The Copernicus Daily Cumulative Gap-filled Fractional Snow Cover (GFSC) product is generated in near real-time for the entire EEA38 and the United Kingdom, based on radar satellite data from the Sentinel-1 constellation and on optical data from the Sentinel-2 constellation. The product uses Copernicus FSC (Fractional Snow Cover), WDS (Wet/Dry Snow) and SWS (SAR Wet Snow) products along with DEM data as input to form a spatially complete composite of snow conditions, to reduce observational gaps due to clouds and lack of sensor coverage on a daily basis. The product provides the extent of the snow cover per pixel as a percentage (0% – 100%) with a spatial resolution of 60 m x 60 m.

The GFSC product is distributed in raster files covering an area of 110 km by 110 km with a pixel size of 60 m by 60 m in UTM/WGS84 projection, which corresponds to the Sentinel-2 input L1C product tile. Each product is composed of four separate GeoTIFF files corresponding to the different layers of the product, and a metadata file. The GF layer provides the gap-filled fractional snow cover, while the QC layers (AT, QCFLAGS, QC) provide information on the quality of the GF layer at the pixel level .

The GFSC is one of the products of the pan-European High-Resolution Snow & Ice service (HR-S&I), which are provided at high spatial resolution (20 m x 20 m and 60 m x 60 m), from the Sentinel-2 and Sentinel-1 constellations data from September 1, 2016 onwards. Visit https://land.copernicus.eu/pan-european/biophysical-parameters/high-resolution-snow-and-ice-monitoring to get more information on the different HR-S&I products (Snow products : FSC, WDS, SWS, GFSC, and PSA. Ice products: RLIE and ARLIE).