Equatorial Plasma Bubbles and Ionospheric Electrodynamics during Geomagnetic Storms

This is an in-person & virtual talk.

Equatorial plasma bubbles can occur at any geomagnetic activity level but occur more frequently during geomagnetic storms. In this study, we focus on prompt penetration events during major geomagnetic storms. We describe work to use numerical simulations with the coupled SAMI3/RCM first-principles model to understand ionospheric storm-time electrodynamics and plasma bubble formation. We use simulations results to estimate linear growth rates of the generalized Rayleigh-Taylor instability during major geomagnetic storms. The relative contributions of neutral and plasma dynamics are considered when examining the growth rates, with a specific focus on prompt penetration electric fields. For comparison, we utilize observation of plasma bubbles from the FPMU aboard ISS and TEC from GNSS. By comparing calculated growth rates to plasma bubble occurrence, we examine the role of storm-time electric fields in plasma bubble formation.