From NPR.

Around the world, coral reefs are suffering from the worst bleaching event on record, with 84% of the planet’s reefs affected, from Florida to Fiji.

Coral reefs are brightly colored due to algae living symbiotically inside them, but when oceans are too warm, the algae release toxins, causing the coral to kick them out, turning reefs white.

Last year was the earth’s hottest on record, driven by the burning of fossil fuels.

According to the International Coral Reef Initiative, the current bleaching event started in early 2023, and it’s unknown when it will end. Coral can recover from bleaching if ocean temperatures drop soon, but bleaching is often deadly.