Ocean salinity from satellite-derived temperature in the Antarctic Ocean

The aim of the MINERVE project (Mesures a l'INterface Eau-aiR de la Variabilite des Echanges de CO2) is to observe and understand the seasonal and interannual variability of the partial pressure of CO2 (pCO(2)) in surface waters using hydrological and biogeochemical data in the Southern Ocean south of Australia. Logistics routes of the RV Astrolabe provide access to scarcely studied areas, thus allowing us to understand the different processes acting in this area of the Antarctic Ocean. The surface area covered by these cruises, however, is tiny compared with the total surface area of the Antarctic Ocean. Correlations between in situ surface temperature and salinity data were applied to satellite images of sea surface temperature to map ocean surface salinity over a much wider area than under the cruise tracks. Comparisons with salinity data from satellites which provide similar to 100 km resolution and 0.1 accuracy indicate that we are able to map salinity at 4 km resolution and almost the same accuracy of +/- 0.1.