1pAO1. Ambient noise from the surf zone: Surface and acoustic waves.

Session: Monday Afternoon & Evening, May 13

Time: 1:05

Author: W. Kendall Melville
Location: Scripps Inst. Oceanogr., U.C.S.D., La Jolla, CA 92093-0213


Wave breaking is probably the dominant source of ambient noise in the ocean. In deep water, breaking is intermittent in both space and time, but, in the surf zone, every wave of any appreciable size breaks, or shoals, before it reaches the shore. This makes the surf zone and its neighboring region offshore acoustically different from deeper water. In shoaling, surface waves dissipate their energy, generate currents and turbulence that mix the water column, suspend sediments and entrain bubbles, and generate sound. It is the potential relationships between the sound generation and propagation and the other physical processes associated with surface waves, and the shoaling bottom topography, that is the subject of this talk. This is an open field in acoustical oceanography and underwater acoustics, with few measurements available but a great deal of potential. In this lecture the processes associated with the shoaling of surface waves will be reviewed and the resulting implications for sound generation and propagation will be discussed. The potential for the inversion of acoustic data to infer other surf zone processes will be explored.

from ASA 131st Meeting, Indianapolis, May 1996