A study by a group of Australian researchers found that the Great Barrier Reef is unlikely to recover from a 2016 heat wave that killed over 200km of coral.
The world heritage site was damaged by record high sea temperatures that caused the coral to expel living algae before calcifying and turning white, a destructive process known as bleaching.
The 2016 incident was the worst ever of its kind recorded at the site.
Scientists said the future of the reef itself could be in danger and that its fate would be closely tied to the fight against climate change. They highlighted the importance of hitting the Paris agreement target for global warming, set at under 2 degrees celsius by the end of the century.