山西晋城“7·11”暴雨过程雨滴谱特征  

Raindrop Size Distribution Characteristics of“7·11”Rainstorm in Jincheng,Shanxi

作　　者：葛黎黎 吕国真 赵桂香[3] 李亚军[1] 郭栋 GE Lili;LYU Guozhen;ZHAO Guixiang;LI Yajun;GUO Dong(Shanxi Meteorological Information Center,Taiyuan 030006,China;Shanxi Meteorological Service Center,Taiyuan 030002,China;Shanxi Meteorological Observatory,Taiyuan 030006,China)

机构地区：[1]山西省气象信息中心,山西太原030006 [2]山西省气象服务中心,山西太原030002 [3]山西省气象台,山西太原030006

出　　处：《沙漠与绿洲气象》2023年第3期17-25,共9页Desert and Oasis Meteorology

基　　金：国家自然科学基金项目(41475050)。

摘　　要：利用降水现象仪观测资料,对2021年7月11日山西晋城一次暴雨过程的雨滴谱特征进行分析。结果表明:雨滴数浓度、雨强和谱宽随时间变化趋势基本一致;雨滴直径等级频数百分率和质量百分率分布均呈明显的双峰或三峰结构;此次过程以直径D<1 mm的小雨滴为主,其对雨强R的贡献率仅为7.46%,而1 mm≤D<3 mm的大雨滴对R的贡献率达到了77.44%;雨滴落速主要集中在2~5 m/s。当R≥20 mm/h时,Gamma分布参数N0、μ和λ随时间的起伏变化相对平缓,平均变化率分别为6.2%、46.7%和18.0%;lg N_(W)-D_(m)分布显示,此次低涡暴雨过程既非大陆性对流降水,亦非海洋性对流降水;μ-λ之间存在较好的二项式函数关系,相关系数为0.901。幂函数对于降水动能参数关系Et-R和Ed-R的拟合性能更优,二项式函数拟合对于Ed-Dm效果更好。采用最小二乘法得到Z-R拟合关系,在R≥20 mm/h时,估测效果优于经典Z-R关系。Based on the observation data of precipitation phenomenometer,the raindrop size distribution(DSD)characteristics of a rainstorm on July 11,2021 in Jincheng,Shanxi were analyzed.The results show that the variation trends of number concentration,rainfall intensity and the maximum diameter with time were generally consistent.The frequency percentage patterns and the quality percentage patterns of different raindrop diameter classes presented obvious bimodal or trimodal structure.The small raindrops with diameter less than 1.0 mm were the main raindrops of the rainstorm process but contributed only 7.46%to rainfall intensity,while large raindrops with diameter of 1.0~3.0 mm contributed 77.44%to rainfall intensity.The falling velocity was mainly concentrated in the range of 2~5 m/s.N_0,μandλof Gamma distribution changed gently with time when rainfall intensity was greater than 20 mm/h,the average rates of change were 6.2%,46.7%and 18.0%.lg N_W-D_(m)distribution showed that the low-vortex rainstorm was neither continental convection nor maritime convection.There was a good binomial relation betweenμandλ,the correction coefficient was 0.901.The power function had better fitting performance for E_t-R and E_d-R of precipitation kinetic energy,and the binomial function worked better for E_d-D_m.The least square method was used to obtain the Z-R fitting relationship,and the estimation effect was better than that of the classical Z-R relationship when R≥20 mm/h.

关 键 词：雨滴谱 GAMMA分布 低涡暴雨 降水动能 Z-R关系 

分 类 号：P426.6[天文地球—大气科学及气象学]