Testing a technique for retrieving the rain drop size distribution moments from X-Band polarimetric radar data during a warm rain event

A method for retrieving the moments of rain drop size distributions (DSDs) from X-band polarimetric radars is tested using data from a warm rain event which occurred near Incheon, Republic of Korea. The method involves the use of attenuation-corrected radar reflectivity for horizontal polarization, attenuation-corrected differential reflectivity, and specific attenuation for horizontal polarization. The method had been previously tested for an event in Greeley, Colorado, USA, and had resulted in very encouraging results. In this paper, we apply the same method to an isolated warm rain cell which occurred during the summer season of 2020 in Incheon. The height profiles of the retrieved moments were examined. We showed that the application of our retrieval method results in very plausible results in terms of the dominant microphysical processes associated with warm rain events. We also included a convergence region where the drop break-up process is clearly highlighted as being the dominant process. With such encouraging results, our future plan will be to increase the accuracy of the retrieval method by reducing the parameterization errors, for example, by using finely tuned shape parameters to represent the underlying function of the DSDs for warm rain events. The tuning will entail accurate measurements of the full DSD spectra in Incheon.