SGG-UGM-1: the high resolution gravity field model based on the EGM2008 derived gravity anomalies and the SGG and SST data of GOCE satellite

SGG-UGM-1 is a global gravity field model computed by the combination of EGM2008 gravity anomalies and GOCE SGG,SST data Input data:-- EGM2008 derived gravity anomalies (5' x 5' resolution)-- GOCE SGG data: EGG_NOM_2 (GGT: Vxx, Vyy, Vzz) in GRF-- GOCE SST data: SST_PKI_2, SST_PCV_2, SST_PRD_2 Processing procedure:-- Block-diagonal normal equation system up to degree and order 2159 are formed with EGM2008 gravity anomaly data using block-diagonal least squares method. -- Fully occupied normal equation system up to degree and order 220 are formed by GOCE SGG data and the SST observations along the GOCE orbit based on least-squares analysis. The diagonal components (Vxx, Vyy, Vzz) of the gravitational gradient tensor are used to form the system of observation equations with the band-pass ARMA filter. The point-wise acceleration observations (ax, ay, az) along the orbit are used to form the system of observation equations up to the maximum spherical harmonic degree/ order 130.-- SGG-UGM-1 is resolved by combining the two normal equation systems using the least-squares method.