江苏省夏季梅雨和台风型短时强降水雨滴谱特征差异分析  

Difference analysis of raindrop size distribution characteristics in Meiyu and typhoon types of short-term heavy rainfall in summer in Jiangsu Province

作　　者：李熠 郑媛媛 陈刚[1,2] 李力 徐芬 LI Yi;ZHENG Yuanyuan;CHEN Gang;LI Li;XU Fen(Nanjing Joint Institute for Atmospheric Sciences,Nanjing 210041,China;Key Laboratory of Transportation Meteorology of China Meteorological Administration,Nanjing 210041,China;Nanjing Meteorological Bureau,Nanjing 210019,China)

机构地区：[1]南京气象科技创新研究院,江苏南京210041 [2]中国气象局交通气象重点开放实验室,江苏南京210041 [3]南京市气象局,江苏南京210019

出　　处：《大气科学学报》2024年第5期798-808,共11页Transactions of Atmospheric Sciences

基　　金：国家重点研发计划项目(2022YFC3003904);中国气象局揭榜挂帅项目(CMAJBGS202211);中国气象科学研究院基本科研业务费专项资金项目(2021Z003);南京气象科技创新研究院科技发展基金项目(KJFZ202302)。

摘　　要：利用2019—2020年夏季的江苏省自动站和雨滴谱站网观测资料,从不同天气类型(梅雨和台风)和级别(20~50和>50 mm·h^(-1))将短时强降水区分为梅雨20、梅雨50、台风20以及台风50四种类型,对比分析了其雨滴谱(DSD,raindrop size distribution)特征之间的差异。统计结果表明:梅雨型强降水的雨滴平均粒径(数浓度)明显高于(低于)台风型强降水。台风型强降水的小雨滴(粒径≤2 mm)对降水的贡献率明显高于梅雨型。此外,随着降水强度的增加,梅雨50相对梅雨20的大雨滴数浓度有明显增长,雨滴平均粒径明显增大;台风50相对台风20的雨滴数浓度明显增加,粒径增长不明显。因此,台风不同级别强降水均主要由高浓度的小粒径雨滴贡献,而梅雨极端强降水则由更多大雨滴贡献,DSD特征更为复杂。选取的典型个例也观测到类似的结果,表明梅雨型强降水的雨滴谱变化相对台风型更为明显。Accurate understanding of microphysical characteristics of short-term heavy rainfall is crucial to improve the monitoring and warning capabilities of severe convective weather such as short-term heavy rainfall and accurate understanding of raindrop size distribution(DSD)characteristics of short-term heavy rainfall is also the key to improve the forecasting and early warning capabilities of it.Currently there are still few studies on DSD statistical characteristics of short-term heavy rainfall.Most studies either focus on the rainstrom process under the influence of a certain weather system or contrastive studies on different weather types.Studies on the DSD characteristics of short-term heavy rainfall under the influence of different weather systems are rare.Furthermore,most of the research is based on the observations of a single station or several stations,so the results have some limitations due to the local site observations.In this paper,based on automatic weather station data and disdrometer data during 2019—2020 in summer in Jiangsu Province,the short-term heavy rainfall is divided into four types:Meiyu 20,Meiyu 50,Typhoon 20 and Typhoon 50 according to different weather types(Meiyu and typhoon)and different rainfall intensities(20—50 and>50 mm·h^(-1)).The different DSD characteristics in different types of short-term heavy rainfall with different intensity is further analyzed to deepen the understanding of the differences of microphysical characteristics of the different types of short-term heavy rainfall.Statistical results show that the average raindrop particle size(number concentration)of Meiyu-type short-term heavy rainfall(SHR)is obviously higher(lower)than that of typhoon-type SHR on the whole.The contribution of small raindrops(diameter≤2 mm)to typhoon-type SHR is significantly more than that to Meiyu-type SHR.Furthermore,with the increase of rainfall intensity,the large raindrop number concentration and the average raindrop particle size of Meiyu-type SHR with intensity over 50 mm·h^(-1)

关 键 词：短时强降水 雨滴谱 梅雨 台风 江苏 

分 类 号：P426.6[天文地球—大气科学及气象学]