Not just hot air: turning Sydney’s wastewater into green gas could be a climate boon



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Bernadette McCabe, University of Southern Queensland

Biomethane technology is no longer on the backburner in Australia after an announcement this week that gas from Sydney’s Malabar wastewater plant will be used to power up to 24,000 homes.

Biomethane, also known as renewable natural gas, is produced when bacteria break down organic material such as human waste.

The demonstration project is the first of its kind in Australia. But many may soon follow: New South Wales’ gas pipelines are reportedly close to more than 30,000 terajoules (TJs) of potential biogas, enough to supply 1.4 million homes.

Critics say the project will do little to dent Australia’s greenhouse emissions. But if deployed at scale, gas captured from wastewater can help decarbonise our gas grid and bolster energy supplies. The trial represents the chance to demonstrate an internationally proven technology on Australian soil.

pipeline at beach
The project would turn Sydney’s sewage into a renewable gas.
Shutterstock

What’s the project all about?

Biomethane is a clean form of biogas. Biogas is about 60% methane and 40% carbon dioxide (CO₂) and other contaminants. Turning biogas into biomethane requires technology that scrubs out the contaminants – a process called upgrading.

The resulting biomethane is 98% methane. While methane produces CO₂ when burned at the point of use, biomethane is considered “zero emissions” – it does not add to greenhouse gas emissions. This is because:

  • it captures methane produced from anaerobic digestion, in which microorganisms break down organic material. This methane would otherwise have been released to the atmosphere

  • it is used in place of fossil fuels, displacing those CO₂ emissions.

Biomethane can also produce negative emissions if the CO₂ produced from upgrading it is used in other processes, such as industry and manufacturing.

Biomethane is indistinguishable from natural gas, so can be used in existing gas infrastructure.




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The Malabar project, in southeast Sydney, is a joint venture between gas infrastructure giant Jemena and utility company Sydney Water. The A$13.8 million trial is partly funded by the federal government’s Australian Renewable Energy Agency (ARENA).

Sydney Water, which runs the Malabar wastewater plant, will install gas-purifying equipment at the site. Biogas produced from sewage sludge will be cleaned and upgraded – removing contaminants such as CO₂ – then injected into Jemena’s gas pipelines.

Sydney Water will initially supply 95TJ of biomethane a year from early 2022, equivalent to the gas demand of about 13,300 homes. Production is expected to scale up to 200TJ a year.

Two women look over the Malabar plant
The project involves cleaning and upgrading biogas from the Malabar Wastewater Treatment Plant.
Sydney Water

Biomethane: the benefits and challenges for Australia

A report by the International Energy Agency earlier this year said biogas and biomethane could cover 20% of global natural gas demand while reducing greenhouse emissions.

As well as creating zero-emissions energy from wastewater, biomethane can be produced from waste created by agriculture and food production, and from methane released at landfill sites.

The industry is a potential economic opportunity for regional areas, and would generate skilled jobs in planning, engineering, operating and maintenance of biogas and biomethane plants.

Methane emitted from organic waste at facilities such as Malabar is 28 times more potent than CO₂. So using it to replace fossil-fuel natural gas is a win for the environment.




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It’s also a win for Jemena, and all energy users. Many of Jemena’s gas customers, such as the City of Sydney, want to decarbonise their existing energy supplies. Some say they will stop using gas if renewable alternatives are not found. Jemena calculates losing these customers would lose it A$2.1 million each year by 2050, and ultimately, lead to higher costs for remaining customers.

The challenge for Australia will be the large scale roll out of biomethane. Historically, this phase has been a costly exercise for renewable technologies entering the market.

A woman cooking with gas
Biomethane will be injected into the existing gas network and delivered to homes.
Shutterstock

The global picture

Worldwide, the top biomethane-producers include Germany, the United Kingdom, Sweden, France and the United States.

The international market for biomethane is growing. Global clean energy policies, such as the European Green Deal, will help create extra demand for biomethane. The largest opportunities lie in the Asia-Pacific region, where natural gas consumption and imports have grown rapidly in recent years.

Australia is lagging behind the rest of the world on biomethane use. But more broadly, it does have a biogas sector, comprising than 240 plants associated with landfill gas power units and wastewater treatment.

In Australia, biogas is already used to produce electricity and heat. The step to grid injection is sensible, given the logistics of injecting biomethane into existing gas infrastructure works well overseas. But the industry needs government support.

Last year, a landmark report into biogas opportunities for Australia put potential production at 103 terawatt hours. This is equivalent to almost 9% of Australia’s total energy consumption, and comparable to current biogas production in Germany.

The distribution of reported operational biogas upgrading units in the IEA Bioenergy Task 37-member countries.

Current use of biogas in Australia.

A clean way to a gas-led recovery

While the scale of the Malabar project will only reduce emissions in a small way initially, the trial will bring renewable gas into the Australia’s renewable energy family. Industry group Bioenergy Australia is now working to ensure gas standards and specifications are understood, to safeguard its smooth and safe introduction into the energy mix.

The Morrison government has been spruiking a gas-led recovery from the COVID-19 recession, which it says would make energy more affordable for families and businesses and support jobs. Using greenhouse gases produced by wastewater in Australia’s biggest city is an important – and green – first step.




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The Conversation


Bernadette McCabe, Professor and Principal Scientist, University of Southern Queensland

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

One of Australia’s most famous beaches is disappearing, and storms aren’t to blame. So what’s the problem?



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Thomas Murray, Griffith University; Ana Paula da Silva, Griffith University; Darrell Strauss, Griffith University; Guilherme Vieira da Silva, Griffith University, and Rodger Tomlinson, Griffith University

Storms or tropical cyclones usually get the blame when Australia’s beaches suffer severe erosion. But on the New South Wales north coast at Byron Bay, another force is at play.

Over the past six months, tourists and locals have been shocked to see Byron’s famous Main Beach literally disappearing, inundated with water and debris. In October, lifesavers were forced to temporarily close the beach because they couldn’t get rescue equipment onto the sand. Resident Neil Holland, who has lived in the area for 47 years, told the ABC:

It’s the first time I’ve seen it this bad in all the time that I’ve been here, and it hasn’t stopped yet. The sand is just being taken away by the metre.

