Potential use of space-based lightning detection in electric power systems

Lightning flashes are an important source of wildfires worldwide, contributing to the emission of trace gases to the atmosphere. Based on experiments and field observations, continuing currents in lightning have since a long time been proposed to play a significant role in the ignition of wildfires. However, simultaneous detections of optical and radio signals from fire‐igniting lightning confirming the role of continuing currents in igniting wildfires are rare. In this work, we first analyze the optical signal of the lightning‐ignited wildfires reported by the Geostationary Lightning Mapper over the Contiguous United States (CONUS) during the summer of 2018, and we then analyze the optical and the Extremely Low Frequency signal of a confirmed fire‐igniting lightning flash in the Swiss Alps. Despite data uncertainties, we found that the probability of ignition of a lightning flash with Continuing Current (CC) lasting more than 10 ms is higher than that of cloud‐to‐ground lightning in CONUS. Finally, we confirm the existence of a long CC (lasting about 400 ms) associated with a long‐lasting optical signal (lasting between 2 and 4 s) of a video‐recorded fire‐igniting lightning flash.

Section: Methodsmentioning

confidence: 88%

On the Role of Continuing Currents in Lightning‐Induced Fire Ignition

Pérez‐Invernón,

Moris,

Gordillo‐Vázquez

et al. 2023

“…In further research, the method presented by Montanyà et al. (2022) employing space‐based optical detection to identify flashes that potentially initiate upward lightning from tall structures could be applied to find RLS related to tall towers.…”

Section: Discussionmentioning

confidence: 99%

“…That means the number of RLS related to tall towers might also be underestimated in the same way as in Catalonia (Spain), due to the undetectable low peak currents involved in lightning-triggered upward lightning flashes (or pulses). In further research, the method presented by Montanyà et al (2022) employing space-based optical detection to identify flashes that potentially initiate upward lightning from tall structures could be applied to find RLS related to tall towers.…”

Section: Type Of Lightning At Rlsmentioning

confidence: 99%

Recurrent Lightning Spots: Where Lightning Strikes More Than Twice

Sola,

López,

Montanyà

et al. 2024

Self Cite

The expression “lightning never strikes twice” is questioned in this paper because, among the randomness of lightning impacts, some spots are hit even more than twice year after year. This article introduces the recurrent lightning spots (RLS) concept, which are locations periodically impacted by cloud‐to‐ground lightning every consecutive year over a certain period. RLS are investigated in two regimes, with markedly different lightning climatology but similar orography, for 10 consecutive years: Catalonia (North East of Spain, Europe) and Barrancabermeja (North Central Colombia, South America). Results revealed 148 and 916 RLS in Catalonia and Barrancabermeja, respectively. RLS in both regions are typically found to be related to tall structures, mountain peaks, and steep terrain. The method allowed us to identify those tall towers and orographic relief frequently affected by lightning that are not detected with the mere computation of the ground flash density. In the case of Catalonia, some RLS are found offshore. Besides the scientific interest in understanding lightning, the new concept of RLS provides additional and valuable information applicable to lightning protection engineering.

“…As an example, Fairman and Bitzer (2022) quantified the probability of detection by GLM in a 78% for the proposed model. Nevertheless, the interpretation of space‐based optical detections of flashes with long continuing currents is limited to only a few simultaneous optical observation studies from ground and from space (Fairman & Bitzer, 2022; Montanyà et al., 2022). In Figure 7 we provide an example of the measured 777 and 337 nm radiances during the continuing current phase, together with the brightness of the lightning channel from the high‐speed video, and the detections by GLM.…”

Section: Discussionmentioning

confidence: 99%

Ground‐Based Observations of 337 nm and 777 nm Optical Emissions Produced by Lightning

Roncancio,

Montanyà,

López

et al. 2024

Self Cite

Lightning flashes were observed in Barrancabermeja (Colombia) by two photometers centered at 337 and 777 nm wavelengths, a high‐speed camera, and the Colombia Lightning Mapping Array. Both optical and VHF radio emissions of different lightning processes are investigated. Flash initiations by upward in‐cloud breakdown present a first short optical pulse followed by a period of ∼1 kHz breakdown propagation. The ratio remains at unity or below, associated with the transition to negative horizontal leader propagation. In flash initiations by a fast‐stepped negative downward leader to ground, a dominance of the 337 nm radiance is found. Observations of downward leaders before ground strokes reveal that the luminosity measured by the photometers is dominated most of the time by the light coming from the cloud and not from the visible leader channels. One case of a visible cloud‐to‐ground channel with positive continuing current shows a high similarity in the evolution of the luminosity along the channel, 777 nm radiance, and the energy detected by the Geostationary Lightning Mapper from space. Finally, two types of recoil leaders have been observed: connecting and non‐connecting. Whereas the measured 777 nm peak radiance is similar in both types of recoil leaders, connecting recoil leaders present about seven times higher 337 nm peak radiance. Our observations generally show agreement between the VHF power and optical emissions.