Intensity of exposure ratio for algae at aug - sep 1997:
1997, 13.aug - 13.sept
As has already been said by TheBeast this underwatercolor changes then with the daylight, oceandepth, your actual diving depth, etc...
- The more clouds => the darker
- The lower the sun => the darker
- The deeper the ocean => the darker
- The deeper you dive => the darker
- The more algae => the greener
And one thing must be also clear, when the time/season will change then this colorszone-areas and the color will also change. This distribution of colours are pretty much accurat for aug-sept but not for jan-feb for example.
Bet at night, with no moon you can see only a black surrounding and your visibility is about 2 or 3 meters.