Like me, I'd guess that none of those commenting here about the cause of this exceptional bush fire season (and in particular their relationship with global warming, if any) has any academic/professional qualifications or practical knowledge of the subject (but by all means correct me if I'm in error). Hence, although I've followed this thread and made a couple of observations, I've abstained from commenting on the causes of these terrible fires. I don't know the cause but defer to those I can reasonably expect to know far more than me or the media commentariat. Although I'm sure it's not perfect, I think a video from 'Potholer54' (see below) does a good job of pulling together what's being claimed in the media and contrasting it with what the expert scientists & firefighters have to say about the matter. Interesting viewing .....
https://www.youtube.com/watch?v=t0x46-enxsA
Thanks for that link with it's interesting contrast, though as a local I should say that those talking media heads are so far right wing that they are out there with the blinking navigation lights. Sky News is Murdoch owned - I don't have the stomach to watch or read a single thing they present. Peta Credlin is a former Chief of Staff for the 'mad monk' Tony Abbott when he was PM, before he was rolled by more moderate Liberal (Australian Liberal so right hand side of politics) Malcolm Turnbull, who was in turn rolled himself by 'God bothering' Scott Morrison as a compromise after a failed coup by far right 'walking dead undertaker' Peter Dutton. The others are even more extreme than her. Shock jocks is too tame a term.
Having said that, we should say that even mainstream, more moderate, or even left leaning 'green' media, and indeed science does not have a handle on the causes. These causes unfortunately cannot be divorced from the history, the governance, exploitation, or management of the continent.
Australia is a continent of droughts (and fire) and flooding rains.
Now though, because of the way the country has been treated, they are increasingly becoming destructive processes.
We are on the tail end of a widespread multi-year drought which is corresponding with record positive levels of the IOD. It has been a cracker in living memory. In terms of history it is a mere blip on the radar with the archaeological record revealing decade or more long droughts - droughts which Aboriginal people lived through.
A main cause is the ruined hydrology of the landscape. I have detailed that in several threads. Dryness creates heat. Suffice to say that with an intact building hydrated soil sponge that even though we are in drought, wetlands would survive, water tables would be higher, rivers would be flowing, the vegetation would be more moist, temperatures would be cooler, the transpiration cycle would be intact, and localised rain may fall. The 'modern' science on this has been virtually non-existent and is an important emerging field. If the 'climate' in Australia is changing, this (among other factors) is one of the reasons.
The NSW RFS Commissioner himself has said that more prescribed burning would not have prevented this disaster. Prescribed burning is something I am not a fan of. It fosters more fire loving and fire prone vegetation. Even if more environmentally friendly Indigenous burning practices had been practiced it would not have prevented some of what we have seen from starting - it certainly would have helped to contain it.
Again, this is an area that needs much further scientific study, and cannot be divorced from the hydrology of the land, nor indeed governance and usage. Edge effects from human population sprawl and footprint is another major problem - with all the fear and trauma of this disaster, knee-jerk calls for more back burning, more buffer would be an ecological disaster - leaving an area the size of several European countries as wastelands.
All of these areas need far more study to determine if natural cycles are changing in any way. We should address the factors (hydrology, governance, management, footprint, respect, etc) that we can, immediately.
As for the specific fire behaviour we have seen, that results from the dryness of the landscape, the heat that, and drought cycles cause, and the high winds combining with these high temperatures. This (40+°C temps and 80+km/hr winds) is not only sending Fire Index ratings off the charts, but it makes these conflagrations uncontrollable - generating their own weather systems which is sending firestorms spotting in all directions. Ember attack is a big feature of a lot of the houses lost.
As for ignition sources, it is easier to get rocking horse poop than it is to get detailed information about this from any of the Agency's or Government Departments. Man-attributable causes feature more prominently than has been let on. If dry lightning does strike during those 'catastrophic' weather conditions then one fire can naturally spawn successors.
Chosun :gh: