Evaluations of the Recent Goce-Based Gravity Field Models
1〓Xi’an Division of Surveying and Mapping, 36 Xiying Road,Xi’an 710054, China
2〓State Key Laboratory of Geodesy and Earth’s Dynamics,340 Xudong Street, Wuhan 430077, China
3〓School of Geosciences and Info-Physics, Central South University,932 South-Lushan Road, Changsha 410083, China
Abstract:Three kinds of GOCE-based gravity field models, i.e. time-wise models, space-wise models and direct approach models released by ESA, are evaluated from three schemes including accumulative geoid errors, geoid height differences and combination of the models in different spectral bands. Results from spectral analyses and GPS/leveling geoid difference in North America indicate that, the 4th generation model from direct approach satisfies the GOCE mission objective of achieving ±1 cm geoid accuracy at a spatial resolution of approximately 100 km. The direct approach models have the better performance compared to time-wise models and space-wise models. GOCE data products can improve the accuracy of middle to high spectral band signals of gravity fields.