So what’s happening? To find the answer, we combined a brief analysis of satellite imagery with previous knowledge about the process behind the erosion and how it has been occurring at Byron Bay. The erosion is due to a process known as “headland bypassing”, and it is quite different to erosion from storms.

What is headland bypassing?

Headland bypassing occurs when sand moves from one beach to another around a solid obstruction, such as a rocky headland or cape. This process is mainly driven by wave energy. Along the coast of southeast Australia, waves generate currents that move sand mostly northward along the northern NSW coastline, and on towards Queensland.

However, sand does not flow evenly or smoothly along the coast: when sand arrives at a beach just before a rocky headland, it builds up against the rocks and the beach grows wider. When there is too much sand for the headland to hold, or there’s a change in wave conditions, some sand will be pushed around the headland – bypassing it – before continuing its journey up the coast.




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This large lump of moving sand is called a “sand pulse” or “sand slug”. The sand pulse needs the right wave conditions to move towards the shore. Without these conditions, the beach in front of the pulse is deprived of sand and the waves and currents near the shore erode the beach.

Headland bypassing was first described in the 1940s. However, only about 20 years ago was it recognised as an important part of the process controlling sand moving along the coast. Since then, with better technology and more data, researchers have studied the process in more detail, and helped to shed light on how headland bypassing might affect long-term coastal planning.

Recent studies have shown wave direction is particularly important to headland bypassing. Importantly, weather patterns that produce waves are affected by climate drivers including the El Niño Southern Oscillation and the Interdecadal Pacific Oscillation. So, future changes in the way these drivers behave will affect the waves and currents that move sand along our coast, which in turn affects headland bypassing and beach erosion.

Man sitting near eroded beach
Byron Bay’s beaches have badly eroded in recent months.
Byron Shire Council

What’s happening at Byron Bay?

In October and November this year, a large amount of sand was present just north of Cape Byron, from Wategos Beach to The Pass Beach. As this sand pulse grew, Clarkes Beach, and then Main Beach, were starved of their usual sand supply and began to erode.

The sand pulse is visible on satellite images from around April 2020. Each month, it slowly moves westward into the bay. As the sand pulse grows, the beach ahead of the pulse gradually erodes. At present Main Beach is at the eroding stage.




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Similar erosion was observed at Main Beach in the early 1990s. The beach became wider again from 1995 to 2007. From 2009 onwards, the shoreline erosion slowly began again, and became very noticeable in the past six months.

The effect of sand pulses on beach erosion is not exclusive to Byron Bay. It has been described previously in other locations, such as NSW’s Kingscliff Beach in 2011. In that case, the erosion risked damaging a nearby holiday park and bowling club.

Satellite images showing sand movement around Cape Byron
Satellite images showing sand movement around Cape Byron.
Author provided

When will this end?

Mild waves from the east to northeast, which usually occur from October to April each year, will help some of the sand pulse move onto Clarkes Beach and then further along to Main Beach. This normally happens over several months to a year. But it’s hard to say exactly when the beach will be fully restored.

This uncertainty underscores the need to better forecast these processes. This would help us to predict when bypassing sand pulses will occur and to manage beach erosion.

Climate change is expected to affect wave conditions, although the exact impact on the headland bypassing process remains unclear. However, better predictions would allow the community to be informed early about expected impacts, and officials could better manage and plan for future erosion.

Meanwhile, Byron Bay waits and watches – knowing at least that the erosion problem will eventually improve.The Conversation

People walking along Main Beach
The sand at Main Beach at Byron Bay, pictured here under good conditions, will eventually return.
AAP

Thomas Murray, Research Fellow (Coastal Management), Griffith University; Ana Paula da Silva, PhD Candidate, Griffith University; Darrell Strauss, Senior Research Fellow, Griffith University; Guilherme Vieira da Silva, Research Fellow, Griffith University, and Rodger Tomlinson, Director – Griffith Centre for Coastal Management, Griffith University

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

NSW has joined China, South Korea and Japan as climate leaders. Now it’s time for the rest of Australia to follow



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Tim Nelson, Griffith University and Joel Gilmore, Griffith University

It’s been a busy couple of months in global energy and climate policy. Australia’s largest trading partners – China, South Korea and Japan – have all announced they will reach net-zero emissions by about mid-century. In the United States, the incoming Biden administration has committed to decarbonising its electricity system by 2035.

These pledges have big implications for Australia. With some of the best renewable resources in the world, we have much to gain from the transition. And this week, the New South Wales government embraced the opportunity.

Its new A$32 billion Electricity Infrastructure Roadmap will, among other things, support the construction of 12 gigawatts of new renewable energy capacity by 2030. This is six times the capacity of the state’s Liddell coal-fired power station, set to close in 2023.

The roadmap was developed by NSW Environment Minister Matt Kean through extensive consultation with industry and others, including ourselves. While we believe a national carbon price is the best way to reduce emissions, the NSW approach nonetheless sets an example for other states looking to increase renewable energy capacity. So let’s take a closer look at the plan.

NSW Environment Minister Matt Kean
The authors worked with NSW Environment Minister Matt Kean, pictured, to help devise the policy.
Dean Lewins/AAP

What’s the roadmap all about?

The roadmap acknowledges that within 15 years, three-quarters of NSW’s coal-fired electricity supply is expected to reach the end of its technical life. It says action is needed now to ensure cheap, clean and reliable electricity, and to set up NSW as a global energy superpower.

The plan involves a coordinated approach to transmission, generation and storage. By 2030, the government aims to:

  • deliver about 12 gigawatts of new transmission capacity through so-called “renewable energy zones” in three regional areas by 2030. It would most likely be generated by wind and solar

  • support about 3 gigawatts of energy storage to help back up variable renewable energy supplies. This would involve batteries, pumped hydro, and “hydrogen ready” gas peaking power stations

  • attract up to A$32 billion in private investment in regional energy infrastructure investment by 2030

  • support more than 6,300 construction and 2,800 ongoing jobs in 2030, mostly in regional NSW

  • reduce NSW’s carbon emissions by 90 million tonnes.

