Scientist and Australian of the Year Tim Flannery said the report from the Intergovernmental Panel on Climate Change showed previous research underestimated the danger and that the tipping point on climate change passed in 2005.
"We thought we'd be at that threshold within about a decade," Prof. Flannery told the national broadcaster ABC. "We thought we had that much time, but the new data indicates that in about mid-2005, we crossed that threshold."
Flannery said growing economies meant growing greenhouse gas emissions and that meant a growing threat of global warming.
"We've had growing economies everywhere," Flannery said. "We're still basing that economic activity on fossil fuels. You know, the metabolism of that economy is now on a collision course, clearly, with the metabolism of our planet."