基于多源观测资料研究重庆地区一次风雹过程  

Research on a hailstorm process in Chongqing based on multi-source observation data

作　　者：邹倩 左春艳 吴政谦 翟丹华 牟容 ZOU Qian;ZUO Chunyan;WU Zhengqian;ZHAI Danhua;MU Rong(CMA Key Open Laboratory of Transforming Climate Resources to Economy,Chongqing Meteorological Observatory,Chongqing 401147,China;Chongqing Shapingba Meteorological Bureau,Chongqing 400030,China)

机构地区：[1]中国气象局气候资源经济转化重点开放实验室,重庆市气象台,重庆401147 [2]重庆沙坪坝区气象局,重庆400030

出　　处：《干旱气象》2024年第4期598-610,共13页Journal of Arid Meteorology

基　　金：国家自然科学基金面上项目(42175040);中国气象局预报员专项(CMAYBY2020-107)共同资助。

摘　　要：为认识风雹发生前后对流系统的热动力演变特征,加强新型探测资料在风雹监测预警中的应用,利用微波辐射计、风廓线雷达、多普勒雷达等观测资料,对2014年4月18日凌晨发生在重庆西部地区的一次强风雹天气过程进行分析。结果表明:此次风雹过程为典型的低层暖平流强迫类强对流天气,雷达回波悬垂特征和径向速度辐合明显。风雹发生前,微波辐射计反演的温湿度跃增明显,风雹发生前1.0~3.0 h,K指数、850 hPa与500 hPa假相当位温差(θ_(se850-500))、对流有效位能(Convective Available Potential Energy,CAPE)、0~3 km垂直风切变(Vertical Wind Shear,SHR_(0-3))等指数随时间临近明显递增,大气折射率结构常数(Cn^(2))在风雹发生前0.2~0.5 h达到波峰,风廓线雷达显示中低层的垂直速度随高度波动较大;多次风雹过程的参数共性显示,风雹发生前0~0.5 h,微波辐射计25.00 GHz亮温、Cn^(2)和大气折射率结构常数面积(S_(Cn^(2)))都有明显增加趋势,风雹发生前0~10 min,(S_(Cn^(2)))均大于-500 dB·km阈值。观测站降雹时,垂直积分液态水和地面到高空的垂直速度差均达到最大,Cn^(2)在中低层跃增大于阈值-120 dB。以上特征对识别风雹的发生有较好指示意义。In order to understand the thermodynamic evolution characteristics of the convective system before and after the occurrence of hailstorm,and strengthen the application of new detection data in hailstorm monitoring and early warning,a strong hailstorm weather process occurring in the western of Chongqing in the early morning of April 18,2014 was analyzed by using the observation data of mi⁃crowave radiometer,wind profiler radar and Doppler radar.The results show that the hailstorm process was a typical strong convective weather forced by low-level warm advection,and the radar echo overhanging characteristics and radial velocity convergence were obvi⁃ous.Before the occurrence of the hailstorm,the temperature and humidity retrieved by microwave radiometer data increased signifi⁃cantly.From 1.0 to 3.0 hours before the occurrence of hailstorm,K index,850 hPa and 500 hPa pseudo-equivalent potential tempera⁃ture differenc(θ_(se850-500)),CAPE(Convective Available Potential Energy),vertical wind shear from 0 to 3 km(SHR_(0-3))etc.increased sig⁃nificantly with time.The atmospheric refractive index structure constant(Cn^(2))increased to its peak within 0.2 to 0.5 hours before the oc⁃currence of hailstorm,and the vertical velocity observed by wind profile radar in middle and lower layers,fluctuated significantly with height.The commonness of the parameters of multiple hail processes show that the brightness temperature of 25.00 GHz,Cn^(2) and the area of atmospheric refractive index structure constant(S_(Cn^(2))) of microwave radiometer had a significant increase trend within half hour before the occurrence of hail,and S_(Cn^(2)) was greater than the threshold of-500 dB·km within 10 minitutes before the occurrence of hail⁃storm.The vertical integral liquid water and the vertical velocity difference from the ground to the high altitude reached the maximum when the hail fell on the ground,and the Cn^(2) jumped to the threshold value of-120 dB in the middle and low layers.All the characteris⁃tics mentioned abo

关 键 词：“4·18”风雹 微波辐射计 风廓线雷达 不稳定参数 

分 类 号：P412[天文地球—大气科学及气象学]