Validation of raino-rain threshold value of cloud liquid water for microwave precipitation retrieval algorithm using CloudSat precipitation product

摘要

The raino-rain threshold value of cloud liquid water (CLW) is important for the microwave precipitation retrieval algorithms. In our previous study, we proposed a parameterization of raino-rain threshold value of CLW as a function of storm height for Global Satellite Mapping of Precipitation (GSMaP) algorithm. In this study, we determine raino-rain threshold value of CLW using CloudSat precipitation product and the cloud liquid water derived from Aqua/AMSR-E. The threshold values of CLW from CloudSat precipitation product are lower than 0.5 kg m~(-2) for GSMaP over all regions. The threshold value of CLW is found at its peak in the Tropics and decreases poleward. The threshold value of cloud liquid water contents computed from threshold value of CLW divided by the zonal mean storm height from PR3A25 is employed on the parameterization of threshold value of CLW. The result shows that GSMaP with new parameterization can detect the shallow rain observed by CloudSat.