GLOBAL – The leafy suburbs of some of the wealthiest places in the world are facing a growing risk of being consumed by a devastating wildfire, according to a major new study that mapped 23 million different fires over the last decade.
The fire weather season has increased by an average of nearly a fifth over the last 30 years, a trend that is expected to continue for several decades at least because some further global warming is bound to happen regardless of efforts to prevent it.
The researchers warned their analysis suggested there could be another 35 per cent increase in the number of days of high fire danger by the middle of the century.
The south-west United States, Mexico, Brazils Atlantic coast, the European countries on the Mediterranean Sea, southern Africa and the east coast of Australia are among the places most at risk, according to a paper in the journal Nature Ecology & Evolution.
And cities with low-density housing, with lots of trees and other flammable foliage, were particularly vulnerable.
“Our global database of extreme wildfires shows that those reported as being economically or socially disastrous are concentrated in suburban areas intermixed with flammable forest in the developed world,” the paper said.
Professor David Bowman, of Tasmania University, who led the study, said extreme fire events were a global and natural phenomenon.
The research found that extremely intense fires are associated with anomalous weather such as droughts, winds, or in desert regions, following particularly wet seasons, he said.
A wet year allows vegetation to grow quickly, but a period of dry weather can then turn this into tinder-dry fuel just waiting for a spark.
The researchers focussed on the 478 most extreme wildfires out of the total of 23 million worldwide between 2002 and 2013. Of these, 144 were described as economically and socially disastrous.
Cities have been built in some of these environments. They are living in harms way and thats actually what happened in Hobart in 1967, Professor Bowman said.
It was like the people who built the city had no idea that nature could throw that sort of fire at you.
In the Hobart fire, 62 people died, 900 were injured and more than 7,000 lost their homes.
Professor Bowman said it was time to start fire-proofing cities in vulnerable areas, much like the work done to prevent significant damage from earthquakes.
He said the Mediterranean had seen fewer wildfires than other parts of the world with a similar climate because people there had managed vegetation in a way that minimised the risk.
But he said people had been increasingly leaving the countryside and moving into cities, which were sprawling into this landscape.
Weve got to understand that just plonking a cities in front of a highly flammable vegetation type is a recipe for disaster,” Professor Bowman said.
The concern is that with climate change we are going to see more of these fires.
In other words we are seeing a bad problem, that we are not getting to a grip of, about to get much worse.