Applying high resolution spacebased measurements from microwave radiometers and scatterometers, surface fresh water flux and divergence of moisture transport are derived over the oceans. Sea surface salinity data in the tropical Pacific are available from volunteer ship reports at very coarse resolution. Salinity advection is computed using ocean currents estimated from satellite observed sea level and surface wind vectors. A tentative view of the seasonal and interannual variations in the tropical Pacific hydrological budget will be presented. Different products of satellite based precipitation and evaporation are also compared.