Difference Between 2D and 3D Development Characteristics of an Upward Lightning Leader
-
摘要: 基于高时空分辨率的广州高建筑物雷电观测站双站(观测点1和观测点2)同步观测资料,对比分析2019年4月20日05:12(世界时)发生在广州塔上的一次上行闪电的先导二维和三维发展特征。分析表明:该上行闪电可三维重建的上行先导通道发展长度约为5.4 km,是对应两个观测点二维通道长度的1.5倍和1.38倍;由观测点1的高速摄像记录分析得到的上行先导二维发展速率变化范围为1.8×104~4.5×105 m·s-1(平均值为1.8×105 m·s-1);对应的上行先导三维发展速率变化范围为3.8×104~7.2×105 m·s-1(平均值为2.8×105 m·s-1);三维和二维发展速率之比变化范围为1~4.7,平均值为1.5;上行先导始发后10 ms内,三维与二维发展速率的变化趋势大致相同,均随高度增加而逐渐加快;10 ms后二维发展速率明显降低,平均值仅为10 ms内的42%,且随时间变化较小。而10 ms后的三维发展速率平均值为10 ms内的77%,随时间呈明显的不规则波动变化;先导通道与观测点间的距离以及通道发展方向与观测点视线方向的夹角是造成上行先导二维和三维发展速率差异的主要因素。Abstract: Tall object not only has a high probability of being struck by downward lightning, but also is easy to trigger upward lightning. Comparing with 2D optical observation, reconstructed 3D observation by dual-station optical observation can better reflect the real characteristics of the lightning channel. Based on the synchronous dual-station optical observations from the Tall-Object Lightning Observatory in Guangzhou (TOLOG), an upward lightning triggered by a nearby positive cloud-to-ground (CG) flash at Guangzhou Tower is investigated, and 2D and 3D development characteristics of the upward leader are compared.The result shows that the length of 3D channel is 5.4 km, which is 1.5 times of 2D channel. 3D channel is developed at a height of more than 4.6 km in the vertical direction and about 800 m in the horizontal direction. 2D speed ranges from 1.8×104 to 4.5×105 m·s-1, with an average of 1.8×105 m·s-1. 3D speed ranges from 3.8×104 to 7.2×105 m·s-1, with an average value of 2.8×105 m·s-1. Within 10 ms after the leader initiation, 3D and 2D speeds show roughly the same trend. After 10 ms, 2D rate decreases significantly and changes little over time, while 3D speed shows an obvious irregular fluctuation with time. The ratio of 3D speed and 2D speed ranges from 1 to 4.7, with an average of 1.5. The ratio remains stable at 1-2 for the first 10 ms after leader initiation and then shows irregular fluctuations with time. In fact, due to the change of horizontal development direction of the channel 10 ms after the leader initiation, the distance between the channel and the station-1 increases rapidly, leading to increasing speed difference between 3D and 2D observations. The cause for the fluctuation of 3D speed and 2D speed ratio is that the angle between the development direction of the channel and the sight direction of the observation station changes greatly. The results of 2D and 3D vary greatly at a certain stage of upward leader development, which further proves the importance of analyzing 3D development characteristics of lightning.
