No Australian city has a long-term vision for living sustainably. We can’t go on like this


Mike Berry, RMIT University and Ian Lowe, Griffith University

This article is part of a series on rebalancing the human–nature interactions that are central to the study and practice of ecological economics, which is the focus of the 2019 ANZSEE Conference in Melbourne later this month.


Australia was already one of the most urbanised nations by the end of the 19th century. Unlike European and North American countries, Australia’s pattern of settlement did not have a neat urban hierarchy. The gap between the large and small towns was huge.

These patterns have intensified in the decades since federation, especially after the second world war. International and internal migration trends have driven rapid growth in the big cities, especially Melbourne and Sydney. This has created major problems with providing adequate housing, infrastructure and services.

The fundamental issue is the reluctance of urban communities and their leaders to discuss what might be sustainable populations.




Read more:
If we want liveable cities in 2060 we’ll have to work together to transform urban systems


The folly of unlimited growth

No Australian city has a long-term vision showing how a future stabilised population might be supported with the essential resources of food, water and energy. No Australian city has faced up to the inevitable social tensions of increasing inequality between a well-served inner-urban elite and an increasingly under-resourced urban fringe.

Leaders in cities that have not grown as rapidly, such as Adelaide, lament their failure to grow like Sydney and Melbourne, despite all the associated problems. All implicitly believe unlimited growth is possible.

In reality, the expanding ecological footprints of the large cities have created unsustainable demands on land to support urban dwellers. And the wastes the cities produce are straining the capacity of the environment to handle these.




Read more:
What is ‘ecological economics’ and why do we need to talk about it?


Given the many unpriced flow-on effects from dense urban growth and market-led development, governments are struggling to deal with the undesirable consequences. Congestion and pollution threaten to overwhelm the many social and economic benefits of urban life.

The growth and concentration of populations are also driving chronic excess demand for appropriate housing. The result is serious affordability problems, which are adding to inequality across society and generations.




Read more:
50 years after The Lucky Country, Australia’s sustainability challenge remains


In 1970, urban historian Hugh Stretton pointed to the role of Australia’s widespread owner occupation in offsetting the inequalities generated in labour markets and by inherited wealth. This is no longer the case.

The dominant neoliberal economic ideology has resulted in a retreat from providing public housing. Abandoning would-be home-owners to the market has produced a situation in which urban land and house ownership is reinforcing class-based inequalities. Home ownership is increasingly the preserve of the affluent and their children.

Housing-related inequality is also seen in the geography of our cities. Poorer households are priced out of locations with better access to good jobs, schools, transport, health care and other services.




Read more:
Our big cities are engines of inequality, so how do we fix that?


Failures of governance

Governments in Australia’s federation are poorly placed to respond adequately. Responsibilities and fiscal resources are divided, creating obstacles to effective planning and infrastructure provision.

The main factor driving urban population growth is an unprecedented rate of inward migration. The national government sets large migration targets as an easy way of creating economic growth. This leaves state governments with the impossible task of meeting the resulting demand for infrastructure.

Jane O’Sullivan has shown each extra urban citizen requires about A$250,000 of investment. The total sum is well beyond the capacity of state and local governments.

Arguments between federal and state governments are heavily politicised, especially when it comes to major transport investments. Even within single jurisdictions, complex demands and unexpected consequences prevent effective action. The waste recycling crisis is a prime example.

State governments must also deal with difficult trade-offs between, for example, allowing further development on the edges of cities or encouraging higher density in built-up areas. This often involves conflicts with local governments and communities, concerned to protect their ways of life.

Australian planners and governments have long tinkered with policies to encourage decentralisation to smaller cities. Despite these attempts, the dominant pattern of urbanisation with its seemingly intractable problems has hardened, a triumph of reality over rhetoric.




Read more:
Our cities fall short on sustainability, but planning innovations offer local solutions


What needs to change?

To get beyond the rhetoric and make our cities more sustainably liveable requires a much more deliberate and interventionist role for government. It also requires residents of our cities and suburbs to be willing to allow their governments to interrupt business as usual.

This, we know from experience, is a big ask. It will step on the toes of the property lobby and ordinary home owners. In some cases, for example, the short-term financial interests of property owners are leading local authorities to ignore scientific warnings about the impacts of climate change on coastal development.




