This proposal is designed to study the electrodynamic coupling between the ionosphere and the magnetosphere at high latitudes. In particular, it will examine the coupling during periods when the interplanetary magnetic field (IMF) is northward. The dynamics of the ionospheric convection and the variation in the field-aligned electric currents (FACs) will be examined as the IMF By component varies. Images from the POLAR satellite will be combined with particle measurements from POLAR as well as particle and magnetic field measurements from the DMSP satellites. These data sets will be used to determine the field-aligned currents and the ionospheric conductivity. The information on the currents and ionospheric convection can then be used to determine the way energy is coupled into the ionosphere from the magnetosphere.
