In May 2018, the waves along 18 miles of the San Diego coast began breaking upon the shore with a beautiful vivid blue color that seemed to come out of nowhere. As it turns out, this neon color is created by an overabundance of bioluminescent planktonic dinoflagellates, the same type of algae that behind the less attractive “red tide”, but set off pretty colors whenever they are disturbed.
Red tides are conditions when a dinoflagellate population increases to such huge numbers that it discolors the water. This “bloom” may be caused by nutrient and hydrographic conditions …For dinoflagellate red tides, the water is discolored red or brown due to as high as 20 million cells per liter. These red tides are composed primarily of one species of dinoflagellate that has been rapidly growing and accumulating. Some red tides are luminescent; most in southern California create dramatic nighttime displays of bioluminescence in the wakes breaking on the beach
A number of people posted amazing photos of this beautiful phenomenon.