Heatwaves are becoming hotter, lasting longer and occurring more often, the Climate Council's latest report card on climate change says.

The Cranking Up The Intensity: Climate Change and Extreme Weather Events report has found 2016 was the hottest year on record globally.

Climate scientist Professor Will Steffen warned extreme weather events were projected to worsen across Australia as the climate warmed further.

He said the extreme heat had to be "taken really seriously, first and foremost".

"It is a risk for human health, particularly for the most vulnerable — the elderly, very young people, and exposed outdoor workers," he said.

"It is obviously a risk for the agricultural industry, it is a risk for natural ecosystems.

"We saw an underwater heatwave about a year ago wipe out a large part of the Great Barrier Reef.

"A lot of these impacts we are seeing occurring now are occurring earlier than we had projected a few years ago.

"It is giving us some cause for concern that the climate system may be shifting a bit faster than we originally thought."

Impact varies for each state

The report found the impact of extreme weather events in all states was likely to become much worse unless global greenhouse gas emissions were reduced rapidly and deeply.

In Brisbane, heatwaves are starting eight days earlier than in previous years.

The number of hot days above 35C per year is expected to increase from 12 per cent to 18 per cent by 2030.

The report also warns of increased coastal flooding. ( Supplied: Climate Council )

Maximum one-day rainfall is forecast to rise by up to 18 per cent by the end of the century.

Severe thunderstorms are expected to rise by 14 per cent for Brisbane by the end of the century.

Professor Steffen said tropical cyclones were also likely to increase in intensity, although there would not be more of them.

"They may even travel further southwards," he said.

"There will be an increase in coastal flooding as well as sea levels.

"There is a projected net warming of sea surface temperature off the Australian coastline of 2 [degrees Celsius] to 4 [degrees Celsius] by 2090.

"In south-east Queensland over the next decade or two there is an increasing bushfire risk where there are forested areas."

Most vulnerable Australians at risk

Climate Council Professor Hilary Bambrick, an epidemiologist and an expert on the health impacts of climate change, said more extreme weather events would put Australia's most vulnerable at risk.

"While we can make our health services more resilient to coping with extreme weather events, an ounce of prevention is worth a pound of a cure," she said.

"Ultimately to protect Australians from worsening extreme weather events, and to do our fair share in the global effort to tackle climate change, we have to cut our emissions quickly and deeply.

"Australia's pollution is continuing to rise while global emissions flat line."

Australian Government not doing enough: expert

The Climate Council is calling for the orderly closure of Australia's ageing coal-fired power stations to make way for modern, clean and efficient renewables.

It argued the Australian Government was not doing enough to reduce greenhouse gas emissions.

"Not even close," Professor Steffen said.

"To reach the Paris target which we signed up too, we would need to have a target in 2030 of 40 per cent to 60 per cent emission reduction on 2005 levels.

"We've only got 26 per cent to 28 per cent — it is far, far short of what is actually needed according to the science. On present projections we are not even likely to meet that weak target that we have."