Impact of explosion-generated acoustic waves on atmospheric layers

Abstract

Explosive events, such as artificial or accidental explosions, and volcanic eruptions, among others, generate low-frequency acoustic waves that propagate through and perturb atmospheric and ionospheric layers (e.g., the hydroxyl and oxygen airglow layers, the sodium layer, and the ionospheric D-region). The subsequent disturbances (i.e., airglow emission intensity, sodium or other minor species density, or electron density fluctuations) are potentially detectable by optical or radio remote sensing methods. Understanding and quantifying the impact of acoustic waves on atmospheric layers are, therefore, crucial steps for establishing detectability thresholds (e.g., relative to source scales and effective yields). In this work, we investigate the propagation of upwardly-traveling acoustic perturbations induced by 1t to-1 kt of TNT-equivalent ground explosions and their signatures on different atmospheric layers. Specifically, we estimate the amplitudes and periods of the induced fluctuations of hydroxyl, sodium, and electron densities at mesospheric through lower-thermospheric altitudes. This work investigates the potential of such layers to serve as sensors for characterizing lower-atmospheric explosive events and the complementarity of such indirect measurements with direct sensing, e.g., of pressure fluctuations in situ.