Using satellite altimetry leveling to assess the marine geoid

Abstract

Based on the concept of Global Position System (GPS)/leveling, the satellite altimetry leveling (SAL) is first proposed to evaluate the marine geoid. SAL is derived by the difference among the mean sea surface (MSS), mean dynamic ocean topography (MDT), and leveling origin. In this study, (1) the original satellite altimetry data are processed to infer the vertical deflection and gravity anomaly, (2) the Chinese coastal marine geoids (CMG) are determined by using the different methods (including Molodensky, least square collocation, Stokes formula, and two-dimensional fast Fourier transformation (FFT) with the vertical deflection and gravity anomaly data), (3) CMG are evaluated by using the results from above different methods, the Gravity field and steady-state Ocean Circulation Explorer (GOCE) gravity potential model (GGPM), and SAL. The results show that (1) CMG from the Molodensky method has the highest precision by using vertical deflection data, (2) the accuracy of CMG indicate good consistency between the SAL and GGPM, (3) SAL can be used as a new method for assessing marine geoid. Keywords: Satellite altimetry leveling, Marine geoid, Vertical deflection, Gravity anomaly