Atmospheric and ionospheric responses to Hunga‐Tonga volcano eruption simulated by WACCM‐X

High-resolution Whole Atmosphere Community Climate Model with thermosphere/ionosphere extension is used to simulate the responses to the Hunga-Tonga volcano eruption on 15 January 2022. Global propagation of the Lamb wave L'(0) and L'(1) pseudomodes are reproduced in the simulation, with the exponential growth of wave amplitudes with altitudes. The wavefront is vertical up to the lower thermosphere, and tilts outward above. These features are consistent with theoretical results. With simulated surface pressure perturbation agreeing with observations (similar to 100-250 Pa), thermospheric wind perturbations over 100 ms(-1) are comparable with reported satellite and ground-based observations. Traveling ionospheric disturbances in the total electron contents from the simulation show good agreement with observations, including magnitude and propagating speed and evidence of conjugacy in the first 1-2 hr after eruption. Conjugacy in E x B drift, on the other hand, is more persistent.