贵州省近10年地闪分布特征分析

PRELIMINARY ANALYSIS OF CLOUD TO GROUND LIGHTNING IN GUIZHOU PROVINCE IN RECENT 10 YEARS

关键词:  地闪频次雷电流幅值雷电流陡度密度

Key words:  cloud to ground  frequency  lightning current amplitude  lightning current gradient  density

摘要:

［目的］为系统分析研究贵州省地闪活动规律。［方法］利用2008—2017年ADTD闪电定位监测资料，主要采用数理统计和分析方法，结合ArcGIS插值，［结果］贵州省年平均地闪频次为44515 3万次，负地闪占总地闪的9561%， 3—10月、15h开始至次日2h闪电发生频繁，负地闪月分布呈现“双峰”特征，正地闪月分布呈现“单峰”特征，正地闪比例与总地闪频数发展趋势相反，地闪密度呈明显的西高东低区域分布； 年平均雷电流强度为4114kA， 12月、10h雷电流强度最强， 02h~13h的平均雷电流强度明显大于14h至次日01h； 雷电流强度主要集中在10~50kA，占总地闪数的7921%，贵阳市平均总地闪雷电流强度最大，为4532kA，在高海拔地区正地闪的平均强度随着海拔高度上升不断增加； 总地闪平均陡度为10350kA/μs，陡度在82kA/μs以上的地闪频次占总地闪频次的50%。［结论］分析得出了贵州省地闪频次、雷电流幅值的时空分布、陡度分布特征，得到了雷电流幅值累积概率公式。

Abstract:

This research is intended to systematically analyze and study CG（cloud to ground）activity rules of Guizhou province. Based on the ADTD（Active Divectory Topology Diagrammer）lightning location monitoring data from 2008 to 2017, this research mainly used mathematical statistics and analysis methods, and combined with ArcGIS interpolation. The results were shown as follows. Average lightning of frequency were 445153 fl/year in Guizhou province. The percentage of negative CG in total CG was 95.61%. The high incidence period of lightning activities focused on between March and October in a year and from pm.15 to the next day am.2. The monthly distribution of negative lightning showed the characteristics of "bimodal", and the "single peak" distribution was presented in the positive lightning monthly distribution. The positive lightning in contrast to the trend of the total lightning frequency the lightning density was obviously distributed, in regional differences with an overall tendency of high west to low east. The average total lightning current intensity in Guiyang was 41.14kA/year, the high incidence period of lightning activities was at am.10 in December. The average total lightning current intensity in am.2 pm.13 was bigger than in pm.14 next day am.01.The lightning intensities mainly appeared in the range from 10kA to 50kA. The percentage in total lightning was 79.21%. The average total lightning current intensity in Guiyang was 45.32kA. The average lightning current amplitude at high altitude increased with altitude. The average total lightning current gradient was 10.350kA/?s. The lightning current gradient of the steepness in the 8.2kA/s above was 50% of the total lightning. The spatial and temporal distribution and steepness distribution of lightning current amplitude and lightning frequency in Guizhou province are analyzed and the cumulative probability formula of amplitude is obtained.