The Latitudinal Dependency of the Solar Eclipse-Induced Ionosphere Response on 14 October 2023

We analyzed the three-dimensional (3-D) ionosphere response to the 14 October 2023 solar eclipse via assimilating multisource total electron content (TEC), including dense global navigation satellite system and the Constellation Observing System for Meteorology, Ionosphere, and Climate. The assimilations reveal a latitudinal dependency of the eclipse-induced TEC depletion, with larger reductions occurring at middle latitudes. In contrast to the electron density depletion throughout all ionosphere heights at middle latitudes, the equatorial ionization anomaly (EIA) region exhibits an altitudinal variation and an asymmetry pattern in density response. The implemented National Center for Atmospheric Research Thermosphere Ionosphere Electrodynamics General Circulation Model simulations align well with the 3-D electron density assimilations. Diagnostic analysis indicates that the photo-chemical process plays a primary role in the larger depletion at middle latitudes, and the neutral wind transport provides a minor secondary contribution. In contrast, wind transport emerges as a dominant factor near the EIA region. The transequatorial plasma transport associated with northward neutral wind, driven by eclipse-induced local cooling, combined with partly enhanced upward ExB drift, mitigates the total TEC depletion near the EIA region. This study highlights the importance of the dynamic coupling for a self-consistent I-T system between the neutral atmosphere and the ionosphere during eclipses.