The science is clear: we have to start creating our low-carbon future today


Alan Finkel, Office of the Chief Scientist

This week’s release of the special report from the Intergovernmental Panel on Climate Change (IPCC) has put scientific evidence on the front page of the world’s newspapers.

As Australia’s Chief Scientist, I hope it will be recognised as a tremendous validation of the work that scientists do.

The people of the world, speaking through their governments, requested this report to quantify the impacts of warming by 1.5℃ and what steps might be taken to limit it. They asked for the clearest possible picture of the consequences and feasible solutions.




Read more:
The UN’s 1.5°C special climate report at a glance


It is not my intention in this article to offer a detailed commentary on the IPCC’s findings. I commend the many scientists with expertise in climate systems who have helped Australians to understand the messages of this report.

My purpose is to urge all decision-makers – in government, industry and the community – to listen to the science.

Focus on the goal

It would be possible for the public to take from this week’s headlines an overwhelming sense of despair.

The message I take is that we do not have time for fatalism.

We have to look squarely at the goal of a zero-emissions planet, then work out how to get there while maximising our economic growth. It requires an orderly transition, and that transition will have to be managed over several decades.

That is why my review of the National Electricity Market called for a whole-of-economy emissions reduction strategy for 2050, to be in place by the end of 2020.




Read more:
The Finkel Review at a glance


We have to be upfront with the community about the magnitude of the task. In a word, it is huge.

Many of the technologies in the IPCC’s most optimistic scenarios are at an early stage, or conceptual. Two that stand out in that category are:

  • carbon dioxide removal (CDR): large-scale technologies to remove carbon dioxide from the atmosphere.

  • carbon capture and sequestration (CCS): technology to capture and store carbon dioxide from electricity generation.

It will take a decade or more for these technologies to be developed to the point at which they have proven impact, then more decades to be widely deployed.

The IPCC’s pathways for rapid emissions reduction also include a substantial role for behavioural change. Behavioural change is with us always, but it is incremental.

Driving change of this magnitude, across all societies, in fundamental matters like the homes we build and the foods we eat, will only succeed if we give it time – and avoid the inevitable backlash from pushing too fast.

The IPCC has made it clear that the level of emissions reduction we can achieve in the next decade will be crucial. So we cannot afford to wait.

Many options

No option should be ruled off the table without rigorous consideration.

In that context, the Finkel Review pointed to a crucial role for natural gas, particularly in the next vital decade, as we scale up renewable energy.

The IPCC has made the same point, not just for Australia but for the world.

The question should not be “renewables or coal”. The focus should be on atmospheric greenhouse emissions. This is the outcome that matters.

Denying ourselves options makes it harder, not easier, to get to the goal.

There also has to be serious consideration of other options modelled by the IPCC, including biofuels, catchment hydroelectricity, and nuclear power.

My own focus in recent months has been on the potential for clean hydrogen, the newest entrant to the world’s energy markets.




Read more:
How hydrogen power can help us cut emissions, boost exports, and even drive further between refills


In future, I expect hydrogen to be used as an alternative to fossil fuels to power long-distance travel for cars, trucks, trains and ships; for heating buildings; for electricity storage; and, in some countries, for electricity generation.

We have in Australia the abundant resources required to produce clean hydrogen for the global market at a competitive price, on either of the two viable pathways: splitting water using solar and wind electricity, or deriving hydrogen from natural gas and coal in combination with carbon capture and sequestration.

Building an export hydrogen industry will be a major undertaking. But it will also bring jobs and infrastructure development, largely in regional communities, for decades.

So the scale of the task is all the more reason to press on today – at the same time as we press on with mining lithium for batteries, clearing the path for electric vehicles, planning more carbon-efficient cities, and so much more.

There are no easy answers. I hope, through this and other reports, there are newly determined people ready to contribute to the global good.The Conversation

Alan Finkel, Australia’s Chief Scientist, Office of the Chief Scientist

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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Australia must embrace transformation for a sustainable future



File 20180618 85845 1xi7qyi.jpg?ixlib=rb 1.1

Judy van der Velden/Flickr, CC BY-NC

Shirin Malekpour, Monash University

Last Friday, the Australian government released its first report on our progress towards meeting the United Nations’ Sustainable Development Goals by 2030.

