ABSTRACT
Reverberation is the portion of the sound received at a hydrophone that is scattered by the ocean boundaries or by volumetric inhomogeneities. A research monograph by Jackson and Richardson is part of a new book series sponsored by the US Office of Naval Research on the latest research in underwater acoustics. The major source of volume reverberation in the sea has been established as biological. Different marine organisms affect different bands of the active sonar spectrum. Measurements of the depth variation of volume scattering strengths show an overall decrease with increasing depth. The roughness of the sea surface, the presence of trapped air bubbles make the sea surface an effective but complex scatterer of sound. Scattering can occur out-of-plane as well as within the vertical plane containing the source and the receiver. The Chapman-Harris empirical relationship adequately described surface backscattering for rougher seas at higher frequencies where scattering from bubble clouds is presumed to dominate the scattering process.
