Ocean luminescence is caused by large luminous organisms in the ocean, such as jellyfish, sponges, liverworts, ring worms and shellfish. Jellyfish have special light-emitting organs on their bodies, which emit great flashes when stimulated. Some fish can secrete a special substance, which reacts with oxygen to emit light. This luminous creature usually appears in isolation, which is more noticeable under the stimulation of mechanical and chemical substances. The sea light they emit is characterized by one bright and one dark, which circulates repeatedly, like a flashlight. This ocean glow is called flash ocean glow.

Hai Xia is not only colorful, beautiful and attractive, but most importantly, it is closely related to production and construction.

The sea area with strong sea light can reflect the sea view at night, so when a ship encounters sea light at night without moonlight, it will make the captain have an illusion, lead to an average accident and affect the safe navigation of the ship. Correctly mastering Haihui can predict the weather. After years of observation, fishermen in Hebei and Liaoning provinces of China summed up a folk proverb: "See the fire at sea, see the wind and rain." The sea light produced by fish swimming exposes the hiding place of fish, so experienced fishing boat captains use it to fish at night.