Abstract:

A broadband sparse volume array has been developed to study ambient noise in the near shore region [J. Acoust. Soc. Am. 100, 2732(A) (1996)]. The array has been deployed along the coast of Boca Raton, FL, and it was found that, in the absence of boat traffic, biological noise sources were dominant and were concentrated in clusters around man-made structures or distributed over natural reefs. The sonar was deployed at different sites to triangulate on the location of these sources. Ambient noise maps of the coastal region were generated by combining the contribution from each source with a propagation model. These maps show the expected average sound pressure level from these biological sources as a function of depth and range in the along-shore and off-shore direction. Single hydrophone measurements have been made at different locations in the region to verify the maps. [Work supported by ONR.]