International Combination Service for Time-Variable Gravity Fields (COST-G) – Overview of Current Activities and Future Perspectives
Event: 2022 Ocean Surface Topography Science Team Meeting
Session: Precision Orbit Determination
Presentation type: Type Poster
Contribution: PDF file
The International Combination Service for Time-variable Gravity Fields (COST-G) is a Product Center of IAG’s International Gravity Field Service (IGFS). COST-G provides consolidated monthly global gravity fields in terms of spherical harmonic coefficients and thereof derived grids of surface mass changes by combining existing solutions or normal equations from COST-G analysis centers (ACs) and partner analysis centers (PCs). The COST-G ACs adopt different analysis methods but apply agreed-upon consistent processing standards to deliver time-variable gravity field models from GRACE/GRACE-FO low-low satellite-to-satellite tracking (ll-SST) and from Swarm GPS high-low satellite-to-satellite tracking (hl-SST). The poster presents the organizational structure of COST-G and results from the first releases of combined monthly GRACE and GRACE-FO solutions. In addition, the perspectives from the provision of deterministic signal models (DSM), allowing for a few months prediction and therefore application in operational precise orbit determination activities of low Earth satellites, are discussed.