Our AMSR-E' SSS retrieving methodolgy is expanded here to revisit the SSS observed in the tropical Atlantic Ocean with a multi-year time series covering 2003-2008 of remote sensing and concurrent in situ observations. AMSR-E data, analysed SST and ocean color products, as well as in situ SSS data, were thus collected within the suffciently warm latitudinal band between 10°S and 20°N, including several major large-scale freshwater pools (Amazon, Orinoco and Congo plumes, Gulf of Guinea).
An empirical algorithm to retrieve SSS based on satellite and in situ data climatological relationships is now applied to generate monthly and 10-days averaged SSS charts at a spatial resolution of 0.25°. This first synoptic-scale 'satellite SSS' product is validated through comparison with independent and coincident in situ data acquired throughout the period from a variety of sources. While less accurate than in situ SSS observing systems, the spatio-temporal variability of the freshwater pool signatures seen in these enhanced-resolution new satellite SSS products is shown to be very consistent with the one observed in situ SSS, climatological surface currents, ocean color parameters, satellite rain rate, and in situ river discharge data.
Such measurements shall therefore certainly help better monitoring major freshwater pool characteristics at the surface
of the Tropical Atlantic, which is essential particularly with regard to oceanic circulation modeling,
ecology, biogeochemistry and bio-optics.
Examples of Monthly climatologies of AMSR-E brightness temperature differences (Kelvins) and retrieved SSS from AMSR-E data grouped in 0.25◦ square bins in latitude x longitude. Includes data for the months of January & August acquired during the periood 2003-2008.