Presented at the 2014 Ocean Salinity Science and Salinity Remote Sensing WorkshopThe subtropical oceans all display relatively salty surface water, forming a regional sea surface salinity maximum (SSS-max), a response to the global hydrological cycle. Regional differences in basin SSS-max intensity and patterns complicate a direct comparison. We apply a methodology to compare the SSS-max regimes between oceans using a reference salinity based on the MIMOC climatology, eliminating the uncertainty due to an arbitrarily chosen isohaline for each ocean. Using the anomaly from the reference salinity reveals marked differences in patterns and location within each ocean subtropical regime, a response to ocean geometry and associated ocean processes. The Aquarius/SMOS satellite missions provide seas surface salinity monitoring with a far better, near synoptic, coverage compared to other observational methods. Thus enabling the community to use the SSS-max as an indicator of change in the hydrological cycle in combination with ocean processes. The average location and shape of the SSS-max in each basin vary significantly. Aquarius captures the SSS-max characteristics, permitting quantification of interannual variability in the subtropical regions. The seasonal cycle (timing and amplitude) of all basins except the South Pacific is captured, introducing an interesting question whether this behavior is due to the Aquarius retrieval error or caused by different dynamics in the South Pacific. For further details see: Gordon, Giulivi, Busecke, Bingham, submitted to the SPURS Oceanography special issue.