why is the sea blue?

Answer 1

The water mollecule has vibrational resonances in the infrared (and slightly into the visible red), so it gives water a very slight bluish tint when light shines through it. Also, when you are looking at the ocean, you are looking at reflected sunlight which was scattered from the atmostphere. Blue light gets scattered by the atmosphere more than red (see the "why is the sky blue?" questions), so the oceans look blue mostly because they are reflecting the blue light from the sky.

Answer 2

There are two reasons for the color of the sea; both of them contribute to the answer.


A. 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. A good answer to why the sky is blue has already been posted at MADSci.

B. The sea refracts light just as the sky does.
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. Here are some professional shots to show what I mean.
The scattering of light by the air, or by water, is called Rayleigh scattering.

Answer 3

Very simple answer - it isn't! If you only see blue sea, you aint been anywhere and you're seeing only movies or painted pictures. The sea is a mirror that reflects the sky and the atmosphere in general. You will never see blue sea when the sky is overclouded - don't confuse sea with some lakes in the world that are actually coloured blue by metals or plants.
Beyond DAve

Answer 4

Because of the large amounts of ions and the such like (im not sure which but could probably find out), which when dissolved have the natural colour blue.

What makes it really bright, vibrant blue is when the sun heats up the water, increasing the vibrational frequency and so making it a different colour, hence why in the Cariibean and other hot parts of the world, the sea is a much brighter blue.

In places like SCotland, however, there is less heat from the sun absorbed in the water, meaning that there is less vibrational frequency and so on... you get my meaning.

Answer 5

The sea does not always appear blue. It reflects the colours in the sky and any high cliffs on the shore.

Answer 6

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.

Answer 7

Because water, although appearing to be clear, has a very slight bluish tint to it.

You would have to have a lot of water to see the blue tint clearly.

Since the sea is in effect a very large body of water, the tint is more easily recognisable.

Answer 8

Well becuase water is natrually that clearish lihgt blue color and the ocean is deep so that's why it's usually a dark blue and the sky is blue too so they kind of reflect off of each other.

Answer 9

if im not mistaken i remember hearing that teh sea is blue because the sky is reflected on the water so teh sky being blue the color reflects on the sea.so the sea refracts the light from the sky..
hoped it help

Answer 10

The sky is reflected in it and the sky is usually blue. Also it turns out that water does have a tiny amount of natural color to it and that is blue.