Research Highlights

The flow of ionospheric current can be probed by examining magnetic field measurements at the ground and at Low-Earth-Orbit (LEO) altitude. The interpretation of the magnetic field perturbations with respect of ionospheric current flow is complicated by the fact that the perturbations reflect the integrated effect of current flow close-by and far-away.

During geomagnetic disturbances, enhanced high‐latitude convection transports ionospheric F2‐region plasma from the dayside midlatitude region into the polar cap, leading to structures such as tongues of ionization (TOIs) and patches. In this study, we investigate the dynamic evolution of TOIs during the 17 March 2013 storm using a high‐resolution coupled thermosphere‐ionosphere‐electrodynamics model and Defense Meteorological Satellite Program (DMSP) satellite observations.

We conduct observational and modeling studies of thermospheric composition responses to weak geomagnetic activity (non-geomagnetic storms).

The National Aeronautics and Space Administration (NASA) Global‐scale Observations of the Limb and Disk (GOLD) has been imaging the thermosphere and ionosphere since October 2018. It provides continuous measurements over a large area from its geostationary orbit.

Magnetoseismology, a technique of magnetic field diagnostics based on observations of magnetohydrodynamic (MHD) waves, has been widely used to estimate the field strengths of oscillating structures in the solar corona.

In this multi-instrument paper, we search for evidence of sustained magnetic reconnection far beyond the impulsive phase of the X8.2-class solar flare on 2017 September 10.

The low latitude ionosphere is one of the dynamic regions of the Earth’s upper atmosphere. The morphology of this region is controlled by radiative and coupled chemical, neutral and plasma transport processes.

A recent statistical study (Qin et al., 2018) has suggested that not all electromagnetic ion cyclotron (EMIC) waves can scatter relativistic electrons. However, knowledge of the factors that influence the EMIC wave scattering efficiency is still limited in observations.

The Earth’s upper atmosphere impacts a wide range of technologies, including satellite communication and navigation signals. Specification and forecasting of the upper atmosphere are critical for mitigating these effects. Improved specification of the state of the upper atmosphere can also improve scientific understanding of this region.