Statistical Characteristics of Raindrop-Size Distribution in the Summer Season Observed in the South China Sea

Precipitation is one of the most important resources for human activity and global distribution of precipitation amount. What’s more, its variation is essential for global water cycle. The South China Sea (hereinafter referred to as SCS) is the largest and the southernmost sea in China. Additionally, a large of amount of water vapor transported by monsoon from SCS is a main source of the precipitation over coastal areas in southern China during summer monsoon season, and may cause uneven distribution of rainfall amount along coastal areas in southern China. Deep insight into the raindrop size distribution (DSD) and its variability are essential for understanding precipitation microphysics since DSD contains abundant information about precipitation microphysics. In this study, the DSD over SCS in summer monsoon seasons were investigated with observations collected by the second-generation Particle Size and Velocity (Parsivel²) distrometer fixed on a scientific investigation ship over the South China Sea from June of 2019. Statistical analysis of DSD is used to feature the characteristics of DSD of SCS in June. A three-parameter gamma distribution is used to describe the measured raindrop spectra. Finally, a new Z-R relationship which localized in SCS is proposed to provide useful information for the precipitation retrievals based on weather radar observations.