.

  • Written by Trent Penman, Associate professor, University of Melbourne
Firefighters conduct property protection as a bushfire approaches homes at Woodford NSW, Friday, November 8, 2019. Calls for more controlled burning are common after a major bushfire. DAN HIMBRECHTS/AAP

As sure as night follows day, this week’s bushfires prompted inevitable debate about whether fire authorities should have carried out more hazard reduction burning, and whether opposition from conservationists prevented this.

There are two key points to remember when we consider these questions. First, the impact on human life and property - not the impact on the environment - is the number one concern in the minds of fire officials when deciding whether to conduct a controlled burn. Second, and perhaps more importantly, evidence shows increasing the frequency or area of controlled burns does not necessarily reduce the bushfire risk.

In fact, during extreme fire danger conditions, reduced fuel loads - such as those achieved through hazard reduction burning - do little to moderate bushfire behaviour.

Firefighters protecting homes near Woodford, NSW as a bushfire approaches. AAP

Officals under heat to cut fuel loads

Hazard reduction burning, also known as prescribed or controlled burning, is primarily used to prevent the spread of bushfires by reducing the build-up of flammable fuel loads such as leaf litter, grasses and shrubs.

Authorities routinely come under pressure to reduce bushfire fuel loads - especially in the wake of a bushfire crisis like the one seen on the east coast in recent days.

Media and mining magnate Kerry Stokes this week called for more controlled burning, saying this was a more pressing concern than climate change in dealing with bushfires.

And Nationals MP Barnaby Joyce reportedly lashed out at the Greens and others for purportedly opposing controlled burning and land clearing, claiming “there is all this bureaucracy that stands in the way of people keeping their place safe”.

The hazards of hazard reduction

Nationals MP Barnaby Joyce this week said ‘bureaucracy’ was getting in the way of rural landowners conducting hazard reduction on their properties. Lukas Coch/AAP

Bushfire hazard reduction is not as simple as dropping a match indiscriminately and standing back to watch the landscape burn. Fire agencies must assess the risks and manage the potential impacts. These assessments are made in the years and months prior to the burn, as well as on the day.

Fire authorities invest significant time preparing for a controlled burn program. They work with communities to develop a plan and a rigorous process guides how, where and when the burns will be undertaken.

Protecting human life and property from the effects of a burn is the first priority, and by far represents the greatest challenge. Other impacts are also assessed in the process. These include effects on the environment, Indigenous and European cultural assets and sporting events.


Read more: Mr Morrison, I lost my home to bushfire. Your thoughts and prayers are not enough


Despite extensive planning, over the past decade prescribed burns have escaped containment lines and destroyed houses, such as at Margaret River in Western Australia in 2013 and Lancefield, Victoria in 2015. To prevent a repeat of this, policies require burns only proceed when the weather is suitable not just on the day, but for three to five days afterwards. This has meant many burns do not go ahead or are delayed for years.

Smoke from fires can increase mortality and hospitalisation rates, and so the effect on human health is playing an increasing role in whether to burn or not. Viticulture concerns have also delayed burns because smoke can also destroy grapes used in wine production.

Thick smoke blankets Sydney Harbour in May 2019 after hazard reduction burns. AAP

Controlled burns may not slow bushfires

Even if we were to carry out more controlled burns, it does not necessarily follow that bushfire risk would be reduced.

Controlled burns do not remove all fuels from an area. And forests accumulate fuel at different rates - some return to their pre-burn fuel loads in as few as three years.


Read more: 12 simple ways you can reduce bushfire risk to older homes


Our research has shown controlled burning was likely to have reduced the area later burnt by bushfires in only four of 30 regions examined in New South Wales, Victoria, South Australia and the ACT.

Evidence from a range of studies demonstrates fuel loads can significantly modify fire behaviour under benign weather conditions. But reduced fuel loads do little for bushfire mitigation under extreme fire weather and in times of drought.

A burnt-out structure on a property devastated by bushfires at Coutts Crossing in Northern NSW, November 2019. Jason O'Brien/AAP

Looking to the future

Evidence is mounting of increased bushfire frequency and extent in both Australia and the US - a situation predicted to worsen under climate change. Changing weather patterns mean opportunities for controlled burning will likely diminish further. Coupled with expanding populations in high fire-risk areas, Australia’s fire agencies - among the best in the world - have a challenging time ahead.


Read more: How we plan for animals in emergencies


In future, we must think beyond traditional approaches to fire management. Acknowledging the role of climate change in altering natural hazards and the impact they have on humans and the environment is the first step. Communities should also be at the centre of decisions, so they understand and act on the risks.

