Statistics of Magnetic Impulsive Events

A large number of transient phenomena are observed in the dayside magnetosheath, magnetosphere, and ionosphere, all of which are specific signatures of the mechanisms that drive the solar wind-magnetosphere interaction and/or the magnetosphere-ionosphere coupling. This makes all of them important objects of investigation and understanding. This study concerns high latitude magnetic impulsive events (MIE) as observed in the network of magnetometer stations in Greenland. A database of MIE events have been created based on data for the years 1995 through 2001. Identification is done with a computerized algorithm as well as by visual inspection and the results from both approaches will be presented and discussed. A comprehensive set of distribution functions for the events will be presented, including their dependency on season, geomagnetic activity, and solar wind parameters. The results will be discussed in terms of their ability to distinguish between proposed generation mechanisms for the events.