The plan also aims to see the average NSW household save about A$130 a year in electricity costs, although this might be hard to achieve in practice. And regional landholders hosting renewable projects on their properties are expected to earn A$1.5 billion in revenue over the next 20 years.

The Liddell coal-fired power station
12 gigawatts of new renewables capacity is about six times the capacity of NSW’s Liddell coal-fired power station.
Shutterstock

Giving generators options

One of the most innovative aspects of the NSW proposal is that generators will have two options when it comes to selling their electricity.

First, the government will appoint an independent “consumer trustee” to purchase electricity from generators at an agreed price – giving the generators the long-term certainty they need to invest. The trustee would then sell this electricity either directly to the market, or through contracts to retailers.

But the trustee will encourage generators to first seek a better price by finding their own customers, such as energy consumers and other electricity retailers.




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This system is different to the approach adopted in Victoria and the ACT, where government contracts remove any incentive for generators to participate in the energy market. Over time, this limits market competition and innovation.

The NSW plan improves on existing state policies in another way – by aligning financial incentives to the physical needs of the system. The Consumer Trustee will enter into contracts with projects that produce electricity at times of the day when consumers need it, and not when the system is already oversupplied.

While this won’t be easy for the trustee to model, this approach is likely to benefit consumers more than in other jurisdictions where lowest-cost projects seem to be preferred, irrespective of whether the energy they produced is needed by consumers.

One shortcoming of the roadmap is it does not financially reward existing low-emissions electricity generators in NSW, nor does it charge carbon-heavy electricity producers for the emissions they produce. This could be corrected in the future by integrating the policy into a nationally consistent carbon price, which transfers the cost of carbon pollution onto heavy emitters.

A $50 note sticking out of a power socket
Electricity generators will be guaranteed a floor price for their electricity.
Julian Smith/AAP

Why is all this so important?

NSW’s ageing coal-fired power stations are chugging along – albeit with ever-declining reliability. But it’s only a matter of time before something expensive needs fixing. This was the case with Hazelwood in Victoria: the old walls of the boilers had thinned to less than 2 millimetres. The repair cost was prohibitive and the station closed with just five months’ notice. Electricity prices shot up in response to unexpectedly reduced supply.

In NSW, the consumer trustee will be tasked with helping ensuring replacement generation is delivered in a timely way. This means developing new generation capacity well ahead of announced coal plant closures.

This is a helpful development. But ultimately a stronger measure will be needed to ensure coal plants give early notice of their intention to exit the market. The Grattan Institute has previously suggested coal generators put up bonds that are forfeited if they close early. We think this model is worth considering again.

Seize the opportunity

As the world’s largest exporter of coal and LNG, Australia has much to lose as global economies shift to zero emissions. But our renewable energy potential means we also have much to gain.

Australia needs a durable, nationally consistent policy framework if we’re to seize the opportunities of the global transition to clean energy. The NSW roadmap is a significant step in the right direction.




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The Conversation


Tim Nelson, Associate Professor of Economics, Griffith University and Joel Gilmore, Associate Professor, Griffith University

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

We looked at 35 years of rainfall and learnt how droughts start in the Murray-Darling Basin


Chiara Holgate, Australian National University; Albert Van Dijk, Australian National University, and Jason Evans, UNSW

The extreme, recent drought has devastated many communities around the Murray-Darling Basin, but the processes driving drought are still not well understood.

Our new study helps to change this. We threw a weather model into reverse and ran it back for 35 years to study the natural processes leading to low rainfall during drought.




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And we found the leading cause for drought in the Murray-Darling Basin was that moisture from oceans didn’t reach the basin as often as normal, and produced less rain when it did. In fact, when moisture from the ocean did reach the basin during drought, the parched land surface actually made it harder for the moisture to fall as rain, worsening the already dry conditions.

These findings can help resolve why climate models struggle to simulate drought well, and ultimately help improve our ability to predict drought. This is crucial for our communities, farmers and bushfire emergency services.

There’s still a lot to learn about rain

The most recent drought was relentless. It saw the lowest rainfall on record in the Murray-Darling Basin, reduced agricultural output, led to increased food prices, and created tinder dry conditions before the Black Summer fires.

Drought in the Murray-Darling Basin is associated with global climate phenomena that drive changes in ocean and atmospheric circulation. These climate drivers include the El Niño and La Niña cycle, the Indian Ocean Dipole and the Southern Annular Mode.

Each influences the probability of rainfall over Australia. But drivers like El Niño can only explain around 20% of Australian rainfall — they only tell part of the story.




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To fully understand the physical processes causing droughts to begin, persist and end, we need to answer the question: where does Australia’s rainfall come from? It may seem basic, but the answer isn’t so simple.

Where does Australia’s rainfall come from?

Broadly, scientists know rainfall derives from evaporation from two main sources: the ocean and the land. But we don’t know exactly where the moisture supplying Australia’s rainfall originally evaporates from, how the moisture supply changes between the seasons nor how it might have changed in the past.

To find out, we used a sophisticated model of Australia’s climate that gave data on atmospheric pressure, temperature, humidity, winds, rainfall and evaporation.




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We put this data into a “back-trajectory model”. This traced the path of water from where it fell as rain, backwards in time through the atmosphere, to uncover where the water originally evaporated from. We did this for every day it rained over Australia between 1979 and 2013.

Not surprisingly, we found more than three-quarters of rain falling in Australia comes from evaporation from the surrounding oceans. So what does this mean for the Murray-Darling Basin?

Up to 18% of rain in the basin starts from the land

During the Millennium Drought and other big drought years (such as in 1982), the Murray-Darling Basin heavily relied on moisture transported from the Tasman and Coral seas for rain. Moisture evaporated off the east coast needs easterly winds to transport it over the Great Dividing Range and into the Murray-Darling Basin, where it can form rain.

This means low rainfall during these droughts was a result of anomalies in atmospheric circulation, which prevented the easterly flow of ocean moisture. The droughts broke when moisture could once again be transported into the basin.

