摘要
研究暴雪雷达回波特征是为了更好地开展暴雪短临预警预报与服务工作。使用常规天气资料和天气雷达、风廓线雷达等非常规资料,采用统计分析、中尺度分析、回波形态分析等方法,对江西2014年、2016年和2018年3次暴雪天气过程进行对比分析。结果表明:江西暴雪过程大多数发生在赣北、赣中地区,除高山站庐山外,九江、修水和南昌也是降雪中心,最大雪深12.6~20.0 cm,降雪区最南可到达吉安西部和赣州北部。暴雪天气的主要系统配置:500 hPa处高空槽前,850 hPa和700 hPa为切变线、西南急流。在降雪前,1000 hPa温度在0℃以上;降雪出现时,1000 hPa温度在0℃以下,大雪时可达-4℃;700 hPa与1000 hPa温度比较接近,并且700 hPa温度高于850 hPa,出现明显逆温层。雪回波一般在5~20 dBZ,暴雪回波强度在30 dBZ左右;降雨回波强度>20 dBZ,为20~40 dBZ;雨夹雪回波中,最强雨回波可以发展到40 dBZ以上,呈团絮状回波结构。暴雪反射率因子垂直结构上回波伸展高度在5~7 km,2~3 km附近有20~30 dBZ的较强回波带。径向速度场上,零速度线在1.5~2 km,其以下为负速度区,以上为正速度区。在雷达拼图上可以同时观测到雪回波、雨夹雪回波和雨回波三种相态共存的回波特征。上饶风廓线上0.9~3.2 km存在偏东风与偏西风的风切变层。雪在TWP3和TWP8两种风廓线雷达上表现不同,信噪比SNR分别为:20~35 dB和35~50 dB;而垂直速度W为0~4 m·s-1。
The study of blizzard radar echo characteristics is to better carry out blizzard short-term and imminent warning and forecasting and service work.Using conventional weather data and unconventional data such as weather radar,wind profiler radar and numerical forecast,the three snowstorm weather processes in Jiangxi in 2014,2016 and 2018 were compared and analyzed by statistical analysis,mesoscale analysis,echo morphology analysis and comparative test.The results show that the snowstorm process in Jiangxi mostly occurs in northern and central Jiangxi.Besides the mountain station Lushan,Jiujiang,Xiushui and Nanchang are also snow centers.the heaviest snow is 12.6~20.0 cm deep,and the southernmost snow area can reach the west of Ji’an and the north of Ganzhou.The main system configuration of blizzard weather is:in front of the upper trough at 500 hPa,shear line and southwest jet at 850 hPa and 700 hPa.Before snowfall,the temperature of 1000 hPa was above 0℃.When snowfall occurs,the temperature at 1000 hPa is below 0℃and can reach-4℃when heavy snowfall occurs.The temperature at 700 hPa is close to 1000 hPa,and the temperature at 700 hPa is higher than 850 hPa,showing obvious inversion layer.Snow echo is usually 5~20 d BZ,and blizzard echo intensity is about 30 dBZ.Rain echo intensity is often more than 20~40 dBZ;In the sleet echo,the strongest rain echo can develop to more than 40 dBZ,showing a flocculent echo structure.In the vertical structure of blizzard reflectivity factor,the echo stretching height is 5~7 km,and there is a strong echo band of 20~30 dBZ near 2~3 km.In the radial velocity field,the zero velocity line is 1.5~2 km,below which is the negative velocity zone and above which is the positive velocity zone.Echo characteristics of snow echo,sleet echo and rain echo coexisting in three phases can be observed simultaneously on radar mosaic.There is a wind shear layer with easterly and westerly winds between 0.9~3.2 km on Shangrao wind profile.Snow shows different performance on TWP3 and TWP8 wind prof
作者
陈鲍发
马中元
谌芸
王立志
余剑浩
卢秋芳
郑卡妮
张晓芳
CHEN Baofa;MA Zhongyuan;CHEN Yun;WANG Lizhi;YU Jianhao;LU Qiufang;ZHENG Kani;ZHANG Xiaofang(National Meteorological Center,Beijing 100081,China;Jiangxi Institute of Meteorological Sciences,Nanchang 330046,China;Jingdezhen Meteorological Bureau,Jingdezhen 333000,China;Institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 100029,China;Yingtan Meteorological Bureau,Yingtan 335000,China;Shangrao Meteorological Bureau,Shangrao 334000,China)
出处
《沙漠与绿洲气象》
2020年第4期35-45,共11页
Desert and Oasis Meteorology
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)
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(BJG201205)
江西省重点研发计划项目(20171BBG7005)
景德镇市科技计划项目(2017NYSF002)。
关键词
逆温层
雷达拼图
回波垂直结构
风廓线特征
inversion layer
radar mosaic
echo vertical structure
wind profile characteristics
