基于高时间分辨率快电场变化资料的北京地区地闪回击统计特征

黎勋; 郄秀书; 刘昆; 王宇; 王东方; 刘明远; 孙竹玲; 张鸿波

doi:10.3878/j.issn.1006-9585.2016.16007

基于高时间分辨率快电场变化资料的北京地区地闪回击统计特征

doi: 10.3878/j.issn.1006-9585.2016.16007

黎勋^{1, 2,},
郄秀书²,
刘昆^1, ,,
王宇²,
王东方²,
刘明远²,
孙竹玲²,
张鸿波²

1.
成都信息工程大学, 成都 610225
2.
中国科学院大气物理研究所, 北京 100029

基金项目:

国家重点基础研究发展计划（973项目） 2014CB441401

国家自然科学基金 41305005

详细信息

作者简介:
黎勋, 女, 1990年出生, 硕士, 主要从事雷电科学与防护技术研究。E-mail:lixun@mail.iap.ac.cn

通讯作者:
刘昆, E-mail:liukun@cuit.edu.cn

中图分类号: P427.32⁺1
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- 被引次数: 0
出版历程
- 收稿日期: 2016-01-08
- 网络出版日期: 2016-05-31
- 刊出日期: 2017-03-20

Characteristics of Cloud-to-Ground Lightning Return Strokes in Beijing Based on High Temporal Resolution Data of Fast Electric Field Change

1.
Chengdu University of Information Technology, Chengdu 610225
2.
Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029

Funds:

National Basic Research Program of China 973 Program 2014CB441401

National Natural Science Foundation of China 41305005

摘要

摘要: 利用2014年北京闪电网观测到的4站及以上同步高时间分辨率闪电快电场变化资料，对北京地区5次雷暴过程中304次正地闪和1467次负地闪的回击特征进行了统计分析，主要包括：回击次数、10%~90%上升时间、下降时间、半峰值宽度、回击间隔、回击峰值电场强度、回击间隔和回击序数的关系等。结果表明，正、负地闪中单回击地闪所占比例分别为91.1%和24.2%，单次负地闪的平均回击次数为3.8次，观测到的最大回击数可达20次。304次正地闪首次回击的10%~90%上升时间、下降时间和半峰值宽度的算术平均值分别为4.2 μs、14.5 μs和6.2 μs；29次正地闪继后回击对应值分别为3.6 μs、12.6 μs和5.7 μs；1467次负首次回击的对应值分别为2.4 μs、23.9 μs和5.3 μs；4109次负继后回击的对应值分别为1.7 μs、19.5 μs和3.4 μs。正、负地闪回击间隔的几何平均值分别为106 ms和59 ms。负地闪回击间隔呈对数正态分布，平均回击间隔随着回击序数的增加有逐渐减小的趋势。最后，还对70次正回击、421次负首次回击和789次负继后回击峰值电场进行了统计，将其归一化到100 km的平均值分别为11.2 V/m、7.2 V/m和5.0 V/m。平均来看，负地闪首次回击峰值电场比继后回击峰值电场大1.4倍，但是有23.5%的继后回击峰值电场大于其对应的首次回击。
- 正地闪 /
- 负地闪 /
- 回击过程 /
- 波形特征参数 /
- 北京地区
Abstract: Return stroke waveform characteristics of 304 positive cloud-to-ground (CG) flashes and 1467 negative CG flashes observed during five storms in Beijing region were analyzed based on high temporal resolution data of fast electric field change collected by Beijing Lightning Network (BLNET). Characteristic parameters presented in this work are:The number of strokes per flash, 10%-90% risetime, falling time, full width at half maxmum (FWHM), interstroke interval, peak electric field and the relationship between the interstroke interval and stroke order, etc. The results indicate that the percentages of single stroke in positive and negative CG flashes were 91.1% and 24.2%, respectively. The average number of stroke per flash for negative CG flashes was 3.8 and the max stroke number was 20. The arithmetic means of 10%-90% risetime, falling time, and half-peak width for the 304 first strokes of positive CG flashes were 4.2 μs, 14.5 μs, and 6.2 μs; the corresponding values for the 29 subsequent strokes of positive CG were 3.6 μs, 12.6 μs, and 5.7 μs; the corresponding values for the 1467 negative first strokes were 2.4 μs, 23.9 μs, and 5.3 μs, and the corresponding values for the 4109 negative subsequent strokes were 1.7 μs, 19.5 μs, and 3.4 μs, respectively. In addition, interstroke intervals of positive and negative CG flashes showed a more or less log-normal distribution and yielded the geometric mean values of 106 ms and 59 ms. Moreover, the geometric mean interstroke interval for negative CG flashes of particular multiplicity tended to decrease with the stroke order. Finally, peak electric fields of the 70 positive, 421 negative first, and 789 negative subsequent strokes, when normalized to 100 km, were 11.2 V/m, 7.2 V/m, and 5.0 V/m, respectively. On average, peak electric field for the first stroke was 1.4 times larger than its subsequent counter part for negative CG flashes. However, about 23.5% of subsequent return strokes were stronger than the corresponding first stroke.
- Positive CG flashes /
- Negative CG flashes /
- Return stroke /
- Waveform characteristic parameter /
- Beijing region

