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THE DIRECTIONAL DISTRIBUTION OF AMBIENT NOISE IN THE OCEAN
SCRIPPS INSTITUTION OF OCEANOGRAPHY SAN DIEGO CALIF MARINE PHYSICAL LAB
Anisotrophy of deep ocean ambient noise in the frequency range of 750 to 1500 C was investigated, vertical and azimuthal dependencies were isolated, the identity of sources contributing to nonuniform distributions was established, and the radiation patterns of such sources were inferred. Deep ocean ambient noise was anisotropic at sea states above zero. The surface of the ocean was a major contributor to nonuniform distributions and the radiation patterns of such surface sources were deduced. Vertical anisotrophy was attributed to the superposition of a noise field due to the radiating ocean surface upon an isotropic field present in the absence of surface radiation. The intensity, at a receiver due to a unit incremental surface radiator of intensity, at one yard, can be considered as the intensity due to direct transmission or specular bottom reflection with attenuation due to spherical spreading and absorption occurring over the separation between radiator and receiver. Author