Fire authorities expect bushfire activity for much of Australia to be consistent with annual spring levels.
The spring bushfire outlook and map released at today’s annual Australasian Fire and Emergency Service Authorities Council (AFAC) conference shows some parts of the east coast could have reduced fire potential in spring, while central and north-western Australia have increased risk.
The rest of the nation maintains ‘normal’ fire potential – that means the chances of bushfire occurring within much of the country are consistent with usual expectations for this time of year.
But while the likelihood of a La Niña event bringing cooler and wetter spring conditions has been factored into the ‘lower than normal’ bushfire outlook for some parts of the east coast, the region’s status could quickly change if higher than average rainfall fails to occur.
Even with a ‘lower than normal’ risk assessment, bushfires can still break out where fuel and hazardous conditions allow, particularly if recent rainfall has led to increased vegetation loads.
Bushfire outlook says High fuel loads still present risks in eastern Australia
Although some areas of the east coast are likely to see below normal fire conditions over spring, these projections could change if expected above-average rainfall fails to eventuate.
The outlook notes that an absence of higher-than-average rainfall would restore ‘normal’ status to these regions.
“There are likely to be periods of elevated fire danger in grassland and cropping areas of NSW, particularly in the northwest and southwest,” the outlook says.
“Seasonal conditions in Victoria were favourable for the start of the 2022-23 winter cropping season and this may result in extra growth of grass and crop fuels through most areas in Spring. It may result in an increase in fire potential later in spring, as curing advances.
“Should the expected above average rainfall not be received, then we would expect to see normal fire potential for grasslands in the ACT during spring.”
Highest risk for parts of WA and NT
AFAC has given a higher-than-normal grading to parts of northern Western Australia and the southern regions of the Northern Territory (Central Australia).
WA’s bushfire season is underway in northern areas of the state, with high vegetation fuel in Dampierland, Central Kimberley, Old Victoria Plain, the Great Sandy Desert, the Pilbara and Gascoyne. Spring is also a high-risk time for regions in the NT’s northern savanna regions.
The NT is expected to experience conditions supporting increased fire risk into September, but increased rainfall in early spring may offset this.
While most of Central Australia will have a normal rating, the regions surrounding Alice Springs have a higher risk in spring including parts of the Macdonnell Ranges, Burt Plain and Finke bioregions.
Situation “normal” for most of Australia
All of Queensland, South Australia and Tasmania, as well as the majority of NSW, Victoria, Western Australia and the Northern Territory are considered to have normal fire potential for spring.
Climactic influences like a third La Niña event and a negative Indian Ocean Dipole (IOD) could push the start of fire season toward the end of spring.
But South Australians are being encouraged to “prepare their plans and properties” in case increased rainfall doesn’t eventuate through spring. It’s a similar situation for WA’s southern areas, which could see their fire season brought forward if current rainfall deficits continue.
The timing of the Tasmanian fire danger season will be determined by whether the island’s dry winter condition continue, with AFAC noting late winter rains “will be important to determine the timing for the spring burning season.”
Matthew Agius is a science writer for Cosmos Magazine.
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