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Water may soon lap at the door, but still some homeowners don’t want to rock the boat


Major changes are also needed in how urban land is taxed and the proceeds invested. “Simple” reforms like replacing stamp duty on land transfer with a universal land tax, as the Henry Tax Review recommended, will take political courage that has been absent to date.

More complex policies like finding ways of diverting population growth to non-metropolitan regions will take careful thought and experimentation. This might include relocating government agencies to provincial cities. This has been tried sporadically in the past at the federal level and in states such as Victoria and New South Wales. However, such cases tend to be one-offs and do not reflect an overall strategic plan.

Future generations will inevitably be critical of the complete failure of current leaders to plan for sustainable development.The Conversation

Mike Berry, Emeritus Professor, RMIT University and Ian Lowe, Emeritus Professor, School of Science, Griffith University

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

Global bank urges cities to invest in new infrastructure to adapt to climate change



Our cities need to adapt to cope with more extreme weather events and other impacts from climate change.
Flickr/Shaun Johnston, CC BY-NC-ND

Elisa Palazzo, UNSW

The impacts of climate change on weather, sea levels, food and water supplies should be seen as an investment opportunity for our cities, says global investment banking firm Goldman Sachs.

In a report out last month the bank says cities need to adapt to become more resilient to climate change and this could “drive one of the largest infrastructure build-outs in history”.

The bank says cities will be on the frontline of any need to adapt because they are home to more than half the world’s population and generate roughly 80% of global GDP.




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The state of the debate

The report comes at a time when scepticism and wait-and-see approaches are still permeating the debate on climate action globally. The discussion on reducing emissions is dogged by disagreement on targets and actions to be undertaken.

Report cover.
Goldman Sachs

On the contrary, less emphasis has been placed on adapting to global warming, the consequences of which will play out for decades to come even if we meet the goals of the Intergovernmental Panel on Climate Change (IPCC).

Goldman Sachs has already said it acknowledges the scientific consensus that climate change is a reality and human activities are responsible for increasing concentrations of greenhouse gases in Earth’s atmosphere.

Much global attention has focused so far on the need for climate change mitigation and the reduction of CO₂ emissions. But the bank’s latest report addresses the urban adaptation strategies that are urgently required:

Greater resilience will likely require extensive urban planning, with investments in coastal protections, climate-resilient construction, more robust infrastructure, upgraded water and waste-management systems, energy resilience and stronger communications and transportation systems.

It acknowledges mitigation measures are essential to reduce global temperature in the medium and long term. But it argues we need to act immediately to minimise the current and future effects of climate change in urban areas.

The question is, why would a bank endorse such a vision?

Banking on climate change

The bank’s report is a collection of data and analysis on climate change from well-known sources, such as the IPCC, and a detailed list of expected impacts on cities.

For example, higher temperatures, more frequent and intense storms, and rising sea levels could affect economic activity, damage infrastructure and harm vulnerable residents.

Does the report represent a last call to brace for impact? Or is a more nuanced and somehow optimistic view of the process emerging?

In reality, it’s not surprising this call is coming from an international financial institution such as Golden Sachs. This report needs be read in parallel with the environmental policy framework of the bank which is its “commitment to addressing critical environmental issues”.

The latest report identifies urban adaptation responses and initiatives as market solutions and financial opportunities. It clearly points out where investments should be addressed.

The directions outlined range over infrastructural initiatives to measures that require financial investment. Our cities need better coastal protection, more resilient buildings and open spaces, sustainable water and waste management, and upgraded transport systems.

A call for action

There is a positive takeaway emerging from the bank’s viewpoint which is a pragmatic call for action.

This could reinstate a more optimistic view of climate change. It could overcome the wait-and-see approach by moving the discussions beyond mitigation only.

And the report has the merit to outline some major challenges emerging from the need of financing a comprehensive urban adaptation.




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Design for flooding: how cities can make room for water


First, the need for innovative sources of financing and new ways to support climatic transition.

Secondly, the need to look at equity issues emerging from an adaptation process. For example, should a city strengthen flood defences in the CBD or should it upgrade public housing in flood-prone areas? Given the scale of the aims we need to evaluate carefully where best to invest the limited resources available.

But in this respect, no solutions are proposed.

This report is one of the many financial reports on climate change we have seen recently, about the risks and opportunities for the banking and insurance system. It’s probably the first to acknowledge clearly the need for comprehensive adaptation investments to make our cities more resilient.

