Classifications of substorm and storm triggering mechanisms

The extent to which solar wind conditions drive substorms remains unclear. Statistical studies have shown that approximately 60% of substorms appear to be driven by external solar wind conditions, while the remaining 40% cannot be associated with a solar wind trigger. Statistical analysis and data mining techniques are being used to analyze over ten years of satellite and earth-based data with the intent of developing a system for classification of storms and substorms based on solar wind conditions and storm characteristics. Results from such data analyses form a preliminary classification system from which a representative sample of events is selected. Each of the sample events is then analyzed using 3D multi-fluid simulations for the purpose of gaining insight into the processes dominating substorm onset, and for further refining the preliminary classification scheme.