Pacifica's beaches are captivating many with bioluminescent glow-in-the-dark waves, a sight that's almost too eerie to believe.
The electric blue glow is caused by an algae bloom commonly referred to as a “red tide.” The microscopic, red algae, a phytoplankton called Lingulodinium polyedrum, has bloomed since late August, turning the water a brownish-red color in the daytime.
The color is caused by a chemical reaction that results from the movement of the algae. Move a whole lot of algae at once and a brilliant flash of light becomes visible.
How much longer the blue surf will last is unknown. Plumes of the brownish-red water can still be seen drifting up and down the coast with the ocean currents.
Red tide is not generally dangerous but can cause certain respitory irritations in some people such as surfers and ocean swimmers who breathe the air close to the surface of the water, according to U.S. Ocean Safety officials. Red tide also contributes to levels of toxicity in shellfish, which filter the ocean water through their bodies to feed on microscopic ocean life. It can smell bad, too.
Still, it's the greenish glow of phosphorescence that makes a red tide so extraordinary (and bearable for those who don't like surfing in it). The brilliant light show of turquoise glowing waves breaking along the shoreline at night is a sight to behold.
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