论文

负地闪不规则脉冲簇事件的宽带干涉仪三维观测

  • 刘恒毅 ,
  • 董万胜 ,
  • 张义军 ,
  • 郑栋 ,
  • 严碧武 ,
  • 石玉恒 ,
  • 吴亭
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  • 中国气象科学研究院 灾害天气国家重点实验室, 北京100081;2. 国网电力科学研究院, 湖北 武汉430074;? 3. 北京市气象局, 北京100089

网络出版日期: 2013-08-28

Three-Dimensional Observation of Chaotic Pulse Train Event in Negative Cloud-to-Ground Lightning Using VHF Broadband Digital Interferometer

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Online published: 2013-08-28

摘要

利用宽带干涉仪的三维观测数据, 对发生在负地闪继后回击前的不规则脉冲簇事件CPT进行了研究。首先对CPT事件快电场时域波形特征进行了分析, 然后, 研究了CPT事件的辐射源时空发展特征, 并对这些CPT事件、 梯级先导和直窜先导在30~290 MHz频段辐射信号的功率谱密度进行了对比分析。结果表明, 10次CPT事件的快电场脉冲间隔平均值和标准差分别为5.3~9.0 μs和2.7~4.9 μs。CPT事件的击穿过程为负极性击穿, 其发展特征与直窜先导或企图先导没有明显区别。10次CPT辐射源发展速度的统计结果表明, 平均发展速度在3.23×106~1.93×107 m·s-1之间, 平均值为1.02×107 m·s-1, 与企图先导或直窜先导的速度统计结果相当。10次CPT事件在30~290 MHz频段的功率谱密度平均值分别比同次地闪中的梯级先导和直窜先导强1.8~11.6 dB和2.4~12 dB。

本文引用格式

刘恒毅 , 董万胜 , 张义军 , 郑栋 , 严碧武 , 石玉恒 , 吴亭 . 负地闪不规则脉冲簇事件的宽带干涉仪三维观测[J]. 高原气象, 2013 , 32(4) : 1186 -1194 . DOI: 10.7522/j.issn.1000-0534.2012.00111

Abstract

The chaotic pulse train (CPT) events occurred in negative cloud-to-ground flashes were imaged by  three dimensions VHF broadband digital interferometers.10 negative cloud-to-ground flash records were analyzed. The characteristics of the fast electric field change waveform of CPT were analyzed. The results show that the mean value and standard deviation of the pulse separations in these chaotic pulse trains are 5.3~9.0 μs and 2.7~4.9 μs, that is consistent with previous result. Then, the spatial and temporal characteristics, power spectral density  from 30 MHz to 290 MHz band and pulse train structure of 10 CPT records are analyzed and the results are compared with those of step leader and subsequent leader. It is found that the breakdown process associated with CPT is negative and similar with attempt leader or dart leader. The statistical result shows the average progression speeds of 10 CPT events are about 3.23×106~1.93×107 m·s-1 with the mean value of 1.02×107 m·s-1, that is also similar with that of attempt leader and dart leader. In the 10 records, the average power spectral density  of the CPT in the 30~290 MHz band is 1.8~11.6 dB and 2.4~12 dB larger than that of the step leader and dart leader in the same negative cloud-to-ground lightning.

参考文献

[1]Weidman C D. The submicrosecond structure of lightning radiation fields[D]. Tucson: University of Arizona, 1982.
[2]Rakov V A, Uman M A. Lightning: Physics and Effects[M]. Cambridge: Cambridge University Press, 2003.
[3]Gomes C, Cooray V, Fernando M, et al. Characteristics of chaotic pulse trains generated by lightning flashes[J]. Journal of Atmospheric and Solar-Terrestrial Physics, 2004, 66(18): 1733-1743.
[4]Rakov V A, Uman M A. Some properties of negative cloud-to-ground lightning flashes versus stroke order[J]. J Geophys Res, 1990, 95(D5): 5447-5453.
[5]Willett J, Bailey J, Leteinturier C, et al. Lightning electromagnetic radiation field spectra in the interval from 0.2 to 20 MHz[J]. J Geophys Res, 1990, 95(D12): 20367-20387.
[6]Mdkeld J S, Edirisinghe M, Fernando M, et al. HF radiation emitted by chaotic leader processes[J]. Journal of Atmospheric and Solar-Terrestrial Physics,2007, 69(6): 707-720.
[7]Davis S M. Properties of lightning discharges from multiple-station wideband electric field measurements[D]. Gainesville: University of Florida, 1999.
[8]董万胜, 刘欣生, 陈慈萱, 等. 用宽带干涉仪观测云内闪电通道双向传输的特征[J]. 地球物理学报, 2003, 46(3): 317-321.
[9]董万胜, 刘欣生, 张义军, 等. 云闪放电通道发展及其辐射特征[J]. 高原气象, 2003, 22(3): 221-225.
[10]Dong W, Liu X, Zhang Y, et al. Observations on the leader-return stroke of cloud-to-ground lightning with the broadband interferometer[J]. Science China Earth Sciences,2002, 45(3): 259-269.
[11]董万胜, 刘欣生, 张义军. 一次人工触发闪电的宽带干涉仪观测[J]. 科学通报, 2001, 46(5): 427-432.
[12]董万胜. 闪电宽带干涉仪系统及其观测研究[D]. 兰州: 中国科学院寒区旱区环境与工程研究所, 2000.
[13]邱实. 闪电宽带干涉仪辐射源定位技术及其初步观测研究[D]. 南京: 中国人民解放军理工大学, 2008.
[14]Shao X, Krehbiel P, Thomas R, et al. Radio interferometric observations of cloud-to-ground lightning phenomena in Florida[J]. J Geophys Res, 1995, 100(D2): 2749-2783.
[15]董万胜, 刘欣生, 张义军, 等. 25~100MHz频段闪电脉冲辐射能量频谱特征[J]. 中国电机工程学报, 2003, 23(3): 104-107.
[16]Fisher R, Schnetzer G, Thottappillil R, et al. Parameters of triggered-lightning flashes in Florida and Alabama[J]. J Geophys Res, 1993, 98(D12): 22887-22902.
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