Global Coral Bleaching: 84% of Reefs Hit
Why in the news
The International Coral Reef Initiative said bleaching has hit most of the world’s reefs, the worst episode on record, driven by ocean warming.
Key facts
- 84% of coral reefs affected, the most intense global bleaching event recorded; started in 2023.
- It exceeds the 2014-2017 event that hit two-thirds of reefs, and is the fourth global event since 1998.
- 2023-2024 was Earth’s hottest year, with ocean surface temperature averaging 20.87°C.
- Reefs support about 25% of marine species and are called the “rainforests of the sea”.
How bleaching happens
- Corals expel the colourful algae that feed them under prolonged heat, leaving white skeletons prone to death.
Challenges
- Mark Eakin (International Coral Reef Society) warned heat stress may never fall below the level needed to end the crisis.
Responses
- Lab restoration of coral fragments (a Dutch lab with Seychelles corals) and Florida rescue projects.
- Melanie McField (Global Coral Reef Monitoring Network): cutting CO2 and methane is the best long-term fix; inaction would be a “kiss of death”.
Exam angle
- Body: ICRI; 84% reefs, fourth event since 1998.
- Reefs aid tourism, seafood and coastal protection.