The status of the NASA GSFC altimeter satellite orbits for TOPEX, the Jason satellites and Sentinel-6A
Event: 2023 Ocean Surface Topography Science Team Meeting
Session: Precision Orbit Determination
Presentation type: Type Oral
Contribution: PDF file
The main goal of our precise orbit analyses is to compute a series of precise orbits from 1993 to the present, for the reference altimetry missions (TOPEX/Poseidon, the Jason satellites and Sentinel-6A) with a consistent set of geophysical standards. We describe the status of the current generation of std2006 series of orbits, and efforts to implement a new set of operational standards. In contrast to the other analysis centers, we rely on a more dynamic orbit parameterization using SLR and DORIS data. We describe the impact of various improvements including updates to the International Terrestrial Reference Frame (ITRF), and updates to different aspects of the force and measurement models. We review the impact of these changes on POD performance through comparisons with solutions from other analysis centers, independent altimeter crossovers. We show the impact of the new orbits on the computation of global mean sea level, with a special focus on the altimeter product consistency during the tandem mission phases. We also compare the NASA GSFC SLR/DORIS orbits for Sentinel-6A with GNSS precise orbits computed at NASA GSFC with GPS & Galileo data.