Abstract:

During the summer of 1995, a multidisciplinary, multilaboratory experiment entitled ``SWARM'' (shallow-water acoustics in a random medium) was conducted on the continental shelf off New Jersey. The purpose of this experiment was to examine the effects of internal waves, both linear and nonlinear, upon acoustic transmissions in the 10 to 1000-Hz range. Towards this goal, numerous oceanographic sensors were deployed along a fixed across shelf track, together with a fixed acoustic transmission range. Shipborne acoustic sources also allowed out of plane (along shelf) studies. Results will be presented of recent data analyses showing the nature of the measured acoustic travel time and intensity fluctuations, and how they correlate to environmental forcing, particularly by internal waves and the shelfbreak front. [Work supported by ONR.]