Measurements of the Bottom Loss Magnitude and Phase from 5 to 50 kHz and 10 to 77 degrees grazing at the Experimental Validation of Acoustic modeling techniques (EVA) Sea Test

The value of the specular bottom loss is an important parameter for modeling the propagation of acoustic waves in littoral areas. In shallow waters, even short range propagation can have many interactions with the ocean bottom. Bottom loss is affected by many envorinmental parameters including the reflection coefficient, which is dependent on the sediment type, and scattering from the water/sediment interface. The phase and magnitude of the reflection coefficient from 5 to 50 kHz and 10 to 77 degrees grazing from a rough sand/water interface were taken as part of the Experimental Validation of Acoustic modeling techniques (EVA). The experiment was conducted off the coast of Isola dElba in October 2006. The measurements were corrected for beam pattern and rough interface scattering effects and compared with two current models describing acoustic interaction with ocean sediments, the elastic model and the Effective Density Fluid Model (EDFM) [1]. Both models are corrected for spherical wave effects using the experimental geometry.