Quality Assessment and Correction of Shipborne Gravity Data over the China Sea and Its Adjacent Areas

Shipborne gravity data are fundamental for marine geoscience but often suffers from significant quality discrepancies due to varying measurement and processing techniques. This study proposed a data processing procedure to evaluate and correct the shipborne gravity anomaly data from NCEI (National Centers for Environmental Information), NMDC(National Marine Data Center), and JAMSTEC(Japan Agency for Marine-Earth Science and Technology) over the China Sea and its adjacent areas (100°E–150°E, 0°N–55°N). Using the SWOT_02 model as a reference, five types of errors were identified and corrected. Following this rigorous quality control process, 10 track-lines and 104,160 data points were rejected from the NMDC&NCEI dataset, while 1 track-line and 181,072 data points were removed from the JAMSTEC track-lines dataset. Consequently, a refined, high-quality shipborne gravity anomaly dataset comprising 557 track-lines and approximately 8.87 million measurement points was established. The new dataset exhibits an internal crossover discrepancy (XOD) RMS of 3.32 mGal and STD of 4.05 mGal and 4.74 mGal when compared with the SWOT_02 and DTU21 model, respectively. These findings provide a valuable dataset for regional geophysical studies and a robust framework for the quality control of historical shipborne gravity anomaly data.