The Effects of Small Geomagnetic Storms on Ionospheric Densities

Geomagnetic storms produce significant changes in Earths space environment. Small geomagnetic storms during solar minimum offer the opportunity to observe the effects of solar wind inputs on Earths atmosphere in isolation from other background changes in the ionosphere-thermosphere (IT) system. Here, we observe the effects of small storms on the ionosphere at middle and low latitudes, where disturbances in thermospheric winds and composition can produce storm-time changes in ionospheric densities. Using data from the NASA Ionospheric Connection Explorer (ICON), we investigate the competing effects of composition changes and neutral wind disturbances on modifying the ionosphere during storms, considering electrodynamic variations coming from both wind-dynamo and high latitude potentials. To identify the drivers of change in the ionosphere during small magnetic events, both the ionospheric F-region heights measured remotely and plasma velocities measured at the spacecraft are evaluated.