-
图 8 三维速率和二维速率差异
(a)三维速率和二维速率之比的实际值与理论值关系,(b)速率比实际值与理论值随时间变化, (c)三维闪电通道与观测点1在空间中的位置对比(灰色通道表示该部分三维速率与二维速率差异较大),(d)d1与φ随时间变化
Fig. 8 Differences in velocity between 3D and 2D
(a)actual ratio of 3D speed and 2D speed versus theoretical values of ratio, (b)changes of actual and theoretical ratio with time, (c)relative position of 3D reconstruction channel and station-1 in space (grey channel denotes huge difference between 3D and 2D speed), (d)changes of d1 and φ with ime
表 1 本研究所用光学观测设备详细信息
Table 1 Details of optical observation instruments in the study
设备编号 观测站点 帧率/s-1 空间分辨率 记录时长/ms 预触发时长/ms 焦距/mm HC-1 观测点1 20000 1024 × 1024 50 25 14 HC-3 观测点1 1000 1024 × 1024 1650 150 8 LCI-03 观测点2 50 780 × 582 5 -
[1] Rakov V A, Uman M A.Lightning:Physics and Effects.New York:Cambridge University Press, 2003. [2] Eriksson A J. Lightning and tall structures. Trans S Afr Inst Electr Eng, 1978, 69(8): 238-253. [3] 马瑞阳, 郑栋, 姚雯, 等. 雷暴云特征数据集及我国雷暴活动特征. 应用气象学报, 2021, 32(3): 358-369. doi: 10.11898/1001-7313.20210308Ma R Y, Zheng D, Yao W, et al. Thunderstorm feature dataset and characteristics of thunderstorm activities in China. J Appl Meteor Sci, 2021, 32(3): 358-369. doi: 10.11898/1001-7313.20210308 [4] 田野, 姚雯, 尹佳莉, 等. 不同闪电跃增算法在北京地区应用效果对比. 应用气象学报, 2021, 32(2): 217-232. doi: 10.11898/1001-7313.20210207Tian Y, Yao W, Yin J L, et al. Comparison of the performance of different lightning jump algorithms in Beijing. J Appl Meteor Sci, 2021, 32(2): 217-232. doi: 10.11898/1001-7313.20210207 [5] Wang D, Takagi N, Watanabe T, et al. Observed characteristics of upward leaders that are initiated from a windmill and its lightning protection tower. Geophys Res Lett, 2008, 35(2): 196-199. [6] Lu W, Wang D, Zhang Y, et al. Two associated upward lightning flashes that produced opposite polarity electric field changes. Geophys Res Lett, 2009, 36(5): 277-291. [7] Wang Z, Qie X, Jiang R, et al. High-speed video observation of stepwise propagation of a natural upward positive leader. J Geophys Res Atmos, 2016, 121(24): 14307-14315. [8] Warner T A, Cummins K L, Orville R E. Upward lightning observations from towers in Rapid City, South Dakota and comparison with national lightning detection network data, 2004-2010. J Geophys Res Atmos, 2012, 117(D19). DOI: 10.1029/2012JD018346. [9] Saba M M, Schumann C, Warner T A, et al. Upward lightning flashes characteristics from high-speed videos. J Geophys Res Atmos, 2016, 121(14): 8493-8505. doi: 10.1002/2016JD025137 [10] Warner T A, Saba M, Rudge S, et al. Lightning-triggered Upward Lightning from Towers in Rapid City, South Dakota. International Lightning Detection Conference, 2012. [11] 雷艺楠, 谭涌波, 余骏皓, 等. 高矮建筑物多上行先导连接过程的数值模拟. 应用气象学报, 2022, 33(1): 80-91. doi: 10.11898/1001-7313.20220107Lei Y N, Tan Y B, Yu J H, et al. Numerical simulation on multiple upward leader attachment process of tall and low buildings. J Appl Meteor Sci, 2022, 33(1): 80-91. doi: 10.11898/1001-7313.20220107 [12] Yuan S, Jiang R, Qie X S, et al. Characteristics of upward lightning on the Beijing 325 m meteorology tower and corresponding thunderstorm conditions: Upward lightning & thunderstorm. J Geophys Res Atmos, 2017, 122(22): 12093-12105. [13] Heidler F, Manhardt M, Stimper K. Upward positive lightning measured at the Peissenberg Tower, Germany. IEEE Transactions on Electromagnetic Compatibility, 2015, 57(1): 102-111. doi: 10.1109/TEMC.2014.2359584 [14] Diendorfer G, Pichler H, Mair M. Some parameters of negative upward-initiated lightning to the Gaisberg Tower(2000-2007). IEEE Trans Electromagn Compat, 2009, 51(3): 443-452. doi: 