Chemical Activity of Low Altitude (50 km) Sprite Streamers

Abstract

A three‐stage simulation is used to explore the chemical influence of low altitude (50 km) sprite streamers on the atmosphere, including the chemical trail after the streamer has faded away. In the first stage (streamer phase) a 2D electrodynamical streamer model quantifies the generation of NOx and N2O, and the removal of ozone (O3) by a downward propagating streamer during Δtstreamer = 80 μs. This streamer propagation leads to a distinctive region in the streamer channel, the glow, where the electric field is enhanced. In the second stage (glow phase), the computed densities of the first stage are used as initial conditions for a 0D model to study the chemical evolution of the streamer channel, where we assume a remanent field of 100 Td for the glow and 0 Td elsewhere. This stage lasts Δtglow = 85 μs, the typical glow lifetime at 50 km. Finally, in the third stage (post‐streamer phase), we use the same 0D model, switch off the field in the glow region and let the whole streamer wake evolve roughly 100 s (100 s − Δtglow). Results show a key species such as O3 is mainly depleted during the streamer phase while NOx and N2O are predominantly produced during the same phase. We also compute the local increase of NO2 by sprite streamers at ∼50 km and find out that it could account for the measurable NO2 anomaly over thunderstorms reported from satellite‐based measurements.

Associative electron detachment in sprites

“…One notable benefit arising from the discovery of sprites (Franz et al, 1990) has been a renewed interest in the chemistry of the upper mesosphere, in particular on the reaction mechanisms induced by free, super-thermal electrons as present in sprites, where they are accelerated by intense electric fields. Several questions motivate this interest: for example there is the question of whether sprites have global, regional, or local effects on the composition of the atmosphere (Sentman et al, 2008;Arnone et al, 2008;Gordillo-Vázquez & Pérez-Invernón, 2021;Malagón-Romero et al, 2023). Understanding the spectra of sprites (Gordillo-Vázquez et al, 2012;Passas et al, 2016) is another motivation, particularly relevant in the context of space-based detection of sprites (Chanrion et al, 2019) and discrimination from other events such as Blue Luminous Events (BLUEs) in thundercloud tops (Chanrion et al, 2017;Soler et al, 2020).…”

Associative Electron Detachment in Sprites

“…One notable benefit arising from the discovery of sprites (Franz et al., 1990) has been a renewed interest in the chemistry of the upper mesosphere, in particular on the reaction mechanisms induced by free, super‐thermal electrons as present in sprites, where they are accelerated by intense electric fields. Several questions motivate this interest: for example, there is the question of whether sprites have global, regional, or local effects on the composition of the atmosphere (Arnone et al., 2008; Gordillo‐Vázquez & Pérez‐Invernón, 2021; Malagón‐Romero et al., 2023; Sentman et al., 2008). Understanding the spectra of sprites (Gordillo‐Vázquez et al., 2012; Passas et al., 2016) is another motivation, particularly relevant in the context of space‐based detection of sprites (Chanrion et al., 2019) and discrimination from other events such as Blue Luminous Events (BLUEs) in thundercloud tops (Chanrion et al., 2017; Soler et al., 2020).…”

Capturing photoionization shadows in streamer simulations using the discrete ordinates method

“…Streamers are precursors to many discharge phenomena such as sparks, lighting leaders, and discharges in high altitudes such as the sprites and blue jets [4]. Streamer discharges produce charged species in the gas, and for laboratory discharges also on surfaces, initiate unique chemical reactions thanks to the excited atomic and molecular states created [5][6][7][8][9][10][11][12], and are even able to induce gas flow by electrohydrodynamic forces [13]. These phenomena lead to numerous technical applications [14][15][16].…”