scholarly journals Relationship between geomagnetic storm development and the solar wind parameter ß

2021 ◽  
Vol 7 (4) ◽  
pp. 24-32
Author(s):  
Nadezhda Kurazhkovskaya ◽  
Oleg Zotov ◽  
Boris Klain
Keyword(s):  
Solar Wind ◽  
Geomagnetic Storms ◽  
Activity Cycle ◽  
Solar Activity Cycle ◽  
Solar Wind Plasma ◽  
Recovery Phase ◽  
Plasma Pressure ◽  
Superposition Method ◽  
Solar Wind Parameter ◽  
Dst Index

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.

scholarly journals Relationship between geomagnetic storm development and the solar wind parameter β

2021 ◽  
Vol 7 (4) ◽  
pp. 25-34
Author(s):  
Nadezhda Kurazhkovskaya ◽  
Oleg Zotov ◽  
Boris Klain
Keyword(s):  
Solar Wind ◽  
Geomagnetic Storms ◽  
Activity Cycle ◽  
Solar Activity Cycle ◽  
Solar Wind Plasma ◽  
Recovery Phase ◽  
Plasma Pressure ◽  
Superposition Method ◽  
Solar Wind Parameter ◽  
Dst Index

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.

scholarly journals INFLUENCE OF THE ß SOLAR WIND PARAMETER ON STATISTICAL CHARACTERISTICS OF THE Ap INDEX IN THE SOLAR ACTIVITY CYCLE

2019 ◽  
Vol 5 (4) ◽  
pp. 46-52
Author(s):  
Oleg Zotov ◽  
Boris Klain ◽  
Nadezhda Kurazhkovskaya
Keyword(s):  
Solar Wind ◽  
Solar Activity ◽  
Activity Cycle ◽  
Solar Activity Cycle ◽  
Statistical Characteristics ◽  
Solar Wind Parameter ◽  
Power Functions ◽  
Trigger Effect ◽  
Chaotic Modes ◽  
Ap Index

We have studied the effect of the β solar wind parameter (equal to the ratio of the plasma pressure to the magnetic pressure) on statistical characteristics of the Ap index reflecting the triggering behavior of the activity of Earth’s magnetosphere. The trigger effect of the dynamics of magnetospheric activity consists in the abrupt transition from the periodic mode to the chaotic mode in the solar activity cycle. It is shown that cumulative amplitude distribution functions and power spectra of the Ap index of both the periodic and chaotic modes are well approximated by power and exponential functions respectively. At the same time, the indices of power functions and the indices characterizing the slope of the Ap index spectrum differ significantly in magnitude for the periodic and chaotic modes. We have found that Ap nonlinearly depends on β for both the modes of magnetospheric dynamics. The maximum of the Ap index amplitude for periodic modes is observed when β>1; and for chaotic ones, when β<1. In almost every cycle of solar activity, the energy of the Ap index fluctuations of chaotic modes is higher than that of periodic ones. The results indicate intermittency and its associated turbulence of magnetospheric activity. The exponential character of the spectral density of the Ap index suggests that the behavior of magnetospheric activity is determined by its internal dynamics, which can be described by a finite number of deterministic equations. The trigger effect of magnetospheric activity is assumed to be due to the angle of inclination of the axis of the solar magnetic dipole to the ecliptic plane, on which the dynamics of the β parameter in the solar activity cycle depends.

scholarly journals Data derived NARMAX Dst model

2011 ◽  
Vol 29 (6) ◽  
pp. 965-971 ◽  
Author(s):  
R. J. Boynton ◽  
M. A. Balikhin ◽  
S. A. Billings ◽  
A. S. Sharma ◽  
O. A. Amariutei
Keyword(s):  
Mathematical Model ◽  
Solar Wind ◽  
System Identification ◽  
Nonlinear Systems ◽  
Wide Class ◽  
Geomagnetic Storms ◽  
Output Data ◽  
Dst Index ◽  
Geomagnetic Indices ◽  
Input And Output

Abstract. The NARMAX OLS-ERR methodology is applied to identify a mathematical model for the dynamics of the Dst index. The NARMAX OLS-ERR algorithm, which is widely used in the field of system identification, is able to identify a mathematical model for a wide class of nonlinear systems using input and output data. Solar wind-magnetosphere coupling functions, derived from analytical or data based methods, are employed as the inputs to such models and the outputs are geomagnetic indices. The newly deduced coupling function, p1/2V4/3BTsin6(θ/2), has been implemented as an input to model the Dst dynamics. It was shown that the identified model has a very good forecasting ability, especially with the geomagnetic storms.

scholarly journals The geomagnetic cutoff rigidities at high latitudes for different solar wind and geomagnetic conditions

2016 ◽  
Vol 34 (1) ◽  
pp. 45-53 ◽  
Author(s):  
W. Chu ◽  
G. Qin
Keyword(s):  
Solar Wind ◽  
Cosmic Rays ◽  
Strong Correlation ◽  
Geomagnetic Storms ◽  
Dynamic Pressure ◽  
Threshold Value ◽  
High Latitudes ◽  
Dst Index ◽  
Ae Index ◽  
Geomagnetic Cutoff

