Australians should “expect the unexpected” this bushfire season amid dangerous conditions, experts have warned, after a severe start that saw a firefighter killed and homes destroyed in several states.
Bushfires at Koolewong and Bulahdelah in New South Wales destroyed 20 homes and a natural disaster has been declared in several local government areas, while wind-driven fires at Dolphin Sands in eastern Tasmania razed 19 houses and damaged dozens more.
While battling the Bulahdelah blaze, a veteran firefighter suffered cardiac arrest after being struck by a tree on Sunday night and died at the scene, with the NSW premier, Chris Minns, describing it as a “foreboding beginning” to the season.
The extreme start follows several years that have been marked by wetter-than-average weather for much of the country and catastrophic floods in some areas.
Last month, the Bureau of Meteorology declared a La Niña was under way but the wetter and cooler weather typically associated with that climate phenomenon might not happen this time around due to factors including global heating.
The start of December has already produced heatwaves in several states. This follows a dry spring for large parts of south-eastern Australia thanks to the influence of a rare warming phenomenon – called sudden stratospheric warming – over Antarctica.
David Bowman, a professor of pyrogeography and fire science at the University of Tasmania, said “the No 1 message is: expect the unexpected”.
In a world of increasing climate instability, he said people should “stop assuming a seasonal forecast or the authorities can have some crystal ball to tell you what February is going to be like”.
Instead, he said the “smartest thing” people could do was prepare: have a bushfire survival plan and build situational awareness, at home or when travelling.
The seasonal outlook
This year, long-term rainfall deficiencies in parts of Victoria and increased fuel loads in parts of NSW and Western Australia are creating increased fire risk in southern Victoria, central western NSW and the Yalgoo and Geraldton Sandplains regions of WA, according to the seasonal fire outlook from the national council for fire and emergency services in Australia and New Zealand.
Soil moisture deficits are also driving increased bushfire risk in northern parts of the Swan coastal plain, Jarrah forest, Esperance plains and Mallee regions of WA.
Andrew Gissing, the chief executive of National Hazards Research Australia, said the outlook was designed to show areas considered at increased risk. He said this did not mean areas outside the red zones were not at risk.
“Moving into summer is certainly a call for all Australians living in bushfire-prone areas in southern Australia to be prepared,” he said.
Gissing said while fire seasons in southern Australia had been more “subdued” after rain and flooding in recent years, the indicators were starting to shift.
“Particularly with how dry the soils are starting to get. We’re starting to see landscapes dry out, so we’ll see drier fuels ready to burn.”
Dry soils and more fuel ready to burn
Ben Millington, the deputy commissioner of the NSW Rural Fire Service, said expected rainfall in the state through spring had not occurred after the rare stratospheric warming event over Antarctica “effectively pushed that rainfall to northern parts of Australia”.
He said rainfall through winter and over the past few years had encouraged growth in fuel loads.
“And what we’re seeing at the moment with those warm temperatures and strong winds is a rapid-drying trend across NSW, particularly for central-west parts of the state,” he said.
Greg Mullins, a former commissioner of Fire and Rescue NSW and a founder of Emergency Leaders for Climate Action, said the underlying factor in the often unpredictable conditions people are seeing was climate change – “because it’s making everything unstable”.
Over the weekend, Mullins joined volunteers from his Terrey Hills branch of the RFS on the Central Coast, where the group was called in to help cut fire trails through national park near the suburb of Kariong.
“It’s extremely dry,” he said.
“The Keetch-Byram drought index is how you measure soil dryness and around Gosford it’s about 160. That’s extreme dryness.”
Neither the NSW Central Coast nor the areas of Tasmania’s east coast that have burned over the past week were identified as having higher risk in the seasonal outlook, which Mullins said demonstrated that risk could occur anywhere with the right conditions.
“I’d say to people, after five wet years, put your fire hat back on,” he said.
“If you live in a bushfire-prone area, now is the time to really think about what you’re going to do to protect your family and home.”
