Corrected Shipborne Free-Air Gravity Anomaly Dataset over the China Sea and Adjacent Areas (100°E–150°E, 0°N–55°N)

This dataset contains quality-controlled shipborne free-air gravity anomaly data over the China Sea and adjacent areas (100°E–150°E, 0°N–55°N), compiled and corrected from three public sources: the National Marine Data Center (NMDC, China), the National Centers for Environmental Information (NCEI, USA), and the Japan Agency for Marine-Earth Science and Technology (JAMSTEC).

The raw data comprised 1,412 survey lines and approximately 9.16 million measurement points. Five categories of systematic errors — sign reversion, zero-value anomalies, gross errors, instrument drift, and scale factor deviation — were identified and corrected using the SWOT_02 satellite altimetry-derived gravity model as a reference. Duplicate track-lines between NMDC and NCEI were removed via cross-correlation analysis. The corrected track-lines were integrated through a crossover network adjustment to enhance internal consistency.

The final dataset comprises 557 track-lines and approximately 8.87 million data points (8,872,291 points). It achieves an internal crossover discrepancy RMS of 3.32 mGal, and standard deviations of 4.05 mGal and 4.74 mGal relative to the SWOT_02 and DTU21 gravity models, respectively.

This dataset is intended to support regional marine geophysical studies, geodetic applications, and further development of gravity field models in the China Sea region.

Data Format

All files are provided in txt format. Each file contains four columns in the following order:

Column
Field
Unit

1
Longitude
degrees (°E)

2
Latitude
degrees (°N)

3
Free-air gravity anomaly (observed, corrected)
mGal

4
SWOT_02 model interpolated value
mGal