The long wavelengths of the light spectrum—red, yellow, and orange—can penetrate to approximately 15, 30, and
50 meters(49, 98, and 164 feet), respectively, while the short wavelengths of the light spectrum—violet, blue and green—can penetrate further, to the lower limits of the euphotic zone. Blue penetrates the deepest, which is why deep, clear ocean water and some tropical water appear to be blue most of the time. Moreover, clearer waters have fewer particles to affect the transmission of light, and scattering by the water itself controls color.
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