Breaking wave on a beach.
Surface waves can be caused by several different sources, such as passing boats, wind, and rain. Most of the sound of breaking waves is radiated from bubbles trapped under water at the wave’s leading edge. The movement and breaking of these bubbles cause strong underwater sounds. Bubbles left by the wake of a passing ship can be identified for almost an hour after the event. Ambient noise in the frequency range of 200-50,000 Hz is mostly due to spray and bubbles associated with breaking waves. It increases with increasing wind speed.