OCEAN · MARINE HEATWAVES & CORAL BLEACHING

Marine Heatwaves & Coral Bleaching

A live map of coral-bleaching heat stress — how much accumulated heat the world’s reefs are under right now, shown as NOAA’s Degree Heating Weeks. The headline climate-ocean signal: at about 4 degree-heating-weeks significant bleaching becomes likely; by 8, reef-wide bleaching and death. Warm colours over the tropics mark reefs being cooked. Updated daily from a global 5 km satellite product.