SYSU_Topo: a 1-arc-minute global bathymetry from SWOT-derived gravity using the gravity-geological method

The Surface Water and Ocean Topography (SWOT) mission provides novel perspectives. In this study, a new global bathymetric product, SYSU_Topo, is developed using gravity anomalies (the SWOT_02 model released by Scripps Institution of Oceanography) and the high-precision gravity-geological method (GGM). The data (NetCDF format; global range from 80°S to 80°N, 1-arc-minute resolution; variables: lat, lon, z) and processing codes are openly available for immediate reuse in ocean modeling, geophysics, and seafloor mapping. To reliably obtain the optimal density contrast for GGM, a sliding-window strategy of partition inversion was adopted, and a fusion method with boundary-constraint points is developed to effectively eliminate the splicing effect of partition inversion. The model has been reliably validated with 11,167,583 single-beam bathymetric points and newly added multibeam grid points from GEBCO_2024. The SYSU_Topo model achieves superior performance in the South China Sea, with a standard deviation of 132.07 m, which is 8%-26% better than other models. Compared to traditional altimeter-derived gravity anomalies, SWOT data exhibits greater potential in filling regions lacking high-precision bathymetry.

The code of data processing is available on Zenodo at https://doi.org/10.5281/zenodo.17958256.