A lack of vegetation on the land can exacerbate drought.
Shutterstock

The Murray-Darling Basin was also one of the regions in Australia where most “rainfall recycling” happens. This is when, following rainfall, high levels of evaporation from soils and plants return to the atmosphere, sometimes leading to more rain – particularly in spring and summer.

This means if we change the way we use the land or the vegetation, there is a risk we could impact rainfall. For example, when a forest of tall trees is replaced with short grass or crops, humidity can go down and wind patterns change in the atmosphere above. Both of these affect the likelihood of rain.




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In the northern part of the basin, less evaporation from the dry land surface exacerbated the low rainfall.

On the other hand, when the drought broke, more moisture evaporated from the damp land surface, adding to the already high levels of moisture coming from the ocean. This meant the region got a surplus of moisture, promoting even more rain.

This relationship was weaker in the southern part of the basin. But interestingly, rainfall there relied on moisture originating from evaporation in the northern basin, particularly during drought breaks. This is a result we need to explore further.

Summer rain not so good for farmers

Rainfall and moisture sources for Australia and the Murray-Darling Basin are changing. In the past 35 years, the southeast of the country has been receiving less moisture in winter, and more in summer.

This is likely due to increased easterly wind flows of moisture from the Tasman Sea in summer, and reduced westerly flows of moisture from the Southern Ocean in winter.

This has important implications, particularly for agriculture and water resource management.

For example, more rainfall in summer can be a problem for horticultural farms, as it can make crops more susceptible to fungal diseases, decreases the quality of wine grape crops and affects harvest scheduling.

Less winter rain also means less runoff into creeks and rivers — a vital process for mitigating drought risk. And this creates uncertainty for dam operators and water resource managers.




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Understanding where our rainfall comes from matters, because it can improve weather forecasts, seasonal streamflow forecasts and long-term rainfall impacts of climate change. For a drought-prone country like Australia — set to worsen under a changing climate — this is more crucial than ever.The Conversation

Chiara Holgate, Hydrologist & PhD Candidate, Australian National University; Albert Van Dijk, Professor, Water and Landscape Dynamics, Fenner School of Environment & Society, Australian National University, and Jason Evans, Professor, UNSW

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

Environment Minister Sussan Ley faces a critical test: will she let a mine destroy koala breeding grounds?


Lachlan G. Howell, University of Newcastle and Ryan R. Witt, University of Newcastle

In the next few weeks, federal Environment Minister Sussan Ley will decide whether to approve a New South Wales quarry expansion that will destroy critical koala breeding grounds.

The case, involving the Brandy Hill Quarry at Port Stephens, is emblematic of how NSW environment laws are failing wildlife — particularly koalas. Efforts to erode koala protections hit the headlines last week when NSW Nationals leader John Barilaro threatened to detonate the Coalition over the issue.




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Koala populations are already under huge pressure. A NSW parliamentary inquiry in June warned the koala faces extinction in the state by 2050 if the government doesn’t better control land clearing and habitat loss.

Ley could either continue these alarming trends, or set a welcome precedent for koala protection. Her decision is also the first big test of federal environment laws since an interim review found they were failing wildlife. So let’s take a closer look at what’s at stake in this latest controversy.

A koala clinging to a tree branch
This female koala is under threat from the Brandy Hill Quarry expansion.
Lachlan Howell, Author provided

The Brandy Hill Quarry expansion

The NSW government gave approval to Hanson Construction Materials, a subsidiary of Heidelberg Cement, to expand the existing Brandy Hill Quarry in Seaham in Port Stephens.

The project would provide concrete to meet Sydney’s growing construction demands, as the state fast-tracks infrastructure projects to help the economy recover from COVID-19.

The approval came despite the known presence of koalas in the area. A koala survey report, completed on behalf of the developer in 2019, determined the project would “result in a significant impact to the koala”.

The report recommended the quarry expansion be referred to the federal Environment Minister under the Environment Protection and Biodiversity Conservation (EPBC) Act 1999, for its potential impacts on “Matters of National Environmental Significance”.




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The expansion site intersects habitat with preferred high quality koala feed and shelter trees. This habitat is established forest containing various key mature Eucalyptus trees, including the forest red gum and swamp mahogany.

The survey report didn’t propose any mitigation strategies to sustain the habitat. Instead, it suggested minimisation measures, such as ecologists to be present during habitat clearing, low speed limits for vehicles on site, and education on koalas for workers.

A disaster for koalas

In support of a community grassroots campaign (Save Port Stephens Koalas), we produced an report on the effect of the quarry expansion on koalas. The report now sits with Ley ahead of her decision, which is due by October 13.

Male koalas will bellow during the breeding season to attract females.

The expansion will clear more than 50 hectares of koala habitat. We found koalas breeding within 1 kilometre of the current quarry boundary, which indicates the expansion site is likely to destroy critical koala breeding habitat.

During the breeding season, male koalas bellow to attract females. Within 1km of the boundary we observed a female koala and a bellowing male koala 96m apart. A second male was reported bellowing 227m from the quarry boundary.

What’s more, the site expansion occurs within a NSW government listed Area of Regional Koala Significance. The expansion site actually has higher average koala habitat suitability than all remaining habitat on the quarry property.

The Koala Habitat Suitability Model from our independent report. The red boundary represents the Quarry expansion site containing high habitat suitability.
Map produced by S. A. Ryan using the Koala Habitat Information Base and arcGIS 10.6., Author provided

CSIRO research from 2016 suggests koalas in Port Stephens can move hundreds of metres in a day and up to 5km in one month. Movement is highest during the breeding season. This potential for koalas to move away was a key reason the NSW government approved the expansion.

Koalas can move in to the remaining property to breed, or they can move away from it. But habitat outside the expansion site is, on average, lesser quality, and this is where the expansion would force the koalas to move to.




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This habitat fragmentation would not only result in lost access to potential breeding grounds, but also further restrict movement and expose koalas to threats such as predation or road traffic.

