气候变化领域集成服务门户(CCPortal): Lightning Interferometry Uncertainty, Beam Steering Interferometry, and Evidence of Lightning Being Ignited by a Cosmic Ray Shower

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DOI	10.1029/2019JD032273
	Lightning Interferometry Uncertainty, Beam Steering Interferometry, and Evidence of Lightning Being Ignited by a Cosmic Ray Shower
	Shao X.-M.; Ho C.; Bowers G.; Blaine W.; Dingus B.
发表日期	2020
ISSN	2169897X
卷号	125 期号:19
英文摘要	We present an uncertainty analysis on correlation-based time delay estimate, the basis for broadband lightning interferometry. A normal interferometry would yield much higher uncertainties than the theoretically predicted lower bound due to finite correlation window lengths. However, if the signals are aligned in time, the uncertainties approach the lower bound and can be used to indicate the interferometric uncertainties. Based on this, we introduce a beam steering interferometry technique. It first estimates a direction centroid for the lightning sources with a normal interferometry and computes the time delays among the signals. It then shifts the raw data with the time delays to align the signals roughly in time and reprocess the aligned signals. It finally pushes the reprocessed results to their correct positions, based on the time delays estimated in the first step. We apply this technique on a fast positive breakdown (FPB) process that started a normal intracloud lightning. The FPB process is shown to have a much more complex structure and development than a normal interferometry would provide. More importantly, from both interferometric and polarization analyses, the FPB appears to be ignited by a cosmic ray shower (CRS). We estimate the radio frequency strength and frequency content related to a presumed CRS in a thunderstorm electric field and find that they are in agreement with the observations. We examine the electric field effect of the CRS front and find that it could raise the field above the threshold for positive breakdown and is capable of igniting the FPB (and the lightning). © 2020. The Authors.
英文关键词	fast positive breakdown; interferometry; lightning initiation; uncertainty analysis
语种	英语
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/185714
作者单位	Los Alamos National Laboratory, Los Alamos, NM, United States
推荐引用方式 GB/T 7714	Shao X.-M.,Ho C.,Bowers G.,et al. Lightning Interferometry Uncertainty, Beam Steering Interferometry, and Evidence of Lightning Being Ignited by a Cosmic Ray Shower[J],2020,125(19).
APA	Shao X.-M.,Ho C.,Bowers G.,Blaine W.,&Dingus B..(2020).Lightning Interferometry Uncertainty, Beam Steering Interferometry, and Evidence of Lightning Being Ignited by a Cosmic Ray Shower.Journal of Geophysical Research: Atmospheres,125(19).
MLA	Shao X.-M.,et al."Lightning Interferometry Uncertainty, Beam Steering Interferometry, and Evidence of Lightning Being Ignited by a Cosmic Ray Shower".Journal of Geophysical Research: Atmospheres 125.19(2020).