RELATIONSHIP BETWEEN GEOMAGNETIC STORM DEVELOPMENT AND THE SOLAR WIND PARAMETER ß
Journal Title: Solar-Terrestrial Physics - Year 2021, Vol 7, Issue 4
Abstract
We have analyzed the dynamics of solar wind and interplanetary magnetic field (IMF) parameters during the development of 933 isolated geomagnetic storms, observed over the period from 1964 to 2010. The analysis was carried out using the epoch superposition method at intervals of 48 hrs before and 168 hrs after the moment of Dst minimum. The geomagnetic storms were selected by the type of storm commencement (sudden or gradual) and by intensity (weak, moderate, and strong). The dynamics of the solar wind and IMF parameters was compared with that of the Dst index, which is an indicator of the development of geomagnetic storms. The largest number of storms in the solar activity cycle is shown to occur in the years of minimum average values (close in magnitude to 1) of the solar wind parameter β (β is the ratio of plasma pressure to magnetic pressure). We have revealed that the dynamics of the Dst index is similar to that of the β parameter. The duration of the storm recovery phase follows the characteristic recovery time of the β parameter. We have found out that during the storm main phase the β parameter is close to 1, which reflects the maximum turbulence of solar wind plasma fluctuations. In the recovery phase, β returns to background values β~2‒3.5. We assume that the solar wind plasma turbulence, characterized by the β parameter, can play a significant role in the development of geomagnetic storms.
Authors and Affiliations
Kurazhkovskaya N. A. , Zotov O. D. , Klain B. I.
INFLUENCE OF GEOMAGNETIC DISTURBANCES ON SCINTILLATIONS OF GLONASS AND GPS SIGNALS AS OBSERVED ON THE KOLA PENINSULA
We have compared effects of geomagnetic disturbances during magnetic storms of various types (CME and CIR) and during an isolated substorm on scintillations of GLONASS and GPS signals, using a Septentrio PolaRx5 receiver...
IONOSPHERIC EFFECTS OF TWO SOLAR FLARES IN THE MAXIMUM OF SOLAR CYCLE 23 AND IN THE MINIMUM OF SOLAR CYCLE 24
Using data from the GPS and GLONASS navigation satellite systems, we analyze the responses of the mid-latitude ionosphere to the extreme solar flares that occurred at the maximum of solar cycle 23 (October 28, 2003) and...
OBSERVING MAGNETOSPHERIC WAVES PROPAGATING IN THE DIRECTION OF ELECTRON DRIFT WITH EKATERINBURG DECAMETER COHERENT RADAR
This paper deals with Pc5 magnetospheric pulsations featuring positive azimuthal wave numbers registered with the mid-latitude coherent decameter radar located near Ekaterinburg (EKB). The azimuthal wave numbers are dete...
FEATURES OF ARTIFICIAL IONOSPHERE TURBULENCE INDUCED BY THE O- AND X-MODE HF HEATING NEAR THE F2-LAYER CRITICAL FREQUENCY
We present experimental results from the studies of large-scale inhomogeneities along the external magnetic field with increased electron density, electron temperature, and excitation of elongated plasma waves (Langmuir...
COMPARISON BETWEEN PROBABILITY DENSITY FUNCTIONS OF VERTICAL ELECTRIC CURRENT IN SOLAR ACTIVE REGIONS BASED ON HMI/SDO AND SOT/HINODE DATA
Studying electric currents in solar active regions (AR) is an essential step in understanding solar activity in general and solar flares in particular. In this paper, we compare probability density functions of vertical...