Models of the geomagnetic field and characteristics of magnetic storms

The Earth&#8217;s magnetosphere is characterized by a considerable degree of dynamical complexity resulting from the interaction of different multiscale processes, which can be both directly driven/triggered by changes of the interplanetary medium condition, and due to internal processes of the magnetosphere. This complexity can be characterized by following both &#8220;classical&#8221; and &#8220;new&#8221; dynamical system tools. Recent work has demonstrated that recurrence plot based techniques may play a pivotal role in such an assessment.In this presentation, I will summarize some recent results on applications of recurrence quantification analysis and recurrence network analysis to different geomagnetic indices (Dst, SYM-H, ASY-H, AE) reflecting the variability of the Earth&#8217;s electromagnetic environment at different time-scales and magnetic latitudes. In addition, the same techniques are applied to some essential properties of the solar wind which are likely to have a relevant effect on geomagnetic field fluctuations and might serve as triggers of instability leading to geospace magnetic storms and/or magnetospheric substorms. The obtained findings underline that dynamical fluctuations of the geomagnetic field during periods of magnetospheric quiescence and storminess indeed exhibit distinctively different levels of dynamical complexity. Moreover, they provide additional evidence for a time-scale separation in magnetospheric dynamics that is further characterized by employing some multi-scale version of recurrence analysis utilizing a continuous wavelet transform of the signals of interest. The corresponding results can be of potential relevance for the development of improved approaches for space weather modelling and forecasting.&#160;References:R.V. Donner, V. Stolbova, G. Balasis, J.F. Donges, M. Georgiou, S. Potirakis, J. Kurths: Temporal organization of magnetospheric fluctuations unveiled by recurrence patterns in the Dst index. Chaos, 28, 085716 (2018)R.V. Donner, G. Balasis, V. Stolbova, M. Georgiou, M. Wiedermann, J. Kurths: Recurrence based quantification of dynamical complexity in the Earth's magnetosphere at geospace storm timescales. Journal of Geophysical Research - Space Physics, 124, 90-108 (2019)J. Lekscha, R.V. Donner: Areawise significance tests for windowed recurrence network analysis. Proceedings of the Royal Society A, 475 (2228), 20190161 (2019)T. Alberti, J. Lekscha, G. Consolini, P. De Michelis, R.V. Donner: Disentangling nonlinear geomagnetic variability during magnetic storms and quiescence by timescale dependent recurrence properties. Journal of Space Weather and Space Climate, 10, 25 (2020)

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Analysis of geomagnetic disturbances dynamics during increased solar activity and magnetic storms (according to the measurements of INTERMAGNET station network)

E3S Web of Conferences ◽

10.1051/e3sconf/201912702003 ◽

2019 ◽

Vol 127 ◽

pp. 02003

Author(s):

Oksana Mandrikova ◽

Anastasia Rodomanskay ◽

Alexander Zaitsev

Keyword(s):

Geomagnetic Activity ◽

Geomagnetic Field ◽

Auroral Zone ◽

Magnetic Storms ◽

Magnetic Data ◽

Field Variation ◽

Geomagnetic Disturbances ◽

Station Network ◽

Ground Station ◽

Automated Method

We present and describe an automated method for analysis of magnetic data and for detection of geomagnetic disturbances based on wavelet transformation. The parameters of the computational algorithms allow us to estimate the characteristics of non-uniformly scaled peculiar properties in the variations of geomagnetic field that arise during increasing geomagnetic activity. The analysis of geomagnetic data before and during magnetic storms was carried out on the basis of the method according to ground station network. Periods of increasing geomagnetic activity, which precede and accompany magnetic storms, are highlighted. The dynamic of geomagnetic field variation in the auroral zone is considered in detail.

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Characteristics of the variability of a geomagnetic field for studying the impact of the magnetic storms and substorms on electrical energy systems

Izvestiya Physics of the Solid Earth ◽

10.1134/s1069351318010032 ◽

2018 ◽

Vol 54 (1) ◽

pp. 52-65 ◽

Cited By ~ 9

Author(s):

V. B. Belakhovsky ◽

V. A. Pilipenko ◽

Ya. A. Sakharov ◽

V. N. Selivanov

Keyword(s):

Geomagnetic Field ◽

Energy Systems ◽

Electrical Energy ◽

Magnetic Storms ◽

Storms And Substorms ◽

The Impact

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Identification of the ground signatures of magnetospheric current systems as a function of latitude during intense magnetic storms

10.5194/egusphere-egu21-1436 ◽

2021 ◽

Author(s):

Vasilis Pitsis ◽

Georgios Balasis ◽

Ioannis Daglis ◽

Dimitris Vassiliadis

Keyword(s):

Solar Wind ◽

Magnetic Fields ◽

Geomagnetic Field ◽

Ring Current ◽

Magnetic Storms ◽

Quiet Time ◽

Maximum Correlation ◽

Current Form ◽

H Index ◽

Current Systems

We show that changes in the magnetospheric ring current and auroral currents during the magnetic storms of March 2015 and June 2015, are recorded in several specific ways by ground magnetometers. The ring current changes are detected in geomagnetic field measurements of ground stations at magnetic mid-latitudes from -50 to +50 degrees. The auroral currents changes are detected at high magnetic latitudes from 50 to about 73 degrees. Finally, for stations between 73 and about 85 degrees the measurements of the ground magnetometers seem to be directly correlated with the convection electric field VBSouth of the solar wind. Using the correlations among magnetic fields measured at stations ordered by latitude, a correlation diagram is obtained where the maximum correlation values for fields determined by the ring current form a distinct block. High-latitude magnetic fields from stations at higher latitudes, which are mainly determined by auroral currents, form a different block in the same diagram. This is in agreement with our earlier work using wavelet transforms on ground magnetic-field time series, where mid-latitude fields stations that are influenced mainly by the ring current, give a critical exponent greater than 2 while higher-latitude fields show a more complex dependence with two exponents. The maximum correlation values for mid-latitude fields correlated with the SYM-H index vary from 0.8 to 0.9, and, thus, we infer that those geomagnetic disturbances are mainly due to the ring current. The maximum correlations between the same fields and the solar wind VBSouth vary from 0.5 to 0.7. Fields at magnetic latitudes between 50 and 73 degrees exhibit greater correlation values for the AL index rather than the SYM-H index. This is expected since in the auroral zone, the convection- and substorm-associated auroral electrojets contribute significantly to the deviation of the geomagnetic field from its quiet-time value. In this case, maximum correlations vary between 0.6 and 0.7 for auroral latitude stations when compared with AL, as opposed to 0.4&#8211;0.5 when compared with SYM-H. Our results show how different measures of ground geomagnetic variations reflect the time evolution of several magnetospheric current systems and of the solar wind &#8211; magnetosphere coupling.

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