Energy moving, water staying
Do Waves Carry Water Along?
A wave moves energy across the sea. The water mostly just circles in place.
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Step 1 of 5
Wind drags on the surface.
Air rubbing across water piles up small ripples. Once there are ripples, the wind has something to push against, and they grow.
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Step 2 of 5
Size depends on wind, time and distance.
A strong wind blowing a long time over a long stretch of open water builds big waves. Any of the three being small keeps waves small.
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Step 3 of 5
A floating object bobs, it does not travel.
Watch a gull on the swell: it rises, moves slightly forward, sinks, moves back. It circles roughly in place while waves pass beneath.
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Step 4 of 5
So the wave is a moving shape.
What crosses the ocean is the pattern of rising and falling, not the water. The same is true of a ripple through a stadium crowd.
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Step 5 of 5
Waves break because the bottom slows them.
In shallow water the base drags on the seabed while the crest keeps its speed. The top overtakes the bottom and topples forward.
Surfers ride the forward-moving water of a breaking wave — the one moment when water really does travel with it.
The short version
Ocean waves move energy while the water circles in place, and they break when the seabed slows their base.
Try it yourself
Float a cork in a bowl and make waves at one end. The cork bobs and stays put — the wave crosses without it.
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