Calculating Atmospheric Gravity Wave Parameters from Infrasound Measurements

Abstract

Infrasound arrays are sensitive enough to be able to detect the subtle pressure changes that occur as an overhead atmospheric gravity wave passes. The array can then provide information regarding the back azimuth, amplitude, frequency and pressure perturbation of the gravity wave. It is shown that by combining this data with meteorological data recorded at the array, further gravity wave parameters can be calculated. Some examples of time series analysis are shown for an infrasound station in the Ivory Coast illustrating how seasonal and daily variations in the weather can change the properties of gravity waves being detected. Ultimately, the parameters calculated using this method can be used by the meteorological community to improve the parametrisation of gravity waves in their models and increase understanding of the diurnal and seasonal variability in gravity wave parameters.