1pAO8. Acoustic measurements of breaking waves in the surf zone.

Session: Monday Afternoon & Evening, May 13

Time: 3:30

Author: Grant B. Deane
Location: Scripps Inst. of Oceanogr., Mail Code 0238, La Jolla, CA 92093-0238


A series of measurements have been made to characterize the sound generated by breaking waves in the surf zone around Scripps Pier. Simultaneous video and acoustic data were made to allow the acoustic energy radiated by individual waves to be correlated with the breaking event at the surface. The acoustic measurements were made directly below breaking waves in 2 m of water and 170 m from the shoreline. Spectral analysis of the data demonstrates the presence of a strong acoustic field below the breaking waves. Overhead waves generate sound for some several seconds, and are clearly distinguishable from nearby surf. The breaking wave spectrum is bimodal, with two peaks in intensity around 30 and 1000 Hz. A preliminary analysis of the data shows an acoustically active region of water propagating with the breaking wave. [Work supported by ONR.]

from ASA 131st Meeting, Indianapolis, May 1996