Bushfires, Black Saturday and the clever country


Fire has been an integral part of the Australian landscape for tens of thousands of years, and both the landscape and it’s native inhabitants have adapted to this periodic cycle of fire and regeneration. Nor are bushfires random bolts from the blue they occur regularly and predictably, yet despite this modern Australians seem to have difficulty understanding that their land  will burn, regularly and often catastrophically.

A visitor to our country might wonder why do Australians seem to studiously avoid serious consideration of the hazards of living in a country that regularly produces firestorms? Why do Australians go through the same cycle of shock, recrimination, exhortations to do better, diminishing interest and finally forgetfulness?  To put it bluntly our visitor might wonder why a nation that prides itself on being both clever and lucky appear to act with such wilful disregard when it comes to thinking about bushfire risk? Unfortunately if our visitor sat down to read the Interim Report of the 2009 Victorian Bushfires Commission to find an answer they’d be disappointed. What follows is my attempt to explain why there seems to be a fundamental disconnect between our nation’s rhetoric and it’s behaviour.

Those who do not remember the past are condemned to repeat it

George Santayana

Bounded rationality

We’d all like to believe that individually and collectively we’re rational beings, however in practice there are limits to what we know, the time we have to make decisions and our ability to hold all the facts in our heads and process them. So while we’re rational actors our rationality is limited. To deal with this problem we humans use ‘heuristics’ or rules of thumb to improve the efficiency of our our thinking.  Unfortunately these short cuts also expose us to potential biases or errors in thinking.

The affect heuristic or why we don’t fear what we love

Our visitor to Australia might firstly wonder why so many people deliberately choose to live in the bush, knowing that fires regularly reduce the landscape to ashes? The answer lies in the affect heuristic, that is humans conflate perceived benefits with their perception of risk (Finucane 2000). To put it simply we’re hard wired emotionally to  discount the risks of those things about which we have a positive emotional response. Things are either good-no risk or bad-high risk. So because we love our home amongst the gum trees, we ignore the danger that that it poses to us. As a happy coincidence this also allows us to avoid a hard discussion of the costs and benefits of ‘tree change’, lifestyles. After all if it’s good, there can’t be a down side surely?

Deciding to stay or go

Affect also governs our behaviour when dealing with stressful and dangerous situations, and in these circumstances we also rely on it to a much greater extent than we might presuppose. For example, our visitor reading through the various royal commissions might wonder why, given the evidence of how people actually behave does it seem to be an article of bureaucratic faith that people will rationally make a decision such as to stay or go, ahead of time and then stick to it in the face of such a primal emotional effect?

I am certain that events occurred very suddenly and very dramatically when the wind changed on the night in question. Daylight almost instantly turned into total blackness and burning bark and leaves showered every person and animal not undercover. People who had been hosing their homes or clearing gutters in case the fire did threaten them suddenly felt compelled to flee. Concern which had existed in the minds of many people for some time suddenly turned to extreme urgency.

Survivor, Ash Wednesday

As the quote from a survivor of the Ash Wednesday fires illustrates the extreme affect of a rapid change from a normal environment to the hellish conditions of the pre-firefront can have upon the decisions of those exposed to it. In such circumstances it’s going to be inevitable that there will be late evacuations, no matter how irrational leaving a place of shelter as the fire-front approaches may appear. Decisions are also made in a social context, here a powerful effect known as conformity bias can drive people to behave similarly to the others in a group, even if doing so goes against their own judgment. Thus the decision of a few to leave in the face of an iminent fire front can also influence even those who believe leaving late is irrational and high risk. This is we still find the charred bodies of people in burned out cars on narrow country roads.

Information does not equal enlightenment

So will information alone convince someone of the correct course of action? We also know from work on biases and heuristics in decision making that people tend to ‘cherry pick’ the information that supports their position and ignore that which does not. Therefore any public communication on fire risk is always going to be misunderstood, ignored or used in a context for which it was not intended. The more complex the message the more likely it’s failure.

Why aren’t we better prepared?

Read back through the accounts of major fire events in Australia our visitor might also be surprised to find a recurring theme of societal surprise over the the lack of preparation for what is such a predictable risk (1). Why, if we know the risk, do we do nothing? A principal method we use the evaluate the likelihood aspect of risk is the availability heuristic that is, the easier an event is is to recall the more likely the event is judged to be (Lichtenstein 1978). For rare events this leads to the absurdity bias that is when a event  has not recently occurred people will judge the event as ‘absurd’, and refuse to take actions such as insuring their property or making plans in advance. Another availability heuristic related bias is that we can also be lulled into a false sense of security by the precautions we do put in place (2). Our country fire brigades are quite effective in dealing with smaller fires thereby reducing the likelihood of loss, most of the time. People then build their houses in the bush in the belief, justified most of the time, that the local fire authority will be able to bail them out. But for extreme bushfires such as occurred on Black Saturday their local brigade cannot bail out everybody. Our visitor might reasonably conclude that Australians treat the severity of such disasters as having some upper bound magically defined by the level of severity for which they have designed their defences.

Thinking the unthinkable

Our visitor might recommend that we would be better served by ‘thinking about the unthinkable’. At an individual level this might translate to planning not just for a scenario where emergency services are functioning but also for the ‘broken back’ case, and if defending your home planning for where to go if that defence fails. For governments this might mean planning and publishing the limits of what can be done for extreme fire events such as the 2009 Victorian fire (or even worse). Even a blunt, ‘we will do what we can but you will likely be on your own’, has the value of preventing illusory expectations of help driving individual decisions before the event, as well as fear and uncertainty on the day.

