?Why is the sea blue

Why is the sea blue?
Really, why is the sea blue? Good friend Benj Arriola wrote a very nice piece on why the sky is blue and I do have to say that everything he has to say about the color of the sky is pretty much accurate. However, he did mention that the sea is blue because of the sky. While this is partially true, it is not entirely correct and so I decided to write this blog post to answer the question of the why the sea is colored blue.
Before I proceed, allow me to quote a small section from Benj’s blog post which says, “We know why the water in the ocean and at sea is blue but water in your hands or in a glass has no color. It is simply the reflection of the sky.” As I said previously, though the sky do have some part in giving th sea its color, this statement is not entirely correct.
So why is the sea blue? There are two reasons..
First answer is what Benj said. The sea reflects the sky. You have probably noticed that the sea is not very blue-looking when the sky is overcast. Water reflects and scatters the light that strikes it; this is shown by the fact that you can see your reflection in puddles. When the sky is brilliant blue, the sea is also, because it reflects the blue of the sky. Note however that the sea is still blue though not so brilliant even if the sky is gray. In other words, something else is at work here.
The second reason is exactly the same reason on why the sky is blue. Blue light is more easily bent, or refracted, than red light; thus, light refracted back from the surface of the sea appears blue. Furthermore, when you are underwater the water around you appears blue because more blue light is scattered back to your eye than red light.
The reflection part is most effective on surface to near-surface water only. However, as I said, it is not the only reason. Try putting a glass of water under the sky and you will notice that it is not really that blue. Also, you may have already seen green sea water under the bright blue sky.
Now, here’s the funny part. If we talk about the sky, it slow turns from blue to violet to black as one flies out into outer space. The changing of hues also applies to the sea. The deeper the sea is, the bluer it becomes. For deeper seas, the blue color is given by the penetrating sunbeams. When a sunbeam hits the water surface, it doesn’t stop its course at once, but splits into different hues as it goes deeper. The color yellow disappears along the first meters, then the red fades, and finally the green. The only color left is blue.
Shallow waters on the other hand can only give off a light blue and sometimes even green but deeper waters give off a deeper blue color and if you go diving deep enough, you will be surprised that the surrounding color turns black as sunlight can no longer penetrate it.
Now, before I end this post… I wish to add another factor to the color of the sea and it is the material that can be found under the sea such as corals, sand, sea grass, etc.
Ok. Now before you say that I am trying to put shame on Benj’s face, I would like to tell you that I’m not. I’m simply adding more color to what he wrote which by the way is still a lot more amazing than this.