Copernicus Marine Global L4 Sea Surface Salinity and Density

The Copernicus Marine Global L4 Sea Surface Salinity and Density product (ID MULTIOBS_GLO_PHY_S_SURFACE_MYNRT_015_013) provides daily, globally gap-free L4 analyses of sea surface salinity (SSS) and sea surface density (SSD), distributed by the Copernicus Marine Service.^[1]

The product is produced by the Consiglio Nazionale delle Ricerche (CNR), Italy. It is generated by merging L-band satellite SSS retrievals from SMOS and SMAP with Argo float near-surface salinity profiles, applying an optimal interpolation approach to produce a complete spatial field at each daily time step.^[1] The 0.125 x 0.125 degrees global grid spans the full ocean surface and is available in near-real-time (NRT) and multiyear reprocessed (REP) streams.

Sea surface density is derived directly from the SSS and collocated sea surface temperature fields. Both variables are provided in a single NetCDF file per time step. The product is freely accessible under the Copernicus Marine open-data licence via the CMEMS data portal.^[1]