When the temperature in the ocean becomes too hot, the algae may suffer from heat stress. This can lead to a decrease in their photosynthetic efficiency, slower growth rates, and even bleaching – a process in which the algae expel their symbiotic dinoflagellates (zooxanthellae) and turn white. If the temperature remains too high for an extended period of time, the algae may die off in large numbers, leading to disruptions in the marine ecosystem and potential declines in biodiversity.