These 17 goals are a call to action to ensure economic prosperity and social inclusion, while protecting the planet. They cover issues ranging from health to reducing inequalities and clean energy.

According to the report, Australia has made some steady progress towards most of our goals.




Read more:
In the quest to meet the SDGs, there’s a danger that some may be left behind


However, to achieve the goals in just 12 years from now, we need transformative actions. These are missing in the report. Without a strong vision and new models of partnership between government, industry and communities, we will not meet the 2030 deadline.

What the report says

In 2015, most of the world’s nations signed up to the United Nation’s 2030 Agenda. In July this year, Australia will present its first voluntary review of progress towards the goals at the UN. These reviews are a crucial component of accountability.

Australia’s Voluntary National Review (for which I facilitated a consultation workshop to give input from the university sector) is a showcase of policies, actions and initiatives from across different sectors that are, in the report’s language, “relevant” to achieving the goals.

The report highlights that Australia is a prosperous and generally healthy country. But it also acknowledges significant challenges, such as improving the health and prosperity of Australia’s Aboriginal and Torres Strait Islander peoples, and helping workers in the resources or manufacturing sectors who are facing technological and industrial transitions.




Read more:
Climate action is the key to Australia achieving the Sustainable Development Goals


The report highlights that local councils, statutory authorities, businesses and universities are taking actions that are explicitly aligned with the global goals. For example, a number of Australian universities have signed a commitment to the goals and are including the 2030 Agenda in their curricula.

However, no sector has fundamentally changed its practices in response to the Sustainable Development Goals, nor embedded the goals into its core business.

At the national level, there has been limited specific engagement with the goals. Most of the national policies outlined in the report were developed for other reasons, and some have been around for years or decades. Examples are the National Disability Strategy, which dates back to pre-2010, or the National Drought Policy, which began in 1992. In other words, at the national level, the report emphasises what we have already been doing – not new initiatives explicitly related to the goals.

Notwithstanding success stories from across different sectors, the reality is that we will not be able to meet the goals in just 12 years on a business-as-usual trajectory. Instead, we need transformative plans across all sectors.

What is transformative change?

Sustainable development, as opposed to conventional development, involves big systemic transformations. Let’s use the example of clean energy.

Taking carbon out of our energy system is not simply about using wind and solar instead of coal. It involves big changes in how we consume energy, in manufacturing technologies and in the ways governments help (or hinder) the adoption of new technologies and practices. It requires systemic transformation, rather than incremental improvements.

Research into systemic transformation has identified a range of factors for making change happen. Two critical factors are creative decision-making and strong partnerships across disciplines and sectors. If we are serious about achieving the Sustainable Development Goals by 2030, we need to act now.

Transformative decision-making

Conventional decision-making favours the status quo and is largely risk-averse. It can cope with small incremental changes, but not big ones. In transport, for instance, we often tend to augment or replicate existing infrastructure – building another highway, for example – rather than innovating by trying to get people out of their cars.

Conventional decision-making also prefers to react: we often wait for a crisis situation and then quickly respond. This almost always favours short-term over long-term benefits.

Transformative decision-making, on the other hand, is proactive and takes deliberate actions to shape a desired future. It works toward a long-term vision and doesn’t shy away from uncertainty and complexity along the way.

As Australia’s review correctly acknowledges, the Sustainable Development Goals are all about “longstanding, complex policy challenges with no simple solutions”. Solving complex problems requires a great deal of innovation and experimentation. We need governments, businesses and communities to be willing to try new things, even if they occasionally fail.

Developing partnerships

Improving the lives of people and the planet requires myriad skills, tapping into various networks and reaching out to all segments of society.

Universities, for instance, often play a key role in analysing problems, developing new solutions and providing the evidence base that a solution actually works. But it is only through partnering with communities, businesses and policy organisations that they can put these solutions into practice.




Read more:
Universities must act now on sustainability goals


The Voluntary National Review has highlighted the role of cross-sectoral partnerships. What is missing is a plan for fostering the partnerships that can enable substantial change in just 12 years.

The ConversationAs Australia prepares to present our progress report at the 2018 UN High Level Political Forum in July, we need more critical assessment of our performance. How can we start doing things differently to be able to celebrate achieving these ambitious global goals in 2030?