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图 1 快电场波形特征参数的定义

Figure 1. Definition of characteristic parameters of fast electric field waveform

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图 2 （a）正地闪、（b）负地闪回击次数分布

Figure 2. Stroke multiplication distribution of CG lightning: (a) Positive CG flashes; (b) negative CG flashes

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图 3 （a）正地闪、（b）负地闪10%~90%上升时间分布

Figure 3. Distribution of 10%−90% risetime for return stroke waveform: (a) Positive CG flashes; (b) negative CG flashes

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图 4 （a）正地闪、（b）负地闪下降时间分布

Figure 4. Falling time distribution of return stroke waveform: (a) Positive CG flashes; (b) negative CG flashes

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图 5 （a）正地闪、（b）负地闪回击间隔分布

Figure 5. Interstroke interval distribution: (a) Positive CG flashes; (b) negative CG flashes

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图 6 随回击序数变化的负地闪平均回击间隔

Figure 6. Stroke order versus geometric mean interstroke intervals for negative CG flashes

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图 7 （a）正地闪、（b）负地闪归一化到100 km的回击初始峰值电场分布

Figure 7. Distribution of the peak electric field normalized to 100 km: (a) Positive CG flashes; (b) negative CG flashes

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图 8 随回击序数变化归一化到100 km的平均初始峰值电场

Figure 8. The geometric mean of initial stroke peak electric field normalized to 100 km for different stroke orders

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表 1 5次雷暴中正地闪的比例

Table 1. Ratios of positive cloud-to-ground (CG) to total flashes in five thunderstorms

雷暴时间	地闪数	正地闪比例
2014-06-13	408	33.6%
2014-07-30	218	12.8%
2014-08-03	114	30.7%
2014-08-28	963	10.1%
2014-09-19	68	10.3%

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表 2 不同地区正、负地闪回击次数的结果对比

Table 2. Multiplicity for positive and negative CG flashes in different regions

	地区	样本数	单回击比例	最大回击数	平均回击次数	来源
负地闪	美国佛罗里达	76	17%	18	4.6	Rakov and Uman (1990)
	瑞典	137	18%	10	3.4	Cooray and Pérez (1994)
	德国	81	—	—	2.4	Heidler and Hopf (1998)
	中国内陆高原	50	39.80%	14	3.76	郄秀书等 (2001)
	巴西	233	20%	16	3.8	Saba et al.(2006)
	中国广州	570	28%	14	—	张义军等 (2013)
	美国佛罗里达	220	30.50%	16	4.5	Zhu et al.(2014)
	中国合肥	1085	24.30%	17	3.3	Zhu et al.(2015)
	中国北京	1467	24.20%	20	3.8	本文
正地闪	中国兰州	112	90.30%	2	—	郄秀书和郭昌明 (1990)
	中国北京	179	82.90%	5	—
	德国	45	73.30%	4	—	Heidler and Hopf (1998)
	中国那曲	45	91%	4	—	赵阳等 (2004)
	巴西	39	72%	3	1.33	Saba et al.(2010)
	中国大兴安岭	185	94.60%	3	1.1	Qie et al.(2013)
	中国北京	304	91.10%	4	1.1	本文

