Technology & Science

Mass bleaching in Great Barrier Reef kills huge swaths of coral

Mass bleaching has destroyed as much as 35 per cent of the coral on the northern and central Great Barrier Reef, Australian scientists said on Monday.

Up to 35 per cent of coral on northern and central part of reef is dead or dying

Scientists say almost 35% destroyed by bleaching 0:34

Mass bleaching has destroyed as much as 35 per cent of the coral on the northern and central Great Barrier Reef, Australian scientists said on Monday. That's a major blow to the World Heritage Site that attracts about $5 billion in tourism each year.

 Australian scientists said in March just seven percent of the entire Great Barrier Reef had avoided any damage as a result of bleaching, and they held grave fears particularly for coral on the northern reef.

This April, 2016 photo released Monday, May 30, 2016 by ARC Centre of Excellence for Coral Reef Studies, shows mature stag-horn coral dead and overgrown by algae at Lizard Island, Great Barrier Reef off the eastern coast of northern Australia. The reef studies center released the results of its survey of the 2,300-kilometer (1,430-mile) reef off Australia's east coast on Monday. (David Bellwood/ARC Centre of Excellence for Coral Reef Studies via Associated Press)

After further aerial surveys and dives to access the damage across 84 reefs in the region, Australian scientists said the impact of the bleaching is more severe than they had expected.

Bleaching occurs when the water is too warm, forcing coral to expel living algae and causing it to calcify and turn white. Mildly bleached coral can recover if the temperature drops, otherwise it may die.

 Although the impact has been exacerbated by one of the strongest El Nino weather systems in nearly 20 years, which recently subsided, scientists believe climate change is the underlying cause.

This February, 2016 photo released Monday, May 30, 2016 by ARC Centre of Excellence for Coral Reef Studies shows mature stag-horn coral bleached at Lizard Island, Great Barrier Reef off the eastern coast of northern Australia. Some parts of the reef had lost more than half of the coral to bleaching. (David Bellwood/ARC Centre of Excellence for Coral Reef Studies via Associated Press)

This year is the third time in 18 years that the Great Barrier Reef has experienced mass bleaching due to global warming, and the current event is much more extreme than we've measured before said professor Terry Hughes, director of the ARC Centre of Excellence for Coral Reef Studies at James Cook University.

But Australian Prime Minister, Malcolm Turnbull defended the country's management of the reef, adding that the World Heritage Committee decided last year not to put the Great Barrier Reef on the endangered list because of Australia's management of it.

"So there is no question that we are doing a good job," he said.

UNESCO's World Heritage Committee last May stopped short of placing the Great Barrier Reef on an "in danger" list, but the ruling raised concern about its future.

Omitted from UNESCO report

The new survey findings come just days after Australia's Department of Environment confirmed it omitted its contribution to a U.N. report examining the impact of climate change on world heritage sites over concerns it could create "confusion" and have a negative impact on tourism.

 Australian Opposition leader, Bill Shorten pledged A$500 million ($469 million) on Monday to further protect the reef.

In this June 25, 2015 photo, scuba divers prepare to dive to the Great Barrier Reef, in Australia. The World Heritage Site that attracts about $5 billion in tourism each year. (Wilson Ring/Associated Press)

"This will be the single largest and indeed most overdue injection of funds to save the Great Barrier Reef," he said. "The Barrier Reef is in great peril, we see the effects of climate change, we have a government currently in Canberra, who despite Mr. Turnbull's protestations is not acting on climate change."

 The World Heritage and Tourism in a Changing Climate report, which was released on Friday with no references to Australia, has sparked outrage from climate scientists, who were not informed that their contributions had been removed.

Australia is one of the largest carbon emitters per capita because of its reliance on coal-fired power plants for electricity.

Despite pledging to cut carbon emissions, Australia has continued to support fossil fuel projects, including Adani Enterprises Ltd's proposed A$10 billion Carmichael coal project in the Galilee Basin in western Queensland.

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