Lastly, the expansion would sever a crucial East–West corridor koalas likely use to move across the landscape and breed.

Approved under the state’s weak environmental protections

It may seem surprising this destructive project was approved by the NSW government. But it’s a common story under the state’s protections.

Alarm over the weaknesses of NSW environmental protections has been raised by NSW government agencies including the Natural Resources Commission and NSW Audit Office.




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The expansion approval is an example of how the NSW government relaxed the regulatory requirements for land clearing between 2016 and 2017. This led to a 13-fold increase in land clearing approvals, and tipped the balance away from sustainable development.

Female and male koalas spotted 1 km from the quarry boundary. The male was observed bellowing 96 m from the female koala. Photo: Lachlan Howell.

The expansion shines another spotlight on NSW’s poor biodiversity offset laws.

Biodiversity offsets involve compensating for environmental damage in one location by improving the environment elsewhere. Under the expansions approval, the developer was required to protect an estimated 450 hectares of habitat as offset.

But the recent parliamentary inquiry into NSW koalas recommended offsetting of prime koala habitat — such as that involved in the quarry expansion — be prohibited, which would mean not destroying the habitat in the first place.




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The NSW decision also does not account for the Black Summer Bushfires which claimed 5,000 koalas and burned millions of hectares of koala habitat. The Port Stephens population was unburned but more than 75% of its habitat has been lost since colonial occupation. Securing this population is important for the overall security of koalas in the state.

The koalas are in Sussan Ley’s hands

Sussan Ley will now assess the expansion under the EPBC Act. A recent interim report into the laws said they’d allowed an “unsustainable state of decline” of Australia’s environment.

Rejections under these laws are rare; just 22 of 6,500 projects referred for approval under the act have been refused. However, it’s not impossible.

Earlier this year Ley rejected a wind-farm in Queensland which threatened unburned koala habitat. If Ley gives full consideration to the evidence in our report, she should make the same decision.




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The Conversation


Lachlan G. Howell, PhD Candidate | School of Environmental and Life Sciences, University of Newcastle and Ryan R. Witt, Conjoint Lecturer | School of Environmental and Life Sciences, University of Newcastle

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

Recovering water for the environment in the Murray-Darling: farm upgrades increase water prices more than buybacks



Murray Darling Junction, Wentworth NSW.
Hypervision Creative/Shutterstock

Neal Hughes, Australian Bureau of Agricultural and Resource Economics and Sciences (ABARES); David Galeano, Australian Bureau of Agricultural and Resource Economics and Sciences (ABARES), and Steve Hatfield-Dodds, Australian Bureau of Agricultural and Resource Economics and Sciences (ABARES)

It’s been 13 years since the Australian Government set out to develop the Murray-Darling Basin Plan with the goal of finding a more sustainable balance between irrigation and the environment.

Like much of the history of water sharing in the Murray-Darling over the last 150 years, the process has been far from smooth. However, significant progress has been achieved, with about 20% of water rights recovered from agricultural users and redirected towards environmental flows.

One of the most difficult debates has been over how the water should be recovered.

Initially most occurred via “buybacks” of water rights from farmers. While relatively fast and inexpensive, opposition to buybacks emerged due to concerns about their effects on water prices and irrigation farmers and regional communities.

This led to a new emphasis on infrastructure programs including farm upgrades in which farmers received funding to improve their irrigation systems in return for surrendering water rights.

While these farm upgrades are more expensive, it was thought that they would have fewer negative effects on farmers and communities.

However, new research from the Australian Bureau of Agricultural and Resource Economics and Sciences finds that – while beneficial for their participants – these programs push water prices higher, placing pressure on the wider irrigation sector.

Two types of water recovery programs

The Murray-Darling Basin operates under a “cap and trade” system. Each year there is a limit on how much water can be extracted from the basin’s rivers, based on the available supply.

Water users (mostly farmers) hold rights to a share of this limit, and they can trade these rights on a market.

To date 1,230 gigalitres of these water rights have been bought from farmers via buyback programs at a cost of about A$2.6 billion.




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The other type of program is farm upgrades which offer farmers funding to improve their irrigation infrastructure in return for a portion of their water rights.

To date 255 gigalitres of water has been recovered through farm upgrades at a cost of about $1 billion.


Annual volume of water rights recovered for the environment since 2007-08

For infrastructure projects the financial year refers to the contract date. The actual transfer of entitlements may occur in a later financial year. The volume of water recovered is expressed in terms of the long-term average annual yield. The estimates do not include water recovered through state projects (160 gigalitres) or water gifted to the Commonwealth (15 gigalitres). Off-farm infrastructure includes water recovered through projects that are a combination of on-farm, off-farm and land purchases.
Sources: Department of Agriculture Water and Environment, Commonwealth Environmental Water Holder

Water recovery has increased prices

As would be expected, the dominant short-term driver of prices is water availability, with large price increases during droughts. The dominant longer-term drivers include lower average rainfall related to climate change and the emergence of new irrigation crops including almonds.

While water recovery has played less of a role, buybacks and farm upgrades have still reduced the supply of water to farmers and increased prices to some extent.




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Our modelling suggests water prices in the southern basin are around $72 per megalitre higher on average as a result of water recovery measures, with the effects varying year-to-year depending on conditions.


Modelled water allocation prices with and without water recovery

Price refers to volume weighted average annual water allocation prices across the southern Murray Darling Basin. Water recovery reflects the cumulative volume of buybacks and farm upgrades at each year. Water recovery began in 2007-08.
ABARES modelling

Farm upgrades increase prices more than buybacks

Farm upgrades are often viewed as an opportunity to save water and produce “more crop per drop”.

But they can also encourage farmers to increase their water use as they seek to make the most of their new infrastructure: sometimes referred to as a “rebound effect”.

While there have been concerns about rebound effects for some time, there has been limited evidence until recently.

Less-wasteful irrigation can save water, as long as there’s no ‘rebound’

As would be expected, our study finds that upgraded farms have benefited in terms of profits and productivity. However, we also find large rebound effects, with upgraded farms increasing their water use by between 10% and 50%.

