Study on the relationship between cloud height and precipitation parameters in tropical and subtropical regions based on CloudSat CPR and GPM DPR measurements

Based on the spatial and temporal matching data of Cloud Profile Radar(CPR)carried by CloudSat and Dual-frequency Precipitation Radar(DPR)on the Global Precipitation Measurement(GPM)satellite from 2014—2017, we examine the relationships among cloud top height(CTH), cloud base height(CBH), and precipitation layer thickness(△h), and their associations with surface precipitation intensity and microphysical properties of precipitation, across four types of precipitation systems—marine stratiform, marine convective, terrestrial stratiform, and terrestrial convective—in tropical and subtropical regions. The results reveal a strong positive correlation between CBH and surface precipitation rate for all four precipitation types, with correlation coefficients exceeding 0.55, surpassing the correlation between CTH and surface precipitation rate. An analysis of the mean precipitation layer thickness(△h)across different precipitation rate intervals reveals that, for all four precipitation types, the average △h tends to decrease as the precipitation rate increases. By analyzing the relative contributions of evaporation and warm rain processes during the descent of precipitation particles to the surface in different CTH intervals, it can be concluded that as the cloud top height increases, the complex interactions and variability of various microphysical processes such as evaporation and warm rain during the descent of raindrops lead to a weakened correlation between surface precipitation intensity and CTH. The statistical analysis of the relationship between CBH and surface precipitation drop size distribution parameters reveals that, with increasing CBH, the effective droplet radius (Dm) shows a significant increasing trend across all four precipitation types, whereas the droplet concentration parameter (dBNW) exhibits distinct variations depending on the precipitation type. In marine stratiform precipitation, the increase in both Dm and Dm suggests their joint contribution to surface precipitation enhancement. Conversely, the significant reduction in dBNW in terrestrial convective precipitation indicates that surface precipitation enhancement is primarily driven by larger droplets. This difference reflects that the relationship between CBH and the microphysical characteristics of surface precipitation varies significantly across different precipitation types.