摘要
利用三维(ADTD-2C)和二维(ADTD)闪电定位系统资料,对比分析了湖北省一次特大暴雨过程中两套系统闪电活动特征,得出以下结论:(1)本次过程中地闪多于云闪,二者均以负极性为主。(2)三维系统正地闪在地闪中的占比低于正云闪在云闪中的占比,高于二维系统正地闪在地闪中的占比。(3)三维系统雷电流幅值集中分布在0~30 kA,较二维系统(10~50 kA)更集中,三维系统的雷电流累积概率较湖北省多年统计结果明显偏小,二维系统的雷电流累积概率略高于统计值。(4)两套系统总地闪和负地闪活跃时段基本一致。(5)两套闪电定位系统地闪密集区基本一致,且和云闪密集区基本重合,闪电分布集中程度高,主要分布在槽前正涡度平流区。三维系统地闪密度大于二维系统,最大值分别为5.78 fl/(km^(2)·d)和2.39 fl/(km^(2)·d)。三维系统中正、负闪电交错分布,二维系统中正、负地闪局部存在空间分离现象。(6)云闪密度大小与二维地闪相当、水平分布特征与三维地闪一致。垂直方向上,云闪主要发生在10 km以下,其中2~4 km云闪分布密集,占总云闪的47.24%。
The present study uses the lightning data from three-dimensional(3D;ADTD-2C)and twodimensional(2D;ADTD)lightning location systems to analyze the lightning characteristics of a torrential rain in Hubei Province.The results show that:(1)there is more cloud-to-ground lightning(CG)than intracloud lightning(IC)and both are mainly negative flashes.(2)The proportion of positive intra-cloud lightning(PIC)in IC is higher than that of positive cloud-to-ground lightning(PCG)in CG detected by the 3D system,which is higher than that detected by the 2D system.(3)The lightning current intensity detected by the 3D system has a smaller range(0~30 kA)than the one(10~50 kA)detected by the 2D system.(4)The active periods of negative CG and CG are basically the same.(5)The concentrated regions of IC and CG flashes have similar distributions on the positive vorticity regions.Lightning density of CG detected by the 3D system is higher than that detected by the 2D system,with the maximum values being 5.78 flashes/(km^(2)·d)and 2.39 flashes/(km^(2)·d),respectively.According to the 3D system,the positive and negative lightning are interlaced.By contrast,according to the 2D system,they have a spatial isolation distribution.(6)The density of cloud flashes is equivalent to that of CG detected by the 2D system,and its horizontal distribution characteristics are consistent with those of the CG detected by the 3D system.In the vertical direction,most IC occurs at the height below 10 km and mainly concentrates at the height between 2 to 4 km,accounting for 47.24%of the total IC.
作者
成勤
张科杰
刘俊
夏羽
毛成忠
CHENG Qin;ZHANG Kejie;LIU Jun;XIA Yu;MAO Chengzhong(Yichang Weather Bureau,Yichang 443000,China;Hubei Lightning Protection Center,Wuhan 430074,China)
出处
《热带气象学报》
CSCD
北大核心
2021年第3期396-408,共13页
Journal of Tropical Meteorology
基金
湖北省气象局科技发展基金项目(2020J02)
中国气象局预报员专项项目(CMAYBY2020-084)
湖北省防雷中心科技项目(FL-Y-2019008)
三峡库区局地气候监测系统维持-宜昌立体剖面保障项目(SK2019027)
三峡库首区地质灾害气象精细化预报试点项目(2020057)共同资助。
关键词
三维闪电定位系统
二维闪电定位系统
闪电频数
闪电密度
时空分布
3D lightning location system
2D lightning location system
lightning frequency
lightning density
temporal and spatial distribution
