Climate Data Record for High-Resolution Global Precipitation
The second set of the CDR precipitation product is the gauge-OLR blended (GOB) analysis of global daily precipitation. First, estimates of instantaneous precipitation rates are derived from the CDR HIRS OLR data from all available satellites. The relationship between the precipitation and the OLR is established as a function of OLR intensity, location and season through PDF matching using CMORPH and HIRS OLR data for 1998 to 2013. Estimates of daily precipitation are then computed as the arithmetic mean of those from all orbits. The OLR-based precipitation estimates are then combined with the CPC unified daily gauge analysis through the optimal interpolation (OI) technique. The OLR-based precipitation estimates are used as the first guess and the gauge analysis is used as the observations to refine the first guess. A test version of the gauge-OLR blended analysis has been produced for a 35-year period from 1979 to 2013.
As a first step of the CDR project, scripts and codes of the two processing systems are being modified to fit the requirements of CDR program. Once the modifications are completed, the systems will be transferred to NCDC for real-time processing. At the AMS meetings, details of the two systems and uptodate progress will be reported.