Estimating the true spatial resolution of satellite altimeter-derived gravity field models with shipborne data in the South China Sea

• Published in: Applied geophysics Vol. 20; no. 1; pp. 51 - 61
• Main Authors: Wang, Bo, Wu, Lin, Li, Qian-qian, Bao, Li-feng, Wang, Yong
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.03.2023; Springer Nature B.V
• Subjects: Accuracy; Altimeters; Altimetry; Earth and Environmental Science; Earth Sciences; Frequency dependence; Geophysics/Geodesy; Geotechnical Engineering & Applied Earth Sciences; Gravitational fields; Gravity data; Gravity Exploration Methods; Gravity field; Modelling; Satellite altimetry; Satellites; Spatial analysis; Spatial discrimination; Spatial resolution; South China Sea; Satellite altimetry; accuracy evaluation; shipborne gravity; marine gravity anomaly; real spatial resolution estimation
• ISSN: 1672-7975; 1993-0658
• DOI: 10.1007/s11770-023-1049-4

The launch of new altimetry satellites and ongoing updates to altimetry data have continuously improved the accuracy and resolution of satellite altimeter-derived marine gravity field models. This paper evaluates the accuracy and real spatial resolution of marine gravity field models using three different marine gravity field models (DTU17, SS V32.1, and SDUST) and two sets of shipborne gravity data in the South China Sea for a multiattribute analysis. After preprocessing and calibrating, the shipborne gravity data quality was verified using crossover analysis. The study then compared typical marine gravity models with shipborne gravity measurements to assess their accuracies in the South China Sea. Through spatial and frequency domain analyses, two methods were applied to calculate the real spatial resolutions of the gravity models. The root mean squares of deviations between the three gravity models and shipborne gravity range from 3.48–7.01 mGal, 3.38–6.80 mGal, and 2.64–6.83 mGal, and the real spatial resolution ranges of the models are 9.1–11.5 km, 6.7–11.2 km, and 8.9–11.3 km in the South China Sea area.