Shirin Malekpour, Research Leader in Strategic Planning and Futures Studies, Monash Sustainable Development Institute, Monash University

This article was originally published on The Conversation. Read the original article.

The future is fenced for Australian animals



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Mala, also known as rufous hare-wallabies, will be protected behind an enormous cat-proof fence.
Donald Hobern/Flickr, CC BY-SA

Michael Bode, The University of Queensland

Many of Australia’s mammals spend their entire lives imprisoned, glimpsing the outside world through tall chain-link fences and high-voltage wires. There are dozens of these enclosures across Australia. Many are remote, standing alone in the endless expanse of inland Australia, but others are on the outskirts of our largest cities – Melbourne, Perth, Canberra.

Every year there are more of them, the imprisoned population growing, while the wild populations outside dwindle. These are Australia’s conservation fences.




Read more:
Let’s move the world’s longest fence to settle the dingo debate


The captives within our conservation fences are adorable – floppy-eared bilbies, tiny hare-wallabies, long-tongued numbats – and they all share an extreme susceptibility to introduced predators. At least 68 native mammal species cannot exist in the wild if either foxes or cats are present. Many of these species once numbered in the millions, ranging from the woodlands of Queensland to the deserts of Western Australia, but predation has driven them to the brink of extinction.

Fences offer these species a future in the wild, and conservation groups have risen to the challenge. Last week, the Australian Wildlife Conservancy completed a new cat-proof fence in their Newhaven Sanctuary, the largest conservation fence ever constructed.

Fences are extraordinarily successful

Make no mistake, these conservation fences work. Species that wilt at the sight of a fox, that have been exterminated from every corner of the Australian mainland, will explode in numbers behind fences. Along with offshore islands, inside these fences are the only places in Australia where these species can prosper – a few hundred square kilometres of safety, surrounded by 7.6 million lethal square kilometres.

Environmentalists have never particularly liked fences. Rather than hide behind walls, they repeatedly took the fight to the cats and foxes on the outside.

Their tactics have been diverse, innovative and brutal. Managers have rained bullets from helicopters and poison baits from planes. They have set cunning snares and traps, mimicked the smell and sound of their enemies, and have turned landscapes to ash with wildfire.

Nothing has worked for the most threatened marsupials. Some of the largest and most expensive management campaigns in Australian conservation history have ended in exhaustion and stalemate, and with a retreat back behind the fences.

Fences were once a source of vehement debate in conservation circles. Should they be permanent? Are fenced populations wild or captive? Should they contribute to species’ conservation status?

These arguments have effectively been abandoned. Scientific studies and painful experience has proven fences and offshore islands to be the only reliable method of protecting predator-threatened species http://www.wildliferesearchmanagement.com.au/Final%20Report_0609.pdf. In place of these debates, conservation organisations and governments have turned to more practical questions of fence height, electric wire voltage and skirt depth.

So now, on average, Australians are building a new fence every year, some of them truly enormous. The just-completed fence at Newhaven encloses a staggering 10,000 hectares of red sand and spinifex. By the time the project is complete, this fence will be home to 11 different threatened mammal species.

And Australia is not alone: around the world, from New Zealand to Hawaii to South Africa, an archipelago of fences is emerging from an ocean of predators. It is one of the great achievements of modern conservation and has already averted the extinction of critically endangered species. Although it’s much smaller than our network of protected areas, it offers refuge to species that are long-gone from our national parks and wilderness areas.

Red foxes have been extraordinarily successful in Australia.
Harley Kingston/Flickr, CC BY

A troubling pattern

However, in recent years a concerning pattern has begun to emerge. While the number and size of fences continue to increase, the number of new species being protected has stalled. In fact, the last five fences haven’t included any new species – they have only offered additional protection to species that were already protected behind existing fences https://www.nature.com/articles/s41559-017-0456-4.

As an example, the first two marsupials planned for introduction behind the Newhaven fence will be the mala (Lagorchestes hirsutus) and the burrowing bettong (Bettongia lesueur). These two species undeniably deserve more protection. Both are highly susceptible to foxes and cats and will derive tremendous benefit from the protection of this enormous fence. However, both species are already found elsewhere behind fences (four different fences for burrowing bettongs). Meanwhile, yet-to-be-published research from the National Environmental Science Program has found 41 other species that are desperately vulnerable to introduced predators are not protected by any fence.

