For decades, coral reefs throughout the Caribbean have been suffering from disease, pollution, overfishing and rising sea temperatures, yet most have continued to grow – until now.

In 2023 and 2024, surface temperatures climbed to record highs in the world’s oceans, and a marine heatwave of unprecedented length and intensity spread across the tropics. Satellites from the US National Oceanic and Atmospheric Administration detected heat stress that could cause corals to bleach across more than 80% of the planet’s reef areas.

During these periods of extreme stress, corals expel the symbiotic algae that give them their colour and most of their food – turning them stark white and leaving them vulnerable to starvation, diseases and eventually death.

Across the North Atlantic, including the Caribbean, the heat stayed for months, with heat stress two-to-three times higher than reefs had ever experienced. Heat stress, the phenomena of high temperatures putting fragile ecosystems under pressure, can permanently alter their ability to function.

This triggered what is now recognised as the fourth global coral bleaching event, the most severe one that has been documented.

Coral reefs are among the most productive ecosystems on Earth, and their importance to people is fundamental. They feed hundreds of millions through small-scale fisheries, underpin tourism across the Caribbean, and serve as natural breakwaters that protect the coast from storms and........

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