Catastrophic Risk: Extreme Ocean Temperatures Threaten Global Reefs

05.07.18 By
This content is more than 5 years old

THE GREAT BARRIER REEF could be hit with catastrophic bleaching every two years by 2034, under current greenhouse gas pollution levels, according to the latest report from the Climate Council.

The ‘Lethal Consequences: Climate Change Impacts on the Great Barrier Reef’ report shows the future survival of coral reefs around the world, including the Great Barrier Reef, depends on how deeply and swiftly greenhouse gas pollution levels are slashed over the coming years and decades.

Climate Councillor and ecologist Professor Lesley Hughes said accelerating climate change has driven a 54 per cent increase in the number of marine heatwave days each year (between 1925-1954 and 1987-2016), placing global reefs at serious risk.

“Intensifying marine heatwaves around the world are now occurring more often, lasting longer and are more intense than ever before,” she said.

“Now, coral reefs around the world are also in the firing line, with rising ocean temperatures and more frequent marine heatwaves placing them at increasing risk.”

Professor Hughes said the unprecedented bleaching events on the Great Barrier Reef in 2016 and 2017 resulted in mass coral mortality, with the 2016 bleaching event at least 175 times more likely to occur due to intensifying climate change.“Unless drastic action is taken, extreme coral bleaching will be the new normal by the 2030s. We will see extreme ocean temperatures, similar to those that led to these bleaching events possibly occurring every two years, which will effectively sign the death certificate for the world’s largest natural living wonder that is the Great Barrier Reef,” she said.


Climate Council Acting CEO Dr Martin Rice said the future of coral reefs around the world depends on nations including Australia doing their part to effectively tackle climate change.

“Limiting global temperature rise above pre-industrial levels to no more than 1.5°C is critical for the survival of reefs worldwide, along with economies and tourism operators who rely upon them,” he said.

“We cannot place our heads in the sand as marine heatwaves intensify due to the burning of fossil fuels such as coal, oil and gas around the world.”

“This report shows that the Great Barrier Reef may never fully recover or return to its pre-bleaching state, which should serve as a serious warning signal for Governments around the world to act now.”  

“We all have a part to play in cutting greenhouse gas pollution levels in order to protect these natural wonders. The only thing standing in the way is political will.”

For more information please contact Senior Communications Advisor Alexia Boland on 0438 972 260.

The Climate Council is Australia’s leading climate change communications organisation. We provide authoritative, expert and evidence-based advice on climate change to journalists, policymakers, and the wider Australian community.

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