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表 3 正、负地闪回击半峰值宽度

Table 3. Full width at half maxmum (FWHM) for strokes in positive and negative CG flashes

回击类型	样本数		算术平均值/μs		几何平均值/μs		方差/μs		最小值/μs		最大值/μs
回击类型	正地闪	负地闪	正地闪	负地闪	正地闪	负地闪	正地闪	负地闪	正地闪	负地闪	正地闪	负地闪
首次回击	304	1467	6.2	5.3	4.8	3.7	4.4	20.3	0.8	0.6	23.1	585
继后回击	29	4109	5.7	3.4	4.5	2.8	4.2	3.2	1.4	0.2	16.6	135

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表 4 不同地区正、负地闪回击间隔的对比

Table 4. Interstroke intervals of positive and negative CG flashes in different regions

	地区	样本数	算术平均值/ms	几何平均值/ms	方差/ms	最小值/ms	最大值/ms	来源
负地闪	瑞典	568	65	48	—	2.5	376	Cooray and Pérez (1994)
	德国	414	87	60	96	—	—	Heidler and Hopf (1998)
	中国内陆高原	238	64.3	46.6	—	4.8	328.5	郄秀书等 (2001)
	巴西	608	83	61	—	2	782	Saba et al.(2006)
	美国佛罗里达	780	80	53	—	0.1	552	Zhu et al.(2014)
	中国合肥	2525	80	62	—	—	—	Zhu et al.(2015)
	中国北京	4109	88	59	99	0.4	792	本文
正地闪	瑞典	29	92	64	—	68	290	Cooray and Pérez (1994)
	德国	16	120	101	97	—	—	Heidler and Hopf (1998)
	巴西	13	168	117	131	20	406	Saba et al.(2010)
	中国北京	29	160	106	162	17	787	本文

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表 5 不同地区正、负地闪归一化到100 km的回击初始峰值电场大小对比

Table 5. The peak electric fields of positive and negative CG flashes normalized to 100 km in different regions

	地区	样本数	算术平均值/V m^-1	几何平均值/V m^-1	方差/V m^-1	来源		地区	首次回击				继后回击				来源
	地区	样本数	算术平均值/V m^-1	几何平均值/V m^-1	方差/V m^-1	来源		地区	样本数	算术平均值/	几何平均值/	方差/V m^-1	样本数	算术平均值/V m^-1	几何平均值/V m^-1	方差/V m^-1	来源
正地闪	中国兰州	—	14.8	—	—	郄秀书和郭昌明 (1990)	负地闪	美国佛罗里达	75	9.9	—	6.8	163	5.7	—	4.5	Tiller et al.(1976)
	丹麦	46	15.7	—	6.7	Cooray et al.(2004)		美国恩斯维尔	51	6.7	—	3.8	83	5.0	—	2.2	Lin et al.(1979)
	中国北京	117	13.7	—	8.7	张阳等 (2010)		美国奥卡拉	29	5.8	—	2.5	59	4.3	—	1.5
	巴西	66	17.0	13.4	12.3	Schumann et al.(2013)		美国佛罗里达	112	6.2	—	3.4	237	3.9	—	2.2	Master et al.(1984)
	中国北京	70	11.2	9.9	5.0	本文		中国北京	421	7.2	6.2	4.1	789	5.0	4.2	3.4	本文

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