Record Coral Bleaching Hits 84% of World's Reefs

A sweeping coral bleaching crisis has reached historic levels, affecting 84% of reefs around the world. And there's with no clear end in sight, say scientists, who warn the event could forever alter ocean life and the communities that depend on it. International Coral Reef Initiative, a group of more than 100 governments and non-governmental organizations, described the record coral bleaching event on Wednesday, per the AP, noting it is the most intense event of its kind in recorded history. It is the fourth global coral bleaching event since 1998. The current crisis began in 2023 and is blamed on warming oceans; it's unclear when it will end. It has surpassed the 2014-2017 event, which hit about two-thirds of reefs.

NOAA's Coral Reef Watch has tacked on new levels to its bleaching alert scale to account for the greater risk. The average annual sea surface temperature outside the polar regions reached a record 69.57 degrees Fahrenheit or 20.87 degrees Celsius last year. These temperatures are deadly to coral reefs, which support about 25% of all marine species and are also important for seafood production, tourism, and coastline protection. Bleaching occurs when warm temperatures cause algae to release toxins. Corals expel the algae, lose their color, and face a higher risk of dying. Surveys indicate widespread coral death, per the Guardian.

"We're looking at something that's completely changing the face of our planet and the ability of our oceans to sustain lives and livelihoods," said Mark Eakin, executive secretary for the International Coral Reef Society, noting the heat stress that causes bleaching may now be a permanent thing. "The best way to protect coral reefs is to address the root cause of climate change. And that means reducing the human emissions that are mostly from burning of fossil fuels," he said. However, Eakin noted "we've got a government right now that is working very hard to destroy all of these ecosystems"—an apparent reference to President Trump's stripping of marine protections. (This content was created with the help of AI. Read our AI policy.)