When former NSW Rural Fire Service district manager Superintendent Patrick Westwood described the “freakish” weather and winds of fires he attended, he said “veteran firefighters don’t believe what they saw”.

Key points:

  • Researchers simulate some of Australia’s trickiest fires to better understand fire weather
  • The modelling could eventually run real-time to help predict deadly winds and fire tornadoes
  • Research already shows climate change and heatwaves fuel erratic fire behaviour

The winds were strong enough to fatally flip an 8-tonne fire truck, the same winds he and his team battled during the Green Valley bushfire in 2019.

So in response, scientists are now working to get ahead of deadly fire weather.

They simulate their own firestorms on a Canberra-based supercomputer, one the biggest in the Southern Hemisphere, to better understand what drives the increasingly erratic weather facing fire crews.

Bureau of Meteorology senior research scientist Dr Mika Peace and her team have picked five fires to study from the 2019-20 Black Summer event: 

These fires were put forward to Dr Peace’s team due to the complexities in suppressing and containing them.

A fire tornado lifted up a Culcairn RFS truck on December 30, 2019, and smashed it onto its roof.(Supplied: Andrew Godde)

It takes an entire day to simulate just one day of these fires with the Australian Community Climate and Earth System Simulator (ACCESS) fire model on the National Computing Infrastructure (NCI) supercomputer, but the research is paying off.

“The Black Summer fires really provided the motivation to look at these fires in more detail because some of the traditional methods of surface-based fire prediction simply weren’t working,” Dr Peace said.

“[They] weren’t giving the right results that matched the observations in Black Summer.

The National Computational Infrastructure centre in Canberra is modelling catastrophic fires. (Supplied: NCI)

Predicting a firestorm

The factors behind each fire are complex and there is no single predictive formula.

The research shows that drought and heatwave conditions experienced in the lead-up to and during all five fires were a key factor in priming the landscape for extreme fire behaviour.

But local weather conditions, including sea breezes and hot overnight conditions, were also important when combined with the very dry vegetation.

An RFS firefighter captures a photo of a fire tornado in December 2019.(Supplied: NSW Coroner’s Court)

“One of the interesting things is we looked at five different fires, and in each of those five fires the processes were different, so there’s not a one-solution-fits-all scenario in term of predicting the fire’s behaviour,” Dr Peace said.

“The fires were interacting with the atmosphere in different ways in each fire.

“Particularly [of interest is] when we are looking at things like sea breezes interacting with the fire front, winds mixing down from above the surface, and these extreme fire generated winds that happened from behind the fire front.”

Farm firefighting units played a big role on Kangaroo Island during the January 2020 bushfires.(Supplied: Sabrina Davis)

Scientists are now working to break down the results and roll out their knowledge to those on the ground.

“We have been talking with these fire agencies around the country and we are developing training material to help … look for the ingredients which are favourable in providing the right conditions for extreme fire behaviour to occur,” Dr Peace said.

Helping fire fighters in real time

Fire raged in Stanthorpe on Queensland’s Granite Belt in September 2019.(ABC News: Stephen Cavenagh)

The research started in 2010, but Black Summer pressed the need to better understanding the “freak” fire weather firefighters were reporting.

The studies will also focus on fire-generated weather seeds, such as the fire tornadoes that developed during Black Summer, and working out models to better identify where they might develop in future.

Eventually, the fire modelling could be run simultaneously with Australian fires to help firefighters get on the front foot, particularly as climate change and heatwaves are predicted to fan larger blazes in the future.

“The question at the moment is what it looks like and how much computing power we have and need to run these computing models on-demand.”

The research was a partnership between the Bushfire and Natural Hazards Cooperative Research Centre and the Bureau of Meteorology, run in collaboration with fire and land management agencies in each state.

Its Black Summer research program is investigating key issues from the 2019-20 bushfire season.