But in concentrating on the infrastructure needs for cities, the report seems to miss the big picture.

There is still a need to understand how more integrated actions will include the social and environmental dimensions of adapting to climate change to create more sustainable and equitable cities.The Conversation

Elisa Palazzo, Senior Lecturer, Faculty of Built Environment, UNSW

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

Keeping the city cool isn’t just about tree cover – it calls for a commons-based climate response



Where’s the shade? Trees are not an immediate or whole answer to keeping cool.
Cameron Tonkinwise, Author provided

Abby Mellick Lopes, Western Sydney University and Cameron Tonkinwise, University of Technology Sydney

This story is part of Covering Climate Now, a global collaboration of more than 250 news outlets to strengthen coverage of the climate story.


A recent report by the Greater Sydney Commission singles out urban heat as one of four priority areas given our coming climate. It identifies tree canopy as the top response for reducing city temperatures and delivering amenity. However, the public conversation about urban heat often misses the complex relationship between trees, people and the built environment, which challenges this response.

In soon-to-be-published research supported by the Landcom University Roundtable we found that responding to a more extreme climate requires new social practices and new relationships with the commons. Commons are the spaces, resources and knowledge shared by a community, who are, ideally, involved in the regeneration and care of those commons. Trees are an important social commons, but they also present multiple challenges.




Read more:
Our cities need more trees, but some commonly planted ones won’t survive climate change


Closing our doors to the great outdoors

For one, trees are an outdoor amenity, but we are spending more and more time indoors. For those who can afford it, air conditioning delivers cooling in the privacy of your own home or car – no need for trees.

However, staying in cool bedrooms and car rides mean less time outdoors and with others, which isn’t ideal for human health and well-being.




Read more:
Increasing tree cover may be like a ‘superfood’ for community mental health


Air conditioning also uses more fossil-fuel-based energy, which generates more greenhouse gas emissions. The result is more climate change.

Mixed feelings about trees

As the Greater Sydney Commission report makes clear, tree canopy in Greater Sydney is roughly proportional to household wealth. The “leafy suburbs” are the wealthier ones. This means tree planting is an important investment in less wealthy parts of the city, which experience more extreme heat days.

Number of days over 35°C recorded in various parts of Greater Sydney (July 2018-June 2019).
© State of NSW through the Greater Sydney Commission



Read more:
In a heatwave, the leafy suburbs are even more advantaged


However, research also shows people have mixed feelings about trees. In comparison to the neat shrubbery and easily maintained sunny plazas we’ve become used to in our cities, trees can be “messy” and “unpredictable”. Leaf litter can be slippery and natives like eucalypts, with their pendulous leaves, provide limited shade. People worry about large trees falling over or dropping branches.

Trees are often at the centre of disputes between neighbours. They can also be perceived as a security problem – if trees reduce visibility they might provide cover for wrongdoers.

In addition, insurance companies can charge a premium if a property is deemed at risk of damage by large trees. As we experience more extreme weather, laws on vegetation clearing are becoming more risk-averse.




Read more:
If planners understand it’s cool to green cities, what’s stopping them?


What trees where and when?

Urban development tends to give priority to roads and delivering the maximum number of dwellings on sites. This leaves little space for trees, which need to fit into crowded footpaths with ever-changing infrastructures. For example, will larger trees interfere with 5G?

When juggling priorities in the streetscape, trees often lose out.




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Trees versus light rail: we need to rethink skewed urban planning values


It’s an obvious point, but trees take time to grow. It can take many years for a planted sapling to become a shade tree. In that time there will be no shelter from the heat.

Also in that growing period, which can sometimes be unpredictable, trees need to be nurtured, especially in times of drought. And, once the tree is mature, fingers crossed that extreme weather events do not undo all those years of waiting.

So, while increasing tree canopy sounds like an obvious solution, trees are in fact a complex social challenge. In our research, we point to ways some of these tree-related tensions can be managed.

Shade in the meantime

A structure to support fast-growing vines has been built on one of Darwin’s hottest streets, but even these will take some time to grow.
Darwin We Love It/Facebook

Shade is an important civic resource. Large, mature trees with spreading canopy provide the best shade, so strategic construction bans and tree preservation orders are an obvious first step.

However, if shady canopy is decades off, we need to think about other, creative ways to provide shade in the meantime to ensure, for example, that people of diverse abilities can walk their city in reasonable comfort. This might include temporary shade structures such as awnings, bus shelters and fast-growing vine-trellised walkways (if there is space to create troughs for soil and the structure doesn’t cause access problems).

