Outer Boundary Conditions for the Inner Magnetosphere: Global Simulation Perspective

Activity in the inner magnetosphere is a complex function of the driving solar wind, processes in the magnetotail, and coupling to the ionosphere. Global MHD simulations are great tools to study the solar wind - magnetosphere interaction on one hand and magnetosphere - ionosphere coupling on the other. Therefore, even if the MHD description does not give a full account of the complexity of the inner magnetosphere multi-component, multi- temperature plasmas, it does give self-consistent and dynamic boundary conditions of the driving solar wind and magnetotail as a source region. In this presentation we discuss magnetopause reconnection and energy entry in a series of global MHD simulations using the GUMICS-4 code. The simulation parameters have been selected to represent a variety of conditions: low and high Mach numbers, low and high solar wind speed, and small and large, northward and southward IMF conditions. We discuss the relationship between energy entry through the magnetopause and energy entry into the inner magnetosphere and the dependence of these processes on the driving solar wind and IMF conditions.