EFFECTS OF A SEDIMENT SCATTERING LAYER IN UNDERWATER-ACOUSTIC STUDIESOF INTENSITY SENSITIVITY AND DATA MATCHING

A scattering layer is introduced at a horizontal water-bottom interfac e to account for effects of attenuation due to bottom volume scatterin g. Using a wide-angle parabolic equation, a formula for the local mean intensity level is found for a shallow-ocean model consisting of thre e isospeed fluid layers: water, scattering layer, and bottom. The sens itivity of the theoretical mean to environmental parameters is studied , and the standard deviation of intensity is examined also. Comparison s are made between intensity statistics of the three-layer model and o f other isospeed models. Also, comparisons are made between three-laye r model statistics and data from a recent New Jersey Shelf experiment. Results from the inclusion of a scattering layer for the prediction o f relative intensity statistics are evaluated over a wide range of aco ustic frequencies. It is found that, with parameter values representat ive of the experimental site, the three-layer model can successfully m atch the local mean and standard deviation of the intensity data. (C) 1996 Acoustical Society of America.