The ESA mission SMOS was planned with the aim of obtaining more precise data concerning the global water cycle. The exchange of water between land, ocean and atmosphere is one of the principal factors influencing weather and climate patterns. Constituents of the global hydrological cycle that can be measured with SMOS are a) the soil moisture, b) the ocean surface salinity, and c) the thin (< 50 cm) sea ice thickness.
SMOS is a polar orbiting satellite based passive microwave sensor operating at L-Band (1.4 GHz). The brightness temperature measured by SMOS at L-Band is dependent on the SST and SSS of the seawater as well as on the sea surface roughness induced by wind and waves. The surface salinity is derived by inverse models on a global basis, taking auxiliary information about the SST and the sea surface roughness into account.
This new (Version 4) data set of the SMOS sea surface salinity produced by the University of Hamburg contains estimates of the theoretical retrieval error and a bias corrected salinity at a finer grid resolution of 0.5 x 0.5 degrees. The bias is obtained from a comparison of the SMOS data with in situ salinity data (EN4.2), comprising mostly ARGO float observations. The data set includes the uncorrected and gridded as well as the bias-corrected version of the SMOS sea surface salinity.
Last update of the data set: May 18, 2017.