滇中地区不同影响系统下3次短时强降水过程的大气环境特征和雷达特征分析  

Analysis of Atmospheric Environment Characteristics and Radar Characteristics of Three Short-time Heavy Precipitation Cases under Different Influence Systems in Central Yunnan

作　　者：周泓 闵颖[2] 许彦艳[2] 纳丽佳 业红伟 ZHOU Hong;MIN Ying;XU Yanyan;NA Lijia;YE Hongwei(Yunnan of Yuxi Meteorological Bureau,Yuxi 653100,Yunnan,China;Yunnan Meteorological Observatory,Kunming 653100,Yunnan,China;Yunnan of Puer Meteorological Bureau,Puer 665000,Yunnan,China)

机构地区：[1]云南省玉溪市气象局,云南玉溪653100 [2]云南省气象局气象台,云南昆明650034 [3]云南省普洱市气象局,云南普洱665000

出　　处：《高原气象》2024年第1期166-183,共18页Plateau Meteorology

基　　金：云南省重点研发计划-社会发展专项(202203AC100005);云南省气象局创新团队项目(2022CX07)。

摘　　要：利用常规观测资料、NCEP 1°×1°再分析资料、逐时和逐5 min自动站降水资料以及昆明CINRAD/CC多普勒雷达资料,针对滇中地区2021年主汛期不同影响系统下的3次短时强降水过程,对比分析了降水特征、环流形势、大气环境特征以及雷达回波的结构、形状、演变的基本特征。结果表明:3次短时强降水过程影响系统差异主要在于500 hPa天气系统不同,700 hPa都有切变线影响,但是形成原因各异,地面均有辐合线或弱冷锋配合。3次过程的环境条件在不稳定层结、近地层水汽、垂直风切变方面与中国其他地区短时强降水发生的环境条件具有一致性,但是在大气整层可降水量、对流有效位能、SWEAT指数等方面存在明显差异。对流回波的形状有点状回波、块状回波、带状回波、絮状回波等。对流风暴分为高质心型、低质心型以及混合型;短时强降水有单独出现某种对流风暴类型的阶段,也有多种对流风暴类型同时出现的阶段;CAPE值和SWEAT指数与对流风暴类型具有一定的相关关系。强回波剖面呈柱状结构或者塔状结构,35 dBz强回波接地,而没有悬垂特征。短时强降水多产生于长时间停滞型或移动缓慢型的对流回波,还有部分短时强降水产生于“列车效应”中。短生命周期的单体生消形成的短时强降水持续时间绝大部分在1 h以内,但是单体合并组织和反复生消或者“列车效应”形成的短时强降水持续时间常在1~3 h。高质心型对流风暴产生的瞬时雨强可达10 mm·(5min)-1以上,低质心型和混合型对流风暴可产生的雨强范围较大,大多在3~10 mm·(5min)-1,少数也可达到10 mm·(5min)-1以上。Based on conventional observation data,NCEP 1°×1°reanalysis data,hourly and 5min automatic station precipitation data,and CINRAD/CC Doppler radar data in Kunming,three short-time heavy precipitation cases under different influence systems during the main flood season of 2021 in central Yunnan are studied.The characteristics of precipitation,circulation pattern,atmospheric environment and structure,shape and evolution of radar echoes are compared and analyzed.The results show that the difference of the three short-time heavy precipitation cases is mainly due to the difference weather systems on 500 hPa.There are shear lines at 700 hPa,but the formation seasons are different.There are convergence lines or weak cold fronts on the ground.The environmental conditions of the three cases are consistent with those of other regions of China in terms of unstable stratification,water vapor near the ground and vertical wind shear,however,there are significant differences in the total precipitable water,CAPE,SWEAT index.The shape of convective echo includes dot echo,block echo,strip echo,flocculent echo and so on.Convective storm type can be divided into high-echo-centriod convective storm,low-echo-centriod convective storm and mixed-echo-centriod convective storm.Short-time heavy precipitation has a single stage of some convective storm type,also has several convective storm types appearing at the same time.CAPE and SWEAT index have a certain correlation with convective storm types.Strong echo profile is columnar structure or tower structure.35 dBz strong echo is grounded without overhang characteristics.Short-time heavy precipitation is mostly generated by long-time stagnant or slow-moving convective echo,some short-time heavy precipitation is also generated in the"train effect"of radar echoes.The duration of short-term heavy precipitation formed by monomer with short life cycle is mostly within 1h,but the duration of short-term heavy precipitation formed by monomer combination and repeated generation and extinction or"t

关 键 词：短时强降水 环流形势 大气环境条件 雷达回波特征 

分 类 号：P468[天文地球—大气科学及气象学]