Communities and firefighters could soon receive real-time warnings of risks from bushfires down to a matter of kilometres, according to a new model being tested this fire season.
As fire crews across south-east Australia prepare for an unusually active bushfire season amid an abnormally warm spring and an intensifying El Nino, researchers hope technological advances will soon give communities real-time information on the probability of fire threats down to a resolution of a few kilometres.
"People want to know: It's a fire danger, but a fire danger to what?" says Ross Bradstock, director of the Centre for Environmental Risk Management of Bushfires at the University of Wollongong, and one of the developers of the new model.
"It incorporates the probability of a fire starting and spreading, based on the fuel and the terrain, and it reaching property," Professor Bradstock said. "The warning system can be tailored to parts of towns or even suburbs."
The current warning system, modified after the 2009 Black Saturday bushfires in Victoria to include a "catastrophic" threat level, has been based on the McArthur Forest Fire Danger Index first developed in the 1960s. That method, however, is based only on weather, such as temperature, relative humidity and wind speed.
The variables included in the National Fire Danger Rating System Probabilistic Framework range from fuel load and its type, the nature of the terrain and the housing density in a particular region.
A prototype was tested in the Sydney region including the Blue Mountains and an area east of Melbourne stretching from the Dandenong Ranges to Phillip Island. The model will be tested by fire authorities in NSW this fire season, with the findings to date published by the Bushfire and Natural Hazards Cooperative Research Centre.
"You can have a region with a lower fire rating but have a particular location with a higher risk," Trent Penman, a bushfire behaviour specialist at the University of Melbourne, and another developer of the new model. "For people in those properties to know they are at higher risk would be beneficial for their preparations."
Victoria and NSW are divided into large fire districts, and the new model potentially could provide "fine grained" warnings of potential property loss down to five kilometres or less.
Richard Thornton, chief executive of the Bushfire and Natural Hazards CRC, said the existing fire danger rating system had been largely unchanged since the 1960s.
"A new fire danger rating system is a national priority and it is crucial that it is underpinned by the best science available," Dr Thornton said.
"This is about improving public safety and using science to more accurately predict and communicate bushfire risk," he said. The work is being coordinated by the federal Attorney-General's Department and involves state and territory emergency services, the Bureau of Meteorology, CSIRO, and several universities.
Kevin Tolhurst, an associate professor in fire ecology at the University of Melbourne, said the probabilistic model was one of several being considered by fire authorities.
The new system could take "two or three years before it is routine", and a key issue will be how the information is communicated to the public, particularly if warnings become much more detailed.
While avoiding confusion will be a challenge, the more specific warning may also result in greater involvement from residents.
"With fire management, you want individuals to respond to what is a community problem," Professor Tolhurst said.