Great Barrier Reef: Severe coral bleaching hits two-thirds of reef, aerial surveys show

Updated

Two-thirds of the Great Barrier Reef has now been devastated by severe coral bleaching, with the most intense damage occurring further south this year, Queensland scientists say. “The sooner we take action on global greenhouse gas emissions and transition away from fossil fuels to renewables, the better.”

Almost 800 coral reefs across 5,000 miles were assessed by the Australian Research Council’s Centre of Excellence for Coral Reef Studies. "This is the fourth time the Great Barrier Reef has bleached severely – in 1998, 2002, 2016, and now in 2017," James Kerry, who was also involved in the aerial surveys, said. Now this year, researchers with the ARC Centre of Excellence for Coral Reef Studies at James Cook University in Queensland, who reported the previous findings, say that the reef's central sector has been hit by another year of damaging warmth. “It takes at least a decade for a full recovery of even the fastest growing corals, so mass bleaching events 12 months apart offers zero prospect of recovery for reefs that were damaged in 2016.”

READ MORE: Australia’s Great Barrier Reef on brink of collapse - scientists

The study found that while the northern third of the reef experienced the most severe bleaching last year, the middle third experienced the most intense coral bleaching this year, resulting in catastrophic damage of the natural wonder of the world. "The combined impact of this back-to-back bleaching stretches for 1,500 km (900 miles), leaving only the southern third unscathed," Terry Hughes, director of the Australian Research Council's (ARC) Centre of Excellence for Coral Reef Studies, said in a statement. While the 2016 bleaching event was in part due to El Niño conditions, this year's bleaching is due to record-breaking temperatures driven by global warming, according to Hughes, who undertook the aerial surveys in both 2016 and 2017. Sorry, this video has expired Video: Footage shows areas of the Great Barrier Reef in the Whitsundays devastated by Cyclone Debbie (ABC News)

Search for unspoiled reefs

Mark Read, the Great Barrier Reef Marine Park Authority's manager of species conservation, said it the authority was working with tourism operators to find reefs that had not been affected by bleaching. As temperatures continue to rise the corals will experience more and more of these events: 1°C of warming so far has already caused four events in the past 19 years.”

“Ultimately, we need to cut carbon emissions, and the window to do so is rapidly closing.”
The Australian Research Council reports that two thirds of the Great Barrier Reef have suffered from severe coral bleaching, denoting a second consecutive year of severe bleaching.