ESA's Soil Moisture and Ocean Salinity (SMOS) satellite was launched on November 2nd, 2009 from Northern Russia. The SMOS single payload consists of a synthetic aperture radiometer operating at L-band (1.4 GHz). Once the commissioning phase was over, SMOS global calibrated brightness temperatures of the sea surface are now available. This paper presents a preliminary work to improve the definition of the Geophysical Model Function (GMF), which relates the sea emissivity on L-band with sea surface salinity (SSS) and other geophysical parameters. The GMF is a crucial ingredient in salinity retrieval, as it is used in the SMOS operational processor at DPGS. The GMF definition should be as simple (i.e., avoiding parameter cross-correlations) and efficient (i.e., representing the best fit of the measurements) as possible. Nevertheless, non-linear dependencies and wind direction effects need to be thoroughly examined in order to produce a quality product. In this paper, we will set the grounds for the future development of a fully empirical GMF, and we discuss the methodological issues to be considered in such a development

The SMOS-BEC is a joint initiative of CSIC and UPC mainly funded by the Spanish Ministry of Education and Science through the National Program on Space. We also acknowledge financial support from MIDAS-5 project (ESP2007-65667-C04-01)

ESA Living Planet Symposium 28 June – 2 July 2010 Bergen, Norway

Peer Reviewed