Global comparison between ocean ambient noise modelling and infrasound network observations

Abstract

<p>The International Monitoring System (IMS) of the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) may be used to detect atmospheric explosions and events of interest using infrasound technology. However, ambient noise may affect the detection performance of the station network, and particularly ocean noise known as microbarom, as previously shown by characterizing ambient noise through broadband array processing on IMS data. Indeed, ocean wave interactions generate acoustic noise almost continuously. In this study, we use wave action models and include bathymetry and source directivity effects to model the microbarom sources and perform a global comparison between the synthetic signals obtained from two-dimensional spectrum ocean wave products, and observations. With this study, it is expected to enhance the characterization of the ocean-atmosphere coupling and to discriminate the impact of different features to account for in models. In return, better knowledge of microbarom sources allows to better characterize explosive atmospheric events and to provide information about the middle atmosphere dynamics and disturbances that could be used as model constraints</p>