The leading cause of coral bleaching is climate change.
A warming planet means a warming ocean, and a change in water temperature (as little as 2 degrees Fahrenheit) can cause coral to bleach, through driving out its algae, and die as a result. Coral may bleach for other reasons, like extremely low tides, pollution, or too much sunlight.
Once reefs die, they rarely come back, which is causing entire reef ecosystems to deteriorate. Both people and wildlife depend on these reef ecosystems, which are some of the most biodiverse and vibrant ecosystems on our planet.
pathways:
04.04.2022 / WWF /Everything You Need to Know about Coral Bleaching—And How We Can Stop It
14.03.2022 / NASA / Great Barrier Reef Mass Bleaching Event