Sentinel-3 daily aggregated and outlier masked Chlorophyll-a estimates for Disko, Kobbefjord and Zackenberg GEM Stations. Sentinel-3 OLCI level 2 data, operationally processed with the Case 2 Regional CoastColor (C2RCC) processor, and further flagged, aggregated and outlier masked according to Holbach et al., 2025. Chlorophyll-a data were reprojected onto a 1Ã1 km raster in the WGS 84 / NSIDC Sea Ice Polar Stereographic North (EPSG:3413) coordinate reference system. Daily GeoTIFF images were created for the surroundings of each of the three GEM sites separately.