Measured and modeled O+ upwelling at 800 km: Understanding the dayside asymmetry

Contemporary magnetosphere modelers are now including species dependent dynamics. Energetic O+ has significant consequences for the ring current stored energy and perhaps the timing of substorm injections. The mechanism by which thermal O+ escapes from the top of the ionosphere and into the magnetosphere is not fully understood. The history of field lines and the importance of this history as a function of MLT in driving O+ outflows has not been fully investigated as contributor to the physical explanation of various outflow features. In this study we used the Field Line Inter-hemispheric Plasma (FLIP) model to model thermal flows in the auroral zone. We will present 1) a comparison of modeled flows to flows observed by DMSP at 800 km and 2) contributions of low altitude processes to creating the asymmetries in dayside vertical O+ flows observed by several instruments over the last 3 decades.