GOVERNMENT adviser Ross Garnaut has criticised media treatment of climate change, suggesting it has undermined support for action by giving equal weight to mainstream peer-reviewed science and sceptical views not backed by published evidence.
The latest update to Professor Garnaut's 2008 climate change review, launched in Hobart last night, finds that the world is continuing to warm. He also found that the evidence that human greenhouse gas emissions are the primary cause has strengthened beyond the high level of certainty of three years ago.
Despite this, public confidence in climate science seemed to have weakened in Australia, in part due to media coverage of the issue.
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"If you take our mainstream media, it will often seek to provide some balance between people who base their views on the mainstream science and people who don't," he said.
"That's a very strange sort of balance. It's a balance of words, and not a balance of scientific authority."
Professor Garnaut said the decline in public acceptance of climate science came amid increasing suggestions in scientific literature that large damage could start at a lower level of warming than the threshold of 2degrees above pre-industrial levels recognised by the United Nations. Australia has warmed by 0.9 degrees since 1910.
The latest Garnaut update — the fifth of eight to be published before the end of March — finds that not only is the globe warming, but that most physical and biological systems are changing at least as quickly as predicted.
The pace at which sea levels are rising has accelerated. While the likely increase this century remains uncertain, Professor Garnaut said credible estimates ranged up to 1.9 metres. The climate change department estimates up to 247,600 existing homes worth up to $63 billion are at risk of inundation from a sea level rise of 1.1 metres.
"It is an awful reality that no major developments in the science hold out realistic hope that the judgments of the 2008 review erred in the direction of overestimating the risks," Professor Garnaut said.
He said he feared scientific projections to date might have been overly conservative.