Related papers: Characteristics and development of the main phase …
Studies of vertical and interhemispheric coupling during Sudden Stratospheric Warmings (SSWs) suggest that gravity wave (GW) momentum flux divergence plays a key role in forcing the middle atmosphere, although observational validation of GW…
Plasma pressure distribution in the inner magnetosphere is one of the key parameters for understanding the main magnetospheric processes including geomagnetic storms and substorms. However, the pressure profiles obtained from in-situ…
In this paper, we present for the first time a comprehensive statistical study between type II radio bursts from the metric (m) to the dekameric-hectometric (DH) domain and their associated solar and space weather (SW) phenomena, namely,…
We investigate the solar origin and heliospheric evolution of an intense geomagnetic storm that occurred on March 23-24, 2023. Despite multiple candidate CMEs observed between March 19-21, a weak CME detected on March 19 at 18:00 UT was…
The scale separation approximation, which is in the base of the solar mean field dynamo models, can be hardly justified both by observations and theoretical applications to astrophysical dynamos.{ The general expression for the mean…
In this study, we investigate thermospheric neutral mass density heating associated with 168 CME-driven geomagnetic storms in the period of May 2001 to September 2011. We use neutral density measured by two low-Earth orbit satellites: CHAMP…
Interplanetary Coronal Mass Ejections (ICMEs) are prominent drivers of space weather disturbances and mainly lead to intense or extreme geomagnetic storms. The reported studies suggested that the planar ICME sheath and planar magnetic…
During strong magnetic storms, the errors of determination of the range, frequency Doppler shift and angles of arrival of transionospheric radio signals exceeds the one for magnetically quiet days by one order of magnitude as a minimum.…
Records of Dst, Kp and Sym-H indexes are analyzed looking for evidences of possible precursors for magnetic storms. To accomplish this task the main magnetic storms were located and some periods immediately before storms and some periods…
We have performed an analysis of case events and statistics of positive ionospheric storms in the dayside region of the equatorial ionization anomaly during recurrent geomagnetic storms (RGSs), which dominate in geomagnetic and ionospheric…
The relationship between moderate and extremely high levels of geomagnetic activity, represented by the Kp index (2- to 5+ and 6- to 9), and solar wind conditions during southward IMF intervals was revealed utilizing a newly developed…
In this study, we investigate the global ionospheric impact of high-speed solar wind streams/corotating interaction regions (HSS/CIR). A series of ten such events are identified between December 1st 2007 and April 29th 2008, characterized…
The evolution of magnetospheric indices on temporal scales shorter than that of substorms is characterized by bursty, intermittent events that may arise from turbulence intrinsic to the magnetosphere or may reflect solar wind-magnetosphere…
On the basis of morphological analysis of yearly values of the maximum CME (coronal mass ejection) speed index, the sunspot number and total sunspot area, sunspot magnetic field, and solar flare index, the solar wind speed and…
Interplanetary coronal mass ejections (ICMEs), the large-scale eruptive phenomena capable of shedding a huge amount of solar magnetic helicity and energy are potential in driving strong geomagnetic storms. They complexly evolve while…
The solar magnetic activity cycle is responsible for periodic episodes of severe space weather, which can perturb satellite orbits, interfere with communications systems, and bring down power grids. Much progress has recently been made in…
This paper presents a study of the global medium-scale (scales<620 km) gravity wave (GW) activity (in terms of zonal wind variance) and its seasonal, local time and longitudinal variations by employing the enhanced-resolution (~50 km) Whole…
Atmospheric neutral density is a crucial component to accurately predict and track the motion of satellites. During periods of elevated solar and geomagnetic activity atmospheric neutral density becomes highly variable and dynamic. This…
This study aims at the early diagnostics of geoeffectiveness of coronal mass ejections (CMEs) from quantitative parameters of the accompanying EUV dimming and arcade events. We study events of the 23th solar cycle, in which major…
We investigate spatio-temporal evolution of high-degree acoustic mode frequencies of the Sun and the surface magnetic activity, over the course of multiple solar cycles, to improve our understanding of the connection between the solar…