气候变化领域集成服务门户(CCPortal): Compact Lightning Strokes in Winter Thunderstorms

CCPortal

DOI	10.1029/2021JD034932
	Compact Lightning Strokes in Winter Thunderstorms
	Wu T.; Wang D.; Takagi N.
发表日期	2021
ISSN	2169-897X
卷号	126 期号:15
英文摘要	With the observation of a 14-site Fast Antenna Lightning Mapping Array in the Hokuriku region of Japan, we identified a special type of lightning stroke called “compact stroke” in winter thunderstorms. A compact stroke starts with a fast downward negative leader followed by a “compact return stroke.” Compact strokes have the following characteristics that are not seen in normal lightning strokes: (a) Durations of preceding discharges (defined as the time difference between the return stroke and the start of the flash) are generally smaller than 200 μs. (b) Most compact strokes are inferred to be produced in small gaps between mountain tops and negative charge regions in winter thunderstorms. (c) Channel lengths of compact strokes are estimated to be shorter than 600 m with an average of about 300 m. (d) Characteristics of electric field change waveforms of compact return strokes are closely related with durations of preceding discharges. (e) Peak currents of compact return strokes increase with increasing channel lengths. It seems that elevations of mountain surfaces where compact strokes occur are comparable to the altitude of the lower positive charge region, so we speculate that the mountain surface and the near-surface space carry positive charges when a storm is overhead and are virtually the lower positive charge region of a normal tripole structure. As a result, compact strokes are confined between the main negative and lower positive charge regions, and small pulses with short durations preceding compact return strokes are produced by downward negative leaders corresponding to the preliminary breakdown stage. © 2021. American Geophysical Union. All Rights Reserved.
英文关键词	return stroke; winter lightning
来源期刊	Journal of Geophysical Research: Atmospheres
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/237085
作者单位	Department of Electrical, Electronic and Computer Engineering, Gifu University, Gifu, Japan
推荐引用方式 GB/T 7714	Wu T.,Wang D.,Takagi N.. Compact Lightning Strokes in Winter Thunderstorms[J],2021,126(15).
APA	Wu T.,Wang D.,&Takagi N..(2021).Compact Lightning Strokes in Winter Thunderstorms.Journal of Geophysical Research: Atmospheres,126(15).
MLA	Wu T.,et al."Compact Lightning Strokes in Winter Thunderstorms".Journal of Geophysical Research: Atmospheres 126.15(2021).