We analyzed an event of short term ozone variability due to the passage of the polar vortex over Río Gallegos (southern Argentina) with the aim of highlighting the capability of the Millimeter-Wave Radiometer to observe ozone in the stratosphere and the low mesosphere with a high temporal resolution. It is particularly important in this subpolar region due to the high variation that this gas can suffer as a consequence of the passage of the polar vortex and the ozone hole during spring.

We study the impact of geomagnetic storm of September 6–9, 2017 on the low-to-mid latitude ionosphere. The study is based on analyzing the data from GPS stations and the magnetometer observatories located Asia, Africa and America. The GPS data is used to derive the global, regional and vertical total electron content (TEC) in the selected regions. The storm time response of the TEC over the Asia is earlier than Africa and America. The positive storm effects in the vTEC occur in low latitudes.

To simulate the vertical propagation of atmospheric waves, experimental data on pressure variations at the Earth’s surface are used. These data are associated with the meteorological source. The simulation results have allowed to the first time estimate the amplitudes of temperature wave disturbances in the upper atmosphere caused by waves from the atmospheric front. The simulations have been performed using the Lomonosov supercomputer.

Earth's bow shock in solar wind with high thermal and low magnetic pressure is a rare phenomenon. However such an object is ubiquitous in astrophysical plasmas. These conditions are usually quite transient. We survey statistics of such shock observations since 1995. About a hundred crossings were initially identified. In this report 22 crossings by Cluster project are studied with multipoint analysis, allowing to determine spatial scales.

Simulations of locally breaking gravity wave hotspots in the stratosphere show a suppression of wave propagation at midlatitudes leading to a displacement of the polar vortex towards lower latitudes. This effect is highly depending on the position of the artificial gravity wave forcing. It is strongest (weakest) for hotspots at lower to middle latitudes (higher latitudes).

The statistical results of PMSE layered occurrence ratio (OR) observed by EISCAT 224 MHz radar over the period 2004–2015 are given in this paper. The seasonal variation of PMSE mono-, double- and tri-layer occurrence ratio was analyzed. A method was given to calculate the PMSE layered OR under different electron density threshold conditions. The method solves the defect that the measurements of EISCAT radar is discontinuous, which makes a significant breakthrough in the description of the PMSE.

The solar flare effects on ionospheric absorption at mid- and low-latitude have been investigated with the systematic analysis of ionosopheric parameters (fmin, dfmin: deviation from the reference days). A solar zenith angle-dependent enhancement of the parameters was detected but the observed values also depended on the flare insensity. The dfmin parameter found as a good qualitative proxy for the relative variation of ionospheric absorption especially during the less intense solar flares.

The latest research suggests that there could be a relationship between geomagnetic field variations and seismic events in different parts of the planet. These variations have been found in both ground-level magnetometers and satellites studying the ionosphere. The magnetic variations are similar between the earthquakes in Chile (2010, 2014, 2015) and the one in Mexico 2017. Therefore, the use of magnetic variations at ground level or ionospheric could show seismic precursors.

Although solar eclipses often occur above Indonesia, observations on ionospheric dynamics during solar eclipse have not been widely carried out. The results contained in this research, such as information related to the decrease of total electron conrent (both temporally and spatially) and scintillation behavior when facing a unique phenomenon such as solar eclipse can be used as a reference for the next solar eclipse not only for Indonesia but also for another region.

Using the Beijing MST radar echo power observations collected during the period November 2011–May 2017, the structure and variability of the tropopause over Xianghe, China (39.75° N, 116.96° E) was presented. Our comparison results showed a good agreement between the radar and thermal tropopauses during all seasons. Whereas the consistency between the radar and dynamical tropopauses is poor during summer. Diurnal oscillation in tropopause height is commonly observed during all seasons.

Blanco-Cano et al. (2018) intended to find a type of transient event in the solar wind before the terrestrial bow shock using a special type of simulation. However, the simulation results cannot reproduce the main features of the event. Not only are the physical indicators missing from the simulation result, but the footprints and the signs of the event formation processes too. Based on the remarks described below, I am sure that the features in the simulations are not those type of events.

The fundamental mode of oscillations of the solar atmosphere, f-mode, plays an important role in solar physics. At an early stage of observing, it was found that its frequency is related to the wavelength by a ratio characteristic of waves on the surface of deep water. Subsequent observations revealed its inaccuracy. We derived waves with a different frequency-wavelength ratio and compared them with other possible waves of this type both in the solar and in the terrestrial atmosphere.

The Earth's radiation belts control the space environment often affecting the GPS signal propagation and satellite operations. Intense fluxes of energetic particles can penetrate even below the inner belt near the equator. We analyzed electron penetrations under geomagnetic quiet conditions and found in the solar wind an external driver caused that. Satellite observations prove that disturbance of the inner belt was associated with impact of plasma jets formed in the solar wind nearby the Earth.

Our research explores a new method for identifying where and when the magnetic field lines in Earth's magnetotail may change its topology through the reconnection process, during which a sudden release of magnetic energy can lead to the brightening of aurora, a process called substorm. Traditionally, the magnetic reconnection was often interpreted using a two-dimensional model, which however does not capture the intrinsically three-dimensional nature of reconnection physics, as we have revealed.

Higher TEC day-to-day variations during the daytime than nighttime for all the years were observed. The diurnal variation shows OBS-TEC rising rapidly from a minimum just before sunrise between 03:00–05:00 LT (~ 2 TECU) in 2011, 04:00–05:00 LT (~ 3 TECU) in 2012, 03:00–05:00 LT in 2013 (~ 3 TECU), and 03:00–05:00 LT in 2014 (~3 TECU). OBS-TEC is found to increase to a broad daytime maximum between 00:12 LT 354–00:16 LT for all years before falling to a minimum after sunset.