The Role of High Latitude Drivers in Accurately Modeling the Thermospheric and Ionospheric Response to Geomagnetic Storms

Abstract:

The drivers of the upper atmosphere include the solar irradiance, tides and gravity waves from the lower atmosphere, particle precipitation and electric fields in the high altitude region, and electron heat flux from the magnetosphere and solar wind. These drivers can vary dramatically depending on conditions. Typically, the irradiance is the strongest driver in the thermosphere and ionosphere, but during times of strong driving, the high latitude forcing can become dominant. In global models of the ionosphere and thermosphere, the electric field and particle precipitation are specified separately, and are typically derived from different data sources. If these are not consistent with each other, the location and strength of energy added to the system can be incorrect. Also, varying models of the electrodynamics predict very different patterns of precipitation and electric fields, giving contrasting heating patterns. Further, many models of the aurora do not include features such as polar cap arcs and small-scale intense features within the aurora. In this presentation, a variety of storms will be presented, showing the effects of varying the high-latitude drivers on the thermospheric density, composition and temperatures as well as the ionosphere state.