Estimating Precipitating Energy Flux, Average Energy, and Hall Auroral Conductance From THEMIS All-Sky-Imagers With Focus on Mesoscales

• DOI: 10.3389/fphy.2021.744298
• Publication Date: 2021-10-13T17:17:11Z
• Authors: Christine Gabrielse; Toshi Nishimura; Margaret Chen; James H. Hecht; Stephen R. Kaeppler; D. Megan Gillies; Ashton S. Reimer; Larry R. Lyons; Yue Deng; Eric Donovan; J. Scott Evans
• Keywords: Substorm; Energy flux

Recent attention has been given to mesoscale phenomena across geospace (∼10 s km 500 in the ionosphere or ∼0.5 R E several magnetosphere), as their contributions system global response are important yet remain uncharacterized mostly due limitations data resolution and coverage well computational power. As models improve, it becomes increasingly valuable advance understanding of role contributions—specifically, magnetosphere-ionosphere coupling. This paper describes a new method that utilizes 2D array Time History Events Macroscale Interactions during Substorms (THEMIS) white-light all-sky-imagers (ASI), conjunction with meridian scanning photometers, estimate auroral scale sizes intense precipitating energy fluxes associated Hall conductances. an example technique, we investigated precipitated flux average on mesoscales contrasted large-scales for two back-to-back substorms, finding aurora contributes up ∼80% (∼60%) total immediately after onset early expansion phase first (second) substorm, continues contribute ∼30–55% throughout remainder substorm. The estimated from ASI mosaic field view also peaked initial phase. Using measured tables produced Boltzmann Three Constituent (B3C) transport code (Strickland et al., 1976; 1993), conductance compared Poker Flat Incoherent Scatter Radar values, good agreement both discrete diffuse aurora.