The sea appears blue because of how the sea water absorbs sunlight. The sea water absorbs long wavelengths that are made up of red, orange and yellow more strongly than blue which has a short wavelength. When sun rays hit the sea, blue colours gets reflected and that's what we see. This only happens when the water us clean. Although some argue that the sea is blue because the sky is blue so invariably the sea is reflecting the colour of the sky.
The sea appears blue because of how the sea water absorbs sunlight. The sea water absorbs long wavelengths that are made up of red, orange and yellow more strongly than blue which has a short wavelength. When sun rays hit the sea, blue colours gets reflected and that's what we see. This only happens when the water us clean. Although some argue that the sea is blue because the sky is blue so invariably the sea is reflecting the colour of the sky.