Monitoring Sea Surface Salinity Variability Near South Greenland from Satellite and In Situ Observations

Our study focuses on the variability of Sea Surface Salinity (SSS) near south Greenland. This is based on extensive in situ data gathered from a variety of sources, including Argo floats, CTD casts, thermosalinographs, and drifters, as well as the satellite-derived SSS product from the Climate Change Initiative (CCI). The CCI SSS effectively captures a significant portion of the salinity’s seasonal and interannual variability beyond 50km from the coast, outperforming SSS from individual satellite missions. The examination of a well-sampled fresh blob in fall 2021 suggests that satellite SSS is a valuable tool for studying freshwater transfer from the shelves to the deeper ocean, particularly during ice-free periods. However, we found positive biases in the CCI SSS on the shelves, highlighting the need for improved absolute calibration in these areas. For a more detailed study of SSS within 50km of the coast, a satellite SSS with a higher spatial resolution would be required.