This story was originally published by Guardian and is reproduced here as part of the Climate Desk collaboration. 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 percent of the world’s corals have been hit with enough heat for them to begin bleaching. Beginning in February 2023, this is the fourth global mass bleaching event—the second in 10 years, and the most widespread on record. After seeing their beloved reefs struggling to survive, some coral scientists are now calling for a major rethink on how to protect reefs as temperatures climb even higher in the coming decades.