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Nonlinear variability of SYM-H over two solar cycles


Fractal fluctuation analysis is applied to ground-based SYM-H data during quiet times and during magnetic storm times spanning two solar cycles between 1981–2002. On the basis of Kp, intervals were selected that corresponded to quiet and active magnetospheric dynamics. A nonlinear detrended fluctuation analysis (DFA) was applied to monitor nonlinear variability over the solar cycles. We find significant variations in nonlinear statistics between quiet and active intervals, which indicates a difference in statistical variability for quiet times, and storm times.


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Correspondence to J. A. Wanliss.

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Wanliss, J.A. Nonlinear variability of SYM-H over two solar cycles. Earth Planet Sp 56, e13–e16 (2004).

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Key words

  • SYM-H
  • fractals
  • nonlinear
  • space weather
  • indices
  • geomagnetism
  • Dst
  • prediction