To get the extra water they need to buy it from other farmers, putting pressure on prices. We find the resulting price impact to be much more than the impact of buying back water. Per unit of water recovered, it is about double that of buybacks.

These higher water prices increase the risk that irrigation assets – including some newly upgraded systems – could become stranded as price sensitive irrigation activities become less profitable.

No easy answers

Recovering water through off-farm infrastructure is one alternative, however the most effective projects have already been developed, leaving cost-effective water saving schemes harder to find.

This brings us back to buybacks. Because buybacks are cheaper than farm infrastructure programs, there is more scope to combine them with regional development investments to help offset negative impacts on communities.

The challenge is that in a connected water market the flow-on effects on water prices and farmers can be complex and difficult to predict, making it hard to know where to direct development investments.




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Billions spent on Murray-Darling water infrastructure: here’s the result


A potential middle ground is rationalisation, where parts of the water supply network are decommissioned, and affected farmers are compensated both for their water rights and for being disconnected from water supply. This approach has less effect on water prices and allows regional development initiatives to be targeted to the affected areas.

However, rationalisation can be hard to implement given it requires negotiating with all affected farmers and all levels of government.

Given the complexity of the Murray-Darling Basin, water policy is far from simple. While it is clear more water will be needed to put the basin on a sustainable footing, there are no easy options.

Further progress will require careful policy design to help ease adjustment pressure on farmers and regional communities.The Conversation

Neal Hughes, Senior Economist, Australian Bureau of Agricultural and Resource Economics and Sciences (ABARES); David Galeano, Assistant Secretary, Natural Resources, Australian Bureau of Agricultural and Resource Economics and Sciences (ABARES), and Steve Hatfield-Dodds, Executive Director, Australian Bureau of Agricultural and Resource Economics and Sciences (ABARES)

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

A contentious NSW gas project is weeks away from approval. Here are 3 reasons it should be rejected



Ursula Da Silva/AAP

Madeline Taylor, University of Sydney and Susan M Park, University of Sydney

New South Wales planning authorities relied on flawed evidence when backing a highly controversial coal seam gas project that may endanger critical water supplies, farmland and threatened species, our analysis has found.

Early next month, the Independent Planning Commission NSW (IPC) is due to announce its decision on the future of the A$3.6 billion Narrabri Gas Project. The commission will presumably give substantial weight to an assessment report by the NSW Department of Planning, Industry and Environment (DPIE), which recommended the proposal be approved.

However, we contend DPIE has failed to substantiate its claims that the Narrabri Gas Project:

  • will improve gas security for NSW
  • does not pose a significant risk to important water resources
  • will not cause significant impacts to people or the environment.

Some 23,000 submissions were made on the Narrabri Gas Project, 98% of which opposed it. They include Australia’s former chief scientist Penny Sackett, who says the project is at odds with the nation’s Paris climate commitments.

The pending decision comes at a critical time for Australia’s gas industry. The Morrison government has flagged a gas-led economic recovery from COVID-19, and on Monday there were reports the October federal budget will contain support for the industry.

The experience of the Narrabri Gas Project so far shows government decisions on such proposals must be evidence-based and take full account of risks to the environment, people and the economy.

People protesting the gas project.
Community opposition to the Narrabri Gas Project is strong.
Paul Miller/AAP

What is the Narrabri Gas Project?

The Narrabri Gas Project aims to produce “unconventional” or coal seam gas, by sinking 850 wells in the Pilliga region near Narrabri in northwest NSW.

State authorities have spent four years assessing the project, and a decision by the IPC is due by September 4.




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Some 60% of the project is located in the Pilliga forest – the largest forest and woodlands in western NSW and home to threatened species including the koala. The remaining 40% of the project is next to prime farmland. It is also located on the traditional lands of the Gomeroi people.

As assessment by DPIE recommended the proposal be approved. We believe the evidence upon which the department based its decision was flawed. Here are three big problems we identified:

1. Gas security

DPIE says the Narrabri Gas Project is in the public interest because it will contribute to gas security for NSW. This assertion is based on a scenario in which Santos commits to providing all gas from the project solely to NSW, rather than the wider East Coast Gas Market.

Yet, DPIE’s recommended conditions for approval make no mention of Santos promising, or being legally compelled, to reserve gas for NSW consumers if the project is approved.

A woman stands in front of a gas burner.
Gas industry supporters say its expansion will shore up energy supplies.
Carlos Barria/Reuters

2. Water risks

The assessment fails to provide evidence showing the project does not pose significant risk to high-quality groundwater in a region and ecosystem highly dependent on it.

The project will drill extensively below the Great Artesian Basin, potentially contaminating groundwater, land and surface water. Despite Santos and the department’s assumptions that risks will be minimal, recent research shows methane contamination of groundwater occurs due to changes in pressures during water and gas extraction.

This risks human health and safety, and compromises water quality. Wastewater has already leaked in the proposed project area during pilot exploration and production, demonstrating the high risks involved.




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Scott Morrison’s gas transition plan is a dangerous road to nowhere


The department’s assessment of threats to the water table and management of waste brine is not robust. For example, the government’s own independent Water Expert Panel recommends brine be disposed of at landfill facilities. But brine and salt generated by the project would be highly soluble in comparison to standard landfill waste, and require robust storage management to prevent leaching and migration, according to our colleague and co-author of our assessment, Matthew Currell.

The department’s recommendation of an “adaptive management” approach – essentially “learning by doing” – is risky, given the highly complex potential impacts which are almost impossible to guard against.

Forest at the site of the proposed project
Forest at the site of the proposed project is home to threatened species.
Dean Lewins/AAP

3. Effect on people

DPIE’s assessment does not provide robust evidence that people will not be significantly harmed by the project.

Santos commissioned a social impact assessment, and the department engaged University of Queensland professor Deanna Kemp to review it. DPIE took the view that this review constitutes support for the project and states “overall, the negative social impacts of the project can be appropriately managed”.

However in correspondence with our colleague and co-author of our assessment Rebecca Lawrence, Professor Kemp expressed concern the department “misconstrued” her advice and misinterpreted it as giving the project a “green light”. Professor Kemp stated that her advice in no way constitutes a recommendation of approval of the project.




