This collaborative project will address feedback mechanisms between the ionosphere and geomagnetic storm dynamics and will investigate a possible role of the ionosphere on the variability of magnetic storm intensity. A particular scientific objective is the investigation of universal time (UT) dependence of geomagnetic storm intensity. A combination of data analysis and numerical experiments will be used to evaluate the effects of the ionosphere on the UT-dependence in geomagnetic storm intensity. This project incorporates numerical experiments using modeling components from the University of Michigan Space Weather Modeling Framework (SWMF) to gain insight into the role of the ionosphere on geomagnetic storm intensity. The study will also use GPS-determined global Total Electron Content (TEC) maps to characterize the middle and high latitude ionosphere during all levels of magnetic activity. Magnetic activity indices and TEC data will be used to empirically evaluate a possible feedback mechanism of the ionosphere on the storm intensity. The data will further be used to constrain the model experiments. Using the coupled space-weather model, SWMF, the project will investigate the degree to which high-latitude oxygen ion abundance changes vs. season and magnetic activity, using the TEC data to evaluate the validity of the ionospheric component of the SWMF simulations.
