2017年鹰潭市城区暴雨天气与回波特征分析  

Analysis of rainstorm weather and echo characteristics in Yingtan city in 2017

作　　者：桂园园 马中元[2] 齐永胜 余剑浩 张萍 GUI Yuanyuan;MA Zhongyuan;QI Yongsheng;YU Jianhao;ZHANG Ping(Meteorological Bureau of Yingtan City,Jiangxi Province,Yingtan 335000,China;Jiangxi Institute of Meteorological Science,Nanchang 330046,China)

机构地区：[1]江西省鹰潭市气象局,江西鹰潭335000 [2]江西省气象科学研究所,江西南昌330046

出　　处：《自然灾害学报》2020年第3期63-75,共13页Journal of Natural Disasters

基　　金：中国科学院战略性先导科技专项(A类-XDA19040202,41675045);国家自然科学基金面上项目(41975001,41675045);中国气象局气象关键技术集成与应用项目(CMAGJ2013M74);中国气象科学研究院开放课题(2012LASWB01);南京雷达气象与强天气开放基金项目(BJG201205);江西省气象科技项目(JXKE20180812)。

摘　　要：使用MICAPS常规天气、江西WebGIS雷达拼图、自动气象站等资料,采用天气学中尺度天气分析方法和雷达回波图像形态分析方法,对2017年5次鹰潭市城区暴雨过程进行分析,结果表明:鹰潭5次城区暴雨有2种降水类型:一是对流型降水,二是混合型降水。对流型强雨带呈东北~西南走向的带状;混合型雨带主要呈东~西或西南~东北走向。造成鹰潭暴雨的主要天气系统有地面倒槽、准静止锋、地面辐合线、地面气旋等;925hPa至500hPa常常伴有西南急流、低涡、切变线,其中850hPa都存在一个比湿的大值区;200hPa常处在高空急流区的右侧、分流区内。V-3θ图上露点假相当位温曲线、饱和假相当位温曲线呈现“一”字形横向平直分布和竖向准重合型,对流层水汽充沛且深厚,水汽极易饱和,降水效率高,十分利于产生暴雨、大暴雨天气。造成鹰潭城市暴雨的雷达回波特征主要是絮状回波带,回波单体强度虽然不强,但维持时间长,反复经过一地,单体回波呈现“列车效应”,最后形成暴雨或大暴雨天气。锋面回波带和锋前暖区的超级单体、强回波单体和短带回波,也会形成短时强降水而产生暴雨。在垂直剖面图上,对流性降水的强回波单体回波0dBz上沿达到12km以上,45dBz强回波顶高超过6km;回波中心强度达到55~60dBz,有时在强回波上方出现旁瓣造成的虚假回波。混合型降水回波的0dBz上沿在12km左右,但45dBz强回波顶高不超过6km,属于典型“低质心”降水形式。Using the data of MICAPS conventional weather,WebGIS Radar Mosaic and automatic weather station,we analyzed the rainstorm process of the five cities in 2017 by using the method of synoptic mesoscale weather analysis and radar echo image form analysis.There are two types of precipitation in the five urban rainstorms:one is convective precipitation,and the other is mixed precipitation.The convective heavy rain belt is northeast-southwest trend,while the mixed rain belt is East-West or southwest-northeast trend.The main weather systems causing torrential rain include ground reverse trough,quasi stationary front,ground convergence line,ground cyclone,and so on.925hPa to 500hPa are often accompanied by southwest jet stream,vortex and shear line,where 850hPa has a large area of specific humidity;200hPa is often located in the right side and diverging area of the upper level jet stream area.The dew point PSEUDO-EQUIVALENT potential temperature curve and saturated PSEUDO-EQUIVALENT potential temperature curve on V-3θmap show a"one"horizontal distribution and vertical quasi-coincidence type.The troposphere has abundant and deep water vapor,which is easy to saturate and has high precipitation efficiency.It is very conducive to the occurrence of rainstorms and heavy rainstorms.The radar echo characteristics of the heavy rain in the city are mainly the floc echo band.Although the intensity of the echo monomer is not strong,but the maintenance time is long,the echo of the single unit shows a"train effect",and finally a rainstorm or heavy rainstorm occurs.The supercell,strong echo cell and short-band echo in frontal echo zone and frontal warm zone can also form short-term heavy rainfall and produce heavy rain.On the vertical profile,the upper edge of 0 dBz strong echo of convective precipitation is more than 12 km,the top height of 45 dBz strong echo is more than 6 km,and the echo center intensity is 55-60 dBz,sometimes the false echo caused by side lobes appears above the strong echo.The upper edge of 0 dBz echo of mixed pre

关 键 词：城区暴雨 短时强降水 V-3Θ图 超级单体 絮状回波带 列车效应 低质心降水 

分 类 号：P458.1211[天文地球—大气科学及气象学] X43[环境科学与工程—灾害防治]