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We believe Professor Kemp was not commissioned by DPIE to comprehensively assess the social impact merits of the project, nor did she do so.

In a response to The Conversation, Professor Kemp said she did not contest the claims made by the authors of this article, and said “any suggestion that my review constitutes an approval of the project would be incorrect”.

There is sufficient evidence to suggest the social impacts in the short and long term will be unmanageable. These include social conflicts over the proposed gas project, loss of rural livelihoods from contamination of both groundwater and surface water, and effects on Aboriginal people and the broader Narrabri community – which is already socially disadvantaged and vulnerable.

Officials inspect the Narrabri Gas Project
Officials inspect the Narrabri Gas Project in the Pilliga region of NSW.
Dean Lewins/AAP

A big decision

The Narrabri Gas Project presents considerable and significantly underestimated risks to the environment, sensitive water resources and communities.

The department’s argument that Narrabri gas will increase NSW’s energy security is highly unlikely and at present there’s nothing to suggest such a condition would be legally enforced. And its assertion the project would not harm people or the environment is not backed by evidence.

On this basis, we believe the Narrabri Gas Project is unsustainable, unviable and not in the public interest.


In response to this article, the NSW Department of Planning, Industry and Environment said in a statement it “does not agree with any of these claims”, adding:

The Department’s comprehensive assessment of the proposal was informed by extensive community consultation, advice from the Narrabri Shire Council, government agencies and independent experts, including a Water Expert Panel,“ it said.

The assessment concluded that the project is critical for energy security and reliability in NSW, would deliver significant economic benefits to NSW and the Narrabri region, and has been designed to minimise environmental impacts.

Santos has made a commitment that the gas would be provided only to the domestic gas market and has agreed to accept a condition to this effect on any petroleum production lease granted for the project.

The Department’s assessment found the project is in the public interest and is approvable, subject to strict conditions.

Comment has been sought from Santos.The Conversation

Madeline Taylor, Lecturer, University of Sydney and Susan M Park, Associate Professor of International Relations, University of Sydney

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

‘It is not easy’: how science and courage saved the stunning Australian Alps



National Library of Australia

Philip Gibbons, Australian National University

Most people probably associate the Australian Alps with skiing and snow. Others might think of the Man from Snowy River legend or the engineering feats of the Snowy Hydro-Electric Scheme.

But few people know the region’s history of exploitation and overuse, nor the courage of those who fought to save this precious wilderness area. A new book, Kosciuszko: A Great National Park, tells that important story. The result, by authors Deirdre Slattery and Graeme L. Worboys, is a positive yet cautionary tale.

Today, the park is largely protected – yet threats such as ski tourism, feral horses and the Snowy 2.0 scheme still loom. And climate change has left the region highly vulnerable, as shown by declining snow depths and a massive bushfire that tore through the Snowy Mountains last summer.

The book shows how Kosciuszko National Park is the product of robust science and hard-fought battles by dedicated individuals – battles that continue to this day.

A ranger-guided tour leaving for the Kosciuszko summit in 1964.
A ranger-guided tour leaving for the Kosciuszko summit in 1964.
Gare collection in Kosciuszko: A Great National Park

A long history of occupation

The Australian Alps in southeast New South Wales is the traditional home of three Aboriginal groups: the Ngarigo, Walgalu and Djilamatang people. It is home to Australia’s highest peak, Mount Kosciuszko.

The book describes how squatters with cattle occupied the region from the 1820s. By 1840, the Snowy region had been stocked with 200,000 sheep, 75,000 cattle and 3,000 horses which grazed in the mountains each summer.




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The discovery of gold in 1860 brought another 10,000 people to the Snowy Mountains. By the turn of the 20th century, the mountains were also a playground for recreation. Hotel Kosciusko, with 93 bedrooms, a ballroom, museum, skating rink and tennis courts, catered for an upmarket clientele.

In 1949 the mountains became the site for the Snowy Mountains Hydro-Electric Scheme: 16 dams, 80 kilometres of aqueducts and more than 140 kilometres of tunnels.

By then, the signs of overuse were evident. Soils were eroding, streams became silted and unique alpine flora was diminishing.

Cattle grazing at Club Lake believed to be during the Federation Drought (1897-1903).
Cattle grazing at Club Lake believed to be during the Federation Drought (1897-1903).
Kerry Studio/Costin collection in Kosciuszko: A Great National Park.

The long conservation fight

Tannat William Edgeworth David, a professor at the University of Sydney, was one of the first to document the unique values of the Snowy Mountains and call for their protection.

In the 1800s, the notion that an ice age once gripped Australia was considered preposterous. The book tells how David and colleagues put the matter “absolutely beyond dispute” when they mapped, on Kosciuszko’s main range, the undeniable signature left by glaciers.

In the early 1900s, David urged that the alpine area be preserved:

[I]t would be wise policy, in the interest of people and of science, to reserve from occupation and even from the depasturing of stock, all the highest points of our alpine plateau, so that this floral wonderland may be preserved intact for posterity…

It took almost 50 years before this advice was heeded. Kosciuszko State Park — later Kosciuszko National Park – was proclaimed in 1944. A decade of further scientific research led to the end of summer grazing leases above 1,350 metres in 1958.

One of the first park managers was Neville Gare. As the book notes, Gare quickly learned that feelings over management of the mountains ran deep. Soon after rangers started impounding stock found illegally in the park, an effigy of a park ranger swinging from a hangman’s noose was installed on the veranda of the Jindabyne Hotel.




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In 1950, Gare resisted a plan by head of the Ski Tourers Association, Charles Anton, to build a network of ski lodges. The book recounts how the tensions culminated at a public function when Anton snipped Gare’s tie in half to “indicate his indifference to Gare’s authority”. Some lodges were later built.

In his unpublished memoir, Gare wrote “it is not easy to conserve something and use it too”. In future years, this observation would prove all too true.

