[P-EM12] Coupling Processes in the Atmosphere-Ionosphere System

[PEM12-07] Atmospheric and Ionospheric Responses to Hunga-Tonga Volcano Eruption Simulated by WACCM-X

★Invited Papers

*Hanli Liu¹, Wenbin Wang¹, Joseph D Huba², Peter H Lauritzen³, Francis Vitt^1,4 (1.National Center for Atmospheric Research, High Altitude Observatory, 2.Syntek Technologies, 3.National Center for Atmospheric Research, Climate and Global Dynamics, 4.National Center for Atmospheric Research, Atmospheric Chemistry Observations and Modeling)

Keywords:whole atmosphere modeling, Lamb wave, volcano eruption

Numerous observations have shown large global responses to the Hunga Tonga-Hunga Ha'apai Volcano Eruption on January 15 2022 in the lower, middle and upper atmosphere. It is of interest to simulate this event using a whole atmosphere model, in order to better understand the physical processes involved, interpret the observations, and also to test the model capability. In this study, the NCAR Whole Atmosphere Community Climate Model with thermosphere/ionosphere extension (WACCM-X) is used to simulate this event. High spatial resolution configuration is used, with horizontal resolution of ~25km and vertical resolution of 0.1 scale height in most of the middle and upper atmosphere. The model is initialized with a surface pressure perturbation around the epicenter. The magitude of the initial perturbation is choosen to produce propagating surface pressure perturbations consistent with observations. The model simulates Lamb waves with increasing wind and temperature amplitudes with altitude, reaching over 100m/s and 100K, respectively, in the thermosphere. Large perturbations in ionospheric ExB drifts and strong traveling ionospheric disturbations (TIDs) are also simulated, with magitudes comparable with observations. Detailed analysis of the wave structures will be presented in this talk.