Monitoring Sea Surface Salinity in the Global Ocean from Ships of Opportunity
Sea Surface Salinity (SSS) is one of the fundamental variables for which global sustained observations are needed in CLIVAR, the international program on CLImate VARiability and predictability, and GOOS, the Global Ocean Observing System sponsored by the IOC, WMO, UNEP, and ICSU.
SSS measurements are needed to improve our knowledge of the earth’s water cycle and climate. SSS has proven to be valuable for improving estimates of evaporation minus precipitation (E-P) budgets, describing and understanding climate variability at seasonal to decadal time scales, testing physical processes, assessing numerical model skills, quantifying the role of salinity on sea level change, improving El Nino prediction lead time, quantifying the ocean-atmosphere CO2 exchanges, and so on.
The importance of SSS in the climate system has motivated the development by European and USA/Argentina space agencies of dedicated satellite missions (SMOS, Aquarius and SMAP) to enhance global observations.
Recognizing the importance of SSS for climate research and operational oceanography (see MERCATOR and GODAE), the present SSS Observation Service aims at collecting, validating, archiving and distributing in situ SSS measurements derived from Voluntary Observing Ship programs. It is based on the IRD historical savoir-faire, and presently federates the efforts of scientists from – and/or benefits from financial supports of – different French institutes (IRD, CNES, CNRS, IFREMER, INSU, IPEV, OMP).
This SSS Observation Service has an “Observatoire de Recherche en Environnement” (ORE) label. It also represents the French contribution to the international Global Ocean Surface Underway Data (GOSUD) program.