GPM-DPR observed microphysical characteristics of the Arabian Sea tropical cyclone

The precipitation characteristics of tropical cyclones (TCs) formed between 2014-2021 over the Arabian Sea during the onset phase of monsoon and after the monsoon (post-monsoon) seasons have been investigated through the space-borne dual-frequency precipitation radar of the Global Precipitation Measurement (GPM-DPR) satellite level 2, V07 observation. In a cloud that is producing precipitation, the two-dimensional frequency distribution of the liquid water content (LWC; g/m2) and non-liquid water content (IWC; g/m2) exhibits a clear seasonal and cloud-type dependence. For the precipitating cloud of stratiform origin of TCs in the monsoon and post-monsoon seasons, a significant part of rain droplets is present in the LWC limit of 0-800 g/m2 and the IWC limit of 0-350 g/m2. In contrast to the stratiform precipitation associated with the TCs, the LWC quantity is additionally more, and IWC is less for the convective origin precipitating cloud. In the monsoon and post-monsoon season, the mean values of the mass-weighted mean diameter, Dm (mm), are 1.29 (1.47) mm and 1.27 (1.31) mm, respectively, for the stratiform (convective) cyclonic cloud. It is noticed that when the value of Dm increases, the normalised intercept parameters (Nw) decrease, regardless of the season and cloud type related to the TCs. While stratiform precipitation contains a considerably high concentration of smaller-sized rain droplets during both seasons, the number concentration of bigger rain droplets is significantly high during convective precipitation. From the contoured frequency with altitude diagram (CFAD) plots for Dm and Ze for the cyclonic cloud in both seasons, we observe a large concentration of ice and supercooled liquid particles available above the melting layer and a significant concentration of rain droplets in liquid state present below the melting layer. We derived the contribution of the different microphysical processes (break-up, size-sorting, collision-coalescence, and evaporation processes) in the rain droplets formation below the melting layer. It is found that the process of collision-coalescence is predominating microphysical process for convective precipitation. The break-up process is a primary microphysical process in the precipitating cloud of stratiform origin.