A chapter on Australia in the report warns that coral bleaching in the Barrier Reef is likely to become an annual occurrence by as early as 2030 due to warmer, more acidic seas.
Bleaching occurs when the plant-like organisms that make up coral die and leave behind the white limestone skeleton of the reef.
Climatologists say Australia is suffering an "accelerated climate change", putting the Barrier Reef's corals at particular risk.
The Barrier Reef, a world heritage site, stretches over more than 345,000 sq km off Australia's northeast coast and underpins a tourism industry worth an estimated $4.5 bn a year.
The Australian government, which is pushing hard for nuclear-powered electricity generation, is under pressure to take more immediate action to combat climate change.
The Barrier Reef is the world's
largest living organism [Reuters]
Commenting on the IPCC findings, Tim Flannery, an Australian scientist and climate change expert, said the report was a conservative take on rising temperatures, but could be a useful benchmark to tackle global warming.
"The actual trajectory we've seen in the arctic over the last two years if you follow that, that implies that the arctic ice cap will be gone in the next 5 to 15 years," he told Australian radio.
Flannery predicted a much worse scenario.
"It could be worse than this. There's a 10 per cent chance of truly catastrophic rises in temperatures, so we're looking there at six degrees [Celsius] or so… a disaster for all life on earth.
"We will lose somewhere between two out of every 10 and six out of every 10 species living on the planet at that level of warming.
"It will set in train a series of climate consequences that will run for a thousand years."
He also brushed off the IPCC's use of the words "very likely" in relation to climate change having a human footprint.
"I don't think that that's an issue for debate any more. It's our problem, we have to do something about it," he said.
"We have the tools, we're so far we're lacking the will."