Interplanetary Shock Propagation Model: A Model for Predicting Solar-Flare-CausedGeomagnetic Storms, Based on the 2 1/2 D, MHD Numerical Simulation Results from the Interplanetary Global Model (2D IGM)

摘要

A numerical model has been devised to predict the time of arrival at Earth ofinterplanetary shocks caused by solar disturbances at arbitrary longitudes on the Sun. This report first describes the physical basis of the model, which is a parametric study of solar-caused, energetic, interplanetary shocks. The input shocks in the parametric study are characterized by three parameters; the initial shock velocity, the source duration, and the source angular extent, or width. The net energy added to the solar wind by the source is expressed in terms of these parameters. Because of the lack of an observable proxy for the source width, an average value is used for that parameter in this model. This average value is computed from a data set on the assumption that both the model and the associations made in the data set are valid. These shock observations were associated with both source flares and subsequent sudden commencements, or geomagnetic storms at Earth, which serve as markers of shock arrival at Earth.