Updated
Both the bushfires and the heatwave ravaging parts of Queensland have been described as extraordinary and abnormal.
Key points
- Fire ecologist Dr Philip Stewart says the intensity of Queensland's bushfires is abnormal
- Heatwave expert Dr Sarah Perkins-Kirkpatrick says the heat wave is concerning
- Bushfire and Natural Hazards CRC CEO Dr Richard Thornton says people need to recognise the changing nature of risk
Bureau of Meteorology Queensland manager Bruce Gunn said records had tumbled in a week of widespread and protracted heatwave conditions, combined with catastrophic fire danger.
"On Wednesday, Rockhampton Airport recorded catastrophic [fire] conditions for approximately three-and-a-half hours," Mr Gunn said.
"This was the first time this district has recorded catastrophic conditions and the most prolonged event in Queensland since the implementation of the current Fire Danger Rating System in 2010."
Fire ecologist Philip Stewart said Queensland's fires of the past few days were historically unusual.
"When one looks at the charcoal records with Aboriginal burning, we haven't seen any indicators that show that there had been mass fires or large intense fires like we are seeing today, or 'mega-fires', as I would call them," Dr Stewart said."They're not something one would expect at this time, but then again, fires of this nature can occur anywhere, provided that there's the right climatic conditions and the right fuels and so on."
Dr Stewart said the intensity and the extent of the fires was abnormal, as was the time of year that they were occurring.
He said they were "absolutely" a result of climate change.
"Climate is a driver of wildfire and of fire full stop," Dr Stewart said.
"So when we start to see an increase in temperature, we start see an increase in energy availability in that atmosphere, and that obviously will increase the potential for high-intensity fires and fast fires as well."
Will fires like these become more common in the future?
Dr Stewart said he did not have a crystal ball.
"It's really difficult to say yes or no. At the end of the day, if it continues like this, the indication is that, yes we can see more fires like this, absolutely.
"But there's a caveat there that if climate change is so radical that we start to see massive fires there will be a change in the dynamics of vegetation and a change in the fuels.
"It could be a change in landscape as well, so there could eventually, over time, be such intense fires that they actually cause a change and a die-out of fuels in those areas."
Dr Stewart said fire had the potential to wipe out rainforests.
"From a biological point of view … most of the species within a rainforest are what we call pyrophobic or fire intolerant.
"Eucalypt and open eucalypt forest, et cetera, are fire tolerant … whereas most rainforest species don't have anything like that at all," he said.
Don't forget about the heatwave
Heatwaves historically have a higher death toll than fires in Australia.Sarah Perkins-Kirkpatrick, future fellow at UNSW's climate change research centre, is an expert on heatwaves in Australia. She said this heatwave was quite unusual.
The humidity is especially low, the temperatures are especially high, and it is lasting much longer than a usual heatwave, she said.
The tropics were usually hot, but these conditions were dry too, Dr Perkins-Kirkpatrick said.
"Usually the humidity is quite strong at this time of year as we move into the wet season and that really hasn't occurred," she said.
The high humidity would usually counteract the higher temperatures as we move into summer, but that is not what has happened over the past week or so, according to Dr Perkins-Kirkpatrick.
She said Australia usually had short, sharp heatwaves which lasted three to four days, but this one had been going for at least a week and was forecast to last even longer.
"It may not be as intense for that whole period, but it doesn't seem to be showing any signs of ending anytime soon," she said.
Dr Perkins-Kirkpatrick said that heatwaves were becoming more frequent and longer, no matter where you looked.
She said the tropics in particular could expect a lot more heatwave days in the future than what they were used to.
Heatwaves were also expected to get warmer, she said.
"But certainly, even within those trends, this particular heatwave that's occurring now is quite concerning, as it's been a lot hotter than what we would have expected based on those trends."
The fire offseason is changing
"We have definitely seen over the past 10 to 15 years an earlier onset of burning and a later fire season as well," Dr Stewart said.He said the fire seasons were starting to overlap, within Australia and globally, so sharing resources would become harder.
And the tropics burning this week demonstrated that even areas traditionally considered safe were at risk.
"I would say that wherever you are you should have a fire plan … even [in] urban areas as we've seen in Greece recently, right down to the coast, and in the Californian fires … there's always a possibility that a fire can get in unless it's a concrete jungle," he said.
"There needs to be a paradigm shift in the way we look at fire and the way we think about fire.
"One can't expect the government to take control of all fire management," Dr Stewart said.
Another focus should be improving bushfire prevention so that fewer people needed to put their lives on the line managing fires once they had started, he said.
What have we learned?
Bushfire and Natural Hazards Cooperative Research Centre (CRC) CEO Richard Thornton said past fires were not necessarily predictive of future bushfires, so people needed to consider the worst-case scenario for them.
"It's about forward planning and getting people to recognise the changing nature of risk," Dr Thornton said.
"I think what we can say more generally and this doesn't apply just to Queensland … is in the Australian context, if we have days that are in the 40s with very high winds and very low humidity, the chances of fire starting and becoming uncontrollable very quickly, is highly likely.
"On those days, communities need to be very vigilant and aware of the environment and what their plans are for those days, and whether it's going to be to leave early," he said.
Dr Stewart said he would like to see an increase in funding for fire management and crews.
"There's an absolute dire need for an increase in funding for fire research, which is really not there."There is very little funding available for any proactive fire management and fire mitigation research.
"We need a lot more, especially in Queensland," Dr Stewart said.
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