I was fairly sure that we would die there, as I didn’t think we could stand up to the flames and the heat. …. Throughout the time that I was there I felt I was expecting help from some outside quarter. It wasn’t until the time that I decided to get up that I realised fully that our only help lay with ourselves…..”

Survivor of the Ash Wednesday Bushfires

So how unthinkable could it get? The likelihood of a fire versus it’s severity can be credibly modelled as a power law a particular type of heavy tailed distribution (Clauset et al. 2007). This means that extreme events in the tail of the distribution are far more likely than if we used a gaussian distribution. While a mega fire ten times the size of the Black Saturday fires is far less probable it is not completely improbable as our intuitive (gaussian) availability heuristic would indicate. In a heavy tail distribution we can apply what’s called the mean excess heuristic which essentially means that the next worse event will likely be much worse. Climate change can increase the probability of bushfires by increasing the number of extreme fire risk days, and on the day the severity of temperatures.

Note. There will still be a cutoff somewhere in terms of severity, but determining where it is with the scarcity of data in the tail is difficult, and setting severity as the the most severe event experienced to date is unwise (3).

Moral hazards and fire risk

In a market the expectation of government bailout increasing the taking of risk is termed ‘moral hazard’, the low number of properties that were insured and (Houston 2009) destroyed in the Black Saturday fire represents a version of this effect where the un-insured benefited from the local fire authority (the bailout), without having to carry the CFA levy placed on insurance (the cost).

Trying to do better next time

I’ll close this discussion as I opened with the point that the philosopher George Santayana made, if we don’t understand the past we’re doomed to repeat it. In the case of risk if we don’t understand how we made past decisions about fire risk and the biases that drove these decisions we will inevitably repeat them. I hope we can do better.

Update. NSW bushfires – Monday PM 11 November 2019 (Hunter region)

Monday evening 11 November 2019 with another worse than catastrophic fire day to come tomorrow. From where I stand we are doing no better in dealing with our increasingly fragile and hazardous landscape. Our mythical visitor from 2009 would shake his head in incredulity that so little has really changed, and how vehemently our elected leaders still deny the increasing impact of climate change upon fire in the Australian landscape. At this stage I think that the only thing that might change Australia’s attitude to fire and climate would be the destruction of a major portion of a capital city.


1.  The classical De’Moivres definition is used, i.e. the likelihood of an event times the severity of that event.

2  This effect was originally noticed in flood precautions, e.g. dams and levees reduce the likelihood of smaller floods, people then build on the flood plains guaranteeing higher losses for the rarer extreme events that overwhelm the defences (Burton 1978).

3. We should also note the fuel buildup in the landscape due to white settler land management practices and the view that any fire is bad. Likewise the rough of the major cities means far more people are exposed on the urban-bush interface. Both factors increasing the severity of fire events. Our landscape system is non-stationary in that respect. 

Further Reading

Burton, I., Kates, R. and White, G., Environment as Hazard, Oxford University Press, New York, 1978.

Clauset, A., Shalizi, C.R., Newman, M.E.J., Power Law Distributions in Empirical Data, arXiv:0706.1062v2 , 2007.

Finucane, M. L., Alhakami, A., Slovic, P., & Johnson, S. M., The affect heuristic in judgments of risks and benefits, Journal of Behavioral Decision Making, 13, 1-17, 2000.

Houston, C., Push on for forced fire insurance, The Age, 9 March 2009.

Lichtenstein, S., Slovic, P., Fischhoff, B., Layman, M. and Combs, B., Judged Frequency of Lethal Events, Journal of Experimental Psychology: Human Learning and Memory, 4(6), 551-78, 1978.

2 responses to Bushfires, Black Saturday and the clever country


    Most interested in the comparison between the BS fires and Katrina as I am in the process of reviewing “Helping Families and Communities Recover from Disaster”
    While i like your idea of getting the facts, all the information and knowledge available doesn’t help people in a crisis. In fact as you pointed out, in so many ways it is almost impossible to educate.
    one thing that does assist is to practise the protection evacuation techniques and has shown to save lives. Why fire drill home evacution is not mandatory in schools is amazing?
    There’s also the fact to live in a fire zone there are roughly three types one – it will burn (do everything to protect and leave)
    it may or may not ( do everything and stay )
    it won’t burn or if it might someone will tell us ( do what they know – no clear plan)
    I think, having sold up from a bushfire area, that a certain amount of denial makes it possible to stay.
    Watching a program on volcanoes, the children were taught in schools practiced what to do in the event of an eruption.
    Thanks for your information




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  1. Black Saturday – The Not so clever « Red presence - June 2, 2010

    […] Black Saturday – The Not so clever this gives an interesting comparison between the losses of Katrina and Black Saturday by age, plus the difficulties in preparing individuals for an extreme event Those who do not remember the past are condemned to repeat it George Santayana Fire has been an integral part of the Australian ecosystem for tens of thousands of years. Both the landscape and it's native inhabitants have adapted to this periodic cycle of fire and regeneration. Nor are these fires random bolts from the blue, they occur … Read More […]