10.1109/TEMC.2009.2021616 [15] Shindo T, Tajima A, Motoyama H, et al. Meteorological conditions and occurrence of upward lightning at high structures. IEEJ Transactions on Power and Energy, 2015, 135(6): 417-418. doi: 10.1541/ieejpes.135.417 [16] Schumann C, Saba M, Warner T, et al. On the triggering mechanisms of upward lightning. Scientific Reports, 2019, 9(1). DOI: 10.1038/s41598-019-46122-x. [17] Saba M, Paiva A, Concollato L C, et al. Optical observation of needles in upward lightning flashes. Scientific Reports, 2020, 10(1). DOI: 10.1038/s41598-020-74597-6. [18] Sunjerga A, Rubinstein M, Azadifar M, et al. Bidirectional recoil leaders in upward lightning flashes observed at the Säntis Tower. J Geophys Res Atmos, 2021, 126(18). DOI: 10.1029/2021JD035238. [19] Yuan S, Qie X, Jiang R, et al. In-cloud discharge of positive cloud-to-ground lightning and its influence on the initiation of tower-initiated upward lightning. J Geophys Res Atmos, 2021, 126(24). DOI: 10.1029/2021JD035600. [20] 王艺儒, 谭涌波, 郑天雪, 等. 利于上行负地闪始发的电荷区参数数值模拟. 应用气象学报, 2020, 31(2): 175-184. doi: 10.11898/1001-7313.20200205Wang Y R, Tan Y B, Zheng T X, et al. Numerical simulation of main negative charge area parameters for upward negative cloud-to-ground lightning. J Appl Meteor Sci, 2020, 31(2): 175-184. doi: 10.11898/1001-7313.20200205 [21] 齐奇, 吕伟涛, 武斌, 等. 广州两座高建筑物上闪击距离的二维光学观测. 应用气象学报, 2020, 31(2): 156-164. doi: 10.11898/1001-7313.20200203Qi Q, Lü W T, Wu B, et al. Two-dimensional optical observation of striking distance of lightning flashes to two buildings in Guangzhou. J Appl Meteor Sci, 2020, 31(2): 156-164. doi: 10.11898/1001-7313.20200203 [22] 武斌, 吕伟涛, 齐奇, 等. 双向先导正端突然延展现象的高速摄像观测. 应用气象学报, 2020, 31(2): 146-155. doi: 10.11898/1001-7313.20200202Wu B, Lü W T, Qi Q, et al. High-speed video observations on abrupt elongations of the positive end of bidirectional leader. J Appl Meteor Sci, 2020, 31(2): 146-155. doi: 10.11898/1001-7313.20200202 [23] 李俊, 张义军, 吕伟涛, 等. 一次多回击自然闪电的高速摄像观测. 应用气象学报, 2008, 19(4): 401-411. http://qikan.camscma.cn/article/id/20080403Li J, Zhang Y J, Lü W T, et al. Observation of a natural cloud-to-ground lightning with multiple return strokes. J Appl Meteor Sci, 2008, 19(4): 401-411. http://qikan.camscma.cn/article/id/20080403 [24] Wu B, Lyu W T, Qi Q, et al. High-speed video observations of needles in a positive cloud-to-ground lightning flash. Geophys Res Lett, 2022, 49(2). DOI: 10.1029/2021GL096546. [25] Qi Q, Lyu W T, Wu B, et al. Two-dimensional striking distance of lightning flashes to a cluster of tall buildings in Guangzhou. J Geophys Res Atmos, 2021, 126(22). DOI: 10.1029/2021JD034613. [26] Berger K. Novel observations on lightning discharges: Results of research on Mount San Salvatore. Journal of the Franklin Institute, 1967, 283(6): 478-525. doi: 10.1016/0016-0032(67)90598-4 [27] Chang J S, Beuthe T G, Hu G G, et al. Thundercloud electric field measurement in the 553-m CN Tower during 1978-1983. J Geophys Res Atmos, 1985, 90(D4): 6087-6090. [28] Manhardt M, Heidler F, Stimper K. The Electric Field of Negative Upward Lightning Strikes at the Peissenberg Tower, Germany//International Conference on Lightning Protection, 2012. [29] Jiang R, Qie X, Wu Z, et al. Characteristics of upward lightning from a 325 m tall meteorology tower. Atmos Res, 2014, 149(6): 111-119. [30] Gorin B N. Measurements of lightning currents at the Ostankino tower. Elektrich, 1984, 8: 64-65. [31] Suzuki T. Long term observation of winter lightning on Japan Sea Coast. Res Lett Atmos Electr, 1992, 12: 53-56. [32] Lu W T, Gao