WIMMERA people got a first-hand look at the latest fire research at a forum at Laharum.
Subscribe now for unlimited access.
$0/
(min cost $0)
or signup to continue reading
University of NSW School of Physical, Environmental and Mathematical Sciences lecturer Jason Sharples and ACT Emergency Services Agency researcher Rick McRae gave people an insight into fire behaviour modelling and on-ground operations at the forum on Thursday.
Laharum Fire Brigade member Bill Gardner said the session aimed to help people better prepare for fires.
He said Dr Sharples spoke about models used to predict how quickly and in what direction a fire would spread, and the increased frequency of extreme fires whose behaviour did not follow forecasting models.
“Two categories of forecast failure exist. The first is incorrect input data to existing models, and the second is that large fires are dynamic and depart from the steady state assumptions that underpin existing models,” he said.
“Incorrect data input has been shown to occur when weather conditions at the fire scene differ markedly from the nearest weather station.
“This can occur where a mountain range causes upper-level air to drop down on to land downwind.
“The land to the east of the Grampians would be a monty for this effect in a westerly wind. The ferocity of the 2015 Moyston fire came to mind.”
Mr McRae spoke about operations on the fire ground.
Data he compiled revealed extreme fires were increasing in frequency. It showed there were no extreme events between 1978 and 2000, but 19 from 2001 to 2010.
Mr Gardner said fire storms did not advance as fronts, but rather as multiple spot fires over a large area, coupled with strong and unpredictable winds.
“Halting the fire is impossible, and any co-ordinated response is probably out of the question. Asset protect is the focus,” he said.
“Typically a ‘blow-up event’ will last from half an hour to four hours, and then the fire will de-escalate to a more linear type that can the be attacked.
“It was clear from the presentation that future focus in these situations must be predicting where and when they de-escalate and can be attacked again.”
Mr Gardner said Dr Sharples’ work suggested blow-up events could be predicted from the interaction of the landscape and weather conditions.