Ionospheric Total Electron Content Response to the Great American Solar Eclipse of 21 August 2017

Abstract

AbstractUsing a comprehensive database of ~4,000 ground‐based Global Navigation Satellite Systems stations, we investigate the ionosphere's response to the 21 August 2017 solar eclipse. The high‐resolution, two‐dimensional maps of the ionospheric total electron content (TEC) were constructed using combined GPS and GLONASS measurements. Solar eclipse resulted in a continent‐size TEC decrease with stronger effects up to 50% over the U.S. eastern coast. Along the totality path within an area of 75% obscuration TEC decreased by ~30–40%. We reveal a latitudinal dependence of the TEC response with equatorward expansion of TEC depletion. Recovery signature in the form of large‐scale TEC enhancement up to 20–30% occurred in posteclipse period. Swarm and DMSP satellites encountered the eclipse‐induced plasma density depletion and posteclipse increase at 450 km height and above. These effects were associated with downward plasma fluxes from topside ionosphere/plasmasphere and thermospheric changes.