SubAuroral red arcs generated by inner magnetospheric heat flux and by subauroral polarization streams

They are usually attributed to subauroral electron heating by inner magnetospheric heat flux (IMHF). However, the role of IMHF in changing the ionosphere-thermosphere (IT) still remains elusive.

We conduct controlled numerical experiments with the Thermosphere-Ionosphere Electrodynamic General Circulation Model (TIEGCM). Coulomb collisional heat flux derived with the Comprehensive Inner Magnetosphere Ionosphere (CIMI) model and empirical subauroral polarization streams (SAPS) are implemented in TIEGCM. The heat flux causes electron temperature enhancement, electron density depletion, and consequently SAR arcs formed in the dusk-to-midnight subauroral ionosphere region.