Predictions of acoustic backscattering from oceanic stratification interfaces

The ocean is primarily composed of a series of increasingly dense fluid layers, defined by density stratification interfaces where medium properties, such as temperature and salinity, drive changes in medium density and compressibility. The transport of dissolved constituents (e.g., oxygen, heat, salt) between these oceanic fluid layers is strongly influenced by the intensity of the stratification interface. Active acoustics allow for high resolution observations of these interfaces, offering continuous data collection over broad spatial scales. In this work, we present a one-dimensional acoustic scattering model for predicting acoustic backscatter from stratification interfaces. The model is widely applicable to acoustic water column data collected with ship-mounted sonars and preliminary results, based on hydrographic profiles, suggest that, in many oceanic cases, sound speed perturbations drive the majority of acoustic scattering. Additionally, modeling results predict a frequency modulated backscattering intensity based on the sharpness of the stratification interface, suggesting the potential for remote estimation of medium properties through broadband acoustic inversion.