Romantic Couples Dazzled by Glowing Blue Ocean Waves, the Cause May Surprise You

May 21, 2019 Updated: May 21, 2019

One may think of the gentle orange flame of tiki torches when imagining, or even remembering, a romantic evening walk along a beach. On some beaches, the soft orange is replaced by an enchanting, florescent blue glow—coming straight from the water.

The glowing blue lights up the shoreline as waves break, or as people splash through the shallows in the dark of night.

Blue ocean wave
A blue wave of sea sparkle. (Pear Videos)

While this watery glow is called “blue tears” in Chinese, it is called “sea sparkle” in English.

Every year, from April to August, sea sparkle can appear on the beaches in Pingtan County, China. There must also be a southern wind and high tide for people to see the huge blue blooms, according to Chinese online-news outlet Pear Videos.

“When you first see the blue tears, it’s just like stars in the sky,” a woman who shared footage of the waves told Pear Videos. “Then everyone says, ‘quick! they’re coming!'”

“The blue tears suddenly form into an entire breaking wave,” couples can be heard calling out in the video as the blue waves light up the water line for the crowd.

Blue ocean wave
A couple playing in the blue waves. (User: Pineapple’s Travel Diary/

This natural phenomenon has drawn young lovers to the southeastern shores of China, where the lights have become a spectacle for couples to share with each other, and even on social media.

Though sea sparkle can be seen in many waters around the world, the blue tears in Fujian Province has a special story, according to Pear Videos.

Blue ocean wave
A couple holding hands while they run through blue waves. (User: Pineapple’s Travel Diary/

Legend has it that the blue tears are from a mermaid princess, they represent a love story, the woman told Pear Videos. “Many couples will want to come out to see them, hoping their love can be long lasting.”

Perhaps most surprisingly, this light show is created by clusters of single-celled organisms, with the scientific name “Noctiluca scintillans.”

Sea Spark Noctiluca Scintillans
Credit: (Maria Antónia Sampayo, Instituto de Oceanografia, Faculdade Ciências da Universidade de Lisboa –[CC BY 3.0 (])
These sea sparkle is hardly unique to China. They can also be found on, and not limited to, both coasts of the United States, Europe, other Asian countries, and Australia.

Just like their scintillating night name, these organisms use bioluminescence—naturally produced light—as a defense mechanism. This same characteristic can be seen in fireflies (also called lightning bugs), certain kinds of fish, and even squid.