Y, Qi Q, et al. Three-dimensional propagation characteristics of the leaders in the attachment process of a downward negative lightning flash. J Atmos Sol Terr Phys, 2015, 136: 23-30. [33] Qi Q, Lu W T, Wu B, et al. Three-dimensional optical observations of an upward lightning triggered by positive cloud-to-ground lightning. Atmos Res, 2018, 214: 275-283. [34] Markus H. 3D Reconstruction and Geographical Referencing of Lightning Discharges. Graz: Graz University of Technology, 2008: 1-120. [35] Liu Y C. A Feasibility Study on the Three-dimensional Reconstruction of High Voltage and Lightning Discharge Channels Using Digital Images. Johannesburg: University of the Witwatersrand, 2012: 1-169. [36] Gao Y, Lu W T, Ma Y, et al. Three-dimensional propagation characteristics of the upward connecting leaders in six negative tall-object flashes in Guangzhou. Atmos Res, 2014, 149: 193-203. [37] 王智敏, 吕伟涛, 陈绿文, 等. 2011—2012年广州高建筑物雷电磁场特征统计. 应用气象学报, 2015, 26(1): 87-94. doi: 10.11898/1001-7313.20150109Wang Z M, Lü W T, Chen L W, et al. Statistical characteristics of magnetic field produced by tall-object lightning in Guangzhou during 2011-2012. J Appl Meteor Sci, 2015, 26(1): 87-94. doi: 10.11898/1001-7313.20150109 [38] 张义军, 吕伟涛, 陈绍东, 等. 广东野外雷电综合观测试验十年进展. 气象学报, 2016, 74(5): 655-671. https://www.cnki.com.cn/Article/CJFDTOTAL-QXXB201605001.htmZhang Y J, Lü W T, Chen S D, et al. A review of lightning observation experiments during the last ten years in Guangdong. Acta Meteor Sinica, 2016, 74(5): 655-671. https://www.cnki.com.cn/Article/CJFDTOTAL-QXXB201605001.htm [39] 吕伟涛, 陈绿文, 马颖, 等. 广州高建筑物雷电观测与研究10年进展. 应用气象学报, 2020, 31(2): 129-145. doi: 10.11898/1001-7313.20200201Lü W T, Chen L W, Ma Y, et al. Advances of observation and study on tall-object lightning in Guangzhou over the last decade. J Appl Meteor Sci, 2020, 31(2): 129-145. doi: 10.11898/1001-7313.20200201 [40] 吕伟涛, 张阳, 马颖, 等. 全视野闪电事件观测系统及方法. 发明专利, 2013: 2011100662855.Lü W T, Zhang Y, Ma Y, et al. Total-sky Lightning Channel Imager and Method. Patent, 2013: 2011100662855. [41] Lü W T, Ma Y, Zhang Y, et al. Total-sky Lightning Event Observation System and Method. US Patent, 2014: US 8902312 B2. [42] Shi D, Zheng D, Zhang Y, et al. Low-frequency E-field Detection Array(LFEDA)-Construction and preliminary results. Sci China Earth Sci, 2017, 60(10): 1896-1908. [43] 陈绿文, 吕伟涛, 张义军, 等. 粤港澳闪电定位系统对高建筑物雷电的探测. 应用气象学报, 2020, 31(2): 165-174. doi: 10.11898/1001-7313.20200204Chen L W, Lü W T, Zhang Y J, et al. Detection results of Guangdong-Hongkong-Macao lightning location system for tall-object lightning. J Appl Meteor Sci, 2020, 31(2): 165-174. doi: 10.11898/1001-7313.20200204 [44] 张悦, 吕伟涛, 陈绿文, 等. 基于人工引雷的粤港澳闪电定位系统探测性能评估. 应用气象学报, 2022, 33(3): 329-340. https://www.cnki.com.cn/Article/CJFDTOTAL-YYQX202203005.htmZhang Y, Lü W T, Chen L W, et al. Evaluation of GHMLLS performance characteristics based on observations of artificially triggered lightning. J Appl Meteor Sci, 2022, 33(3): 329-340. https://www.cnki.com.cn/Article/CJFDTOTAL-YYQX202203005.htm [45] 武斌, 吕伟涛, 齐奇, 等. 一次正地闪触发两个并发上行闪电的光电观测. 应用气象学报, 2019, 30(3): 257-266. doi: 10.11898/1001-7313.20190301Wu B, Lü W T, Qi Q, et al. Optical and electric field observations of two concurrent upward flashes triggered by a positive cloud-to-ground flash. J Appl Meteor Sci, 2019, 30(3): 257-266. doi: 10.11898/1001-7313.20190301 [46] 高彦. 闪电连接过程中先导三维发展特征的分析. 北京: 中国气象科学研究院, 2014.Gao Y. The Three-dimensional Propagation Characteristics of Flash Leaders in the Attachment Process. Beijing: Chinese Academy of Meteorological Sciences, 2014.