Our effort to examine the role of precipitation on global water cycle will continue. Using the moisture transport and evaporation over tropical and subtropical oceans derived from TRMM and QuikSCAT observations, we will characterize the spatial-temporal variations of water balance in the atmosphere and salinity balance in the upper ocean. The closure of the water and salinity budget will put constraints on the uncertainty of precipitation measurements and be used to validate other spacebased hydrologic parameters. Regional discrepancies identified will be used to improve the retrieval algorithm of moisture transport and evaporation. This water budget study will be extended to high-latitude ocean, using SSM/I and AMSR-E data, and to land (light rain regions of Sahel), from synoptic to interannual time scales. They will not only expand the characterization of global water cycle, but will bolster the credibility of spacebased measurements, paving the way for the Global Precipitation Mission. The data produced will be distributed through our established data system. Our proposal is relevant to two categories listed in the proposal call: 1.1 Precipitation variability and its relationship to climate diagnostics and change; and 1.3 Applications to hydrology and oceanography.
