TransWikia.com

Ocean waves breaking slowly at the shore during periods of turbulence

Physics Asked by Sketcher on January 3, 2021

During storms, I have often watched ocean waves breaking at the shore as if they were in slow motion. I’ve wondered if the slow curling of the waves during these times was somehow due to their increased power, when compared to waves breaking faster under calmer conditions. However, it has occurred to me that remarkably slow breaking of the ocean waves during storms when viewed from the shore may also be due to opposing force vectors of air and/or water currents, such as air rushing through the trough under a wave curl, or air and/or water currents opposing the wave action in another manner somehow. I have noticed these slow wave movements even when the wind is coming in strong from the ocean, which one might presume would make waves break quicker. Is there a simple correlation between the power of a wave and its breaking or curling speed?

One Answer

There are long papers published just on this topic! The rate, and height, of a wave's transition from smooth sinusoidal form to breaker depends on its speed, wavelength, and crucially on the rate of change of water depth as the wave approaches land (or reef, or whatever). Waves only break because the deeper portions of the wave are slowed down due to frictional interaction with the ocean floor.

This is separate from the mechanisms which cause "whitecaps" on open water, where the wind reaches some critical speed and is able to more or less tear the peak section of the waves loose from the body of the wave.

Fluid dynamics is to blame for both these behaviors; I fear I am nowhere near expert enough to identify the exact formulas to apply.

Answered by Carl Witthoft on January 3, 2021

Add your own answers!

Ask a Question

Get help from others!

© 2024 TransWikia.com. All rights reserved. Sites we Love: PCI Database, UKBizDB, Menu Kuliner, Sharing RPP