This problem is not new to conservation. In the 1990s, Australian researchers suddenly realised that our national park system was failing to protect the full range of Australian ecosystems. Despite our best efforts, we had created a system of reserves that was biased towards mountainous landscapes and deserts, and away from the fertile valley floors. The solution was to create new national parks using systematic and mathematical methods.

This discovery – the theory of systematic conservation planning – revolutionised global conservation. In 2018, conservation fences need their own systematic revolution.

Unfortunately, the national park system had natural advantages that fences lack. The vast majority of Australia’s protected areas belong to the state and federal governments. The centralised nature of the protected area network is perfect for systematic thinking and top-down optimisation – picture the Soviet Union’s Politburo. In contrast, the conservation fencing sector is diverse and decentralised – picture the third day of Woodstock.




Read more:
All cost, little benefit: WA’s barrier fence is bad news for biodiversity



Fences are built by governments at the state, federal and municipal levels, by multimillion-dollar NGOs like the Australia Wildlife Conservancy, by tiny local environmentalist groups and by profit-making corporations. This diversity is a fundamental strength of the fence network, giving it access to a spectrum of funding and ideas. But it makes it almost impossible to plan in a systematic manner. You can’t tell a small bilby conservation group in western Queensland that they should protect the central Australian rock-rat instead (Zyzomys pedunculatus). It doesn’t necessarily matter to them that bilbies are already protected behind four different fences and the rock-rat has none.

While conservation science tries to work this problem out, new and larger fences will continue to be built at an accelerating rate into the foreseeable future. True, the absence of coordination will make mathematicians break their slide rules, but each fence will do its job. The furry denizens will hop, and scurry, and bounce around, heedless of their precarious safety.

The ConversationAnd for us, from the outside looking in, these fences will help us forget the parlous state of Australian marsupial conservation. It will be possible to forget our record-breaking rate of extinctions, to forget the empty forests and deserts, and to imagine what a bushwalk might have been like before Europeans unleashed foxes and cats onto Australia.

Michael Bode, Associate Professor of Mathematics, The University of Queensland

This article was originally published on The Conversation. Read the original article.

How protons can power our future energy needs



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The proton battery, connected to a voltmeter.
RMIT, Author provided

John Andrews, RMIT University

As the world embraces inherently variable renewable energy sources to tackle climate change, we will need a truly gargantuan amount of electrical energy storage.

With large electricity grids, microgrids, industrial installations and electric vehicles all running on renewables, we are likely to need a storage capacity of over 10% of annual electricity consumption – that is, more than 2,000 terawatt-hours of storage capacity worldwide as of 2014.

To put that in context, Australia’s planned Snowy 2.0 pumped hydro storage scheme would have a capacity of just 350 gigawatt-hours, or roughly 0.2% of Australia’s current electricity consumption.




Read more:
Tomorrow’s battery technologies that could power your home


Where will the batteries come from to meet this huge storage demand? Most likely from a range of different technologies, some of which are only at the research and development stage at present.

Our new research suggests that “proton batteries” – rechargeable batteries that store protons from water in a porous carbon material – could make a valuable contribution.

Not only is our new battery environmentally friendly, but it is also technically capable with further development of storing more energy for a given mass and size than currently available lithium-ion batteries – the technology used in South Australia’s giant new battery.

Potential applications for the proton battery include household storage of electricity from solar panels, as is currently done by the Tesla Powerwall.

With some modifications and scaling up, proton battery technology may also be used for medium-scale storage on electricity grids, and to power electric vehicles.

The team behind the new battery. L-R: Shahin Heidari, John Andrews, proton battery, Saeed Seif Mohammadi.
RMIT, Author provided

How it works

Our latest proton battery, details of which are published in the International Journal of Hydrogen Energy, is basically a hybrid between a conventional battery and a hydrogen fuel cell.

During charging, the water molecules in the battery are split, releasing protons (positively charged nuclei of hydrogen atoms). These protons then bond with the carbon in the electrode, with the help of electrons from the power supply.

In electricity supply mode, this process is reversed: the protons are released from the storage and travel back through the reversible fuel cell to generate power by reacting with oxygen from air and electrons from the external circuit, forming water once again.

