As record heat risks bleaching 73% of the world’s coral reefs, scientists ask ‘what do we do now?’

A vast array of solutions are being worked on but experts urge a ‘fundamental rethink’ as temperatures are forecast to climb even higher in coming decades

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After 18 months of record-breaking ocean temperatures, the planet’s reefs are in the middle of the most widespread heat-stress event on record.

Across the Pacific, Atlantic and Indian oceans, latest figures from the US government’s Coral Reef Watch, shared with the Guardian, show 73% of the world’s corals have been hit with enough heat for them to begin bleaching.

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