Passive microwave observation spatial biases and uncertainty induced by sea-surface salinity

Using in situ sea-surface salinity (SSS) climatology for passive microwave ocean surface emissivity calculations introduces biases resulting from climatology observations that are very sparse in space and time. Newly available satellite SSS measurements provide the means to examine the significance and global distribution of these biases, as well as the significance of data uncertainty to passive microwave retrievals. This study explores the biases and uncertainty of Level-3 SSS data from the Soil Moisture-Ocean Salinity (SMOS) Barcelona Expert Centre (BEC) with respect to climatology and relates them to passive microwave significance in terms of surface brightness temperature.