Extended Bleaching Events Are Killing Corals As Oceans Warm

Rising ocean temperatures are intensifying the die-off of corals around the planet, according to U.S. government scientists. “We are currently experiencing
Bleached coral at the Great Barrier Reef
the longest global coral-bleaching event ever observed,” said Mark Eakin, head of Coral Reef Watch at the National Oceanic and Atmospheric Administration. Bleaching occurs when corals respond to environmental hazards, such as high ocean temperatures, by expelling the symbiotic algae they need to provide them with sustenance. Eakin predicted that the latest extended bleaching event, which started in 2014, will likely last well into next year, at which time about 60 percent of corals worldwide may be affected. Eakin compares the continuous pressure that reefs have been under in recent years to a boxing bout. “What used to be a one-round fight is turning into a two- and three-round fight,” he says.