2023 Arctic daily 25km sea ice drift product (v1.0 version)

The "2023 Daily 25 km Arctic Sea Ice Drift Product (Version 1.0)" provides the daily 25 km Arctic sea ice drift for the year 2023. This product is stored in netCDF (.nc) format. The netCDF file comprises five variables: the projected coordinate system of this product (EPSG: 3408), the geographic location of each grid cell (defined by its X and Y coordinates within the projected coordinate system), and the sea ice velocities in the X and Y directions (units: km/day) for each grid cell within that coordinate system. Specifically, the X coordinate for each grid is a one-dimensional matrix indexed by column number j, while the Y coordinate is a one-dimensional matrix indexed by row number i. The sea ice velocities in both the X and Y directions are three-dimensional matrices indexed by (day_of_year, i, j), where day_of_year indicates the day of the year 2023 on which the drift measurement began.The product was produced using 89 GHz brightness temperature data from the Microwave Radiation Imager (MWRI) aboard the Fengyun-3D satellite. The production process primarily involves three steps: first, processing the raw MWRI swath data into gridded brightness temperature images of the Arctic; second, retrieving sea ice drift vectors by applying the maximum cross-correlation method combined with sub-pixel image matching techniques; and finally, removing potentially erroneous drift vectors based on neighborhood consistency checks.