Leading researchers are urging immediate action to save the world's coral reefs as they struggle against the combined impacts of global warming, overfishing and pollution.
While the future of coral reefs is unclear, new research has found it is not too late to save them.
"The reefs of the future will be radically different from today or 30 years ago," James Cook University professor Terry Hughes said.
"But, if we take the right steps immediately, we can - and must - secure a future for reefs, recognising that the possibility of restoring them to their former condition is no longer possible."
Prof Hughes, director of the ARC Centre of Excellence for Coral Reef Studies, led the study on reef futures and their capacity for rapid shifts.
The findings will be revealed in scientific journal Nature on Thursday.
Prof Hughes is among a group of researchers who say the window of opportunity to save the world's coral reefs is closing rapidly due to constant dredging, overharvesting, pollution, sewage, sediments and increasing temperatures.
The scientists have pegged their hopes on the Paris agreement, a carbon reduction pact within the United Nations Framework Convention on Climate Change.
Prof Hughes is emphatic about the importance of the agreement to reefs.
"They'll be different, but recognisable as coral reefs," he said. "However, if COP21 fails badly, coral reefs as we know them today will be destroyed."
US President Donald Trump this week signalled he may withdraw from the agreement, but is yet to decide amid pressure from foreign governments and within his own Republican party.
