Mass Coral Reef Extinction

Mass coral reef extinction is the most immediate, visible tipping point in the climate crisis. At 1.5°C of warming, 70–90% of tropical coral reefs are projected to die; at 2°C, that figure surpasses 99%, a collapse far outpacing the average extinction risk for terrestrial ecosystems. This would devastate the livelihoods of 500 million people, a number 2.3 times larger than the projected climate migrants by 2050. The threshold is so stark that #10 (Economic Losses from Climate Change) often underestimates long-term fisheries revenue tied to reef health. Unlike any other climate effect, reef loss creates a direct, irreversible loss of biodiversity in under three decades.