Multi‐Instruments Observation of Ionospheric‐Thermospheric Dynamic Coupling Over Mohe (53.5°N, 122.3°E) During the April 2023 Geomagnetic Storm

Abstract

AbstractThe state and variations of the Ionosphere‐Thermosphere (I‐T) system are strongly influenced by dynamical processes, with these effects being amplified during intense space environment disturbances such as geomagnetic storms, producing multi‐scale disturbance features in the I‐T system. The redistribution of energy and momentum through the dynamical processes is currently not well understood. Unfortunately, the dearth of thermospheric observations has yielded limited studies capable of monitoring and analyzing the I‐T dynamical coupling during storms using co‐located measurements. This work examines the responses of the I‐T system during the April 2023 geomagnetic storm based on high‐resolution continuous I‐T system observations at Mohe observatory, a middle latitude station. Both large‐scale features and short‐period oscillations were identified in multiple key parameters of the I‐T system. Similar disturbed patterns in thermospheric winds occurred during the main and recovery phases of the geomagnetic storm. However, the oscillation features in many parameters of the I‐T system are only observed during the main phase. The results of concurrent I‐T system observations unveil the oscillation features of thermospheric winds, temperatures, the ionospheric F2 peak height, electron density, and total electron content. These findings reveal the important influence of wind divergence on thermospheric temperature disturbances and its modulatory effect on ionospheric disturbances.