CANBERRA - Australia will suffer more frequent and extreme climate events, often happening simultaneously, which will strain industry, services and infrastructure, a government report said on Monday, ahead of the announcement of a new emissions target.

Among the conclusions of the most comprehensive assessment of risks to Australia posed by climate change were that heatwaves become more frequent and deadly, while rising sea levels will put millions at risk and plants and animals will have to move, adapt or die.

Northern parts of the country, remote communities and outer suburbs of major cities will be particularly susceptible, Climate and Energy Minister Chris Bowen said in a statement.

"No Australian community will be immune from climate risks that will be cascading, compounding and concurrent," he said.

"Australians are already living with the consequences of climate change today, but it's clear every degree of warming we prevent now will help future generations avoid the worst impacts in years to come."

Australia aims to cut carbon emissions by 43% by 2030 and reach net-zero emissions by 2050. Bowen said the government would soon announce an "ambitious and achievable" emissions reduction target for 2035.

The previous right-of-centre government was considered by clean energy advocates a global laggard for its emissions policies. Renewable energy projects have faced backlash from communities and conservative politicians and media.

Monday's report said Australia was already 1.2 degrees Celsius warmer than historical levels. It said a 3-degree warming would raise the number of extreme heatwave days to 18 a year from four now and the duration of marine heatwaves to nearly 200 days from 18 now.

The number of deaths from heatwaves in Sydney could increase by 444% in that scenario, it said, while some forests and marine life may perish.

Three degrees of warming would raise sea levels by another 54 centimetres by 2090, allowing saltwater ingress to impact fresh water supply and putting more than 3 million people in coastal communities at high risk of flooding that could occur on more than 200 days each year, up from 15 days a year now.

Health and emergency services would face pressure, rebuilding costs would rise, property values would fall and hotter, drier weather would damage crop yields and stress livestock, the report said.

The government also on Monday released a national adaptation plan that Bowen said would guide Australia's response to the report's findings.