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| Titel |
Investigating dynamical complexity in the magnetosphere using various entropy measures |
| VerfasserIn |
G. Balasis, I. A. Daglis, C. Papadimitriou, M. Kalimeri, A. Anastasiadis, K. Eftaxias |
| Konferenz |
EGU General Assembly 2009
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 11 (2009) |
| Datensatznummer |
250021418
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| Zusammenfassung |
| The complex system of the Earth’s magnetosphere corresponds to an open spatially extended
non-equilibrium (input - output) dynamical system. The non-extensive Tsallis entropy has
been recently introduced [Balasis et al. (2008), Geophys. Res. Lett., 35, L14102,
doi:10.1029/2008GL034743] as an appropriate information measure to investigate dynamical
complexity in the magnetosphere. The method has been employed for analyzing Dst time
series and gave promising results, detecting the complexity dissimilarity among different
physiological and pathological magnetospheric states (i.e., pre-storm activity and
intense magnetic storms, respectively). This paper explores the applicability and
effectiveness of a variety of computable entropy measures (e.g. Block entropy, Kolmogorov
entropy, T -complexity and Approximate entropy) to the investigation of dynamical
complexity in the magnetosphere. We show that as the magnetic storm approaches there
is clear evidence of significant lower complexity in the magnetosphere. Overall,
Approximate entropy and Tsallis entropy yield superior results for detecting dynamical
complexity in the magnetosphere in comparison to the other entropy measures presented
herein. Ultimately, the analysis tools developed in the course of this study for the
treatment of Dst index can provide convenience for space weather applications. |
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