Essentially, a proton battery is thus a reversible hydrogen fuel cell that stores hydrogen bonded to the carbon in its solid electrode, rather than as compressed hydrogen gas in a separate cylinder, as in a conventional hydrogen fuel cell system.

Unlike fossil fuels, the carbon used for storing hydrogen does not burn or cause emissions in the process. The carbon electrode, in effect, serves as a “rechargeable hydrocarbon” for storing energy.

What’s more, the battery can be charged and discharged at normal temperature and pressure, without any need for compressing and storing hydrogen gas. This makes it safer than other forms of hydrogen fuel.

Powering batteries with protons from water splitting also has the potential to be more economical than using lithium ions, which are made from globally scarce and geographically restricted resources. The carbon-based material in the storage electrode can be made from abundant and cheap primary resources – even forms of coal or biomass.




Read more:
A guide to deconstructing the battery hype cycle


Our latest advance is a crucial step towards cheap, sustainable proton batteries that can help meet our future energy needs without further damaging our already fragile environment.

The time scale to take this small-scale experimental device to commercialisation is likely to be in the order of five to ten years, depending on the level of research, development and demonstration effort expended.

Our research will now focus on further improving performance and energy density through use of atomically thin layered carbon-based materials such as graphene.

The ConversationThe target of a proton battery that is truly competitive with lithium-ion batteries is firmly in our sights.

John Andrews, Professor, School of Engineering, RMIT University

This article was originally published on The Conversation. Read the original article.

Semitransparent solar cells: a window to the future?


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Looking through semitransparent cells – one day these could be big enough to make windows.
UNSW, Author provided

Matthew Wright, UNSW and Mushfika Baishakhi Upama, UNSW

Can you see a window as you are reading this article?

Windows have been ubiquitous in society for centuries, filling our homes and workplaces with natural light. But what if they could also generate electricity? What if your humble window could help charge your phone, or boil your kettle?

With between 5 billion and 7 billion square metres of glass surface in the United States alone, solar windows would offer a great way to harness the Sun’s energy. Our research represents a step toward this goal, by showing how to make solar panels that still let through enough light to function as a window.




Read more:
Solar is now the most popular form of new electricity generation worldwide


The economics of renewable energy are becoming increasingly favourable. In Australia, and many other parts of the world, silicon solar cells already dominate the rooftop market.
Rooftop solar power offers an increasingly cheap and efficient way to generate electricity.

But while great for roofs, these silicon modules are opaque and bulky. To design a solar cell suitable for windows, we have to think outside the box.

When we put a solar panel on a roof, we want it to absorb as much sunlight as possible, so that it can generate the maximum amount of power. For a window, there is inevitably a trade-off between absorbing light to turn into electricity, and transmitting light so we can still see through the window.

When thinking about a cell that could be fitted to a window, one of the key parameters is known as the average visible transmittance (AVT). This is the percentage of visible light (as opposed to other wavelengths, like infrared or ultraviolet) hitting the window that travels through it and emerges on the other side.

Semitransparent solar cells convert some sunlight into electricity, while also allowing some light to pass through.
Author provided

Of course we don’t want the solar window to absorb so much light that we can longer see out of it. Nor do we want it to let so much light through that it hardly generates any solar power. So scientists have been trying to find a happy medium between high electrical efficiency and a high AVT.

A matter of voltage

An AVT of 25% is generally considered a benchmark for solar windows. But letting a quarter of the light travel through the solar cell makes it hard to generate a lot of current, which is why the efficiency of semitransparent cells has so far been low.

But note that electrical power depends on two factors: current and voltage. In our recent research, we decided to focus on upping the voltage. We carefully selected new organic absorber materials that have been shown to produce high voltage in non-transparent cells.

When placed in a semitransparent solar cell, the voltage was also high, as it was not significantly lowered by the large amount of transmitted light. And so, although the current was lowered, compared to opaque cells, the higher voltage allowed us to achieve a higher efficiency than previous semitransparent cells.

Having got this far, the key question is: what would windows look like if they were made of our new semitransparent cells?

Do you see what I see?

If your friend is wearing a red shirt, when you view them through a window, their shirt should appear red. That seems obvious, as it will definitely be the case for a glass window.

