Australian fire services will need to double their numbers of boots on the ground by 2030 to cope with the increased bushfire risk caused by climate change, a new report says.

Be Prepared: The Changing Climate and Australia's Bushfire Threat is the first report from the privately funded Climate Council, born out of the axed Climate Commission.

At the report's launch in Sydney on Monday, co-author Professor Lesley Hughes warned the "context" of fire in Australia was changing.

"We've had since the 1960s ... a doubling in the number of extreme hot days," she said. "And when we get extreme hot days the risk of bushfires is greater."

Australia's south-east and south-west were experiencing "a long-term pattern of drying", putting large populations living near bushland at particular risk, she said.

According to the report, Australia has experienced its hottest 12 months on record and the fire season will continue to extend into October and March in coming years.

The report says by 2030 the number of professional firefighters should double the 2010 numbers, to keep pace with the growing population and bushfire risk.

The Fire Brigade Employees' Union NSW secretary, Jim Casey, said the prime minister had to better resource firefighters and act on climate change.

Tony Abbott had been prepared to "drape himself in the flag of firefighters" during the Blue Mountains bushfires in October, he said, but wasn't prepared to act on the root cause of the blaze.

Another report co-author, Professor Will Steffen, said in the short term governments had to ensure fire services were adequately resourced to fight an increased number of blazes.

In the long term, he said, Australia needed to stop using fossil fuels and develop renewable energies to reduce carbon emissions.

Christine Finlay, who has a PhD in bushfire research, said the "incredible surge of catastrophic fire activity" was due to policies that made it difficult to do preventative burns.

"You have to hire an environment impact assessment consultant ... to make sure there's no threatened or endangered species," she said.

She said the Climate Council was irresponsible for making links between climate change and bushfires.

"If they were selling a product they would be done by the department of fair trading," she said.