Ionospheric perturbations in the American southern middle latitude during the Sudden Stratosphere Warming events

Ionospheric perturbations during the Sudden Stratosphere Warming (SSW) events reflect the lower atmosphere-ionosphere coupling and thus become a research hot-spot. Nevertheless, most previous related studies focused on the low latitude. Comparatively, ionospheric perturbations in the middle and high latitudes during the Arctic SSW events are relatively less studied. The current work analyzed the ionosphere perturbations in the American southern middle latitude during the Arctic SSW with total electron content and NmF2. Unexpected strong connection between the major Arctic SSW and the ionospheric variations in the American southern middle latitude were detected. Upper thermosphere circulation anomaly and the enhanced semi-diurnal lunitidal influence during the SSW may be crucial to such connection.