The sea is blue for the same basic reasons that the sky is blue: the molecules that make up the sea (water, mostly), absorbs red light and scatters blue light. So the light that reaches your eye from the sea is usually blue.
Though if you were to go a few thousand meters down in the ocean, you would see nothing at all, because all of the sunlight is blocked by the water above.
The colour of the sea depends on how deep it is – shallow water looks more green than blue, but deep water looks blue because , as the others said, the other colours are absorbed more.
moe0001
The sea is blue for the same basic reasons that the sky is blue: the molecules that make up the sea (water, mostly), absorbs red light and scatters blue light. So the light that reaches your eye from the sea is usually blue.
Though if you were to go a few thousand meters down in the ocean, you would see nothing at all, because all of the sunlight is blocked by the water above.
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It’s to do with the blue light being scattered in relation to the other wavelengths and also the sea reflects the predominantly blue sky.
Check out this really quick clip: http://youtu.be/1PDm0xdio94
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The colour of the sea depends on how deep it is – shallow water looks more green than blue, but deep water looks blue because , as the others said, the other colours are absorbed more.
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