Why Are Oceans Blue?
Sunlight is made up of all the colors of the rainbow: Red, orange, yellow, green, blue, and violet. Some of the sunlight is reflected off the surface of the water, reflecting the color of the sky. Some of the sunlight penetrates the water and is scattered by ripples and particles in the water (this tinges the appearance of the ocean with the color of the particles). In deep water, much of the sunlight is scattered by the oxygen in the water, and this scatters more of the blue light.