The subdaily ERP model recommended by the latest IERS conventions was derived from an ocean tide model based on satellite altimetry. Another possibility is the determination of subdaily ERP models from GPS- and/or VLBI-derived Earth rotation parameter series with subdaily resolution. Homogeneously reprocessed long-time series of subdaily ERPs computed by GFZ/TU Dresden (12 years of GPS data), DGFI and GSFC (both with 24 years of VLBI data) provide the basis for the estimation of single-technique and combined subdaily ERP models. The impact of different processing options (e.g., weighting) and different temporal resolutions (1 hour vs. 2 hours) will be evaluated by comparisons of the different models amongst each other and with the IERS model. The analysis of the GPS and VLBI residual signals after subtracting the estimated ocean tidal contribution may help to answer the question whether the remaining signals are technique-specific artifacts and systematic errors or true geophysical signals detected by both techniques.
DE: 1222 Ocean monitoring with geodetic techniques (1225, 1641, 3010, 4532, 4556, 4560, 6959)
DE: 1223 Ocean/Earth/atmosphere/hydrosphere/cryosphere interactions (0762, 1218, 3319, 4550)
DE: 1239 Earth rotation variations
DE: 1240 Satellite geodesy: results (6929, 7215, 7230, 7240)
DE: 6924 Interferometry (1207, 1209, 1242)
SC: Geodesy [G]
MN: 2007 Fall Meeting