But because semitransparent solar cells absorb some of the light we see in the visible spectrum, we need to think more carefully about this colour-rendering property. We can measure how well the cell can accurately present an image by calculating what’s called the colour rendering index, or CRI. Our investigation showed that changing the thickness of the absorbing layer can not only affect the electrical power the cell can produce, but also changes its ability to depict colours accurately.

A different prospective approach, which can lead to excellent CRIs, is to replace the organic absorber material with one that absorbs energy from the sun outside the visible range. This means the cell will appear as normal glass to the human eye, as the solar conversion is happening in the infrared range.

However, this places limitations on the efficiency the cells can achieve as it severely limits the amount of power from the sun that can be converted to electricity.

What next?

So far we have created our cells only at a small, prototype scale. There are still several hurdles in the way before we can make large, efficient solar windows. In particular, the transparent electrodes used to collect charge from these cells can be brittle and contain rare elements, such as indium.




Read more:
Solar power alone won’t solve energy or climate needs


If science can solve these issues, the large-scale deployment of solar-powered windows could help to bolster the amount of electricity being produced by renewable technologies.

The ConversationSo while solar windows are not yet in full view, we are getting close enough to glimpse them.

Matthew Wright, Postdoctoral Researcher in Photovoltaic Engineering, UNSW and Mushfika Baishakhi Upama, PhD student [Photovoltaics & Renewable Energy Engineering], UNSW

This article was originally published on The Conversation. Read the original article.

To fight the catastrophic fires of the future, we need to look beyond prescribed burning



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AAP Image/ Darren Pateman

James Furlaud, University of Tasmania and David Bowman, University of Tasmania

California is burning – a sentence we’ve heard far too often this year. Sydney is currently on bushfire alert, as firefighters battle a fire in the Hunter Valley region and temperatures are set to top 40℃.

A cocktail of factors, from climate change to centuries of ignoring indigenous burning practises, means that catastrophic fires are likely to become more common.


Read more: Dry winter primes Sydney Basin for early start of bushfire season


One of Australia’s favourite fire prevention measures is prescribed burning – using carefully controlled fires to clear out flammable materials. We’re almost obsessed with it. Indeed, it seems the outcome of every major inquiry is that we need to do more of it.

The Royal Commission inquiry that followed Victoria’s 2009 Black Saturday fires recommended that 5% of all public land in Victoria be treated per year – a doctrine that was subsequently dropped due to impracticality.

Yet our research, published today in the International Journal of Wildland Fire, modelled thousands of fires in Tasmania and found that nearly a third of the state would have to be burned to effectively lower the risk of bushfires.

The question of how much to burn and where is a puzzle we must solve, especially given the inherent risk, issues caused by smoke smoke and shrinking weather windows for safe burning due to climate change.

Why use computer simulations?

The major problem fire science faces is gathering data. Landscape-scale experiments involving extreme fire are rare, for obvious reasons of risk and cost. When a major bushfire happens, all the resources go into putting it out and protecting people. Nobody has the time to painstakingly collect data on how fast it is moving and what it is burning. We are therefore restricted to a few limited data sources to reconstruct the behaviour and impact of fire: we can analyse the scar on the landscape after a fire, look at case studies, or run simulations of computer models.

Most research on the effectiveness of prescribed burning has been at a local scale. We need to start thinking bigger: how can we mitigate the effect of multiple large fires in a region like Tasmania or Southeastern Australia? What is the cumulative effect of different prescribed burning strategies?

A large fuel reduction burn off on Hobart’s eastern shore.
Flickr/Mike Rowe, CC BY-NC

To answer these questions, we create models using mathematical equations to simulate the behaviour of fires across actual landscapes. These models include the effects of vegetation type, terrain and fuel loads, under specific weather conditions. If we simulate thousands of these fires we can get an idea of where fire risk is the highest, and how effective prescribed burning is at reducing that risk.

The island of Tasmania offers the perfect study system. Self-contained, with a wide array of vegetation types and fire regimes, it offers an ideal opportunity to see how fire behaves across a diverse landscape. Perhaps more interestingly, the island contains large areas of flammable landscape surrounding globally unique ecosystems and numerous towns and villages. Obviously, we cannot set fire to all of Tasmania in real life, but computer simulations make it possible!

So, encouraged by the Tasmanian Fire Service, who initiated our research, we simulated tens of thousands of fires across Tasmania under a range of prescribed burning scenarios.

