Global monthly rainfall estimates and other hydrological products have been produced from 1987 to present using measurements from the Defense Meteorological Satellite Program (DMSP) series of Special Sensor Microwave Imager (SSM/I). The aim of this paper has two purposes: to present the recent efforts to improve the quality control (QC) of historical antenna temperature of SSM/I sensor since 1987 to 2008 and how this improvement impacts the different hydrological products that are generated at NOAA/NESDIS.

Beginning in 2005, the DMSP Special Sensor Microwave Imager/Sounder (SSMI/S) has been successfully operating on the F16, F17 and F18 satellites. The second objective of this paper is focused on the application of SSMI/S channels to evaluate the performance of several hydrological products using the heritage of existing SSM/I algorithms and to develop an improved strategy to extend the SSM/I time series into the SSMIS era, starting with data in 2009. The continuity of hydrological products from SSM/I to SSMI/S has shown to be a valuable contribution for the precipitation and climate monitoring community but several sensor issues must be accounted for to meet this objective.