Effects of Variable Average Auroral Energy Flux on Thermospheric Circulation: GITM Simulations

The average auroral energy is a crucial parameter involved in the specification of auroral energy input into global models of the upper atmosphere and ionosphere. The distribution and magnitude of auroral energy is responsible for modifications in auroral structure as well as thermospheric composition. Clarifying the effects of changes in auroral energy on the global thermospheric circulation is critical to resolving open questions related to uncertain modeling of thermospheric heating and cooling rates during elevated geomagnetic activity, as well as modeling and prediction of the associated changes in auroral conductance which directly impact the ability to forecast ground-based magnetic perturbations. We conduct GITM simulations where the average energy is modified by a scale factor ranging from 0.5 to 2, and we demonstrate the resultant effects on thermospheric circulation through model-data comparisons with Nitric Oxide cooling from TIMED/SABER as well as the neutral density from the GOCE spacecraft.