Glowing Blue Waves Reported Across Southern California Coast Due to 'Red Tide' Phenomenon

Bioluminescent blue waves are being reported at night from Los Angeles all the way down to Baja California in Mexico.

The strange phenomenon is the result of a massive bloom of phytoplankton—microscopic marine algae that produce their own food via photosynthesis—in the waters of the Pacific known as a "red tide," scientists say.

According to bioluminescence expert Michael Latz from the Scripps Institution of Oceanography at the University of California San Diego, red tides are caused by large aggregations of a type of single-celled phytoplankton called Lingulodinium polyedra, which are neither animals, plants nor fungi.

These microscopic organisms contain pigments that give them a reddish-brown color, which protect them against the harmful effects of the sun's rays. When the sun is out, the phytoplankton swim towards the surface of the water, giving it a reddish-brown appearance.

However, at night, the phytoplankton—which belong to a group of organisms known as "dinoflagellates"—emit a bright neon blue glow when they are agitated by waves or movement in the water. According to Latz, the organisms emit the light as a strategy to deter certain predators.

SURF'S UP: Surfers in California rode stunning, bioluminescent waves off the coast of San Diego. The remarkable sight was caused by a red tide—typically caused by a bloom of a type of plankton—that stretched up a part of the coast.

— ABC News (@ABC) May 3, 2020

Red tides as a result of L. polyedra have been documented since the early 1900s in California. However, the phenomenon is unpredictable and they don't appear regularly in the region.

Furthermore, it is not clear how long the current bloom—which reportedly began at the end of March—will last, with previous events enduring for days, weeks or even months. The blooms can also vary significantly in size.

bioluminescent waves, California
A lifeguard tower is seen as bioluminescent waves crash on the sand, shining with a blue glow on April 28, 2020, in Manhattan Beach, California. VALERIE MACON/AFP via Getty Images

"It's just pretty spectacular," Venice resident Paige Taylor told CBSLA. "I've seen it maybe once every five years."

While red tides are unpredictable, Latz says that they are increasing in frequency around the world, as well as in the U.S. While scientists still don't fully understand all of the factors that result in these events, experts that climate change could play an important role.

@SCCOOS_org PI, Raphe Kudela, and colleague, Alexis Fischer, from UCSC answer @Surfer questions about the current Red Tide we are experiencing in Southern California

— SCCOOS (@SCCOOS_org) May 1, 2020

Red tides can be caused by three types of microscopic, photosynthetic algae—dinoflagellates, cyanobacteria and diatoms. They occur when colonies of these organisms grow out of control, sometimes producing toxins that can have a harmful effect on ecosystems, marine life and even humans.

Some people, for example, appear to be sensitive to inhaling air surrounding a red tide caused by Lingulodinium polyedra. However, not algal blooms are harmful, according to the National Ocean Service. In fact, they are often beneficial in the sense that they provide food for marine life.