SYSU_Topo: SWOT-derived global bathymetric model

The Surface Water and Ocean Topography (SWOT) mission provides novel perspectives for ocean observations, including ocean dynamics, marine gravity, and seafloor topography. In this study, we employed the high-precision gravity-geological method and developed an inversion strategy using sliding windows with boundary constraint points, focusing on the global region between 180°W–180°E and 80°S–80°N. Using gravity anomalies from the grav_SWOT_02 model (released by Scripps Institution of Oceanography), we constructed the global seafloor topography model SYSU_Topo with 1 arc-min resolution. The model was validated with approximately 11,167,583 independent single-beam bathymetric points and newly added multibeam grid points from GEBCO_2024. Results show that SYSU_Topo has 87% absolute errors ≤100 m and 89% relative errors ≤5% in single-beam validation, with minimal and concentrated error distribution. In multibeam validation, the five compared models demonstrate regional advantages, where SYSU_Topo shows significant improvement in the South China Sea—an area with sparse early-stage data. Compared to traditional altimeter-derived gravity anomalies, SWOT data exhibits greater potential in filling regions lacking high-precision bathymetry, thereby enhancing seafloor topography inversion accuracy. Even when modelled solely with single-beam data, the SYSU_Topo model achieves reliable precision. This research provides a new benchmark framework for integrating multi-source bathymetric data to construct high-resolution seafloor topography, contributing to the advancement of global ocean mapping efforts.