基于卫星测高重力数据提升北极海底地形模型精度方法的研究OA

Improving the accuracy of Arctic seafloor topographic model is of great significance for research on Arctic shipping lanes.The IBCAO V4.2 model with its fusion of multi-source sonar data occupies an im-portant position in Arctic-related research fields.However,the construction of a seafloor topographic model by combining bathymetry data and gravity data has advantages over the construction of a model based on bathymetry data alone.The gravity-geologic method(GGM)effectively combines bathymetric and gravity data to construct seafloor topographic models.This study aimed to use the GGM to solve the deformation of the geographic grid and the key parameter density difference in the construction of the seafloor topographic model in the Arctic sea.This study proposed a method to solve the density difference constant by regression analysis under the polar spherical projection condition,and then invert the seafloor topography using the GGM.The eastern part of the Greenland Sea was used as the test area,and the SDUST_GA_2022 satellite data and part of the shipborne measured bathymetry data were combined to construct the AO1-GGM mod-el—a seafloor topographic model that covers approximately 7.6×104 km2.The model was externally vali-dated using shipboard measured bathymetry data and compared with the IBCAO V4.2 model and the AO1-GGM model constructed based only on shipboard-measured bathymetry data.The results showed that:(1)in the region where shipboard-measured bathymetry data are lacking,the AO1-GGM model draws topo-graphic details with the help of ocean gravity anomalies in the polar region,and performs better than the AO1-Grid model.(2)Compared with the IBCAO V4.2 model,the AO1-GGM is more compatible with the actual situation and has better results in the checking of the assessment indexes,such as the mean squared error and root mean squared error,with an improvement in accuracy of approximately 35.01%and a smaller degree of dispersion of the checking error.The results show that the accuracy of the Arctic seafloor topog-raphy model was improved by integrating multi-source sonar and satellite altimetry and gravity data.