Australia has entered what the Climate Council has dubbed the 'critical decade' for tackling climate change.
Now the Council has released a new report warning the climate is changing faster than expected and clearly posing significant risks for health, property and infrastructure.
The report, "Growing Risks, Critical Choices," comes in the lead-up to the United Nations climate-change conference in Paris in November and December this year.
Earlier this month, the Federal Government announced it plans to reduce emissions by 26 to 28 per cent of 2005 levels by 2030.
But the latest report by Australia's Climate Council says the climate is changing more rapidly and with more serious risks than previously anticipated.
And it says the findings justify more urgent action.
Chief Councillor Tim Flannery says the report shows the threat of climate change is continuing to grow in ways previously not clear.
"What we're seeing is that some extreme weather events whose origins were uncertain previously are now able to be strongly tied to the greenhouse gases in the atmosphere and to climate change. These are things like fire risk, wildfire risk, heatwaves -- the extent, duration and intensity of heatwaves -- and other extreme weather events like that."
Professor David Karoly, at the University of Melbourne's School of Earth Sciences, says the findings are not surprising.
"There has been plenty of information that changes in the climate system are occurring rapidly -- in fact, often -- more rapidly than had been projected in the past, that there are a wide range of substantial impacts from that and that we need to take action immediately if we're to slow down the adverse impacts of climate change on human societies."
The report highlights the fact the number of hot days in Australia has doubled in the past 50 years, with heatwaves becoming hotter, longer-lasting and more frequent.
Professor Flannery says the research points to human activity as the main cause of the changing climate.
"The key driver is the burning of fossil fuels, which is creating greenhouse gases on a stupendous scale. Last year, 40 billion tonnes of greenhouse gases were released into the atmosphere. That's an unimaginably large number. To take back 4 billion tonnes out of the atmosphere, you'd need to plant an area the size of Australia with trees, and they, of course, store CO2 out of the atmosphere, so that would get you four billion tonnes out. So, 40 billion tonnes is a lot."
The report says climate change is increasing the frequency and severity of extreme weather events like heatwaves and bushfires.
Professor Flannery says it adds to growing research in that area.
"The link is scientifically very strong, and it's also just common sense. We see that what is happening with our climate is that conditions are getting hotter, heatwaves are becoming more intense, much of south-eastern Australia is becoming dryer, and all of those factors just naturally feed into bushfire risk. So, if you get long droughts where the soils dry out and the temperatures are hotter, you get a much greater chance of runaway bushfires."
Professor Karoly says, besides increasing bushfire risk, climate change will threaten different natural environments in Australia.
"We're seeing major impacts on many natural ecosystems. So, adverse impacts on alpine areas as the temperatures warm up, meaning less snow cover, and that's leading to major loss of alpine ecosystems, but also some of the iconic ecosystems, particularly like the coral reefs in both north-eastern Australia and western Australia. And in particular, the Great Barrier Reef is at severe risk, both from hotter temperatures as well as from the higher concentrations of carbon dioxide in the oceans, leading to acidification. And there are major risks of extreme damage associated with increased frequency of coral bleaching on the Great Barrier Reef."
In November and December this year, world leaders will gather in Paris to reach a new international agreement for fighting climate change.
The aim is to keep global warming below two degrees Celsius.
The Federal Government will take Australia's proposed emissions-reduction target to the conference.
But the council's report says Australia is lagging behind global action against climate change.
Professor Karoly says the Paris meeting is a critical meeting, and he is urging the Government to take further action.
"Unfortunately, the current action proposed by the Australian Government is not going to bring Australian emissions down quickly enough. Australia will continue, even after the proposed emissions, to have the highest per capita emissions of any developed country in the world."