Fire Behaviour in Extreme Climate Conditions. K Tolhurst, April 2009
This video presentation/lecture was recorded about one month before the 2009 Victorian Bushfires Royal Commission had commenced.
The title seems inappropriate in the context of the 7 Feb 2009 firestorms only two months earlier. Clearly it was, and remains, extreme fire WEATHER conditions that are the proven problem, with repeat firestorms having barrelled across the Victorian landscape in 1851, 1939, 1969, 1977 and 1983 to name just a few.
The key take home message here, is what he already knew and said at 11min 10 sec "[...our research on the 1983 fires] showed that once you get into the extreme fire danger rating, basically THE WEATHER IS DOMINATING THE FIRE BEHAVIOUR, NOT SO MUCH THE FUEL. Fuel is really important in the low, moderate, high and very high end of the spectrum, but the fire has so much energy from the weather conditions when it gets to the extreme end, that fuel plays a lesser role. As long as there's enough fuel to carry the fire that's all we need." --- the logical sequel here is surely that for all of the forestry industry's lackeys to latch onto fuel reduction burning was almost totally irrelevant to Black Saturday's circumstance where fire danger indices were off the scale, well over 100. Fuel load has a very minor impact on fire behaviour at anything over 50 on the fire danger index: see video at 11m 20s for the description of the chart that VBRC never saw in this man's evidence.
Tolhurst in the VBRC witness stand 21 May 2009 did say that extreme fire weather, especially strong wind, was the big driver of extreme fire behaviour, BUT COMPLETELY FAILED TO EMPHASISE THE MINOR ROLE THAT FUEL AVAILABILITY PLAYED UNDER SUCH CONDITIONS. Ditto for his expert answers to Counsel Assisting questions in EXP.003.001.0007 official VBRC document. So any amount of fuel reduction burning prior to Black Saturday would have had only a minor mitigating effect on Black Saturday's extreme firestorm behaviour and its appalling death rate of 173 people. #VeryDisappointing omission that!!
This media is presumably copyright Melbourne University but its presence here is claimed as fair use, since https://slow.tv has vanished and the issue of fire prevention grows as the unstoppability of pyrocumulus firestorms worsens with anthropogenic climate change.
#fairuse #publicinterest #bushfires #wildfire #fireprevention #emergencyservices #savelives #strathewen #marysville #kinglake #lahaina #maui #hawaii #flowerdale #buxton #grantham #taggerty #clonbinane #blacksaturday #unimelb