The suitability problem of the ocean tidal models used in tidal gravity observations are studied systematically in this paper. The ocean loading corrections to observations obtained with superconducting gravimeter at Wuhan station are carried out based on the ocean loading vectors calculated with a discrete numerical integral method. The numerical results show that the observed tidal gravity residuals are reduced significantly after applying to the ocean loading correction. Comparing to the theoretical ones, before and after the loading correction, the average amplitude factors for 8 main waves are reduced from 1.38% to 0.13% (Csr3.0) and 0.26% (Fes95.2) , and the average phase lag for 8 main waves are reduced from -0.485° to -0.27° (Schw80), -0.145° (Csr3.0) and -0.04° (Fes95.2). It demonstrates that those obtained from satellite altimeter technique and finite element methods can be used to eliminate effectively the influence of the ocean loading in gravity observations when using various cotidal maps. It proves the oceanic models obtained with these methods to be more reliable than the others. They can be recommended as the basic information on the ocean loading corrections for the observation study in the geodesy and geophysics.
Acta Geodaetica et Cartographica Sinica
Tidal gravity signals, Oceanic models, Superconducting gravimeter detection