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I understand that the conservation of energy essentially says that "energy can neither be destroyed or created but that it is transferred from one form to another." Given that, on the ocean, wind energy gets transferred to the sea where it then takes the form of a wave. Ocean waves travel sometimes a thousand kilometers or more. When a wave reaches the shore or a reef it breaks. My question is where does that ocean wave energy go after it breaks, I know it creates sound which is sound energy but that does not seem like enough. Where does the energy go when the sound dies out? Where does the energy go?

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    $\begingroup$ The answer to basically any "where does the energy go?" question is : "heat". You just need to wait long enough. And in that case, you don't need to wait for long. $\endgroup$ – Eric Duminil Dec 3 '17 at 8:15
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    $\begingroup$ Consider that when you drive your 2 ton car 80mph (speak for myself) and slow down to a stop, almost all of that energy has been converted to heat in your break pads! Heat can store a lot more energy than you might think. $\endgroup$ – user12029 Dec 3 '17 at 9:03
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    $\begingroup$ Especially when water is involved. It takes a massive amount of heat to warm up large amounts of water. $\endgroup$ – SomeoneSomewhereSupportsMonica Dec 3 '17 at 9:51
  • $\begingroup$ One thing that is consistent with all of this that I have learned is that energy seems to either love to be stored in the form of a solid or exist in the form of a wave, or in the form of wind energy, but that's close to a wave as well. $\endgroup$ – Brando Dec 4 '17 at 4:36
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This is an interesting article with some numbers for the energy in waves

waves

A wave with a height of 2 m and a wavelength of 14 m breaking along 2 km of coastline (surface area = 32,000 m2) has approximately 45 kWh of energy.

How it will be dissipated will depend on the approach to the coast.

A wave as seen above will start losing energy by transferring it to kinetic and rotational energy at the shallow bottom including sand transfers, which finally will become heat (extra kinetic energy). As there will be conservation of momentum also, part of it will be absorbed by the impact on the earth, as vibrations which will also end up as heat, and also any dissipation in air as you observe. In the picture above sand will be continually deposited on the shore changing the shore line.

A wave hitting a rocky precipice will be transferring vibrations (finally heat) but also will erode part of the rock.

In the end all energy will end up as a higher temperature in the region and ground than if the ocean were calm.

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  • $\begingroup$ Thank you for your answer. the amount of heat that is created by the breaking wave is so imperceptibly small that I never could have imagined that that was what was happening, but it does make perfect sense. the energy goes from wind to water to sound and heat. Now I need to find out where the energy comes from before it is wind energy. Rotation of the earth perhaps? $\endgroup$ – Brando Dec 3 '17 at 18:50
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    $\begingroup$ The sun heats the atmosphere land and ocean unevenly ( night day, summer ,winter)which generates atmospheric circulation (storms and winds). The energy comes from the sun ( well maybe some active volcanos and internal earth heat will change temperatures also and affect the winds and storms). The rotation affects the wind circulation and the weather systems but sun is the main energy source $\endgroup$ – anna v Dec 3 '17 at 19:00
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    $\begingroup$ @Brando Yes. If you want to trace it all the way back in that way, you are solar surfing! Or, if you feel like taking it a bit further, you're surfing on echos of the big bang. Totally tubular, man! $\endgroup$ – Cort Ammon Dec 4 '17 at 0:59
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    $\begingroup$ @Brando: Almost all energy on earth comes from the sun. There are some exceptions: nuclear energy (yes, there are such things as natural nuclear reactors) and geothermal. Everything else is from the sun. For example, petrol comes from ancient organic matter which at some point come from ancient plants which gets energy from the sun. Now think about firewood: photons from the sun inject enough energy for plants to make sugar which gets converted to cellulose which becomes wood. Every time you burn wood you're releasing light from the sun. $\endgroup$ – slebetman Dec 4 '17 at 3:48
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    $\begingroup$ the earth is also continuously radiating black body radiation en.wikipedia.org/wiki/Black-body_radiation keeping the temperature balanced in thermodynamic equilibrium, what comes in from the sun goes eventually out since does not t burn up but has on average a specific temperature. $\endgroup$ – anna v Dec 4 '17 at 4:51
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When a wave breaks on the shore, most of the kinetic energy that was propagated in the wave goes into vigorously stirring up the water and mixing it with air as it runs up and then down the beach slope. In so doing it also shoves sand and pebbles around as pointed out by JMLCarter. The stirring action dissipates energy via the viscosity of the water, which warms up by a tiny amount, and that heat is then shared with the sand and air nearby.

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Costal errosion. Movement of sand and stones etc.

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