Spatial and temporal ion drift variability in the high -latitude F region during southward IMF

The purpose of the following research is to investigate the role and contribution of variability or structure in the ion drift to the overall Joule heating rate during times of southward interplanetary magnetic field (IMF). This investigation is limited to southward IMF because the convection patterns are generally more stable and reproducible than those seen for a northward IMF. This allows us to organize the data according to features of the convection pattern and thus produce results that can be used in model simulations of the ionosphere-thermosphere. The contribution of variability or structure in the ion drift to the overall Joule heating is organized into two parts. The first part focuses on the characteristic spatial structure in the ion drift in the F-region ionosphere and how it relates to the bulk ion flow, the large-scale spatial gradient in the bulk ion flow, and the ion temperature. We consider separately the polar cap and auroral zone during the summer and the winter at dawn and dusk during times of steady southward IMF. The second part of this investigation examines the spatial and temporal variability in the ion drift and its contribution to the total Joule heating rate in the F-region ionosphere in the summer and the winter at all magnetic local times (MLT) that are sampled by our data set. This second investigation includes more data than the first investigation by relaxing the stability conditions for southward IMF as well as allowing weaker southward IMF. These topics are investigated utilizing data from the Dynamics Explorer 2 (DE-2) satellite.