Guest essay by Eric Worrall
Reducing available fuel seems and obvious strategy for fire risk management. But according to the CSIRO, the real culprit is climate change.
CSIRO study proves climate change driving Australia’s 800% boom in bushfires
By Mike Foley
November 26, 2021 — 9.00pmClimate change is the dominant factor causing the increased size of bushfires in Australia’s forests, according to a landmark study that found the average annual area burned had grown by 800 per cent in the past 32 years.
The peer-reviewed research by the national science agency, CSIRO — published in the prestigious science journal, Nature — reveals evidence showing changes in weather due to global warming were the driving force behind the boom in Australia’s bushfires.
Lead author and CSIRO chief climate research scientist Pep Canadell said the study established the correlation between the Forest Fire Danger Index – which measures weather-related vegetation dryness, air temperature, wind speed and humidity – and the rise in area of forest burned since the 1930s.
“It’s so tight, it’s so strong that clearly when we have these big fire events, they’re run by the climate and the weather,” Dr Canadell said.
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The weather system that drove a blast furnace’s worth of westerly wind across NSW and Victoria’s forests, sparking some of the worst fires of the Black Summer in 2019-20, will be up to four times more likely to occur under forecast levels of global warming.
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Last year, the bushfire royal commission reported fuel-load management through hazard reduction burning “may have no appreciable effect under extreme conditions” that typically cause loss of life and property.
The CSIRO findings bolster that conclusion and call into question calls for native forest logging to be used as a bushfire management tool.
“This is happening regardless of anything that we might or might not do to try to stop the fires,” Dr Canadell said.
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Read more: https://www.smh.com.au/politics/federal/csiro-study-proves-climate-change-driving-australia-s-800-percent-boom-in-bushfires-20211126-p59cgr.html
Do fuel reduction burns work?
There is significant evidence in Australia that the big problem with fuel reduction burns is they aren’t happening frequently enough.
From a fire services report written in 2015, Overview of Prescribed Burning in Australasia;
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Nevertheless, the lowered incidence and intensity of bushfires in areas that have been subject to extensive prescribed burning is compelling in south western WA and in the tropical savannah, but less so elsewhere.
Its effectiveness in temperate southern Australia appears to be most significant if undertaken at a rate which maintains at least 25% of land area with fuels younger than or equal to five years old. This condition is currently not achieved in any of the southern states.
There is also debate about the value of prescribed burning in improving the controllability of bushfires burning under extreme fire danger conditions, when weather appears to become the main driver of fire spread and extent. While the majority view amongst fire researchers is that low fuel levels have little effect on directly improving bushfire controllability under such conditions, reduced fuel levels can provide indirect benefits by freeing-up suppression forces and improving asset protection opportunities. Further, the mapping of burn severity after recent major bushfires has shown that low fuels from previous burning can significantly reduce the damage to a range of environmental values under extreme conditions, particularly in comparison to the damage incurred in forests with heavier fuel loads.
As the vast majority of bushfires burn under less than extreme conditions, it seems that most can be mitigated to some degree by lighter fuels derived from prescribed burning. However, predicting or empirically measuring this degree of mitigation is complex due to a range of factors including the variability of vegetation types and ages, the time since burning, the effectiveness of the burn in reducing fuel loads, and the weather conditions driving the bushfire.
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The strategy of trying to exclude fire from the hottest period of the year has reduced its incidence, but facilitated a situation whereby hot summer bushfires, when they inevitably do occur, can be far more damaging than they ever were – both in environmental and human terms.
This situation sees community pressure to take steps that sees the inevitable bushfire impacts both mitigated and minimised. A key element in any associated strategy is the managed use, in ecosystems where it is appropriate, of cool burning (or prescribed burning) to reduce the fuels available for unplanned summer bushfires.
Concurrently however, prescribed burning in southern Australia has become increasingly difficult to conduct on a significant scale due to a range of social and demographic factors and, over time, flammable fuels have continued to built-up as fuel loads have grown due to lengthy intervals between burns.
International bushfire historian and analyst Stephen Pyne (2006, Part Three, pp. 67 – 106) believes this has been exacerbated by Australian State governments, particularly since the 1970s, responding to perceived community concerns, centred largely but not exclusively in urban-based electorates, and excluding economic uses from many public lands. The redesignation, for example, of many areas of State forest as National Parks has left management agencies largely dependent on the ‘public purse’ to finance their management activities.
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Read more: https://knowledge.aidr.org.au/media/4893/overview-of-prescribed-burning-in-australasia.pdf
Australian forest want to burn. The seeds of many species of the dominant eucalyptus trees absolutely need fire to germinate, they have evolved to use fire to clear away the competition. Even when dry and dead, eucalyptus leaves and wood contains millions of microscopic pores filled with highly flammable Eucalyptus oil. Green eucalyptus leaves and small branches quite happily burn when ignited, thanks to the oil content. When Eucalyptus leaves and branches fall, which happens continuously thanks to ubiquitous wood boring insects, they naturally pile themselves into well aerated piles of kindling, ready to be ignited by the slightest spark.
