With a new study estimating a significant chance of an El Nino weather pattern in the Pacific, the southern Australian state of Victoria, currently enduring its worst bushfires since the disastrous Black Saturday five years ago, could face even worse fire conditions next summer,
An El Nino typically sees rainfall shift east away from Australia and is linked to dryness and active fire seasons in the country’s south-east.
There is a 76 per cent chance of an El Nino, according to a German study published in United States journal the Proceedings of the National Academy of Sciences.
‘We’re heading back into a dry period again,” Melbourne University fire ecologist Professor Kevin Tolhurst told Fairfax Media.
“In El Nino years, you have much larger and more destructive fires because there’s much more of the landscape available to burn.”
He said fire authorities should devote more resources to suppressing fires, not just in El Nino years.
That effort relies less on “our big helicopters and the massive numbers of fire trucks, which are all really important in the emergency situation”, he said.
Rather, “this is the hard slog, days after the main fire run has finished, before the next series of bad weather.”
The Bureau of Meteorology said neutral conditions for the El Nino-Southern Oscillation were likely to persist until the end of autumn at least, but warming of the Pacific was likely in coming months.
It said some models indicated temperatures in the central Pacific could approach El Nino levels by early winter.
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airfax Media reports Professor Ross Bradstock, a bushfire expert at the University of Wollongong, said the severity of Victoria’s fire season would be determined by interplay between an El Nino and conditions in the Indian Ocean.
A cooler-than-usual eastern Indian Ocean, known as a positive Indian Ocean Dipole, is also associated with a drop in rainfall in central and southern Australia.
”If you have a positive Indian Ocean Dipole event, possibly in interaction with an El Nino event, it may favour the incidence historically of major fires in Victoria,” Professor Bradstock said.
NSW, which had less than a third of its normal rain in January, would also likely have more bushfires in an El Nino year.
“El Nino effects do increase the severity of fire weather, that’s been shown historically for NSW, Professor Bradstock said.
In fact 2013, Austrralia’s hottest year on record, was also a dry one for much of the country.
Meanwhile, the Australian Bureau of Agricultural and Reource Economics and Sciences said, heatwaves and spreading drought were likely to cut the output of summer crops for 2013-14 by 25 per cent, pushing it to its lowest in four years.
Peter Collins, manager of the bureau’s agricultural commodities unit, said it was too early to say if El Nino conditions would take hold, but many farmers were already struggling with low soil moisture.
While the winter crop was a bumper one, land planted for summer crops fell 15 per cent on a year earlier.
