Some properties of negative cloud‐to‐ground lightning flashes versus stroke order
Some properties of negative cloud‐to‐ground lightning flashes versus stroke order
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DOI：
10.1029/jd095id05p05447
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发表时间：
1990-04
影响因子：
--
通讯作者：
V. Rakov;M. Uman
中科院分区：
文献类型：
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作者：
V. Rakov;M. Uman
回击的初始电场峰值归一化为100公里，在地面上创建一个新的终止的概率，和一个飞镖步领导者的发生概率后，间隔100毫秒或更少的中风已被确定为一个功能的中风顺序从同时电场和电视记录的76个负的云到地闪附近的坦帕，佛罗里达。根据电视记录，50%的闪电在地面上有多次终止（在不同的雷暴天，从29%到69%）。对于所有的闪光，最小的初始电场峰值归一化为100公里的第一次中风被发现是2.2 V/m和后续中风0.25 V/m。第二、第三和第四次共155次电击的几何平均初始电场峰值比第5至18次共115次电击的几何平均初始电场峰值大1.4倍，差异在0.005显著性水平上具有统计学显著性。几何平均初始电场峰值为63第一次中风多冲程闪光被发现是1.3倍以上的13中风单冲程闪光。观察到在新墨西哥州由中风降低的电荷表现出类似于上述在佛罗里达的初始电场峰值的行为。在地面上产生新的终止的后续笔划显示出比遵循与前一笔划相同的通道的笔划更高的初始电场峰值，但低于闪光中的第一笔划。第二击显示了在地面上产生新的终止（0.37）和在100 ms或更短的击间间隔之后沿着前一击的通道产生飞镖阶梯状先导（沿着）的最大概率（0.36）。115次5级以上的中风中没有一次在地面上产生新的终止，尽管其中22次的前一次中风间隔为101至253 ms，并且不包含长时间的持续电流。所提出的结果和其他相关数据在文献中是一致的，提出的假设，连续中风提供累积调节的闪电通道。
The return stroke initial electric field peak normalized to 100 km, the probability of creating a new termination on ground, and the probability of occurrence of a dart-stepped leader after an interstroke interval of 100 ms or less have been determined as a function of stroke order from simultaneous electric field and TV records of 76 negative cloud-to-ground flashes near Tampa, Florida. Fifty percent of the flashes showed multiple terminations on the ground as inferred from TV records (from 29 to 69 percent for separate thunderstorm days). For all flashes, the minimum initial electric field peak normalized to 100 km for first strokes was found to be 2.2 V/m and for subsequent strokes 0.25 V/m. The geometric mean initial electric field peak for 155 second, third and fourth strokes taken together was found to be 1.4 times larger than for 115 strokes of order 5 through 18, with the difference being statistically significant at the 0.005 significance level. The geometric mean initial electric field peak for 63 first strokes in multiple-stroke flashes was found to be 1.3 times larger than for 13 strokes in single-stroke flashes. The charge lowered by strokes in New Mexico was observed to exhibit behavior similar to that of the initial electric field peak in Florida described above. Subsequent strokes creating a new termination on ground showed a higher initial electric field peak than strokes following the same channel as the preceding stroke, but lower than for first strokes in a flash. Second strokes showed the maximum probability of both creating a new termination on ground (0.37) and producing a dart-stepped leader along the channel of the previous stroke after an interstroke interval of 100 ms or less (0.36). None of the 115 strokes of order 5 and higher created a new termination on ground in spite of the fact that previous interstroke intervals for 22 of them were from 101 to 253 ms and did not contain long continuing current. The results presented and other relevant data available in the literature are consistent with the proposed hypothesis that successive strokes provide cumulative conditioning of the lightning channel.