Blue Waters of Paradise Beach Libya

The waters of the Mediterranean appear incredibly blue for a couple of reasons. First, oceans in general appear blue because blue is the wave length of light that penetrates water the most while the other colors are  absorbed. This blue wavelength is then scattered by particles, ripples, and oxygen in the water. Second, the bright blue mediterranean sky is also reflected to the observer making the water appear even more blue. Third, the Mediterranean ocean does not contain enough nutrients to support large amounts of algae that can tint the water green due to yellow pigments that they release when decaying. Close to shore in Libya, dissolved minerals from the eroding sandstone shores can give the water contrasting areas of bright turquoise.

Some good links to explore on this topic:
http://www.letusfindout.com/why-do-ocean-appears-blue/
http://www.bluesci.org/wordpress/wp-content/uploads/2011/pdfs/BlueSci-Issue3.pdf
http://en.wikipedia.org/wiki/Color_of_water
http://inside.mines.edu/fs_home/dwu/classes/CH353/study/Why%20is%20Water%20Blue.pdf