This summer two of these weather systems have fanned flames on the east coast, and another one may form by the end of the week.
NSW and Victoria’s rural fire chiefs both said this week that more hazard reduction burns offered false hope on removing fire risk.
Victoria’s Country Fire Association chief officer, Steve Warrington, said: “The emotive argument is not supported that fuel reduction burning will fix all our problems”. NSW’s Rural Fire Service Commissioner, Shane Fitzsimmons, warned the technique was “not the panacea”.
Professor Bradstock said hazard reduction burning, typically carried out by state land managers and fire services in favourable weather over winter or spring, is an effective tool that reduces the volume of combustible fuel in a forest.
But to generate a significant reduction in bushfire risk would require hazard reduction burning on an immense scale in risky areas near towns, which could be cost prohibitive.
Professor Bradstock has estimated that due to increasing weather risks funding for hazard reduction burns would need to increase fivefold just to hold the threat to lives and property at current levels.
That means NSW alone would have to spend $500 million a year to maintain the status quo, and even more to reduce the risk of repeating the death and destruction of this summer’s fires.
“Hazard reduction burns carried out close to properties, within a couple of kilometres, can be very effective under extreme fire conditions up to four years or so after the bush was burnt,” Professor Bradstock said.
“But under catastrophic conditions like we’ve seen that window of effectiveness goes down to a year.”
These prescribed burns can limit the intensity of a fire, and enable firefighters to deploy suppression techniques like aerial water bombing. In areas adjacent to houses, hazard reduction can reduce the size and spread of ember attack.
A study led by the Australian National University into the Black Saturday bushfires in Victoria found hazard reduction burning within 500 metres of houses resulted in 15 per cent fewer house losses compared with hazard burns eight kilometres from houses.
“Hazard reduction near houses can be over 10 times more expensive than burning in a remote area of bush, but I’d argue it’s more cost effective,” Professor Bradstock said.
Mike is the climate and energy correspondent for The Age and The Sydney Morning Herald.