DOI: 10.1002/2013JD020854
论文题名: On the percentage of lightning flashes that begin with initial breakdown pulses
作者: Marshall T. ; Schulz W. ; Karunarathna N. ; Karunarathne S. ; Stolzenburg M. ; Vergeiner C. ; Warner T.
刊名: Journal of Geophysical Research Atmospheres
ISSN: 21698996
出版年: 2014
卷: 119, 期: 2 起始页码: 445
结束页码: 460
语种: 英语
英文关键词: initial breakdown
; lightning
Scopus关键词: Electric fields
; Sensors
; Amplitude ratios
; Electric field change
; Higher latitudes
; initial breakdown
; Initial breakdown pulse
; Lightning flashes
; Sensor noise level
; South dakotas
; Lightning
; amplitude
; atmospheric electricity
; latitude
; lightning
; noise
; Austria
; Florida [United States]
; South Dakota
; United States
英文摘要: The initial breakdown (IB) stage of lightning flashes typically occurs in the first 20 ms of a flash and includes a series of IB pulses often detected with electric field change sensors. There is disagreement about the percentage of negative cloud-to-ground (CG) flashes that begin with IB pulses. This study includes new data on IB pulses in 198 CG flashes in Austria (latitude ~48ËšN), Florida, USA (~29ËšN) and South Dakota, USA (~44ËšN) with, respectively, 100%, 100%, and 95% of the flashes having IB pulses. The data indicate that the amplitude of the largest IB pulse, range normalized to 100 km, is often weak, < 0.5 V m-1, with the lower latitude having a greater percentage (36%) of these weak maximum IB pulses than the higher latitude (11%). Since sensor noise levels are often larger than this value, detection of smaller amplitude IB pulses may be difficult. A similar result is seen in the amplitude ratio of the largest IB pulse to the first return stroke: at the lower latitude, 50% of flashes had a ratio < 0.1 versus 8% of flashes at the higher latitude. However, comparisons of the amplitude ratios from Austria (~48Ëš) and South Dakota (~44Ëš) do not support a simple latitude dependence. The data also show that 5-10% of IB pulses occur more than 100 ms before the first return stroke. These findings may explain why some previous studies found percentages <100%. Overall, the results indicate that all negative CG flashes probably begin with IB pulses. Key Points 198 negative CG flashes from 3 latitudes begin with initial breakdown pulses Amplitudes of the largest IBP per flash (range-normalized) are 0.03 to 14 V/m Time between largest IBP and first return stroke is 0.7-504 ms in 198 flashes ©2013. American Geophysical Union. All Rights Reserved. 资助项目: AGS-1110030
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资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/63063
Appears in Collections: 影响、适应和脆弱性 气候减缓与适应
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作者单位: Department of Physics and Astronomy, University of Mississippi, University MS, United States; Austrian Lightning Detection and Information System (ALDIS), Austrian Electrotechnical Association (OVE), Vienna, Austria; Institute of High Voltage Engineering and System Management, Graz University of Technology, Graz, Austria; Department of Atmospheric Sciences, South Dakota School of Mines and Technology, Rapid City SD, United States
Recommended Citation:
Marshall T.,Schulz W.,Karunarathna N.,et al. On the percentage of lightning flashes that begin with initial breakdown pulses[J]. Journal of Geophysical Research Atmospheres,2014-01-01,119(2)