利用山东济南章丘站L波段探空秒数据和激光雨滴谱仪资料,对2015年3月31日—4月2日山东一次受低槽冷锋、切变线和江淮气旋共同影响而造成的大范围春季转折性降水天气过程的云系垂直结构演变以及不同天气系统下降水云微物理特征进行对比分析.结果表明:(1)降水前期,云系表现为"上层云—干层—下层云"2层云结构;随后降水持续期,逐渐演变为中、低云垂直发展旺盛的云系;降水末期,云顶高度下降,云体再次分离成较弱的2层云结构,中间有深厚的干层时,降水结束;(2)低槽冷锋降水雨滴谱最窄,江淮气旋降水雨滴谱最宽;(3)降水强度与雨滴谱各特征参量均具有较好的正相关性,但不同天气系统影响下其相关性有差异;(4)雨滴落速主要集中在2~4 m·s-1之间,这与雨滴下落末速度理论值基本相符.%Being subjected to the low trough with cold front,shear line and Changjiang-Huaihe cyclone,a wide-range turning pre-cipitation occurred in Shandong Province from March 31 to April 2,2015.Based on the sounding data from L-band radiosonde radar and raindrop spectrum from Thies laser raindrop spectrometer in Zhangqiu of Shandong Province,the cloud vertical structure and micro-physical properties of the turning precipitation under different weather system conditions were comparatively analyzed.The results are as follows:(1 )At the beginning of the precipitation,the vertical structure of cloud was manifested as two layers with 'upper layer cloud-dry layer-lower layer cloud'.Subsequently,the cloud in the vertical direction fully developed into the medium and low clouds with continuous rainfall.At the end of the precipitation,the height of cloud top decreased,and the cloud once again separated into weaker two layers,when the dry layer was deeper,the rainfall completely ended.(2)The distribution of raindrop size for the low trough with cold front precipitation was the narrowest,and that for the Changjiang-Huaihe cyclone precipitation was the widest.(3)The precipi-tation intensity was positive related with feature parameters of raindrop,but the correlation was different under different weather system conditions.(4)The terminal velocity mainly concentrated in 2-4 m·s-1 ,which was basically consistent with theoretical value.
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