Trent Penman receives funding from the Bushfire and Natural Hazards CRC and several state fire agencies.

Kate Parkins receives funding from The Victorian Department of Environment, Land, Water and Planning (DELWP), The New South Wales Department for Planning, Industry and Environment (DPIE).

Sarah McColl-Gausden receives funding from the Victorian Department of Environment, Land, Water and Planning.

Authors: Trent Penman, Associate professor, University of Melbourne

Read more http://theconversation.com/a-surprising-answer-to-a-hot-question-controlled-burns-often-fail-to-slow-a-bushfire-127022

Boosting Your Child’s Learning through Play

Being a parent is probably the highest responsibility one has in a lifetime. Once it happens, it becomes ongoing and keeps posing new challenges to us. Of course, it may seem easy from some perspe...

Diana Smith - avatar Diana Smith

Different ideas of Christmas Gifts to give to your beloved ones

"CHRISTMAS GIFTS – one of the best festival gifts to give to your closed ones. Find Christmas presents for everybody on your checklist. Christmas is now here, and if that you haven't got a hop on ...

News Company - avatar News Company

The Ultimate Guide to Sneakers and Sneaker Brands

When it comes to finding the perfect pair of sneakers, it can be hard to know where to start. Finding the right pair for any kind of occasion can be difficult, so brushing up on your knowledge of sn...

News Company - avatar News Company

View from The Hill: Morrison won't have a bar of public service intrusions on government's power

Scott Morrison has rejected or sidelined a number of recommendations from the long-awaited Thodey review. AAP/Paul BravenScott Morrison has rejected or sidelined a number of recommendations from the l...

Michelle Grattan, Professorial Fellow, University of Canberra - avatar Michelle Grattan, Professorial Fellow, University of Canberra

VIDEO: Michelle Grattan reflects on the year in politics

For their last video for the year, University of Canberra Vice-Chancellor Deep Saini and Michelle Grattan look backwards to the big issues which have shaped political discourse. They discuss the surpr...

Michelle Grattan, Professorial Fellow, University of Canberra - avatar Michelle Grattan, Professorial Fellow, University of Canberra

Choosing a Heavy Weighted Bathmats

Decorating your bathroom doesn’t finish with the paint choice or tile colours. You can change the whole room with the change of your towel set. There are no rules that say that you need to have a ...

News Company - avatar News Company

God as man, man as God: no wonder many Christian men today are having a masculinity crisis

How men saw God shaped how they saw themselves, and in turn, how they saw women. WikimediaThis article is part of our Gender and Christianity series. To understand contemporary Christian ideas about...

William Loader, Emeritus Professor of New Testament at Murdoch University, Murdoch University - avatar William Loader, Emeritus Professor of New Testament at Murdoch University, Murdoch University

Australia needs a national crisis plan, and not just for bushfires

Bushfires aren't the only catastrophic emergency Australia is likely to see. AAP Image/Mick TsikasCalls are growing for a national bushfire plan, including from former prime minister Malcolm Turnbull...

Andrew Gissing, General Manager, Risk Frontiers, Adjunct Fellow, Macquarie University - avatar Andrew Gissing, General Manager, Risk Frontiers, Adjunct Fellow, Macquarie University

Your Christmas shopping could harm or help the planet. Which will it be?

Many Australian consumers are concerned at the environmental impact of their shopping habits, especially at Christmas. AAPAustralian shoppers are set to spend $52.7 billion this Christmas. In the word...

Louise Grimmer, Senior Lecturer in Marketing, Tasmanian School of Business and Economics, University of Tasmania - avatar Louise Grimmer, Senior Lecturer in Marketing, Tasmanian School of Business and Economics, University of Tasmania

Right-swipes and red flags – how young people negotiate sex and safety on dating apps

For many young people, app dating is just part of regular dating life. freestocks.org/UnsplashPopular commentary on dating apps often associates their use with “risky” sex, harassment and ...

Kath Albury, Professor of Media and Communication, Faculty of Health, Arts and Design, Swinburne University of Technology - avatar Kath Albury, Professor of Media and Communication, Faculty of Health, Arts and Design, Swinburne University of Technology

Bougainville has voted to become a new country, but the journey to independence is not yet over

The Autonomous Region of Bougainville, a chain of islands that lie 959 kilometres northwest of Papua New Guinea’s capital, Port Moresby, has voted unequivocally for independence. The referendum...

