Global warming is killing the Great Barrier Reef, study says

By Ashley Strickland, CNN

Updated 1923 GMT (0323 HKT) April 18, 2018

There are 'winners' and 'losers' among corals as they respond to the accumulating impacts of climate change.
Photos: Australia's Great Barrier Reef suffers 'extreme' coral bleaching
There are 'winners' and 'losers' among corals as they respond to the accumulating impacts of climate change.
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There are variations in the appearance of severely bleached corals. Here, the coral displays pink fluorescing tissue signalling heat stress.
Photos: Australia's Great Barrier Reef suffers 'extreme' coral bleaching
There are variations in the appearance of severely bleached corals. Here, the coral displays pink fluorescing tissue signalling heat stress.
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The different color morphs of Acropora millepora, each exhibiting a bleaching response during mass coral bleaching event.
Photos: Australia's Great Barrier Reef suffers 'extreme' coral bleaching
The different color morphs of Acropora millepora, each exhibiting a bleaching response during mass coral bleaching event.
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A bleached Acropora colony.
Photos: Australia's Great Barrier Reef suffers 'extreme' coral bleaching
A bleached Acropora colony.
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A severely bleached branching coral amongst the minimally bleached boulder coral.
Photos: Australia's Great Barrier Reef suffers 'extreme' coral bleaching
A severely bleached branching coral amongst the minimally bleached boulder coral.
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Dramatic coral bleaching, seen in Australia's Great Barrier Reef from March 2016.
Photos: Australia's Great Barrier Reef suffers 'extreme' coral bleaching
Dramatic coral bleaching, seen in Australia's Great Barrier Reef from March 2016.
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Some of the bleaching of reefs in the northern section has been described as "extreme."
Photos: Australia's Great Barrier Reef suffers 'extreme' coral bleaching
Some of the bleaching of reefs in the northern section has been described as "extreme."
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Bleaching occurs when the marine algae that live inside corals die. Of the reefs surveyed in the northern third of the Great Barrier Reef, 81% are characterized as "severely bleached."
Photos: Australia's Great Barrier Reef suffers 'extreme' coral bleaching
Bleaching occurs when the marine algae that live inside corals die. Of the reefs surveyed in the northern third of the Great Barrier Reef, 81% are characterized as "severely bleached."
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"At some reefs, the final death toll is likely to exceed 90%," Andrew Baird, of the ARC Center of Excellence for Coral Reef Studies, says.
Photos: Australia's Great Barrier Reef suffers 'extreme' coral bleaching
"At some reefs, the final death toll is likely to exceed 90%," Andrew Baird, of the ARC Center of Excellence for Coral Reef Studies, says.
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A photo taken on September 22, 2014, shows bleached coral on the Reef, a key Australian tourist attraction.
Photos: Australia's Great Barrier Reef suffers 'extreme' coral bleaching
A photo taken on September 22, 2014, shows bleached coral on the Reef, a key Australian tourist attraction.
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