And, as the Cancer Council consistently reminds us, we all need to adopt more climate-defensive clothing.




Read more:
Requiem or renewal? This is how a tropical city like Darwin can regain its cool


An important alternative is to follow our regional neighbours and start to populate parks and other public spaces at night. This suggests a need for removable shade, so we can take part in activities like stargazing.

Cultivating an intergenerational commons

Mature trees can die back or die altogether, so other trees should be maturing to take their place. Usually, experts design and maintain landscapes for others to enjoy.

However, users of the cooling services of parks could be invited into the process of planning and realising landscape designs. This would give them a say on the trees of which they have “shared custody”. Planting for succession can create an intergenerational sense of ownership over a shared place.

Current planning practices tend to ignore wind and solar patterns. The result is urban forms that make heat worse by prioritising comfortable private interior spaces over the commons of public space. Designing cool cities means using trees, water and buildings to create cool corridors that work with cooling breezes – or even summon these in still, heat-trapping basins like Western Sydney.




Read more:
How people can best make the transition to cool future cities


These few examples point to new ways of living with trees as social commons, but they also point to new forms of commoning – collaborative forms of care and governance that invite people to adopt new social practices better suited to living well in the coming climate.

It is a positive step that state development agencies like Landcom aim to demonstrate global standards of liveability, resilience, inclusion, affordability and environmental quality. In so doing, they initiate transitions to these more commons-based ways of living.


In addition to the authors of this article, the Cooling the Commons research team includes: Professor Katherine Gibson, Dr Louise Crabtree, Dr Stephen Healy and Dr Emma Power from the Institute for Culture and Society (ICS) at Western Sydney University (WSU), and Emeritus Professor Helen Armstrong from Queensland University of Technology (QUT).The Conversation

Abby Mellick Lopes, Senior Lecturer in Design, Western Sydney University and Cameron Tonkinwise, Professor, School of Design, University of Technology Sydney

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

Urban growth, heat islands, humidity, climate change: the costs multiply in tropical cities



During a heatwave in late 2018, Cairns temperatures topped 35°C nine days in a row and sensors at some points in the CBD recorded 45°C.

Taha Chaiechi, James Cook University and Silvia Tavares, James Cook University

Some 60% of the planet’s expected urban area by 2030 is yet to be built. This forecast highlights how rapidly the world’s people are becoming urban. Cities now occupy about 2% of the world’s land area, but are home to about 55% of the world’s people and generate more than 70% of global GDP, plus the associated greenhouse gas emissions.

So what does this mean for people who live in the tropical zones, where 40% of the world’s population lives? On current trends, this figure will rise to 50% by 2050. With tropical economies growing some 20% faster than the rest of the world, the result is a swift expansion of tropical cities.

Population and number of cities of the world, by size class, 1990, 2018 and 2030.
World Urbanization Prospects 2018, United Nations DESA Population Division, CC BY



Read more:
Healthy, happy and tropical – world’s fastest-growing cities demand our attention


The populations of these growing tropical cities already experience high temperatures made worse by high humidity. This means they are highly vulnerable to extreme heat events as a result of climate change.

For example, extremely hot weather overwhelmed Cairns last summer. By December 3 2018, the city had recorded temperatures above 35°C nine days in a row. Four consecutive days were above 40°C.

Cairns’ heatwave summer.
Authors, using BOM temperature data

For our research, temperature and humidity sensors were strategically placed in the Cairns CBD to represent people’s experience of weather at street level. These recorded temperatures consistently higher than the Bureau of Meteorology (BoM) recordings, reaching 45°C at some points.

Highest temperatures recorded by James Cook University weather data sensors during the November-December 2018 heatwave in Cairns.
Image: Bronson Philippa, Author provided

Local effects magnify heatwave impacts

Urban environments in general are hotter than non-urbanised surroundings that are covered by vegetation. The trapping of heat in cities, known as the urban heat island effect, has impacts on human health, animal life, social events, tourism, water availability and business performance.

The urban heat island effect intensifies the impacts of increasing heatwaves on cities as a result of climate change.

Projections of increased heatwave frequency for Cairns region using visualisation platform on Queensland Future Climate Dashboard.
Queensland Future Climate Dashboard/Queensland Government, CC BY

But it is important to remember that other local factors also influence these impacts. These include the scale, shape, materials, composition and growth of the built environment in a particular location and its surrounding areas.

