Three-quarters of Indo-Pacific coral reefs face existential threat from rising seas

Researchers at Nanyang Technological University have issued a stark warning about the future of coral ecosystems across the Indo-Pacific, finding that approximately 76 per cent of reefs in the region face a critical threat from rising sea levels in the coming decades.

The study, which examined the adaptive capacity of coral reefs to keep pace with ocean level changes, reveals a troubling mismatch between coral growth rates and projected sea level rise. As seas rise, corals must grow upward to remain within the shallow, sunlit waters necessary for their survival. However, the research indicates that most corals cannot maintain growth rates sufficient to match ocean level increases exceeding 5.3 millimetres per year—a threshold increasingly likely under current climate projections.

The Indo-Pacific region, which stretches from the Indian Ocean to the central Pacific, contains some of the world's most biodiverse and ecologically significant coral reef systems. The findings underscore the urgency of climate mitigation efforts, as even coral species considered relatively resilient face mounting pressure from warming waters and changing ocean chemistry alongside rising sea levels.

Scientists emphasise that the window for preventing the most severe outcomes remains open but is rapidly closing. The research adds to mounting evidence that coral reef ecosystems globally face unprecedented challenges and require immediate action to reduce greenhouse gas emissions and protect remaining reef habitats.