The reflection of the sky and the sun in the water.
Louis has sea green eyes, which sometimes appears to have a hint of blue.
Because seawater is almost completely transparent, but does have a color. When you put a small quantity in your hand (or in a cup), it will seem transparent, but in large bodies of water it definitely has a color. That's why a sea as a whole appears green, but a handful of sea water doesn't.
Sea water appears blue due to the way it absorbs and scatters sunlight. Water molecules absorb colors in the red part of the light spectrum, while blue light is scattered and reflected back to our eyes, making the sea water appear blue.
The wather itself does not change colour, it just appears to. The sky is reflected by the surface of the sea, you'll often notice that the sea seems dull looking on an overcast day. Also, what's in the water will affect the colour of the sea. Once a year, Phytoplankton (tiny plants) bloom in huge numbers. This will make the sea appear green.
The Black Sea appears dark in color due to its depth and the presence of organic material and minerals in the water. It can also appear blue-green depending on the lighting and surrounding conditions.
The color of sea water varies with the location. Near the shore, the water stirred up in the surf is more greenish, but way out to sea, deep water is more dark blue.
Clear sea water is intrinsically blue.* The thicker the observed sample is, the bluer it looks. In smaller water basins, like tap water bath's and swimming pools, water appears colorless.* Related Information:The blue color is caused by selective absorption of infrared spectrum of the sun light.Water doesn't derive its color from the blue sky. However, without sunlight water can't be seen as blue.Impurities dissolved or suspended in water may give water different colored appearances, which is more often the case in sea water and lower lakes (greyish brown) than is ice lakes higher in the mountains (blue).(cf. Related links for further detailed explanation on 'Why is water blue')This has nothing to do with the blue sky color:*The sky appears blue because blue light has a shorter wavelength than green and red light (blue light - 700nm, red light 400nm). Very small molecules in the atmosphere scatter blue light, where as green and red light passes straight through and we do not see it.
Sea water appears greenish-blue due to the absorption and scattering of sunlight by water molecules. Water molecules selectively absorb longer-wavelength colors like red and yellow, leaving shorter-wavelength colors like blue and green to dominate the reflected light. The presence of phytoplankton and algae in the water can also contribute to a greenish hue.
Sea foam is white.
Sea blue maybe gold or maybe a sea green
If you are referring to the different depths of blue and green, it is because the deeper the water is, the darker the color. The reason for this is because the deeper the water, the less sunlight can penetrate through to the floor and reflect back out.
In Greek mythology, Poseidon's eyes are commonly described as blue, reflecting his connection to the sea and water.