Scientists in the U.S. have announced Monday that a mass bleaching of coral reefs worldwide has finally ended after three years. "About three-quarters of the world's delicate coral reefs were damaged or killed by hot water in what scientists say was the largest coral catastrophe," reports Phys.Org. From the report: The National Oceanic and Atmospheric Administration announced a global bleaching event in May 2014. It was worse than previous global bleaching events in 1998 and 2010. The forecast damage doesn't look widespread in the Indian Ocean, so the event loses its global scope. Bleaching will still be bad in the Caribbean and Pacific, but it'll be less severe than recent years, said NOAA coral reef watch coordinator C. Mark Eakin. Places like Australia's Great Barrier Reef, northwest Hawaii, Guam and parts of the Caribbean have been hit with back-to-back-to-back destruction, Eakin said. University of Victoria, British Columbia, coral reef scientist Julia Baum plans to travel to Christmas Island in the Pacific where the coral reefs have looked like ghost towns in recent years. While conditions are improving, it's too early to celebrate, said Eakin, adding that the world may be at a new normal where reefs are barely able to survive during good conditions.