Because it absorbs the longer reddish wavelengths.
Links:
http://www.whyiswaterblue.com/
http://en.wikipedia.org/wiki/Color_of_water
http://www.webexhibits.org/causesofcolor/5B.html
Water appears greenish blue because its complimentary color red is absorbed by water molecules
The colour of the sea is greenish blue because of the reflection of the sky
The greenish blue color of a lake can be due to the presence of algae or phytoplankton in the water. These microscopic organisms contain pigments that give the water a greenish hue. Additionally, the reflection of the sky and surrounding vegetation can also contribute to the blue color of the water.
The sea water is a greenish blue colour, (The greenish colour comes from the abundant plankton that thrive within the water.)
When copper reacts with chlorine in water, a greenish-blue color is formed, which is due to the formation of copper(II) chloride.
turquoise
because of the wave lengths and the molecule attract it in to the water:) by roshed
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.
Amber.
teal is a four letter word for a greenish blue color ^_^
greenish blue
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.