The differences between the BoM data recorded at Cairns airport and the inner-city recordings show the impacts of urban expansion patterns, built form and choice of materials in tropical cities.

The linear layout of Cairns has, on one hand, enabled the formation of attractive places for commercial activities. As these activity centres evolve into focal points of urban life, they in turn influence all sorts of socioeconomic parameters.

On the other hand, the form the built environment takes changes the patterns of wind, sun and shade. These changes alter the urban microclimate by trapping heat and slowing or channelling air movements.

The layout and structures of Cairns CBD alter local microclimates by trapping heat and altering air flows.
State of Queensland 2019, CC BY



Read more:
City temperatures and city economics, a hidden relationship between sun and wind and profits


Shifting the focus to the tropics

To date, a large body of research has explored the undesired consequences of climate change and urban heat islands. However, the focus has been on capital and metropolitan cities with humid continental climates. Not many studies have looked at the economic and social impacts in the tropical context, where hot and humid conditions create extra heat stress.

Add the combined effects of climate change and urban heat islands and what are the socio-economic consequences of heatwaves in a tropical city like Cairns? We see that climate change adds another dimension to the relationship between cities, economic growth and development.

This presents a huge opportunity to start thinking about building cities that are not superficially greenwashed, but which instead tackle pressing issues such as climate variability and create sustainable business and social destinations.




Read more:
Requiem or renewal? This is how a tropical city like Darwin can regain its cool


In cold climates, heatwaves and urban heat islands are not necessarily undesired, but their negative impacts are more obvious and harmful in warmer climates. And these harmful impacts of heatwaves on our economy, environment and society are on the rise.

We have scientific evidence of the increasing length, frequency and intensity of heatwaves. The number of record hot days in Australia has doubled in the past five decades.

Projections of changes in heatwave frequency for northern Queensland in 2030 and 2070.
Queensland Future Climate Dashboard/Queensland Government, CC BY

What are the costs of heatwaves?

Increased exposure to heatwaves amplifies the adverse economic impacts on industries that are reliant on the health of their outdoor workers. This is in addition to the extreme heat-related fatalities and health-care costs of heatwave-related medical emergencies. As a PwC report to the Commonwealth on extreme heat events stated:

Heatwaves kill more Australians than any other natural disaster. They have received far less public attention than cyclones, floods or bushfires — they are private, silent deaths, which only hit the media when morgues reach capacity or infrastructure fails.

Heat also has direct impacts on economic production. A 2010 study found a 1°C increase resulted in a 2.4% reduction in non-agricultural production and a 0.1% reduction in agricultural production in 28 Caribbean-basin countries. Another study in 2012 found an 8% weekly loss of production when the temperature exceeded 32°C for six days in a row.

The 2017 Farm performance and climate report by the Australian Bureau of Agricultural and Resource Economics and Sciences (ABARES) states:

The recent changes in climate have had a significant negative effect on the productivity of Australian cropping farms, particularly in southwestern Australia and southeastern Australia.

Average climate effect on productivity of cropping farms in southwestern and southeastern Australia since 2000–01 (relative to average conditions from 1914–15 to 2014–15).
Farm performance and climate, ABARES, CC BY

It’s not just farming that is vulnerable. A Victorian government report report this year estimated an extreme heatwave event costs the state’s construction sector A$103 million. The impact of heatwaves on the city of Melbourne’s economy is estimated at A$52.9 million a year on average.

Impacts of heatwaves on Victoria’s main economic sectors.
State of Victoria Department of Environment, Land, Water and Planning, CC BY

According to this report, economic costs increase exponentially as the severity of heatwaves increases. This has obvious implications for cities in tropical regions.

As the next step in our research, we are examining the relationship between local urban features, urban heat islands, the resulting city temperatures and their direct and indirect (spillover) effects on local and regional economic activities.




Read more:
Making a global agenda work locally for healthy, sustainable living in tropical Australia


The Conversation


Taha Chaiechi, Senior Lecturer, James Cook University and Silvia Tavares, Lecturer in Urban Design, James Cook University

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

We have the blueprint for liveable, low-carbon cities. We just need to use it



Increasing heat in Sydney and other Australian cities highlights the urgent need to apply our knowledge of how to create liveable low-carbon cities.
Taras Vyshnya/Shutterstock

Deo Prasad, UNSW

Over the past seven years more than 100 research projects at the Co-operative Research Centre for Low Carbon Living, in collaboration with industry across Australia, have pondered a very big question: How do we build future cities that are sustainable, liveable and affordable?

