Across the Tasman, where bushfires have been a feature of the landscape for 65 million years, the incidence and cost of catastrophic fires are projected to increase as a result of climate change.
Victoria, where 450 people have died in bushfires since the start of the 20th century, is “on the front-line of increasing risk”, researchers say. Melbourne’s rural-urban fringe is described as “the most vulnerable in the world to bushfires”.
Richard Thornton, chief executive of the Melbourne-based Bushfire and Natural Hazards Co-operative Research Centre, says the frequency of severe fires such as Black Saturday (2009), when 173 people died, will increase. In some areas, the number of extreme-fire-risk days in a year is expected to double by 2050.
The approach to minimising life risk from bushfires has changed.
“We know from research that the best indicator of a house not burning down in a bushfire is the presence of people. Usually, a fire will start as a small ember-driven spot fire, and if someone is there, they can get to those embers before it burns the house down. That’s the basis of the whole ‘prepare, stay and defend, or leave early’ strategy.”
But during Black Saturday, many people died in their houses, causing a re-evaluation of the approach.
Thornton says the message now is that on very bad fire-risk days, it’s best to leave. “Life is the No 1 priority and, in order to protect your life, you should leave early and not be near the fire. That means we will probably lose more houses on those days, but the number of people who will die is less. It’s a trade-off between life saving and property saving. So you should have a trigger at which point you leave; you should not leave it late.
“Particularly on catastrophic fire-danger days like we recently had in New South Wales, the message is, ‘Do not be there,’ because we know that fires can start any time and you may not get a warning.”
Staying to defend property remains an option, but people have to be well prepared. “If you choose to stay and defend, make sure you understand the risks, that you are prepared for it physically and you are prepared emotionally for it … including making sure you have a water supply, and when power goes out, that you have a dependable pump, that you have done simple things such as mow the lawns and clear the gutters to get rid of dry leaves.
“Because the last thing the agencies want is people evacuating at the last minute. Prior to Black Saturday, we had a lot of places where people were evacuating at the last minute, getting caught on the roads with visibility virtually zero. And the likelihood of being caught in an accident by the fire is high.”