Back to basics approach to bushfire behaviour in Australian vegetation

Red Eagle has produced a series of papers about aspects of severe bushfire behaviour in Australian vegetation. Hopefully, the Papers are easy to read and assimilate. The aim is to show you that even a Black Saturday inferno is explainable and can be prevented when you know the causes and pre-requisites of flame and spotting behaviour.

The first paper is a manual of bushfire behaviour mechanisms. Before you can discuss bushfire behaviour meaningfully, you should be able to describe its spread mechanism and its flame height mechanism. This paper should help.

1             MANUAL of Bushfire Behaviour MECHANISMS in Australian Vegetation

2              Spot fire direction and spread in severe bushfire attack in Australian vegetation on Black Saturday   We need to understand that the East Kilmore fires were thousands of leap frogging spot fires running independently with the wind

3              Flame spread and flame height in eucalypt forests and grassland in severe bushfire attack on Black Saturday    We need to understand how broken terrain prevents development of head fires, but launches ember attacks from ridgetops that generate leap frogging spot fires downwind. When we know the mechanisms, we can plan mitigations and defence.

4              How the East Kilmore Black Saturday fire got away    In the worst-ever bushfire weather, this fire spread barely 6m in the first two hours. Why so slow? Why did the fire fighters not stop it? Read this account from the mouths of the fire fighters. It removes any doubt that the fire agencies’ Plan A protection model, ie, suppression by fire fighters and aircraft, has very limited capability to deal with running bushfires, and makes very clear they have no Plan B, ie, to protect the threatened towns. It is now almost 10 years since Black Saturday, and there is still no Plan B. They still apply their Plan A to “protect” us, the fires still escape and run as unhindered infernos towards unprotected towns and settlements and still wipes them out. We have included Paper 10 below to show people how a Plan B solution can work to save our houses from the inevitable (but unacknowledged by the fire agencies) Plan A failures. 

5              Back to basics approach for bushfire behaviour research – Project Vesta needs reanalysis   Project Vesta collected some excellent findings about fire behaviour in eucalypt forest with shrub understorey, but fails dismally in its analysis. It lumped all the data together, rather than separate them according to correct spread mechanism (see paper 1). As a result, they generated the rate of spread model for a head fire with impossible speeds. Will they listen to constructive criticism? A subsequent paper by the Vesta researchers recommended the McArthur Meter fire behaviour tables be binned. I say NO. If we remove its fuel load algorithm and use his findings for 10 t/ha, the figures for a head fire flame under the forest canopy are use for planning purposes. For spread rate by ember generated fires, a new model is required, as suggested in Paper 8. 

6              Usable findings in major bushfire behaviour research in eucalypt forests – McArthur, Burrows, Vesta    There have now been four major studies in fire behaviour in eucalypt forests. They have found different things. We now analyse their worth against the bushfire mechanisms in Paper 1

7              Effect of Fuel Moisture Content on flammability of forest fuels    This paper examines the large FMC’s used by the researchers in Paper 5 and 6 for eucalypt litter and examines their purpose and consequences. The practice was initiated by McArthur for a specific purpose and was not overturned by later acolytes. It is a very sad departure from grass roots scientific principles.

8              Predicting spread rate of leap frog spot fires in severe bushfire weather     The major Black Saturday fires spread by leap frog spot fires, thousands of them all running independently in tandem with the wind. This paper uses figures from documented spot fire-led fires and explores a theoretical method of estimating rate of spread of the leading spot fires, eg, up to 15 kph and more.

9           Self Defence Against Bushfire – A Systematic Approach        This paper shows how bushfire behaviour knowledge is invaluable in bushfire-protecting the house, the settlement, the town. It keeps the running inferno flame low and at a distance, thereby creating a safe workplace for firefighters and residents to self-defend houses.  It has a valid scientific basis. The paper shows how appropriate infrastructure has existed in many bushfire-attacked towns, but being unrecognised by the fire agencies, they made the wrong decisions and houses were lost.   

 

Back to basics? Why?

Red Eagle is increasingly concerned that researchers and fire and emergency authorities are diverging further each year from core scientific standards and principles in bushfire behaviour and threat management. Such divergence is preventing theoretical and practical advances in these disciplines.

– Bushfire researchers in their quest for the perfect fire spread model cut scientific corners, extrapolate good and bad research beyond its design criteria, verify models without understanding the concept of bushfire behaviour mechanisms.

– Authorities apply policy and laws based on bad research, misquoting or selective quoting of good and bad research, applying limited equations beyond design criteria. They impose their ill informed will on trusting citizens in legislation and reinforce it by clever and expensive media campaigns.

The outcome is a decline in living standards and the cash reserves of its burnt out citizens. Taxes and insurance premiums rise because bushfires destroy tens or hundreds of houses in unprotected towns in an afternoon, and new home builders have to pay tens of thousands of extra dollars on fire resistance design that does not even work in a placid bushfire.