Rain microphysical properties based on radar observation in Korea

As rain microphysical properties can vary with geographical change, analysis of rain drop shape distribution for local area is important to a radar based quantitative precipitation estimation. In this paper, we analyze rain microphysical properties comparing with KICT radar observation and theoretically simulated data. The KICT X-band dual-polarization radar is installed (Latitude: 37.6688, Longitude: 126.7389) close to Seoul metropolitan area to carry out especially urban precipitation study. In order to get the rain microphysical information in Korea, we investigated the scatter plots of Z_dr versus Z, K_dp versus Z, as well as K_dp/Z versus Z_dr. In addition, the theoretical relations between these dual-polarization parameters are also generated by simulation. In the simulation, a gamma DSD model is assumed with the ranges as 0.5≤D_o≤3.5 mm, 3≤log1₀N_w≤5, and -1≤m≤5 for the parameters and with the additional constraint that R <; 300 mm/hr. The parameters D₀, log₁₀N_w, and μ are varying uniformly over their respective ranges to form a large table of D₀, N_w, and μ. Scattering calculations are performed at 9.4 GHz (X-band) for Z, Z_dr, and K_dp.