Snow depth product on Antarctic sea ice from FengYun-3 MWRI data

This daily snow depth dataset on Antarctic sea ice at a 12.5 km resolution, derived from the brightness temperature (TB) of the Microwave Radiation Imager (MWRI) sensor aboard the FY-3B and FY-3D satellites, was produced by the Chinese Antarctic Center of Surveying and Mapping, Wuhan University. MWRI Level 1 swath data were acquired from the Chinese National Satellite Meteorological Center (http://data.nsmc.org.cn). After geolocation and calibration, all swaths TB data of one calendar day were resampled and combined into the 12.5 km polar stereographic grid. We introduced a dual-mode retrieval framework for deriving a snow depth product on Antarctic sea ice using the MWRI data. The MWRI snow depth outperformed existing passive-microwave products in accuracy, seasonal adaptability, and temporal consistency. Validation against multiple in situ datasets showed that MWRI snow depth achieved superior performance across most Antarctic regions, notably with an RMSE below 9.0 cm and a correlation coefficient above 0.70 in West Antarctica. During the melt season, validation with snow buoys yielded an RMSE of 9.94 cm, demonstrating robustness under complex surface conditions. Time-series comparisons with ICESat-2 snow depth demonstrated that the MWRI snow depth effectively captured seasonal variability (r = 0.79), accurately reproducing the winter-to-spring snow-accumulation trend. This dataset would provide a valuable snow depth record for global climate change studies or provide essential information for sea ice thickness estimation and navigation route design. The snow depth dataset from January 2012 to December 2023 are achieved in TIFF format with the date in the file name. The pixel values in the TIFF file have specific meanings: "0–70" represent snow depth in centimeters, "-1" indicates open water or missing data, and "120" indicates land.