Glowing Waves Appear at Southern California Beaches

Category: Science/Environment


Unlocking Word Meanings

Read the following words/expressions found in today’s article.

  1. bioluminescent / ˌbaɪ oʊˌlu məˈnɛs ənt / (adj) – producing light by a living organism

    Fireflies and jellyfish are bioluminescent.

  2. emit / ɪˈmɪt / (v) – to produce something (e.g. light, energy)

    Motor vehicles emit pollutants like carbon dioxide.

  3. defense mechanism / dɪˈfɛns ˈmɛkəˌnɪzəm / (n) – a reaction against a possible danger

    Some animals use defense mechanisms to survive.

  4. predator / ˈprɛd ə tər / (n) – an organism that hunts, attacks, or kills another

    Small animals have many predators.

  5. bloom / blum / (n) – a rapid growth in the population of plankton or marine organisms such as jellyfish

    Beachgoers find the jellyfish bloom alarming.


Read the text below.

Microscopic plants illuminated San Diego waves as beaches reopened in California.

Beachgoers witnessed the glowing neon waves at night caused by bioluminescent phytoplankton called L. poly. The phenomenon happens from time to time on the beaches of southern California. However, locals say that the waves this year are considered to be the most vibrant in a decade.

According to the Scripps Institution of Oceanography, the phytoplankton emit light as a defense mechanism against predators.

A report by the Southern California Coastal Ocean Observing System (SCCOOS) revealed that beaches in the area have been experiencing a prolonged marine heatwave for the last five years. The warmer temperatures of the ocean caused the phytoplankton to reproduce rapidly. While some phytoplankton blooms produce harmful toxins, L. poly are harmless and non-toxic to humans.

Blooms can last from a few days to a few months, and the phytoplankton bloom in San Diego has already been visible for over three weeks.

California reopened beaches after a month-long closure due to the Covid-19 pandemic. Social distancing measures have been introduced, so people can stay safe while visiting beaches.

With a lot of visitors coming to the beach to witness the bioluminescent attraction, one San Diego resident expressed concern that social distancing measures are not being properly followed. The resident has complained about the large number of people on the beach and has asked authorities to limit the number of people there at one time.

Viewpoint Discussion

Enjoy a discussion with your tutor.

Discussion A

• How would you react if you saw bioluminescent beach waves? Why?
• If you saw bioluminescent waves at the beach, would you go in the water? Why or why not?

Discussion B

• How can authorities control the number of people who come to see the bioluminescent waves? Discuss.
• Do you think bioluminescent waves are related to global warming? Explain.