Prescribed fire can be effective, in theory

The first scenario we looked at was the best-case scenario: what happens if we perform prescribed burning on all the vegetation that can handle it, given theoretically unlimited resources? It is possible this approximates the sustained and skillful burning by Tasmanian Aboriginal peoples.

Wildfire simulations following this scenario suggested that such an approach would be extremely effective. Importantly, we saw significant reductions in fire activity even in areas where prescribed burning is impossible (for example, due to the presence of people).

Unfortunately, this best-case approach, while interesting from a theoretical perspective, would require prescribed burning over more than 30% of Tasmania in one year.

We also analysed the effects of 12 more realistic scenarios. These realistic plans were less than half as efficient as the best-case scenario at reducing fire activity.

On average, 3 hectares of prescribed burning would reduce wildfire extent by roughly 1ha in grasslands and dry forests.

In other flammable Tasmanian vegetation types like buttongrass sedgelands and heathlands, the reduction in wildfire was even smaller. This is obviously better than no prescribed burning, but it highlights the fact that this is a relatively inefficient tool, and given the costs and potential drawbacks, should be used only where it is most needed.

This is a fundamental conundrum of prescribed burning: though it is quite effective in theory, the extent to which we would need to implement it to affect fire behaviour across the entire state is completely unachievable.

Therefore, it is imperative that we not just blindly burn a pre-ordained fraction of the landscape. Rather, we must carefully design localised prescribed burning interventions to reduce risk to communities.

We need a multi-tool approach

Our study has shown that while prescribed burning can be quite effective in certain scenarios, it has serious constraints. Additionally, while we analysed these scenarios under bad fire weather, we were not able to analyse the kind of catastrophic days in which the effect of prescribed burning is seriously reduced, with howling dry winds and stupefying heat.

Unfortunately, due to climate change, we are going to see a lot more catastrophic days in the future in Tasmania and indeed globally.

In Hobart this is of particular concern, as the city is surrounded by tall, wet eucalypt forests that have had fifty years grow dense understoreys since the 1967 Black Tuesday fires. These have the potential to cause some of the most intense fires on the planet should conditions get dry enough. Prescribed burning is impossible in these forests.


Read more: Where to take refuge in your home during a bushfire


To combat fire risk we must take a multi-pronged approach that includes innovative strategies, such as designing new spatial patterns for prescribed burning, manually removing fuels from areas in which prescribed burning is not possible, improving the standards for buildings and defensible spaces, and most importantly, engaging the community in all of this.

The ConversationOnly by attacking this problem from multiple angles, and through close collaboration with the community and all levels of government, can we effectively face our fiery future.

James Furlaud, PhD Student in Fire Ecology, University of Tasmania and David Bowman, Professor, Environmental Change Biology, University of Tasmania

This article was originally published on The Conversation. Read the original article.

Scars left by Australia’s undersea landslides reveal future tsunami potential



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The Byron Scar, left behind by an undersea landslide. Colours indicate depths.
Samantha Clarke, Author provided

Samantha Clarke, University of Sydney; Hannah Power, University of Newcastle; Kaya Wilson, University of Newcastle, and Tom Hubble, University of Sydney

It is often said that we know more about the surface of other planets than we do about our own deep ocean. To overcome this problem, we embarked on a voyage on CSIRO’s research vessel, the Southern Surveyor, to help map Australia’s continental slope – the region of seafloor connecting the shallow continental shelf to the deep oceanic abyssal plain.

The majority of our seafloor maps depict most of the ocean as blank and featureless (and the majority still do!). These maps are derived from wide-scale satellite data, which produce images showing only very large features such as sub-oceanic mountain ranges (like those seen on Google Earth). Compare that with the resolution of land-based imagery, which allows you to zoom in on individual trees in your own neighbourhood if you want to.

But using a state-of-the art sonar system attached to the Southern Surveyor, we have now studied sections of the seafloor in more detail. In the process, we found evidence of huge underwater landslides close to shore over the past 25,000 years.

Generally triggered by earthquakes, landslides like these can cause tsumanis.

Into the void

For 90% of the ocean, we still struggle to identify any feature the size of, say, Canberra. For this reason, we know more about the surface of Venus than we do about our own ocean’s depths.

