Upward Lightning Observed by LF Broadband Interferometer

Takayanagi, Yuji; Akita, Manabu; Nakamura, Yoshitaka; Yoshida, Shigeaki; Morimoto, Takeshi; Ushio, Tomoo; Kawasaki, Zen‐Ichiro; Wang, Daohong; Takagi, Nobuyuki; Sakurano, Hitoshi; Kubouchi, Yoshiyuki

doi:10.1541/ieejfms.133.132

Cited by 11 publications

(10 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Lightning activities in Kanazawa are monitored by a broadband low‐frequency (LF) lightning location network (Takayanagi et al, ; Wada et al, , ), hereafter called LF network. The LF network has six observation points along Toyama Bay and in Kanazawa, consisting of a flat plate antenna sensitive to the 0.8–500 kHz band.…”

Section: Instrumentsmentioning

confidence: 99%

High Peak‐Current Lightning Discharges Associated With Downward Terrestrial Gamma‐Ray Flashes

et al. 2020

View full text Add to dashboard Cite

During 2017–2018 winter operation of the Gamma‐Ray Observation of Winter Thunderclouds experiment in Japan, two downward terrestrial gamma‐ray flashes (TGFs) that triggered atmospheric photonuclear reactions were detected. They took place during winter thunderstorms on 5 December 2017 and 9 January 2018 at Kanazawa, Ishikawa Prefecture, Japan. Each event coincided with an intracloud/intercloud discharge, which had a negative‐polarity peak current higher than 150 kA. Their radio waveforms in the low‐frequency band are categorized as a distinct lightning type called “energetic in‐cloud pulse” (EIP). Negative‐polarity EIPs have been previously suggested to be highly associated with downward TGFs, and the present observations provide evidence of the correlation between them for the first time. Furthermore, both of the downward TGFs followed “gamma‐ray glows,” minute‐lasting high‐energy emissions from thunderclouds. It is suggested that the negative EIPs took place with downward propagating negative leaders or upward positive ones developed in highly electrified regions responsible for the gamma‐ray glows.

show abstract

Section: Instrumentsmentioning

confidence: 99%

High Peak‐Current Lightning Discharges Associated With Downward Terrestrial Gamma‐Ray Flashes

et al. 2020

View full text Add to dashboard Cite

show abstract

“…BOLT consists of four or more LF band sensors that receive electromagnetic waves associated with lightning discharges and locates LF radiation sources in 3D. Return strokes, K‐process, and positive and negative upward leaders initiated from a tall tower, and stepped leader processes were located by BOLT [ T. Takayanagi et al ., ; Y. Takayanagi et al ., ]. Observing NBE using BOLT in 2012, Wu et al .…”

Section: Introductionmentioning

confidence: 98%

Initial results of LF sensor network for lightning observation and characteristics of lightning emission in LF band

Yoshida

Ushio

et al. 2014

JGR Atmospheres

Self Cite

View full text Add to dashboard Cite

We have been developing an LF sensor network called Broadband Observation network forLightning and Thunderstorm (BOLT), to image the structure of lightning discharges in 3D using time of arrival (TOA) technique. This paper documents initial results and characteristics of BOLT source locations for further understanding of LF radiation associated with lightning. Theoretical reduced Chi-square distribution fitted to BOLT observation data indicates a root mean square (rms) timing error of about 200 ns for each sensor. Monte Carlo simulations of BOLT indicate that at an altitude of 5000 m the standard deviations for horizontal differences between a known source and a location that the BOLT algorithm produces are less than 200 m, and vertical differences are less than 400 m in most of the network. Furthermore, comparison of BOLT and VHF source locations arriving at the same site within 5 μs indicates that the average difference for elevation direction is 0.73°with a standard deviation of 3.64°, and that for the azimuth direction is 0.58°with a standard deviation of 1.98°. Lightning flash processes of intracloud (IC) and cloud-to-ground (CG) flashes, including preliminary breakdown pulses, negative leaders, breakdown in the negative charge region (NCR), and an attempted leader, are well imaged by BOLT. Normalized amplitudes in E-field change waveform of BOLT sources associated with negative leaders and breakdown occurred in the NCR do not have significant difference, implying that most BOLT sources in the NCR might be associated with negative recoil leaders.

show abstract

“…We also have had many experiments near the Japan Sea coast for winter lightning observation. During the winter of 2010–2011, we set up a small low frequency (LF) lightning location system comprising five stations [ Takayanagi et al ., ] in Hokuriku region and recorded a type of bipolar waveform that seemed not have been reported before. However, because the location network was too small, most of these discharges could not be accurately located.…”

Section: Introductionmentioning

confidence: 99%

Large bipolar lightning discharge events in winter thunderstorms in Japan

Yoshida

Ushio

et al. 2014

JGR Atmospheres

Self Cite

View full text Add to dashboard Cite

Using a low-frequency lightning location system comprising nine stations, we have observed and analyzed 374 large and bipolar electric field change waveforms that occurred during the winter of 2012-2013. Since the waveforms are different from those produced by any well-studied lightning discharge processes, we refer to these source discharge events using a new name: large bipolar events (LBEs). LBEs can be characterized by the following features: (1) All have the same polarity as negative return stroke. (2) All exhibit a single bipolar pulse with a pulse width around 15 μs and similar positive and negative cycles. (3) All are located on the land along the Japan Sea coast, indicating they are probably associated with high grounded objects. (4) Most LBEs produce very large electric field changes that are even larger than that of positive and negative return strokes. (5) Most LBEs are temporally isolated within several milliseconds but are frequently followed by intracloud discharges after tens of milliseconds. (6) Most LBEs produce a single well-distinguished ionospheric reflection pulse, and the time difference between LBE pulse and the corresponding reflection pulse can be used to calculate ionospheric reflection height. It is speculated that LBE is a type of powerful and transient lightning discharge event produced within a compact region of strong electric field formed when the negative charge layer in thunderclouds is very close to the top of a tall grounded object.

show abstract

Upward Lightning Observed by LF Broadband Interferometer

Cited by 11 publications

References 13 publications

High Peak‐Current Lightning Discharges Associated With Downward Terrestrial Gamma‐Ray Flashes

High Peak‐Current Lightning Discharges Associated With Downward Terrestrial Gamma‐Ray Flashes

Initial results of LF sensor network for lightning observation and characteristics of lightning emission in LF band

Large bipolar lightning discharge events in winter thunderstorms in Japan

Contact Info

Product

Resources

About