Anna Powles, Senior Lecturer in Security Studies, Massey University - avatar Anna Powles, Senior Lecturer in Security Studies, Massey University

Comfortable Footwear That'll Get You Through From Day To Night In Style

When you are choosing your footwear, you need to make sure that you are choosing something that is going to be comfortable. This is especially important if you are going to be wearing your shoes a...

Rosana Beechum - avatar Rosana Beechum

How to Have a Peaceful Retirement

Retirement is the time to treat yourself after a lifetime of working, to complete your bucket list and to spend time with the people that you care for. However, having a peaceful retirement can be d...

News Company - avatar News Company

Friday essay: eco-disaster films in the 21st century - helpful or harmful?

A scene from the 2017 film Geostorm: many societies have historically attempted to deal with collective trauma by replaying and restaging it in art. Warner Bros., Electric Entertainment, Rat Pac-Dune ...

Ari Mattes, Lecturer in Communications and Media, University of Notre Dame Australia - avatar Ari Mattes, Lecturer in Communications and Media, University of Notre Dame Australia

A new study shows an animal's lifespan is written in the DNA. For humans, it's 38 years

A genetic "clock" lets scientists estimate how long extinct creatures lived. Wooly mammoths could expect around 60 years. Australian MuseumHumans have a “natural” lifespan of around 38 yea...

Benjamin Mayne, Molecular biologist and bioinformatician, CSIRO - avatar Benjamin Mayne, Molecular biologist and bioinformatician, CSIRO

Vital Signs: Australia's wafer-thin surplus rests on a mine disaster in Brazil

On Monday the Australian government will release the Mid-Year Economic and Fiscal Outlook (MYEFO). This will – as required by the Charter of Budget Honesty – provide an update on the key a...

Richard Holden, Professor of Economics, UNSW - avatar Richard Holden, Professor of Economics, UNSW

Don't believe the stereotype: these 5 charts show our democracy is safe in the hands of future voters

Almost 900 school kids, aged 12 to 17, were surveyed. ShutterstockA new, ongoing survey on how young Australians understand and imagine their democracy is already challenging long-held stereotypes. ...

Mark Evans, Professor of Governance and Director of Democracy 2025 - bridging the trust divide at Old Parliament House, University of Canberra - avatar Mark Evans, Professor of Governance and Director of Democracy 2025 - bridging the trust divide at Old Parliament House, University of Canberra

Private health insurance premiums should be based on age and health status

Policy changes have failed to stop young people dropping their private health insurance. ShutterstockPrivate health insurance has come under intense scrutiny in recent months, as it becomes clear heal...

Francesco Paolucci, Associate Professor; Head of Health Policy Program, Sir Walter Murdoch School of Public Policy and International Affairs, University of Newcastle - avatar Francesco Paolucci, Associate Professor; Head of Health Policy Program, Sir Walter Murdoch School of Public Policy and International Affairs, University of Newcastle

Knowledge is a process of discovery: how constructivism changed education

According to constructivists, we truly understand something when we filter it through our senses and interactions. from shutterstock.comThis is the second of two essays exploring key theories – ...

Luke Zaphir, Researcher for the University of Queensland Critical Thinking Project; and Online Teacher at Education Queensland's IMPACT Centre, The University of Queensland - avatar Luke Zaphir, Researcher for the University of Queensland Critical Thinking Project; and Online Teacher at Education Queensland's IMPACT Centre, The University of Queensland

Sick and Tired of Your Dead End Job? Try Teaching!

Tired of the same old grind at the office? Want an opportunity to impact lives both in your community and around the world? Do you love to travel and have new experiences? Teaching English is the perfect job for you! All you need is a willingness to ...

News Company - avatar News Company

The Impact of an Aging Population in Australia

There’s an issue on the horizon that Australia needs to prepare for. The portion of elderly citizens that make up the country’s overall population is increasing, and we might not have the infrastructure in place to support this. Australians h...

News Company - avatar News Company

LifeStyle

Boosting Your Child’s Learning through Play

Being a parent is probably the highest responsibility one has in a lifetime. Once it happens, it...

Different ideas of Christmas Gifts to give to your beloved ones

"CHRISTMAS GIFTS – one of the best festival gifts to give to your closed ones. Find Christmas pr...

How to Have a Peaceful Retirement

Retirement is the time to treat yourself after a lifetime of working, to complete your bucket list...

Latest Wednesday Lotto Results

Wednesday Lotto draw 3917 Lucky numbers for this draw were 43 followed by 25. The rest of the...