As we sailed the Southern Surveyor in 2013, a multibeam sonar system attached to the vessel revealed images of the ocean floor in unprecedented detail. Only 40-60km offshore from major cities including Sydney, Wollongong, Byron Bay and Brisbane, we found huge scars where sediment had collapsed, forming submarine landslides up to several tens of kilometres across.

A portion of the continental slope looking onshore towards Brisbane, showing the ‘eaten away’ appearance of the slope in the northern two-thirds of the image, the result of previous submarine landslides.
Samantha Clarke

What are submarine landslides?

Submarine landslides, as the name suggests, are underwater landslides where seafloor sediments or rocks move down a slope towards the deep seafloor. They are caused by a variety of different triggers, including earthquakes and volcanic activity.

The typical evolution of a submarine landslide after failure.
Geological Digressions

As we processed the incoming data to our vessel, images of the seafloor started to become clear. What we discovered was that an extensive region of the seafloor offshore New South Wales and Southern Queensland had experienced intense submarine landsliding over the past 15 million years.

From these new, high-resolution images, we were able to identify over 250 individual historic submarine landslide scars, a number of which had the potential to generate a tsunami. The Byron Slide in the image below is a good example of one of the “smaller” submarine landslides we found – at 5.6km long, 3.5km wide, 220m thick and 1.5 cubic km in volume. This is equivalent to almost 1,000 Melbourne Cricket Grounds.

This image shows the Byron Slide scar, located offshore Byron Bay.
Samantha Clarke

The historic slides we found range in size from less than 0.5 cubic km to more than 20 cubic km – the same as roughly 300 to 12,000 Melbourne Cricket Grounds. The slides travelled down slopes that were less than 6° on average (a 10% gradient), which is low in comparison to slides on land, which usually fail on slopes steeper than 11°.

We found several sites with cracks in the seafloor slope, suggesting that these regions may be unstable and ready to slide in the future. However, it is likely that these submarine landslides occur sporadically over geological timescales, which are much longer than a human lifetime. At a given site, landslides might happen once every 10,000 years, or even less frequently than this.

A collection of submarine landslide scars off Moreton Island.
Samantha Clarke

Since returning home, our investigations have focused on how, when, and why these submarine landslides occur. We found that east Australia’s submarine landslides are unexpectedly recent, at less than 25,000 years old, and relatively frequent in geological terms.

We also found that for a submarine landslide to generate along east Australia today, it is highly likely that an external trigger is needed, such as an earthquake of magnitude 7 or greater. The generation of submarine landslides is associated with earthquakes from other places in the world.

Submarine landslides can lead to tsunamis ranging from small to catastrophic. For example, the 2011 Tohoku tsunami resulted in more than 16,000 individuals dead or missing, and is suggested to be caused by the combination of an earthquake and a submarine landslide that was triggered by an earthquake. Luckily, Australia experiences few large earthquakes, compared with places such as New Zealand and Peru.

Why should we care about submarine landslides?

We are concerned about the hazard we would face if a submarine landslide were to occur in the future, so we model what would happen in likely locations. Modelling is our best prediction method and requires combining seafloor maps and sediment data in computer models to work out how likely and dangerous a landslide threat is.

Our current models of tsunamis generated by submarine landslides suggest that some sites could represent a future tsunami risk for Australia’s east coast. We are currently investigating exactly what this threat might be, but we suspect that such tsunamis pose little to no immediate threat to the coastal communities of eastern Australia.

This video shows an animation of a tsunami caused by submarine landslide.

That said, submarine landslides are an ongoing, widespread process on the east Australian continental slope, so the risk cannot be ignored (by scientists, at least).

Of course it is hard to predict exactly when, where and how these submarine landslides will happen in future. Understanding past and potential slides, as well as improving the hazard and risk evaluation posed by any resulting tsunamis, is an important and ongoing task.

The ConversationIn Australia, more than 85% of us live within 50km of the coast. Knowing what is happening far beneath the waves is a logical next step in the journey of scientific discovery.

Samantha Clarke, Associate Lecturer in Education Innovation, University of Sydney; Hannah Power, Lecturer in Coastal Science, University of Newcastle; Kaya Wilson, , University of Newcastle, and Tom Hubble, Associate professor, University of Sydney

This article was originally published on The Conversation. Read the original article.