Stock illegally moved into the park after grazing leases ended in 1958.
Stock illegally moved into the park after grazing leases ended in 1958.
Alec Costin in Kosciuszko: A Great National Park

Ongoing battles

Gare and the Kosciusko State Park Trust developed the first formal plan of management for the park in 1965. The park was divided into zones for different uses: wilderness, conservation of exceptional natural and historic features, development, hydro-electricity and tourism.

This zoning was radical thinking at the time but has since been widely adopted in park management across Australia.

The plan of management for Kosciuszko National Park has been frequently amended to accommodate more tourism facilities, and the threat of further development is ever-present. As the authors note, further pressure is also coming via Snowy 2.0, a A$5 billion proposal to expand the current hydroelectric scheme.

Climate change is also a threat. Rising temperatures have triggered a 15% decline in the annual maximum snow depth, relative to the 1961-90 average.

Skiers at Perisher Valley
Climate change is reducing the snow depth in the region.
Perisher/AAP

Climate change is also making the threat of bushfires worse. In January, the massive Adaminaby Complex fire burned through more than 93,000 hectares in the Snowy region, affecting swathes of bush. It also devastated populations of several threatened species, including the corroboree frog and the stocky galaxias fish.

And the lethal chytrid fungus, introduced to Australia, has pushed the park’s southern corroboree frog to the brink of extinction.




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In 2018, the NSW government declared feral horses in the park a protected species. The population has quickly grown to about 19,000, representing a considerable threat to several species.

The book reminds us that today, as throughout history, Kosciuszko National Park needs protecting. And key to that are courageous, committed individuals – and robust science.The Conversation

A scenic view of the Snowy Mountains
The Snowy Mountains are protected, but threats remain.
Schopier/Wikimedia

Philip Gibbons, Professor, Australian National University

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

Unwelcome sea change: new research finds coastal flooding may cost up to 20% of global economy by 2100



Darren Pateman/AAP

Ebru Kirezci, University of Melbourne and Ian Young, University of Melbourne

Over the past two weeks, storms pummelling the New South Wales coast have left beachfront homes at Wamberal on the verge of collapse. It’s stark proof of the risks climate change and sea level rise pose to coastal areas.

Our new research published today puts a potential price on the future destruction. Coastal land affected by flooding – including high tides and extreme seas – could increase by 48% by 2100. Exposed human population and assets are also estimated to increase by about half in that time.

Under a scenario of high greenhouse gas emissions and no flood defences, the cost of asset damage could equate up to 20% of the global economy in 2100.

Without a dramatic reduction in greenhouse gas emissions, or a huge investment in sea walls and other structures, it’s clear coastal erosion will devastate the global economy and much of the world’s population.

In Australia, we predict the areas to be worst-affected by flooding are concentrated in the north and northeast of the continent, including around Darwin and Townsville.

Man cleans up after Townsville flood
A clean-up after flooding last year in Townsville, an Australian city highly exposed to future sea level rise.
Dan Peled/AAP

Our exposed coasts

Sea levels are rising at an increasing rate for two main reasons. As global temperatures increase, glaciers and ice sheets melt. At the same time, the oceans absorb heat from the atmosphere, causing the water to expand. Seas are rising by about 3-4 millimetres a year and the rate is expected to accelerate.

These higher sea levels, combined with potentially more extreme weather under climate change, will bring damaging flooding to coasts. Our study set out to determine the extent of flooding, how many people this would affect and the economic damage caused.




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We combined data on global sea levels during extreme storms with projections of sea level rises under moderate and high-end greenhouse gas emission scenarios. We used the data to model extreme sea levels that may occur by 2100.

We combined this model with topographic data (showing the shape and features of the land surface) to identify areas at risk of coastal flooding. We then estimated the population and assets at risk from flooding, using data on global population distribution and gross domestic product in affected areas.

Homes at Collaroy in Sydney damaged by storm surge
Many coastal homes, such as these at Sydney’s Collaroy beach, are exposed to storm surge damage.
David Moir/AAP

Alarming findings

So what did we find? One outstanding result is that due to sea level rise, what is now considered a once-a-century extreme sea level event could occur as frequently as every ten years or less for most coastal locations.

Under a scenario of high greenhouse gas emissions and assuming no flood defences, such as sea walls, we estimate that the land area affected by coastal flooding could increase by 48% by 2100.




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This could mean by 2100, the global population exposed to coastal flooding could be up to 287 million (4.1% of the world’s population).

Under the same scenario, coastal assets such as buildings, roads and other infrastructure worth up to US$14.2 trillion (A$19.82 trillion) could be threatened by flooding.

This equates to 20% of global gross domestic product (GDP) in 2100. However this worst-case scenario assumes no flood defences are in place globally. This is unlikely, as sea walls and other structures have already been built in some coastal locations.

In Australia, areas where coastal flooding might be extensive include the Northern Territory, and the northern coasts of Queensland and Western Australia.

Elsewhere, extensive coastal flooding is also projected in:
– southeast China
– Bangladesh, and India’s states of West Bengal and Gujurat
– US states of North Carolina, Virginia and Maryland
– northwest Europe including the UK, northern France and northern Germany.

A woman struggles through floodwaters in Bangladesh
Bangladesh is among the nations most exposed to coastal flooding this century.
SOPA

Keeping the sea at bay

Our large-scale global analysis has some limitations, and our results at specific locations might differ from local findings. But we believe our analysis provides a basis for more detailed investigations of climate change impacts at the most vulnerable coastal locations.

It’s clear the world must ramp up measures to adapt to coastal flooding and offset associated social and economic impacts.

This adaptation will include building and enhancing coastal protection structures such as dykes or sea walls. It will also include coastal retreat – allowing low-lying coastal areas to flood, and moving human development inland to safer ground. It will also require deploying coastal warning systems and increasing flooding preparedness of coastal communities. This will require careful long-term planning.

All this might seem challenging – and it is. But done correctly, coastal adaptation can protect hundreds of millions of people and save the global economy billions of dollars this century.




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The Conversation


Ebru Kirezci, PhD candidate, University of Melbourne and Ian Young, Kernot Professor of Engineering, University of Melbourne

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