Combined Ku and Ka band observations of precipitation and retrievals for GPM Ground validation

The dual-frequency precipitation radar (DPR) aboard the GPM (Global Precipitation Measurement) core satellite is expected to improve our knowledge of precipitation processes. Ground validation is an integral part of all satellite precipitation missions which helps provide insight into the physical basis of the retrieval algorithm. A dual-frequency (Ku and Ka band) and dual-polarization ground radar will be built in near future to perform cross validation with GPM. This paper presents a new algorithm to retrieve parameters of the drop size distribution from this dual-frequency and dual-polarization ground. The method is based on combination of DFR (dual frequency ratio) and dual-polarization approach. Attenuation correction is solved within the retrieval process. The proposed algorithm is evaluated based on simulated Ku and Ka band realistic observations, for rain, melting layer and ice parts.