This is exactly what Australians want, as the recent Greater Sydney Commission report, The Pulse of Greater Sydney, revealed. People want cities in which they live close to jobs and have reasonable commuting times. They want access to parks and green space, and relief from ever-increasing urban heat.




Read more:
If we want liveable cities in 2060 we’ll have to work together to transform urban systems


The good news is we already know what it will take to deliver on much of this wish list. Since 2012, I have headed the A$100 million Low Carbon Living CRC, which has brought together Australian businesses, industries, communities and many of our brightest researchers to work out how to steer change.

Our Cooling Sydney Strategy, for instance, is the result of years of research into how to combat urban heatwaves. The burden of this heat is unevenly spread across our cities.

For example, residents of Sydney’s western suburbs are exposed to many more days hotter than 35 degrees than Sydneysiders living in the CBD and the city’s north. Last summer that meant over a month’s worth of intense heat in the suburb of Penrith, including nine days in a row above 35°C.




Read more:
Building cool cities for a hot future


While the recent winter sun might feel welcome, the negative impacts of increasingly hot cities on our health, lifestyle and energy use greatly outweigh any winter comfort.

So what are the solutions?

Our researchers have already found how we can offset increasing heat. The strategies includes cool and permeable pavements, water features and evaporative cooling, shade structures, vertical gardens, street trees and other plants – even special heat refuge stations.

Keeping cool inside, without huge power bills, is possible too. During last summer’s heatwave, our pilot 10-star energy-efficient house in Perth remained a comfortable 24°C inside, without air conditioning, when it was over 40°C outside. The exceptional thermal performance of the house was down to its evidence-based design.

Josh Byrne explains how his house keeps temperatures comfortable year-round with low energy use and no net emissions.



Read more:
When the heat is on, we need city-wide plans to keep cool


This work is just one part of our wider remit. Our UNSW-based centre is on track to deliver independently verified cuts of 10 megatonnes of carbon emissions generated by Australia’s built environment by 2020. By integrating renewable energy systems, smart technologies, low-carbon materials and people-centred design into buildings and urban precincts, we have developed a sustainable, liveable and affordable urban blueprint for Australia. A PwC study (yet to be released) estimated cumulative economic benefits totalling A$684 million by 2027.

To put this another way, we have identified and verified evidence-based pathways to cut emissions equivalent to taking some 2.1 million cars off the road.




Read more:
Cutting cities’ emissions does have economic benefits – and these ultimately outweigh the costs


Some of the progress to date is not immediately obvious to the casual observer. Take an otherwise unremarkable stretch of road along the back way to Sydney Airport. Recently, a 30-metre section of concrete was installed, which looks more like an ad hoc road repair than an important scientific pilot study.

Bu 15 metres is paved with a new geopolymer concrete that slashes greenhouse gas emissions by 50%. The other 15 metres is conventional concrete, the most widely used man-made material on the planet. Concrete production, using cement as its binder, accounts for about 8% of all global emissions.

The geopolymer concrete developed through our research centre is a similarly high-performance product but its binder safely incorporates otherwise noxious industrial waste streams, such as fly ash from coal-fired power stations and slag from blast furnaces. Australia has stockpiled about 400 million tonnes of waste from coal-fired power generation and steelmaking.

In Alexandria, in collaboration with the City of Sydney, we are testing this low-carbon concrete as a road surface that could help clean up industrial waste while slashing emissions. Working with NSW Ports, we’ve also shaped it into low-carbon bollards to form a breakwater to protect the coastline at Port Kembla from extreme weather.

Waste from coal-fired power stations has been used to make low-carbon bollards to protect the coastline at Port Kembla.

We now have the know-how to do better

There are many such success stories, but with 150 CRC Low Carbon Living projects the list is too long to detail. What’s more important, as our funding period comes to an end and Australia loses its only innovation hub committed to lowering carbon in the built environment, is to note how we got to where we are today.

The federal government’s Co-operative Research Centre program fosters co-operation and collaboration on a grand scale. Industries, businesses, government organisations and communities with a stake in solving big, complex challenges partner with researchers from a wide range of academic fields. This structure brings together sectors and people whose paths might otherwise rarely cross.

