Mesopause Airglow Disturbances Driven by Nonlinear Infrasonic Acoustic Waves Generated by Large Earthquakes

Near-epicentral mesopause airglow perturbations, driven by infrasonic acoustic waves (AWs) during a nighttime analog of the 2011 M9.1 Tohoku-Oki earthquake, are simulated through the direct numerical computation of the 3D nonlinear Navier-Stokes equations. Surface dynamics from a forward seismic wave propagation simulation, initialized with a kinematic slip model and performed with the SPECFEM3D_GLOBE model, are used to excite AWs into the atmosphere from ground level. Simulated mesopause airglow perturbations include steep oscillations and persistent nonlinear depletions up to 50 % and 70 % from the background state, respectively, for the hydroxyl OH(3,1) and oxygen O(1S) 557.7-nm emissions. Results suggest that AWs excited near a large earthquake's epicenter may be strong enough to drive fluctuations in mesopause airglow, some which may persist after the AWs have passed, that could be readily detectable with ground- and/or satellite-based imagers. Synthetic data demonstrate that future airglow observations may be used for the characterization of earthquake mechanisms and surface seismic waves propagation, potentially complementing tsunami early-warning systems based on total electron content (TEC) observations.