Application of satellite altimetry technique in marine gravity surveying
(1.Dalian Naval Academy, Dalian 116018, China2.Central South University, Changsha 410083, China3.Department of Ocean Surveying, Dalian Naval Academy, Dalian 116018, China)
Abstract: Satellite altimetry can provide the geoid in ocean areas with a level of precision of about 10 cm. Such a precise geoid offers a good opportunity for studying the marine gravity field. The basic mathematical model and theory of the satellite altimetry were introduced briefly and firstly. Then the inverse Hotine method to derive gravity disturbances from satellite altimetry was presented. Meanwhile the inversion of marine gravity in Chinese coastal waters from Topex/Poseidon satellite altimetry data was tested, and the RMS between the gravity disturbance from the OSU91A model and satellite altimetry data inversing is about 12.76 mGal. Finally, some problems which are in inversing procedure were discussed, i e, integration singularity, edge effect etc. And it is conluded that the accuracy of the inversing gravity method can reach only a few mGal if proper treatment of Fast Fourier Transform (FFT) edge effect is employed.
Key words: satellite altimetry； data inversion； gravity disturbance