I believe the apparent suggestion that fuel reduction burns don’t work is absurd. Eucalyptus forests always catch fire in the end, there is nothing we can do to prevent Australian woodlands from burning. If humans don’t burn off the accumulated fuel load, nature takes care of it for us, through lightning strikes or spontaneous combustion. All we can hope to do, through deliberate burnoffs, is control the timing and limit the damage.
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It was the cold sea surface waters around Australia in the spring and summer 2019 that was the culprit. No evaporation fron the sea, less clouds and less precipitation make drought and good conditions for bush fires.
The Indian Ocean Dipole ….Well spotted Kristian …
On the ABC Canadell also said beware of fuel load after La Nina. So it is/isn’t a factor on bushfire, depending on….
“”The highest area of burn actually comes right after a La Niña year, because the wetness across the continent really brings up the fuel loads,” he said.”
https://www.abc.net.au/news/2021-11-26/climate-change-increases-risk-of-megafires-csiro/100653146
https://www.nature.com/articles/s41467-021-27225-4/figures/3
And they seem to have minimised the 1974-75 bushfire season, which even if wiki is egregiously wrong, see,s to large a drop. And 1974-75 was a period of global cooling. There were 6 megafires 1990 -2020. There were 6 megafires 1960-1990.
About 3 times area burned last 30 years compared to previous 30.
I have sent an email to CSIRO for clarification.
The late 60s had mega fires all over eastern Australia…how about the mega fires 1940 to 1970? How about 1910 to 1940…..mad mega fires in the 1920s. Give us context man
Its all about the time frames picked and the ones left out….basically lies dressed up as stats
Simple solution – put these idiot mouthpieces for socialist agenda change on the fire lines for the next round of Ash Wednesday/Black Saturday fires.
After all, these ivory tower stupid people are advocating the exact same policies that CAUSED those fires to take so many lives and destroy so much property.
And people who believe this garbage from those who have never lived in the bush went out and lit fires all down the east coast more recently – contributing $100+ million to Red Cross and other charities that never passed along the gifts from Australians. (or passed along tiny amounts)
Enough of these junk-science fools!
Humidity levels are the key for the following reasons. Cooler water in the Great Australian Bight means lower evaporation volumes and rain clouds being driven northward by passing high pressure cells, fewer rain clouds mean drought, drier forest ,less moisture in the soil means less evaporative cooling and lower humidity and higher fire hazard. Farmers have known this for years. Ocean cooling, not warming causes droughts Perhaps CSIRO should not look now because its about to start again.
Lots of fires caused by Pyroterrorism. Look up on Google.
The paper is essentially saying that if you carefully choose a period that is ~50-50 split between a normal period of rain and a 1 in 100 year drought and take the end point to be the year of a catastrophic fire season (note that it has subsequently rained significantly over those areas for the next 2 seasons), you can create a graph that looks exponential.
This is hardly surprising since you would expect that each year of a 1 in 100 year drought would have an increasing likelihood of fires.
They would likely have wanted to produce a hockey stick but they couldn’t find a way of hiding prior major fires, so they took the next alternative, they truncated their main analysis to just the last 32 years.
The CSIRO no longer works for Australia.It is a lab for hire, nothing comes out unless it is paid for.
Note from the 2nd sentence quoted below, according to the CSIRO:
“When the weather conditions are extreme, our ability to manage fires becomes very limited and the effect of hazard reduction efforts decreases. But hazard reduction burning lengthens the window of opportunity for effective action when fires are controllable and increases the ability of emergency services to safely suppress a fire before it becomes uncontrollable.
Where hazard reduction burning has been carried out, we know that it slows the spread of fires, reduces their intensity, and lowers the potential for spot fires.”
https://ecos.csiro.au/hazard-reduction-burn/
Needs more emperical evidence from testing their hypotheses, more than 100 years of climate/fire history & take notice of published work instead of bias.
Australian eucalyptus forests drop litter at a high rate of 8 tonnes per hectare every year. But only 29% of this litter decomposes every year. So it doesn’t take long for the litter to build up to 15-29 tonnes/ha, a level at which, if it catches fire, is near impossible to extinguish.
So at least 10% of these forests need to be burnt every year to clear the litter. Unfortunately, Victoria and NSW only burn off less than 2% annually. Only Western Australia tries to achieve a burn-off rate of 10% every year.
The Fire Triangle, Oxygen/Fuel/Ignition-Heat, has gained another side, the Envirmentalist.
The Fire Square predicts that removal of the Envirmentalists from any potential fire situation has a double effect by also allowing the reduction of the fuel load.
Climate change is the bureaucrats ultimate get out of jail free card. Instead of having to spend time and money organising controlled burns it is far easier to throw your hands up in the air and wail “its because of climate change”
If you want bushfires in SE Australia all you need is a combination of a positive Indian Ocean Dipole and El Nino.
In El Nino years rainfall is lower in SE Australia.
