The non‐linear response of the magnetosphere: 30 October 1978

Abstract

Previous efforts to find evidence of deterministic nonlinear dynamics in the global geomagnetic system have treated the geomagnetic system as autonomous. However, the geomagnetic system is strongly driven by the stochastic solar wind. We consider the response of the magnetosphere, as given by the AE index, for one day when the IMF had a nearly constant southward value. Using both a series of non-linear statistics and non-linear prediction of the response to the input signal $v B_s$, we find that there is some evidence for deterministic non-linear response of the Earth's magnetosphere on that day.Comment: 4 pages, Postscript file compressed and uuencoded, made with uufiles scrip

Forecasting auroral electrojet activity from solar wind input with neural networks

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Dynamical characteristics of magnetospheric energetic ion time series: evidence for low dimensional chaos

“…These results were further supported by a series of studies including chaotic analysis of ground measured magnetospheric signals with AE index data (Vassiliadis et al, 1990(Vassiliadis et al, , 1992Roberts et al, 1991;Shan et al, 1991;Pavlos et al, 1992aPavlos et al, , b, 1994Klimas et al, 1996). A series of significant studies (Price and Prichard, 1993;Price et al, 1994;Prichard, 1995) showed the weakness of the nonlinear analysis of the magnetospheric AE index time series, especially in relation to the strong null hypothesis of Theiler (Theiler et al, 1992a, Correspondence to: M. A. Athanasiu (mathanas@ee.duth.gr) b). In a recent series of papers by Pavlos et al (1999a, b, c), Athanasiu and Pavlos (2001), the hypothesis of magnetospheric chaos, supported by the analysis of the magnetospheric AE index, was reestablished.…”

Geometrical characteristics of magnetospheric energetic ion time series: evidence for low dimensional chaos

“…Parallel to these studies a fruitful criticism has been developed about the supposition of magnetospheric chaos, especially in relation to its experimental evidence (Prichard andPrice, 1992, 1993;Price and Prichard, 1993;Price et al, 1994;Prichard, 1995), based on the strong null hypotheses for stochasticity of Theiler (Theiler et al, 1992a, b). The above criticism includes the following assertions:…”