February 26, 2016 — Rising global temperatures combined with an especially powerful El Niño are causing one of the biggest coral reef die-off events ever recorded.
The researchers, who are monitoring and forecasting offsite link the loss of corals from disease and heat stress due to record ocean temperatures, report that the global coral bleaching event that started in 2014 could extend well into 2017.
Approximately 500 million people worldwide depend upon reefs for food and to protect coastlines from storms and erosion. Coral reefs provide habitat, spawning and nursery grounds for economically important fish species; provide fishing, recreation, and tourism jobs and income to local economies; are a source of new medicines, and are hotspots of marine biodiversity. Reefs contribute approximately $29.8 billion to world economies each year. In the United States, NOAA Fisheries estimates the commercial value of U.S. fisheries from coral reefs is more than $100 million.
“We are currently experiencing the longest global coral bleaching event ever observed,” said Mark Eakin, NOAA’s Coral Reef Watch coordinator. “We may be looking at a 2- to 2½-year-long event. Some areas have already seen bleaching two years in a row.”
According to Eakin, the length of the event means corals in some parts of the world have no time to recover before they are hit by more bleaching. The current global bleaching event is hammering some reefs repeatedly.
Scientists first observed the current global coral bleaching event beginning in mid-2014, when bleaching began in the western Pacific Ocean. In October 2015, as the current El Niño was still strengthening, NOAA scientists declared the third global bleaching event on record was underway.
The NOAA coral scientists point out that reefs that bleached in 2015 in the Caribbean and Florida Keys have just started to recover, but may start bleaching all over again as early as July. Eakin also notes that in the Pacific, corals in Fiji’s nearshore waters are bleaching with lots of dead coral for the second consecutive year, and could be worse than last year.