Global High-resolution Marine Gravity Field Model Fused from Altimetry-derived Gravity and Shipborne Gravity

The marine gravity field is a crucial physical field of the Earth system, with shipborne and satellite altimetry-derived gravity data serving as the primary sources for its high-resolution modeling. However, shipborne gravity data is sparsely and unevenly distributed globally, while single altimetry-derived gravity models exhibit accuracy limitations or incomplete coverage in specific regions. This study utilized high-density shipborne gravity data from the Japan Agency for Marine-Earth Science and Technology (JAMSTEC) in the western Pacific Ocean (120°E－170°E, 0°－50°N). Based on the latest versions of two major global altimetry-derived gravity field models, DTU21 and SIOv32.1, it establishes correlations between the gravity model errors verified by shipborne gravity and water depths from SRTM15v2.4 model. Through weighted fusion and special processing for polar regions, a global 1'×1' gridded marine gravity anomaly model, FUSION_V1.0, was generated. This model includes longitude, latitude, and gravity anomaly variables, covering the global ocean (90°S－90°N, 180°W－180°E) and adopting the simplest and most widely used geographic coordinate system (i.e., equiangular projection), stored in NetCDF format for compatibility with mainstream scientific software. This dataset can provide high-quality foundational data for seafloor topography recovery, marine geophysical research, and related space science applications.