Abstract. Studying the access of the cosmic rays (CRs) into the magnetosphere is important to understand the coupling between the magnetosphere and the solar wind. In this paper we numerically studied CRs' magnetospheric access with vertical geomagnetic cutoff rigidities using the method proposed by Smart and Shea (1999). By the study of CRs' vertical geomagnetic cutoff rigidities at high latitudes we obtain the CRs' window (CRW) whose boundary is determined when the vertical geomagnetic cutoff rigidities drop to a value lower than a threshold value. Furthermore, we studied the area of CRWs and found out they are sensitive to different parameters, such as the z component of interplanetary magnetic field (IMF), the solar wind dynamic pressure, AE index, and Dst index. It was found that both the AE index and Dst index have a strong correlation with the area of CRWs during strong geomagnetic storms. However, during the medium storms, only AE index has a strong correlation with the area of CRWs, while Dst index has a much weaker correlation with the area of CRWs. This result on the CRW can be used for forecasting the variation of the cosmic rays during the geomagnetic storms.

Geoeffectiveness of the ‘Battle of Grunwald day’ in 2012

2020 ◽  
Author(s):  
Agnieszka Gil ◽  
Renata Modzelewska ◽  
Szczepan Moskwa ◽  
Agnieszka Siluszyk ◽  
Marek Siluszyk ◽  
...  
Keyword(s):  
Geomagnetic Storm ◽  
Transmission Lines ◽  
Geomagnetic Storms ◽  
Activity Cycle ◽  
Solar Activity Cycle ◽  
Solar Origin ◽  
Electric Transmission Lines ◽  
Cycle 24 ◽  
Ap Index ◽  
Halo Coronal Mass Ejection

&lt;p&gt;During the solar activity cycle 24, which started at the end of 2008, Sun was behaving silently and there were not many spectacular geoeffective events. Here we analyze the geomagnetic storm which happened on July 15 of 2012 in the 602 anniversary of the famous Polish Battle of Grunwald. According to the NOAA scale, it was G3 geomagnetic storm with Bz heliospheric magnetic field component dropping up to -20 nT, Dst index below -130 nT, AE index greater than 1300 nT and ap index being above 130 nT. It was proceeded by the solar flare of X1.4 class on 12 of July. This geomagnetic storm was accompanied by the fast halo coronal mass ejection 16:48:05 on 12 of July-the first C2 appearance, with the apparent speed 885 km/s and space speed 1405 km/s. This geomagnetic storm was classified as the fourth of the strongest geomagnetic storms from SC 24. Around that time in Polish electric transmission lines infrastructure, there was observed a significant growth of the number of failures that might be of solar origin.&lt;/p&gt;&lt;p&gt;&lt;em&gt;Acknowledgments: the Polish National Science Centre, grant number 2016/22/E/HS5/00406.&lt;/em&gt;&lt;/p&gt;

scholarly journals Super Strong Geomagnetic Storms and their Relation with Energetic Solar Features and Disturbances in Solar wind Plasma Parameters

2011 ◽  
Vol 2 (1) ◽  
pp. 152-156
Author(s):  
P.L.Verma P.L.Verma ◽  
◽  
Manoj Kumar Mishra ◽  
Monika Mishra ◽  
Preetum Singh ◽  
...  
Keyword(s):  
Solar Wind ◽  
Geomagnetic Storms ◽  
Solar Wind Plasma ◽  
Plasma Parameters

Solar Wind Variation with the Cycle

2000 ◽  
Vol 179 ◽  
pp. 423-429
Author(s):  
I. S. Veselovsky ◽  
A. V. Dmitriev ◽  
A. V. Suvorova ◽  
M. V. Tarsina
Keyword(s):  
Solar Wind ◽  
Coronal Holes ◽  
Activity Cycle ◽  
Solar Activity Cycle ◽  
Time Dependent ◽  
Solar Cycles ◽  
Solar Wind Density ◽  
Plasma Parameters ◽  
Decadal Variations ◽  
Wind Measurements

AbstractThe cyclic evolution of the heliospheric plasma parameters is related to the time-dependent boundary conditions in the solar corona. “Minimal” coronal configurations correspond to the regular appearance of the tenuous, but hot and fast plasma streams from the large polar coronal holes. The denser, but cooler and slower solar wind is adjacent to coronal streamers. Irregular dynamic manifestations are present in the corona and the solar wind everywhere and always. They follow the solar activity cycle rather well. Because of this, the direct and indirect solar wind measurements demonstrate clear variations in space and time according to the minimal, intermediate and maximal conditions of the cycles. The average solar wind density, velocity and temperature measured at the Earth’s orbit show specific decadal variations and trends, which are of the order of the first tens per cent during the last three solar cycles. Statistical, spectral and correlation characteristics of the solar wind are reviewed with the emphasis on the cycles.

Sign in / Sign up

Export Citation Format

Share Document