A Group for High Resolution Sea Surface Temperature (GHRSST) gap-free (L4) Sea Surface Temperature (SST) analysis produced daily on an operational basis by the Danish Meteorological Institute (DMI) using an optimal interpolation (OI) approach on a global 0.05 degree grid. Whereas along swath observation data essentially represent the skin or sub-skin SST, the L4 SST product is defined to represent the foundation (SSTfnd). SSTfnd is defined within GHRSST as the temperature at the base of the diurnal thermocline. It is so named because it represents the foundation temperature on which the diurnal thermocline develops during the day. SSTfnd changes only gradually along with the upper layer of the ocean, and by definition it is independent of skin SST fluctuations due to wind- and radiation-dependent diurnal stratification or skin layer response. SSTfnd corresponds to the temperature of the upper mixed layer which is the part of the ocean represented by the top-most layer of grid cells in most numerical ocean models. It is never observed directly by satellites, but it comes closest to being detected by infrared and microwave radiometers during the night, when the previous day's diurnal stratification can be assumed to have decayed. The processing combines night-time GHRSST L2P skin and subskin SST observations from several satellites. The data is inter-calibrated and bias corrected before being merged and interpolated using an optimal interpolation scheme to provide daily gap-free fields. The optimal interpolation scheme uses the previous days analysis as a background field. An ice field from the EUMETSAT OSI-SAF is used to mask out areas with ice.

The Sentinel-6 Level-2P skewness products was developed to estimate the skewness from Sentinel-6 LR (Low Resolution Mode) and HR (High Resolution Mode) acquisitions. That demonstration product is generated by different retracking processes, provides an initial estimation of such a phenomenon and allows a finer description of the sea state.

The SWOT L3_LR_SSH product provides ocean topography measurements obtained from the SWOT KaRIn and nadir altimeter instruments, merged into a single variable. The dataset includes measurements from KaRIn swaths on both sides of the image, while the measurements from the nadir altimeter are located in the central columns. In the areas between the nadir track and the two KaRIn swaths, as well as on the outer edges of each swath (restricted to cross-track distances ranging from 10 to 60 km), default values are expected. SWOT L3_LR_SSH is a cross-calibrated product from multiple missions that contains only the ocean topography content necessary for thematic research (e.g., oceanography, geodesy) and related applications. This product is designed to be simple and ready-to-use, and can be combined with other altimetry missions. The SWOT L3_LR_SSH product is a research-orientated extension of the L2_LR_SSH product, distributed by the SWOT project (NASA/JPL and CNES). SWOT L3_LR_SSH is managed by the SWOT Science Team project DESMOS. The "Expert" version of SWOT L3_LR_SSH (the "Basic" version is the subject of a separate metadata sheet) includes each algorithm, correction, or external model incorporated into the SWOT L3_LR_SSH product as a separate layer. In addition to the SSH anomalies, this "Expert" version also includes mean dynamic topography (as in the "Basic" version), backscatter coefficient (sigma0), mean sea surface and geostrophic currents (absolute and anomalies).

This product contains average 10 days & monthly salinity field based on L2P products, ascending and descending orbits being processed separately. ** This product is no longer available, see below **

This product contains average 10 days & monthly salinity field corrected from land-sea contamination and latitudinal bias, based on L2Q products, ascending and descending orbits being processed separately. ** This product is no longer available, see below **