A statistical study of BRIs (SMCs), isolated substorms, and individual sawtooth injections

There are many similarities and differences in the solar wind drivers during three of the main modes of convection in the magnetosphere (isolated substorms, global sawtooth oscillations, and steady magnetospheric convection (SMC) events, which we term here balanced reconnection intervals (BRI)). Thus, this investigation utilizes statistical analysis to compare the solar wind and interplanetary magnetic field (IMF) drivers and their steadiness (standard deviation divided by the mean) during these three different event types. By including the steadiness of the drivers, the importance of magnitude, sign, and stability of the drivers for the different modes can be investigated. A series of histograms with each mode plotted over top of 6 years of background is used to measure the deviation of the mode drivers from the nominal data, and also allows for a comparison between each event type. We found that the magnitude and direction of B z are the dominate driver for substorms, while BRIs and sawteeth require both magnitude and steadiness of certain drivers to occur. Both BRIs and sawteeth show similar steadiness in their drivers, while the magnitude of the drivers is much stronger for the sawtooth oscillations. Also included in this study are the substorms that initiate BRIs. The solar wind and IMF drivers for the initiating substorms are similar to drivers for BRIs; thus initiating substorms of BRIs are different from isolated substorms and may play a role in preconditioning the magnetosphere for BRIs.