Secondary Fast Breakdown in Narrow Bipolar Events

Abstract

The physical mechanism of Narrow bipolar events (NBEs) has been studied for decades but it still holds many mysteries. Recent observations indicate that the fast breakdown discharges that produce NBEs sometimes contain a secondary fast breakdown that propagates back in the opposite direction but this has not been fully addressed so far in electromagnetic models. In this study, we investigate fast breakdown using different approaches that employ a Modified Transmission Line with Exponential decay (MTLE) model and propose a new model, named “rebounding MTLE model,” which reproduces the secondary fast breakdown current in NBEs. The model provides new insights into the physics of the fast breakdown mechanism.

Analysis of Narrow Bipolar Events Using Mode Decomposition Methods

“…Our results suggest that the precursor fast breakdown event leaves behind a resonant cavity that produces strong half-wavelength radiation (standing wave with d = λ/2, i.e., the fundamental mode). The INTF shows downward propagation followed by an upward rebound, as discussed by Attanasio et al (2021) and Li et al (2022). After that, there is no clear additional source motion.…”

Different Types of Corona Discharges Associated With High‐Altitude Positive Narrow Bipolar Events Nearby Cloud Top

“…Previous studies indicate that both positive and negative streamers could be involved in the fast breakdowns of CIDs emitting NBEs and overlap within a significative volume (Huang et al., 2021; Li, Luque, Gordillo‐Vázquez et al., 2022; Lyu et al., 2019; Rison et al., 2016; Tilles et al., 2019). The microsecond‐scale oscillations of NBEs are observed in both single‐ and multi‐pulse BLUEs, which suggests that the BLUEs might be produced by the fast breakdowns consisting of both positive and negative streamers.…”

“…Some NBEs, correlated with both single‐and multi‐pulse BLUEs, included microsecond‐scale oscillations inside their waveforms. Recent studies indicate that the fast breakdowns of NBEs sometimes contain secondary fast breakdowns along the previous path (Attanasio et al., 2021; Li, Luque, Gordillo‐Vázquez et al., 2022; Rison et al., 2016; Tilles et al., 2019). Most recent observations from the LOw Frequency ARray (LOFAR) also indicate that multiple, spatially distributed corona bursts can occur in lightning processes with a timescale of 10 µs (N. Liu et al., 2022).…”

Observation of Blue Corona Discharges and Cloud Microphysics in the Top of Thunderstorm Cells in Cyclone Fani

“…Recent studies have linked blue corona discharges to short‐duration (10–20 µs) bipolar pulses with strong Very High Frequency radiation, called Narrow Bipolar Events (NBEs) (Chou et al., 2018; Li et al., 2021, 2022b; F. Liu et al., 2018, 2021a, 2021b; Smith et al., 1999, 2004; Soler et al., 2020; Wu et al., 2012). NBEs are thought to be produced by localized and fast propagating streamers, known as fast breakdown (Li et al., 2022a; N. Liu et al., 2019; Rison et al., 2016; Tilles et al., 2019). They are likely to occur independently from other lightning discharges within tens of milliseconds or at the onset of lightning leader formation (Kostinskiy et al., 2020; López et al., 2022; Lyu et al., 2019; Marshall et al., 2019; Rison et al., 2016).…”