Influence of surf noise on oceanic ambient noise in coastal waters with sandy seabed

Abstract

Wave breaking almost always occurs at the surf zone in the ocean. The underwater noise generated by breaking waves in the surf zone is called the surf noise. The characteristics of surf noise are not well known because of measurement difficulties. The underwater noise was measured to investigate the influence of surf noise on oceanic ambient noise in the eastern sandy coast of the middle part of the Korean Peninsula. As a result, the wave breaking in the surf zone generated an oceanic ambient noise within the frequency bands between 50 Hz and 1 kHz, but this noise did not propagate well because the wavelength was long compared to the depth. The surf noise generated in the surf zone of the sandy bottom affected the oceanic ambient noise, especially in the frequency bands between 50 and 300 Hz, within a range of about 1.25 km from the shoreline. (C) 2014 The Japan Society of Applied Physics