Steady magnetospheric convection events: How much does steadiness matter?

Using a new method to identify steady magnetospheric convection events (SMCs), a list of more than 2000 SMCs is compiled over the 11 years between 1997 and 2007. The SMCs are then categorized by the fluctuations in their AL. Active SMCs have large fluctuations in AL and therefore a less steady magnetosphere in terms of small‐scale activity. Classic SMCs fall in the middle 50% for AL steadiness and represent the average of the SMCs. Calm SMCs have very little changes in AL and are the steadiest of the three categories. When investigating the solar wind drivers, it is found that the steadiness of the drivers is less important than the strength of the driving. Active SMCs have stronger drivers with the exception of Alfvenic Mach number and solar wind beta. The SYM‐H of the three categories is also investigated for the approximate storm time conditions of the events. Calm SMCs rarely occur during storm time when SYM‐H is less than −50 nT. If an SMC is identified during storm time, then it tends to be a more active event. Key Points A study of three types of SMCs based on the steadiness of AL The effect of solar wind driving on active, classic, and calm SMCs The SYM‐H during active, classic, and calm SMCs