气候变化领域集成服务门户(CCPortal): Characterizing three types of negative narrow bipolar events in thunderstorms

CCPortal

DOI	10.1016/j.atmosres.2019.05.013
	Characterizing three types of negative narrow bipolar events in thunderstorms
	Bandara S.; Marshall T.; Karunarathne S.; Karunarathne N.; Siedlecki R.; Stolzenburg M.
发表日期	2019
ISSN	0169-8095
起始页码	263
结束页码	279
卷号	227
英文摘要	Data from fast antennas (FAs)with bandwidth of 16 Hz–2.5 MHz and VHF power sensors (Log-RF)with bandwidth of 186–192 MHz are used to examine negative narrow bipolar events, or NNBEs. The main focus is on low-altitude (<8.0 km)NNBEs that initiate negative cloud-to-ground (-CG)flashes; very few low-altitude NNBEs have been studied previously. For comparison, 24 high-altitude (>8.0 km)NNBEs are also examined. The low-altitude NNBEs are found to have two types called NNBE(L)and NNBE(H). NNBE(L)s have a bipolar FA waveform typical of NBEs while NNBE(H)s have a unipolar FA waveform. It is hypothesized that NNBE(H)s may be weak versions of NNBE(L)s in which the second, overshoot part of the bipolar waveform is too weak to detect amid the FA sensor noise. Together the 33 NNBE(L)s and NNBE(H)s occurred at an average altitude of 6.2 km (range 4.6–7.8 km), had average range-normalized (to 100 km)amplitude of 0.4 V/m (range 0.06–1.5 V/m), and had average VHF power of 130 W (range 1–1300 W). These low-altitude NNBE properties are substantially smaller and weaker than the same properties of the high-altitude NNBEs and of positive NBEs that initiate intracloud (IC)flashes; these analyses indicate that -CG flashes are easier to initiate than IC flashes. Visual inspection of the FA and Log-RF data of 868 -CG flashes showed that only 33 flashes (4%)were preceded by either an NNBE(L)or NNBE(H), so 96% of the -CG flashes investigated probably did not begin with an NNBE. © 2019 The Authors
英文关键词	Initial breakdown pulses; Lightning; Lightning initiation; Narrow bipolar event
语种	英语
scopus关键词	Bandwidth; Initial breakdown pulse; Lightning initiation; Low altitudes; Narrow bipolar events; Power sensor; Sensor noise; Visual inspection; Wave forms; Lightning; altitude; cloud to ground lightning; comparative study; sensor; thunderstorm; waveform analysis
来源期刊	Atmospheric Research
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/162003
作者单位	Department of Physics & Astronomy, University of Mississippi, University, MS 38677, United States
推荐引用方式 GB/T 7714	Bandara S.,Marshall T.,Karunarathne S.,et al. Characterizing three types of negative narrow bipolar events in thunderstorms[J],2019,227.
APA	Bandara S.,Marshall T.,Karunarathne S.,Karunarathne N.,Siedlecki R.,&Stolzenburg M..(2019).Characterizing three types of negative narrow bipolar events in thunderstorms.Atmospheric Research,227.
MLA	Bandara S.,et al."Characterizing three types of negative narrow bipolar events in thunderstorms".Atmospheric Research 227(2019).