Tropical coral reefs cover less than 1% of the seafloor, yet support 25% of all marine species. They are also incredibly vulnerable. Over the past few decades, an estimated 30%-50% have already been lost.

Yet we are approaching a terrifying threshold. After record-breaking ocean heatwaves of 2023-24, which saw coral “bleaching” in at least 83 countries, scientists are looking towards 2026 with growing dread.

The question is whether this will be the year a global tipping point is reached for warm-water coral – a point beyond which their fate is sealed, and even the most resilient species can no longer recover.

The fate of these ecosystems may hinge on events in the Pacific Ocean, in particular a natural climate cycle called the El Niño–Southern Oscillation (ENSO). We have only just emerged from a devastating El Niño (the warm phase) that helped push 84% of the world’s coral reefs into “bleaching-level” heat stress.

Usually, reefs have a few years to “breathe” during the cooler La Niña phrase. However, as the planet warms El Niños are becoming stronger and more frequent, and the transition periods are becoming shorter and less cool.

With another El Niño expected in 2026, only a short time after the last one, many reefs will not have had sufficient time to recover. This next phase could trigger widespread coral reef collapse.

The fear is that 2026 could mark a “tipping point”. These are moments when an ecosystem changes really suddenly, often in a........

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