In studies of the Earth's ionosphere, a hot topic is how to estimate ionospheric conductivity. This is hard to do for a variety of reasons that mostly amount to a lack of measurements. In this study we use satellite measurements to estimate electromagnetic work and ionospheric conductances in both hemispheres. We identify where our model estimates are inconsistent with laws of physics, which partially solves a previous problem with unrealistic predictions of ionospheric conductances.

In this study, we use a multipoint analysis of conjugate magnetospheric and ionospheric observations to investigate the magnetospheric and ionospheric responses to fast flow bursts that are associated with different space weather conditions. The results show that ionospheric currents are connected to the magnetospheric flows for different space weather conditions. The connection is more apparent and global for flows that are associated with a geomagnetically active condition.

We report that the ionospheric plasma flow patterns associated with the J-shaped transpolar arc (a type of nightside distorted TPA), detected by the SuperDARN radar, reveal the formation process of the nightside distortion of a TPA. Equatorward flows at the TPA growth point were observed flowing out of the polar cap and then turning toward the pre-midnight main auroral oval along the TPA nightside distortion. These ionospheric flow patterns would cause the distortion at the TPA nightside end.

In this paper we have used Cluster EDI data in combination with the CODIF cusp dataset from Slapak et al. (2017) to obtain parallel and convection velocities for oxygen ions; 69 % of total oxygen outflow from the high-altitude cusps escapes the magnetosphere on average; 50 % escapes tailward beyond the distant X-line. The oxygen capture-versus-escape ratio is highly dependent on geomagnetic conditions. During active conditions, the majority of oxygen outflow is convected to the plasma sheet.

When the terrestrial magnetic field is disturbed, particles from the near-Earth space can precipitate into the upper atmosphere. This work presents, for the first time, numerical simulations of proton precipitation in the energy range associated with the production of aurora (∼1–30 keV) using a global kinetic model of the near-Earth space: Vlasiator. We find that nightside proton precipitation can be regulated by the transition region between stretched and dipolar geomagnetic field lines.