New findings about record heat in the Coral Sea around the Great Barrier Reef add fuel to the debate about whether the natural wonder should be classed as endangered. Large chunks of the reef have now lost their colourful display due to coral bleaching events driven by climate change.
Temperatures on the Great Barrier Reef have soared to their highest in 400 years, a new study has found.
It said the “unprecedented” heat on the sea surface around the natural wonder is driving increasingly frequent mass bleaching events that are putting it in danger.
Without stronger and faster action to tackle climate change, our generation will “likely be witness to the demise of one of Earth’s great natural wonders”, according to the paper, published today in the peer-reviewed journal Nature.
The Great Barrier Reef is the world’s largest coral reef system and gives life to diverse species, from whales and dolphins to 1,500 types of fish and endangered turtles and dugongs.
It was listed as a UNESCO World Heritage Site in 1981 and it helps attract major tourism to Australia.
But its health has been at the heart of tensions between Canberra and the world heritage body.
Waters have been so warm in recent years that stressed corals – which are the backbone of the reef – expelled the colourful, symbiotic algae that live inside them, hence the term “bleaching”.
The Australian government has fiercely resisted a feared downgrade of the reef by UNESCO to “in danger”, amid concerns about the impact on tourism and consequent pressure to take stronger climate action, and efforts to better protect it.
The researchers hope UNESCO will reconsider its recent decisions to keep the reef off the endangered list.
Professor Ove Hoegh-Guldberg from Queensland University said UNESCO’s assessment was “now beyond credibility”.
Lead author Dr Ben Henley, from Australia’s Wollongong University, said their study provides “new evidence” since UNESCO’s last determination that the reef isn’t yet in danger.
“We hope they look at that evidence and that that mechanism can be used to spur more action on climate change, and also local protection of the reef,” he said.
Professor Helen McGregor, also from Wollongong University, said a reassessment of the coral’s health “should potentially be extended to all World Heritage-listed reefs by UNESCO, because they are all in danger from global warming.”
She called it the “coral in the coal mine”.
“This is one of our early warnings that things are not right,” she added.
UNESCO was not immediately available to comment.