Two-thirds of Australia’s Great Barrier Reef has recorded the greatest coral cover in nearly four decades, a development hailed around the world but which should not obscure the reef’s vulnerability to climate change and mass bleaching.
In the central and northern regions, hard coral cover has reached 33% and 36% respectively this year, the highest levels recorded in the past 36 years of monitoring, the Australian Institute of Science said this week. marines, a government agency.
Yet hard coral cover on the southern reefs has fallen to 34% this year from 38% the previous year.
The Great Barrier Reef, rich in wildlife and popular with tourists, has suffered widespread and severe bleaching due to rising ocean temperatures. The reef was heavily damaged in 2016 and 2017 by underwater heat waves made worse by climate change.
The reef provides $6.4 billion a year to the economies of Queensland and Australia and supports 64,000 jobs in fishing, tourism and more, according to the Great Barrier Reef Foundation. The Australian government has spent on its restoration.
The Great Barrier Reef, so vast it can be seen from space, is made up of 2,900 distinct reefs and 900 islands. It struggles to recover when there is not enough time between bleaching events.
“The reef is now experiencing widespread bleaching damage at the rate of more than once every two years,” Richard Leck, Oceans Australia manager for the World Wildlife Fund (WWF), said earlier this year.
“Coral bleaching is directly attributable to climate change caused by increasing global greenhouse gas emissions. Rapidly reducing Australia’s domestic and exported emissions this decade is the key solution within our control,” he said.
Paul Hardisty, CEO of the marine institute which published the findings this week, said the results in the northern and central regions were a sign that the reef could still recover, but the loss of coral cover in the southern region showed how dynamic the reef is. The heat disturbance, for example, has caused an outbreak of crown-of-thorns starfish.
Hardisty said the increase in the frequency of mass coral bleaching events was “uncharted territory” for the reef, with this year’s bleaching event being the fourth in seven years and the first to occur during a La Niña cooling.
Still, some social media responses Friday to the news argued that the data belies the idea that climate change won’t allow the Earth to regenerate.
UNESCO proposed last year to add the Great Barrier Reef to the list of World Heritage Sites in Danger. A meeting to discuss the future of the reef was due to be held in Russia in June, but was canceled after the invasion of Ukraine.