Ulrich Meyer (University of Bern, Switzerland); Joao Teixeira da Encarnação (TU Delft, The Netherlands); Martin Lasser (University of Bern, Switzerland); Frank Flechtner (German Research Centre for Geosciences, Germany); Christoph Dahle (German Research Centre for Geosciences, Germany); Eva Boergens (German Research Centre for Geosciences, Germany); Förste Christoph (German Research Centre for Geosciences, Germany); Torsten Mayer-Gürr (TU Graz, Austria); Andreas Kvas (TU Graz, Austria); Behzadpour Saniya (TU Graz, Austria); Jean-Michel Lemoine (CNES, France); Stéphane Bourgogne (Stellar Space Studies, France); Igor Koch (University of Hannover, Germany); Matthias Duwe (University of Hannover, Germany); Jakob Flury (University of Hannover, Germany); Matthias Weigelt (University of Hannover, Germany); Heike Peter (PosiTim UG, Germany); Andreas Groh (TU Dresden, Germany); Annette Eicker (HafenCity University Hamburg, Germany); Alejandro Blazquez (LEGOS, France); Benoit Meyssignac (LEGOS, France)

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.