Satellite altimetry is a primary source for deriving the global marine gravity field. Leveraging Ice, Cloud and Land Elevation Satellite-2 (ICESat-2) multi-beam laser altimetry, this study constructs global 1-arcminute gridded models of marine deflection of the vertical (DOV) and free-air gravity anomaly, referenced to the GRS80 ellipsoid. Because orbit inclination limits azimuthal sampling, the sparse cross-track geoid gradient coverage means the meridional component is generally more accurate than the prime-vertical component. ICESat-2’s ATLAS (Advanced Topographic Laser Altimeter System) employs a multi-beam configuration that provides high-density along-track elevation measurements together with near-simultaneous cross-track sampling, enabling robust constraints on cross-track geoid gradient. To mitigate this anisotropy, we implement an optimized fusion that combines the meridional component estimated from along-track geoid gradients with the prime-vertical component estimated from cross-track geoid gradients, yielding a directionally balanced DOV model. This fusion improves component-wise accuracy and enhances the stability and overall accuracy of the gravity anomaly inversion. The resulting DOV and gravity anomaly models are rigorously evaluated.
Liu et al. (Sat,) studied this question.