Numerical Modeling of Coseismic Tropospheric Disturbances Arising from the Unstable Acoustic Gravity Wave Energetics

Abstract

Numerous recent studies report the Coseismic Tropospheric Disturbances (CTDs) during large earthquakes. Their presence suggests the importance of atmospheric seismology in a possible earthquake forecasting scenario. The origin mechanism and associated energetics of CTDs are not well understood though the observations associate them with the atmospheric waves. We present the numerical modeling of coupled dynamics of Gravity waves (GWs) and convective instability (CI) in the dry troposphere that produces the CTDs, in the form of pressure disturbances, of observed magnitudes. The study reveals the altitude and epicentral distribution of CTDs and elaborates the relative role of GWs and CI in the generation and intensification of CTDs. The study finds that mega and strong earthquakes disturb the troposphere to a similar level as the severe meteorological weather.

Keywords

• tropospheric disturbances
• convective instability
• gravity wave