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When we are in beach we can see waves coming when the sun light goes of the waves amplitude will increase what is the reason Some people said me that for moon light the frequency and velocity of waves will increase What is the reason behind that? but only at night these waves frequency will increase what makes it so

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How sure are you that you are asking about a real effect? I've lived on coastlines several times and can't say I ever noticed a reliable difference in wave action between night and day: tide and whether have large and reasonable obvious effects. – dmckee Aug 29 '11 at 20:23

It doesn't, all acepted models of wave generation base solely on force transmission by wind, current, sea states and gravity. Any "light inducted effect" if ever exist is neglected by comparasion with the other forces.


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Light and heat from the sun causes the water to worm up and evaporate causing air currents which in turn changes the frequency of the waves. The divergence of heat absorption of the land and the ocean courses a temperature difference which in turn causes large masses of air to flow and change the wave size and frequency. At night when the temperature somewhat equalizes the wind dies down the waves mellow out and the frequency changes. Now by earth standards these are local effects. You need to study the major air currents and the colories effect of the earth spinning has on global wave currents and air flow

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I too have heard this phenomenon. At night, the waves will suddenly go lap-lap-lap-lap-lap-lap very quickly.

At night, things are very calm, and the only waves are very tiny. At my local beach, the day time waves might be two or three feet tall. Nice body surfing. At night and early the next morning, the water is calm and the waves are small maybe 6 inches. Being small, they have a short distance between them so they come quickly. Since it is calm, they are very regular and precise. There are various interference phenomena.

If you have two sources of such waves, their action will depend upon the sum of the two waves. Since the source frequencies cannot be identical, there is a "beat" that develops. You can lay in bed hearing nothing at all. No breaking waves anywhere. And then a constructive interference begins to form and when they agree you will hear lap-lap-lap quickly.

The angle of the wave front to the beach is normally zero, but when the direction is off then little curls will form as the wave breaks at different stations along the beachfront. You can then hear a lap-lap-lap that travels from right to left in stereo.

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