Radar Altimetry Derived Sea Level Anomalies – The Benefit of New Orbits and Harmonization

Most of today’s sea level studies are using the recent and high quality data of JASON-1 and TOPEX/Poseidon. Previous missions, like, e.g., ERS-1 or GEOSAT, show significant higher noise and errors. One of the main error sources is the orbit determination. In this study new GEOSAT orbits have been derived using new models and orbit determination strategies. With the new orbits the accuracy in terms of cross-over RMS is reduced from 15 to 9 cm RMS, which is almost the level of ERS-2. In addition, the orbit accuracy becomes more uniform for both the Geodetic Mission and Exact Repeat Mission period. The effects of recomputed satellite orbits on sea-level anomalies are shown.     «

Most of today’s sea level studies are using the recent and high quality data of JASON-1 and TOPEX/Poseidon. Previous missions, like, e.g., ERS-1 or GEOSAT, show significant higher noise and errors. One of the main error sources is the orbit determination. In this study new GEOSAT orbits have been derived using new models and orbit determination strategies. With the new orbits the accuracy in terms of cross-over RMS is reduced from 15 to 9 cm RMS, which is almost the level of ERS-2. In addition,...     »