Accurate Correction Models for Tidal Gravity in Chinese Continent

AbstractAccurate correction models for tidal gravity in Chinese continent are developed by using the recent theoretical and experimental models for the Earth's tidal gravity, in which the loading effects of the global and local ocean tides are combined. The relative difference of tidal gravity variations induced from different Earth's tidal gravity models is less than 0.06%. The ocean tide loading effects are about 4% of the total tidal gravity in coastal area while they are about 1% in inland. The difference between the ocean tide loading effects estimated from global ocean tide models and modified global models with local tides is about 10% of the total ocean tide loading effects. And the interpolated and extrapolated ocean tide loading effects are about 3% of the total ones. Comparing the observed tidal gravity variations by superconducting gravimeter with the ones calculated through the correction models, it is confirmed that the models developed in this study can accurately predict the tidal gravity signatures with a precision much better than 0.5 × 10−8 m·s−2. Consequently, it is expected that the models should provide an effective reference and accurate correction models for gravity measurements.