Multi‐Step Gravity Wave Propagation From a Tropospheric Vortex to the Ionosphere Near the Tibetan Plateau

Abstract The atmosphere and ionosphere form a vertically coupled system in which disturbances in the lower atmosphere can modulate ionospheric variability. Using reanalysis data, ground‐based GNSS observations, and COSMIC‐2 profiles, we investigate gravity waves (GWs) generation and upward coupling during a southwest vortex (SWV) event over the Tibetan Plateau in June 2022. The results reveal a multi‐step process: primary gravity waves are excited near the tropopause by vortex‐induced dynamical disturbances and propagate upward. These primary waves dissipate at ∼45–50 km, depositing momentum and energy that may generate secondary gravity waves. The secondary waves may propagate further upward and contribute to the generation of higher‐order gravity waves, which penetrate into the ionosphere and generate persistent medium‐scale traveling ionospheric disturbances (MSTIDs). These findings demonstrate that ionospheric responses to tropospheric vortex systems cannot be explained solely by direct upward propagation, highlighting the critical role of multi‐step vertical coupling in atmosphere‐ionosphere.