whitecap

hydrology

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Last updated

July 15, 2026

Quick Summary

A whitecap is a wave crest that breaks into white foam. This phenomenon occurs when waves grow in height, causing their crests to sharpen and become unstable. The wind's force and friction, along with pressure differences at the air-water interface, contribute to wave energy. As waves develop, their height and length increase. When a wave's height becomes too large relative to its length, the crest breaks, creating whitecaps. This breaking can happen in different ways, such as plunging or spilling types, as waves approach the shore.123

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wave
Physical characteristics of surface waves
…pointed crests break to form whitecaps. In shallow water the long-amplitude waves distort, because crests travel faster than troughs to form a profile with a steep rise and slow fall. As such waves travel into shallower water on a beach, they steepen until breaking occurs.
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…pointed crests break to form whitecaps. In shallow water the long-amplitude waves distort, because crests travel faster than troughs to form a profile with a steep rise and slow fall. As such waves travel into shallower water on a beach, they steepen until breaking occurs.
Read More

lake
Surface waves
This results in the familiar whitecaps. Waves that run ashore break up in surf. The wave height first decreases slightly, then increases, and the speed decreases, and eventually the wave form disappears as it crumbles into breakers. These can be plunging forms, in which the top curls right over the…
Read More
This results in the familiar whitecaps. Waves that run ashore break up in surf. The wave height first decreases slightly, then increases, and the speed decreases, and eventually the wave form disappears as it crumbles into breakers. These can be plunging forms, in which the top curls right over the…
Read More