Vertical Coupling Between Tropospheric Blocking, Stratospheric Dynamics, and Ionospheric Response During Sudden Stratospheric Warmings

Sudden stratospheric warmings (SSWs) initiate a sequence of vertically propagating dynamical processes that extend from the troposphere to the ionosphere. This study examines the coupling chain linking Ural blocking (ZUL), stratospheric polar vortex variability (U), and the ionospheric polar cap height (PCH) using a lag-composite analysis centered on major SSW events. The composite reveals a robust temporal ordering: ZUL peaks approximately one week before SSWonset, U reverses at day 0, and PCH exhibits a delayed increase several days afterward. These results demonstrate a coherent ZUL → U → PCH coupling pathway and highlight the role of tropospheric blocking in initiating multi-layer atmospheric and ionospheric variability.