Warming tropical waters are largely responsible, researchers say
Kristen Brown/ARC Centre of Excellence for Coral Reef Studies
Corals are in hot water.
Severe bleaching events are hitting coral reefs five times as often as in 1980, researchers report in the Jan. 5 Science.
Scientists surveyed 100 coral reef locations in tropical zones around the world, tracking each spot’s fate from 1980 to 2016. At first, only a few of the locations had experienced bleaching. But by 2016, all had been hit by at least one bleaching event, and all but six had suffered a severe event — defined as affecting more than 30 percent of corals in an area.
The median time between pairs of severe bleaching events has also decreased, the researchers found — it’s now just under six years, versus 25 to 30 years in the early 1980s. That’s not enough time for corals to fully bounce back before getting hit again.
Consistently higher tropical water temperatures, the result of climate change, are in part