天气雷达三体散射长钉回波特征分析  

Analysis of Echo Characteristics of Three-Body Scatter Spike for Weather Radar

作　　者：孟蕾[1,2] 桑友伟 夏扬[3] 高文娟 刘达之 MENG Lei;SANG Youwei;XIA Yang;GAO Wenjuan;LIU Dazhi(Hunan Branch of CMA Training Centre,Changsha 410125;Key Laboratory of Hunan Meteorological Disaster Prevention and Mitigation,Changsha 410118;CMA Training Centre,Beijing 100081)

机构地区：[1]中国气象局气象干部培训学院湖南分院,长沙410125 [2]气象防灾减灾湖南省重点实验室,长沙410118 [3]中国气象局气象干部培训学院,北京100081

出　　处：《气象》2024年第6期675-685,共11页Meteorological Monthly

基　　金：中国气象局气象干部培训学院重点项目(2022CMATCZD12);湖南省气象局研究型业务预报预测专项(XQKJ22C011);湖南省气象局2024年创新发展专项(CXFZ2024-FZZX46)共同资助。

摘　　要：利用2016—2020年中国中东部地区47个强对流个例中50部S波段多普勒天气雷达的基本反射率因子产品资料,在筛选出2626个样本的基础上,分析三体散射长钉(TBSS)特征。结果表明:TBSS在1.5 km和5 km高度附近出现频次最高;在2.4°仰角出现频次最高。TBSS主要出现在雷达静锥区边缘至雷达径向距离210 km范围,在距离雷达115 km附近达到峰值;TBSS在雷达极坐标系中呈现南多北少、西多东少的形势;当对流风暴移动方向与雷达径向方向的夹角大于30°时有利于观测到TBSS。TBSS回波强度在起始端径向向外0~15 km范围内迅速降低至5 dBz,15 km之后在-5~10 dBz波动,TBSS区域中70%以上为低于25 dBz的弱回波;99%的TBSS长度小于40 km,不同长度的TBSS形态符合正态分布。TBSS出现频次和长度与强回波的中心最高值和区域面积没有显著相关关系。Using the basic reflectivity factor PPI image data of 47 severe convective cases from 50 S-band Doppler weather radars in the central-eastern region of China from 2016 to 2020,the three-body scatter spike(TBSS)characteristics are analyzed based on the screening of 2626 TBSS samples.The results show that TBSS is most frequently observed at altitudes of 1.5 km and 5 km and at the elevation 2.4°.TBSS is mainly observed in the range from the edge of the radar static cone area to the radar radial distance of 210 km.It reaches its peak at the spot 115 km away from the radar.In the radar polar coordinate system,TBSS appears more in the south than in the north,and more in the west than in the east.It is better to observe TBSS when the angle between the moving direction of the convective storm and the radial direction of the radar is larger than 30°.The TBSS echo strength decreases rapidly to 5 dBz within 0-15 km radially outward from the beginning,and fluctuates in the range of-5 and 10 dBz after 15 km,with more than 70%of the TBSS zone being weak echoes weaker than 25 dBz.99%of TBSS length is under 40 km,and the patterns of TBSSs with varying lengths follow a normal distribution.No significant correlation is found between the frequency and length of TBSS occurrences and the highest value of the high echo core and the area of the high echo.

关 键 词：三体散射长钉(TBSS) 天气雷达 分布特征 雷达回波 冰雹 

分 类 号：P412[天文地球—大气科学及气象学]