The Relative Timing of Substorm Onset Phenomena
Abstract
Current debate over the initiation of a magnetospheric substorm centers on two viable onset models. One model is that substorm onset begins with disruption of the near-Earth crosstail current. The other possibility is that onset begins with magnetic reconnection in the midtail plasmasheet, and that subsequent dynamics are driven by convective flow bursts. Each model predicts a different temporal ordering of onset phenomena. We present the results of event studies where we examine the temporal ordering of convective plasma flow in the plasmasheet, Pi2 pulsations, and auroral arc brightening. Using the causal link between midtail plasma flows and low latitude Pi2 pulsations and the relative timing of phenomena we show that the observed sequence of events disagrees with predictions of CD models. We then show that the observations lend strong support to the flow-burst model of magnetotail dynamics.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2003
- Bibcode:
- 2003AGUFMSM22D..05K
- Keywords:
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- 2740 Magnetospheric configuration and dynamics;
- 2744 Magnetotail;
- 2764 Plasma sheet;
- 2788 Storms and substorms