A mascon adjustment of the Earth's gravity field using GOCE gradiometer data

摘要

We have subtracted known contributions from the GOCE gradiometer data that forms the basis of the fourth generation time-wise gravity field solution (TIM4), and mapped the residuals onto a local mascon model covering the south of Norway. Quasigeoids derived from combinations of the mascon adjusted TIM4 solution and EGM08 were then compared to height anomalies of a precise and dense GPS/levelling network. It was found that a mascon adjustment of TIM4 based on the first satellite cycle could improve the consistency between the corresponding quasigeoid and the network by about 0.5 cm. If the data foundation of the mascon solution was expanded to include also the next two-three satellite cycles then an improved consistency between the corresponding quasigeoid and the network height anomalies appeared on all spatial scales.