A conversation about bushfires, climate change, traditional knowledge and western science

A few years ago, a comment of mine was apparently censored by one of many academics whose opinions are freely promoted in The (one-sided) Conversation. So I no longer bother trying to engage in that medium. But a colleague sent me a link last week which was a red rag that trapped this slow-learning pheasant.

Self-styled Professor of Pyrogeography – David Bowman announced "a quantum shift in public awareness". Since the recent gigafires, we've apparently suddenly realised that Aborigines maintained a healthy, safe and biodiverse landscape by burning. Bowman's statement has little to do with public awareness. Rather, it seems to demonstrate isolation from reality by self-congratulatory academic groupthinkers in their small, sheltered world. Bill Gammage's multi-award-winning book seemingly made no impression on them. Similarly, the Southern Hemisphere's premier ecological journal Austral Ecology didn't review my book about Firestick Ecology because "most of Australia's leading fire ecologists …declined" and the book review editor found herself incapable of writing a "balanced review".

In 2003, our House of Reps Inquiry into A Nation Charred heard a consistent message from experienced land managers right across Australia. Mild burning is the key to a healthy and safe landscape, as it was for tens of thousands of years, including periods of extreme climate change. However, the 2004 COAG Inquiry employed a Fire Chief and two Academics to bury that message and inflict another two decades of pestilence and holocaust on us. Now, two dozen ex-Fire Chiefs are using Climate Alarmism to divert attention from their failures and are seeking to pervert the latest Royal Commission. I wonder how many more innocent people and animals have to die or suffer needlessly.

The Conversation article contained three key messages:

1 Controlled burns often fail to slow a bushfire.

It linked to a paper from Professor Bradstock's grandiosely monikered Centre for Environmental Risk Management of Bushfires in Wollongong. This paper purported to show that burning mostly doesn't help fire management in NSW, VIC and SA. Supposedly, it works in WA because it's biogeographically different over there.

But more than half a century of real data from WA showed that, irrespective of climate change, prescribed burning helped to reduce the number and extent of wildfires, especially megafires. Mild burning had little influence in average fire seasons and great benefits in severe fire seasons. Most importantly, at least 8% of the landscape has to be treated to make any difference. Fire experts from Universities in Wollongong, Melbourne and Hobart don't seem to have had any experience of using mild fire to maintain healthy and safe landscapes. However, this is apparently no impediment to making models which incorporate their ideology rather than empirical data. For example, when Mr. Bradstock was employed by NSW National Parks and Wildlife Service, he made a model supposedly showing that you have to burn more than 30% of the landscape each year to make a difference and that this carries a high risk of plant extinctions.

Bradstock's crew at Wollongong University supposedly tested the efficacy of burning in south-eastern Australia by comparing the area burnt each year by wildfires against the area burnt in preceding years by mild fires and wildfires. They apparently assumed incorrectly that fuel quantity and structure develop in the same way after a fire irrespective of its intensity. In fact, fuels accumulate very rapidly after high intensity fires. They didn't test or even report the areas treated in preceding years, against subsequent areas burnt by wildfires. Miniscule areas were actually treated. For example, in the Sydney Basin, the average area burnt in preceding years by both mild and wild fires never even reached the minimum level of 8% required for prescribed burning to have any effect. I'd expect that a scientist who thought that 30% was the minimum effective treatment might have noticed this problem.

It's even more perplexing that they seem to have taken the severe fire seasons out of the analysis: "The annual weather variables [maximum temperature, number of days above 35 °C, number of days with relative humidity below 15% and rainfall anomaly] were used to partition the variation in area burnt that was due to meteorological rather than past-fire causes". Interestingly, one of the new Wollongong University crew had been the leader of the WA scientists whose analysis revealed that the biggest benefits of prescribed burning occurred in severe fire seasons. I don't understand why the new research was published. There seems to be a fundamental problem in the academic peer-review system. But NSW Government was clearly impressed. They recently funded Bradstock to the tune of $4 million to do more of the same.

2 There's no evidence 'greenies' block bushfire hazard reduction …

I suppose it depends on your definition of a greenie.

Fair dinkum science indicates that health, safety and biodiversity can be maintained in eucalypt forests by mild burning every 3-6 years.