Global responses of the coupled thermosphere and ionosphere system to the August 2017 Great American Solar Eclipse

The TEC enhancement was primarily the result of transport by the thermospheric wind perturbations associated with the eclipse-induced TADs. The perturbations of TEC, neutral temperature, and winds exhibited asymmetric distributions with respect to the totality path during the solar eclipse. Furthermore, ionospheric electrodynamic processes also play an important role in the global responses of the I-T system to the solar eclipse.

Unlike the case of large-scale TADs propagating from the eclipse region to other locations in the globe, the ionospheric electric fields and plasma drifts began to show significant perturbations even during the local pre-eclipse period when local wind and temperature had not been perturbed. This is related to the instantaneous global response of the ionospheric current system to changes in the ionospheric conductivity and winds in the eclipse region.