With a positive IOD there is cooler water of NW Australia, lower evaporation, fewer cyclones so very little rainfall over the Pilbara. The Pilbara heats up [ferociously] and drives hot, dry NEly winds down across a dry SE Australia.
Bushfires ? You’ve got them.
Then things swap around to La Nina and you get floods across eastern Australia [like now] which will generate more forest growth, more fuel load all ready for the next positive IOD/El Nino.
“We’ll all be rooned” said Hanrahan.
The phases of the Indian Ocean Dipole (IOD) and the Pacific Ocean El Niño–Southern Oscillation (ENSO) vary independant of each other, at times like phases (wet or dry) coincide and at other times offset each other. When a IOD negative phase (wet) coincides with a Pacific La Nina phase that can be times of major flooding, but that may only happen once in 30 years or so. Likewise when a IOD positive phase (dry) coincides with a Pacific El Nino extremely dry conditions can occur across the country. Much of the time the phases may be trending around neutral or offsetting each other.
What must not be forgotten is that whatever the effects of the current phase being felt in Australia, the opposite is being felt by those areas bordering the other side of the oceans. Thus a IOD negative phase may bring wetter conditions across Australia, but leave parts of Africa facing drier conditions and so too in the Pacific. El Nino was so named because of the positive effects warmer SST bought to areas of South America around Christmas time.
Same as California: It’s not like the area has a history of forest fires for as long as people can remember. It’s not like fires are nature’s way of refreshing itself. Never let science get in the way of a good narrative.
Heck, what are they worried about? They’re all leftists now. Let it all burn down.
* Hey Mate? Didja hear about the one about the truckload of cleared firewood that was stacked next to a fireplace in the city and the brushfire area it came from burning out of control afterwards? NO? Well, neither did I! *
Climate change was the excuse that governor Newsom used in California to divert blame away from the lack of forest management by a secession of California governments. These politicians had convinced themselves that doing nothing was forest management.
Several years ago, after a particularly devastating fire season, CalFire wrote a report that made it clear that California needed active forest management. The report placed the blame on the California governmental policies which almost totally precluded active forest management. Since CalFire is responsible for fighting major fires throughout the state, their report could not be ignored. Over the past few years there have been controlled burns.
California has a long way to go after years of mismanagement. There are still 150 Million dead trees standing in California forests. California has yet to build fire breaks.
Just as a though experiment: Increase the temperature by five degrees. Then increase the wind speed by ten km/hour. Now….. try to burn that which burned last year. It won’t. Why not? No fuel. Hello? No fuel, no fire, regardless of other conditions. Not only that ridiculous example, but there’s a line, or a curve if you like, between no fuel and over abundant fuel. Less fuel will result in less fire. It’s so easy a cave man could figure it out.
Arson was a significant issue last year, over 200 arrested, as well as environmental laws against clearing brush from around homes to protect small animal habitat.
The devastating 2009 Black Saturday bushfires destroyed 1.1 million acres of land, at least 3,500 buildings and killed 178 people. Most of the fires were in the southern state of Victoria.
The Victorian government of the day quickly called a Royal Commission inquiry into the causes and reasons for the disaster.
After 2 years the Royal Commission handed down its report containing numerous recommendations, a major one of which was that cool burning should be undertaken at the annual level of 390,000Ha in Victoria.
The Victorian Labor government unequivocally adopted that key recommendation.
The subsequent cool burning record for Victoria is as follows:
2014/15 353,326Ha 91%
2015/16 197,940Ha 51%
2016/17 125,052Ha 32%
2017/18 74,728Ha 19%
2018/19 130,000Ha 33%
And then, surprise surprise, we have the devastating 2019/20 bushfire season.
All this occurred on the watch of Labor Premier Andrews, who is still in office today. What culpability does the failed performance of the Victorian State have?
Oh thats right, its Climate Change.
Fires in Australia are normal. They occur after wetter years where fuel build-up is allowed. In the 1890s, I think, 5 million acres burned in southern Australia because that region has wet winters and hot dry summers in a normal year. Another bad fire was in 1939 in NSW and Victoria. 1950s had bad fires Qld because that decade was a series of wet years with fuel build- up. Once broad-acre farming began fires were easier to contain with fire breaks. Reducing burning regimes leads to hotter ones that o more damage.
Australia has a policy of carbon farming to offset CO2 emissions.They have given tax breaks to people who increase the amount of carbon (aka tinder) stored in their land. Check out the negative CO2 output since 2009 in forestry unsder Sectors>>4 Land Use, Land-Use Change and Forestry UNFCCC
https://ageis.climatechange.gov.au/NGGITrend.aspx
If forestry is taking up 50000 gigatonnes of CO2 but only producing 5000 gigatonnes of CO2 equivalent timber then there is 45000 gigatonnes of CO2 equivalent take up- making tens of thousands of gigatonnes of dry weight timber.
In my opinion, the forest fires a couple of years ago are partly as a result of a decade of forestry and land mismanagement.