I have no doubt that there are Muzzies and Greeners with Bic lighters starting many of these fires, but weeks of dry windy 110° days plays the important role. This weather may simply be an aberration, a cyclical occurrence, or an example of ongoing climate change, man made or naturally occurring. Whatever the cause, this is catastrophic.
I lived in Australia for several years.
It gets hot as blazes in the Summer there—which is right now.
They keep talking about temperatures over 40C, which is about 104 F, and really that’s not unusual at all in December and January.
The summer of 82/3 was really, really bad, with an equal number of bush fires, dust storms, a terrible drought and very high temperatures.
Also, most Australians live in the big cities/suburbs, but for those who live rurally, they really are just like American rednecks. They’ll burn trash, because there is no garbage collection beyond the black stump, and even have a fire to cook on. I’ll bet most of these arrests/charges are outdoor burning when the government said not to, and got out of hand.
I live in Alabama now, and runaway trash fires happen from time-to-time, and not everyone gets the word about a burn ban (although they should be able to figure out when the weather’s been dry!).