Devastating bushfires that swept Australia in recent months were at least 30 per cent more likely as a result of climate change, scientists said on Wednesday, warning such fires may create unmanageable risks as emissions and temperatures rise further.

An eight-week study into how heat and drought contributed to the fires found that hotter-than-normal conditions in Australia, in particular, showed a strong link to climate change.

It also suggested scientific models may be vastly underestimating coming impacts from rising heat.

As climate-heating emissions continue to increase, "we will be facing these extreme conditions more often than in the past," said Maarten van Aalst, a climate scientist and director of the Red Cross Red Crescent Climate Centre.

Should we be worried about this? Yes, very. - Maarten van Aalst, director, Red Cross Red Crescent Climate Centre

"Should we be worried about this? Yes, very," he told journalists.

He and other researchers from Australia, Europe and the United States carried out the analysis under the World Weather Attribution project, which provides rapid scientific evidence on how much climate change is fuelling extreme weather events.

The group and other scientists have so far conducted more than 230 such studies, linking last year's record-breaking heatwave in France and extreme rainfall during Tropical Storm Imelda in Texas, for instance, to climate change.

The Passionate Eye is streaming a documentary called Australia's Black Summer Friday, March 6, on CBC Gem, and airing Saturday, March 7, 10 PM ET/PT on CBC News Network.

Not all the events analyzed show a connection to global warming. The Australia bushfires study, for instance, did not find a clear climate-change driver for the record low rainfall that also contributed to the recent fires.

But the researchers said devastating fire seasons will be at least four times more common in Australia than they were in 1900 if global average temperatures rise two degrees Celsius above pre-industrial times.

Current heat models 'clearly underestimate the trend'

Temperatures have already heated up by a little over 1 C, and the world is on track for at least 3 C of warming, even if all countries meet their commitments to cut emissions under the 2015 Paris Agreement on climate change.

Scientists said current heat models for Australia "clearly underestimate the trend" for more devastating bushfires as climate change strengthens.

Wildlife Information, Rescue and Education Services (WIRES) volunteer and carer Tracy Burgess holds a severely burnt brushtail possum rescued from fires near Australia’s Blue Mountains, December 29, 2019. The fires are estimated to have killed 1.5 billion animals. (Jill Gralow/Reuters)

The country's unprecedented summer fires, only fully contained this month, burned 19 million hectares and claimed 34 human lives and about 1.5 billion animals, said Sophie Lewis, a climate scientist at the University of New South Wales in Canberra.

"This was an event that had an enormous ecological and human cost…. It's so important to understand this," said Lewis, who said her own family had to cancel their summer beach holiday and spend months inside their home to avoid smoke and heat.

Van Aalst said the fires showed that even a country well-prepared for disasters, like Australia, may face difficulties in coping with climate extremes and related consequences.

Some volunteer firefighters worked up to 100 days straight fighting the blazes, he noted, which suggests "at some points you're reaching the limits of what those systems can do."

Efforts to prepare for and adapt to worsening fires — from early warning systems to more robust building codes — could help, but ultimately keeping risks manageable will require slashing global emissions, he and other scientists said.