【摘要】 四川复杂地形容易触发对流，暴雨发生频次较高，研究该地区暴雨结构及宏微观物理特征有重要意义和价值。本文利用GPM卫星资料分析了2018年5月21日四川一次特大暴雨的三维结构及宏微观特征。结果表明：此次特大暴雨过程由一个α中尺度对流系统造成；层状云降水与对流云降水的样本比例为2.5:1，但对流云降水率为层状云降水率的5倍；环境风场垂直切变较强导致最大雨水含量的位置与最大云冰含量的位置不一致；对流云降水反射率因子高频区数值随高度变化比层状云降水显著；粒子数浓度参数和有效粒子半径的频率分布反映出在4～7 km高度对流云中雨滴碰并增长过程显著，4 km以下雨滴蒸发和破碎过程明显，层状云降水粒子数浓度参数和粒子有效半径的范围比对流云窄且随高度变化不明显。更多还原

【Abstract】 Due to the complex terrain in Sichuan, it is easy to trigger convection, and the frequency of heavy rain is high. It is very important to study the macro and micro physical characteristics of heavy rain in Sichuan. The GPM data is used to study the structural characteristics of the heavy rainstorm in Sichuan region on 21 May 2018. The results show that the heavy rainstorm was caused by an meso-α-scale convective system. The sample ratio of stratiform cloud precipitation to convective cloud precipitation was 2.5:1, convective cloud precipitation rate was 5 times that of stratiform cloud precipitation. The strong vertical shear of the ambient wind field led to the difference between the location of the maximum rain water content and the location of the maximum cloud ice content. The value of high frequency of reflectivity factor for convective cloud precipitation varied significantly with height than that of stratiform cloud precipitation.The particle number concentration parameter and the effective particle radius reflected that the process of coalescence growth of droplets was remarkable in convective cloud in the range of 4～7 km, and the process of evaporation and fragmentation of raindrop below 4 km was significant. The ranges of particle number concentration parameters and particle effective radius in stratiform clouds were narrower than those of convective clouds, and the changes with height were not obvious.更多还原