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Earth's Magnetosphere . Multiscale Magnetosphere. Strongly driven magnetosphere: 81 intense storms ( 2001). . Conditional Probability Distribution Functions: . . . Multiscale phenomenon . Veeramani et al., 2007,Sharma et al., Ann. Geo., 2008. Modeling Dynamics in Multiscale Systems. Global behavior Data-derived modeling of dynamics - low dimensional (mean-field) - predictable dynamics (weighted mean field)Multiscale phenomenon Statistical properties.
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1. Complexity of the Magnetosphere: Dynamical and Statistical Features Surja Sharma
University of Maryland, College Park
2. Earths Magnetosphere
3. Multiscale Magnetosphere
5. Conditional Probability Distribution Functions:
6. Modeling Dynamics in Multiscale Systems
13. Spatio-Temporal Dynamics: Mutual Information Function
14. Average Mutual Information
15. Average Mutual Information (6-hr averages)
16. Long-range Correlations Measure of inherent behavior
Characterizes underlying statistical processes
Clustering of events
Extreme events Nonequilibrium systems
17. Detrended Fluctuation Analysis (DFA) Detection of long-range correlations in time series data
Based on auto-correlation function C(s)
Removes effects due to non-stationarities
Yields a scaling exponent:
F(s) ~ s-a
a = 0.5 - uncorrelated (diffusion)
> 0.5 - long-range correlation
18. Auto-correlation Function of AL index
19. Mutual Information Function AL index
20. DFA analysis of AL index
21. DFA Analysis of Solar Wind Bz
22. DFA Analysis Return Intervals
23. Recurrence Time Distribution
24. Recurrence Time Distribution
25. Magnetosphere : 3D Picture
27. Summary Three approaches:
Nonlinear dynamics (Data-derived modelng)
Statistical Physics (Non-equilibrium?)
Simulations
(MHD on global scale and EMHD on shortest scales)
Improved data-derived modeling: Forecasting global behavior
Mean-field and weighted mean-field approach
Spatio-temporal modeling: Mutual information functions
Multiscale nature of the magnetosphere
Unpredictable component
Conditional (Bayesian) probabilities
Long-term Correlations
DFA - Uncorrelated behavior beyond 5 hrs