The plasmaspheric plume is an important region of detached plasma elements and provides an effective coupling channel of energy/mass between the inner magnetospheric plasmasphere and outer magnetosphere. In this study, using Van Allen Probe data, we present a statistical result of plasmaspheric plumes in the inner magnetosphere, which implies that the plumes tend to occur during the recovery phase of geomagnetic storms, and the occurrence rate is larger during stronger geomagnetic activity.

A rare gravity wave event was observed on the night of 25 April 2017 over northern Germany. An all-sky airglow imager recorded an upward-propagating wave at different altitudes in mesosphere with a prominent wave front above 91 km and faintly observed below. Based on wind and satellite-borne temperature profiles close to the event location, we have found the presence of a leaky thermal duct layer in 85–91 km. The appearance of this duct layer caused the wave amplitudes to diminish below 91 km.

This study showed the ionospheric response over low-latitude regions in Brazil predicted by Martínez-Ledesma et al. (2020) for the solar eclipse event on 14 December 2020. We used a multi-instrumental and modeling analysis to observe the modifications in the E and F regions and the Es layers over Campo Grande and Cachoeira Paulista. The results showed that solar eclipses can cause significant ionosphere modifications even though they only partially reach the Brazilian low-latitude regions.

The Lehtinen–Pirjola (LP) method is widely used for modelling geomagnetically induced currents (GIC) in power systems but was developed when the main aim was to model GIC in only the highest voltage level of a power network. Here we present a modification to the LP method designed to provide an efficient method for modelling GIC in multiple voltage levels. We also show how existing software can easily be converted to the new method and provide examples of calculations.

This paper presents observations of FTE-type flux ropes on the dayside during BepiColombo's Earth flyby. FTE-type flux ropes are a well-known feature of magnetic reconnection on the magnetopause, and they can be used to constrain the location of reconnection X-lines. Our study suggests that the magnetopause X-line passed BepiColombo from the north as it traversed the magnetopause. Moreover, our results also strongly support coalescence creating larger flux ropes by combining smaller ones.

The HIBAR rocket launched on 28 January 2003 into the nightside aurora in order to measure high-frequency radio waves with both parallel and perpendicular antennae. The rocket encountered several short high-frequency radio wave bursts with a secondary wave associated with them, believed to be a product of a nonlinear wave–wave interaction of the initial wave with observed lower-frequency waves. Nonlinear waves are not often observed, and their dynamics are of significant interest.

We analysed all-sky camera images observed at Mt. Bohyun observatory (36.2° N, 128.9° E) for the period of 2017–2019. We retrieved gravity wave parameters including horizontal wavelength, phase velocity and period from the image data. The horizontally propagating directions of the wave were biased according to their seasons, exerted with filtering effect by prevailing background winds. We also evaluated the nature of vertical propagation of the wave for each season.