摘要
为了研究江西昌江流域特大暴雨过程中短时强降水的回波特征,使用天气、雷达回波和昌江流域气象水文雨量等资料,对2000—2020年昌江流域10次特大暴雨过程,采用天气学、统计学、雷达气象学和图像处理学等方法进行研究。结果表明:特大暴雨过程的主要取决于对流活动造成的短时强降水,包括短时强降水雨强和强降水范围。当3 h累计雨量≥100 mm时即可提前发布特大暴雨红色预警,监测单站累计时长达3 h的短时强降水可更早发布预警,提升特大暴雨预报服务效果。超低空急流、中低层低涡、高空低槽、低层辐合、高层辐散在景德镇市特大暴雨过程中发挥了重要作用。强降水由大范围混合性降水中的强回波单体、强回波短带或其他回波导致,回波强度达45~55 dBz。风暴跟踪信息(STI)产品不仅能反映强回波的移动信息,还可以分析出回波的辐合,对于短时临近预报有很好的参考价值。在覆盖江西宽广东西走向的回波带上,存有多条南北走向的短带回波,由西向东移动,形成“列车效应”,风廓线雷达产品垂直速度W可大致反映回波移动情况。造成特大暴雨的组合反射率(CR)强度多为45~50 dBz,回波顶高(ET)平均为12~13 km,垂直液态水含量(VIL)在5~10 kg·m^(-2),45 dBz的强回波伸展高度平均为6 km。CR强度在45 dBz以上时:强回波面积达到3等级时出现短时强降水的可能性很大,强回波面积在2等级时雨强大多在20~30 mm·h^(-1);强回波面积在1等级时雨强基本在20 mm·h^(-1)以下。研究结果为了解和监测预警昌江流域特大暴雨的短时强降水回波特征及预报提供了参考依据。
In order to study the echo characteristics of short-term heavy rainfall in the process of severe rainstorm in Changjiang River Basin,by using the data of weather,radar echo and meteorological,hydrological and rainfall in Changjiang River Basin,as well as the methods of meteorology,statistics,radar meteorology and image processing,this paper studies 10 severe rainstorm processes in Changjiang River Basin from 2000 to 2020.The results show that the severe rainstorm process mainly depends on the short-term heavy rainfall caused by convective activities,including the short-term heavy rainfall and the range of heavy rainfall.When the accumulated rainfall of 3 h is≥100 mm,the red warning of severe rainstorm can be issued in advance.The monitored short-term heavy rainfall accumulated for 3 h at a single monitoring station can be issued earlier to improve the effect of severe rainstorm prediction service.Ultra low-level jet,low-level vortex,high-altitude trough,low-level convergence and high-level divergence play an important role in the process of severe rainstorm in Jingdezhen City.Heavy precipitation is caused by strong echo cell,strong echo short band or other echoes in a wide range of mixed precipitation,and the echo intensity is 45-55 dBz.STI product information can not only reflect the movement information of strong echo,but also analyze the convergence of echo,which has a good reference value for short-term and imminent prediction.On the echo band covering Jiangxi east-west direction,there are many short band echoes in south-north direction,which move from west to east to form“train effect”.The vertical velocity of wind profile radar product can roughly reflect the echo movement.The CR intensity causing the torrential rain is mostly 45-50 dBz,the average height of echo top is 12-13 km,the VIL is 5-10 kg·m^(-2),and the average extension height of strong echo of 45 dBz is 6 km.When the CR intensity is above 45 dBz:the strong echo area reaches Grade 3,and there is a great possibility of short-term heavy precipitation.The strong echo area is in Grade 2,mostly between 20-30 mm·h^(-1).When the strong echo area is at Grade 1,the precipitation intensity is basically below 20 mm·h^(-1).These research results could provide a reference basis for understanding,monitoring and early warning the echo characteristics and prediction of short-term heavy rainfall in severe rainstorm in Changjiang River Basin.
作者
陈鲍发
马中元
王立志
黄龙飞
李燕玲
盛梦婷
张晓芳
CHEN Baofa;MA Zhongyuan;WANG Lizhi;HUANG Longfei;LI Yanling;SHENG Mengting;ZHANG Xiaofang(Jingdezhen Meteorological Office of Jiangxi Province,Jingdezhen 333000;Jiangxi Institute of Meteorological Sciences,Nanchang 330046;Institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 100029;Leping Meteorological Station of Jiangxi Province,Leping 333300;Wuyuan Meteorological Station of Jiangxi Province,Wuyuan 333200)
出处
《气象》
CSCD
北大核心
2022年第11期1418-1427,共10页
Meteorological Monthly
基金
中国科学院战略性先导科技专项(A类-XDA19040202)
国家自然科学基金项目(41975001)
江西省气象局2020年面上项目(JX2020M05)
江西省重点研发计划项目(20171BBG7005)共同资助。
关键词
昌江流域
特大暴雨
短时强降水
回波特征
强回波面积
Changjiang River Basin
severe rainstorm
short-term heavy rainfall
echo characteristic
strong echo area