The cross-fertilisation of ideas, expertise and skills delivers innovative solutions. Research worldwide has consistently shown that collaboration drives innovation, and that innovation drives economic growth. Our experience confirms that as we partnered with organisations such as Multiplex, AECOM, BlueScope Steel, Sydney Water, ISCA, CSIRO and the United Nations Environment Program.

Cities are complex, exciting beasts, but we have the knowledge and expertise to live better, more comfortable urban lives in Australia while reducing demand for energy, water and materials. That is, we have the blueprint for low-carbon urban living. We must now choose to use it.


This article has been updated to correct the number of CRC Low Carbon Living projects to 150 and the amount of stockpiled waste from coal-fired power generation and steelmaking to 400 million tonnes.The Conversation

Deo Prasad, Scientia Professor and CEO, Co-operative Research Centre for Low Carbon Living, UNSW

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

Our cities need more trees, but some commonly planted ones won’t survive climate change


Australian cities could lose some of their most common trees to climate change.
Jamen Percy/Shutterstock

Alessandro Ossola, Macquarie University; Hugh Munro Burley, Macquarie University; Leigh Staas, Macquarie University; Linda Beaumont, Macquarie University; Michelle Leishman, Macquarie University, and Rachael Gallagher, Macquarie University

We need trees in our lives. This past summer, Adelaide experienced the hottest temperature ever recorded in an Australian state capital, hitting 46.6 degrees on January 24. Trees beautify otherwise grey cities and cool our suburbs during heatwaves. But different species have different levels of tolerance of heat, lack of water and other threats posed by climate change.

In a newly published study, we investigated likely climate change impacts on 176 of the most common tree species planted across Australian cities. Our analysis showed more than 70% of these species will experience harsher climatic conditions across Australian cities by 2070. Some of the most commonly planted trees are unlikely to survive these conditions.

The golden wattle might struggle in our northern cities if they get hotter and drier.
Dryas/Wikimedia Commons, CC BY-SA

So which tree species are best suited to particular places? Which species are more likely to thrive, rather than just survive, under a changing climate? Which of our beloved tree species won’t make it?

Tree species growing in warmer cities are more likely to be affected than those in cooler cities. Some species, such as the golden wattle (Acacia longifolia) or the prickly paperbark (Melaleuca styphelioides), might not make it in northern cities, unless we invest precious resources – such as water – to maintain these civic assets. Other species, such as the native frangipani (Hymenosporum flavum) or the tuckeroo (Cupaniopsis anacardioides), will likely become more suitable for planting in southern cities.




Read more:
We’re investing heavily in urban greening, so how are our cities doing?


Why do cities need trees?

Trees are wonderfully effective at improving the microclimate of our cities, which makes tree plantings an effective and efficient way to adapt to climate change. The leaves of trees absorb and dissipate much of the sun’s radiation.

Trees cool air and land by several degrees compared to areas of concrete and asphalt. Swipe the heat map below to see how effectively trees cool down our cities. (Red indicates hotter areas, blue cooler areas.)

Swipe the map to see how much trees cool urban areas. Red indicates hotter areas, blue cooler areas. This temperature map was collected during a heatwave in Adelaide, South Australia, on February 9 2017 by AdaptWest over the cities of West Torrens, Charles Sturt and Port Adelaide-Enfield.
Used with permission of AdaptWest Adelaide (https://www.adaptwest.com.au/mapping/heat-maps)



Read more:
Building cool cities for a hot future


Governments recognise the importance of trees and have developed vital initiatives, such as the national 20 Million Trees program and the 5 Million Trees program in New South Wales. These are important first steps to increase urban tree cover across Australia. But the question arises: are we planting the right tree species?

What does the science say?

Australian cities are blessed with a higher diversity of tree species compared to other cities globally. However, the 30 most commonly planted species make up more than half of Australia’s urban forests.

This poses a great risk for our cities. If we were to lose one or two of these common species, the impact on our urban tree cover would be immense. Consequently, our best insurance is to increase the diversity of our trees.

Species composition of Australia’s urban forests across 60 local government areas. The size of each word is proportional to the number of tree stems recorded for each species.
Alessandro Ossola

Our quest to find climate-ready tree species is only just beginning. Supported by Hort Innovation Australia, the NSW Department of Planning, Industry and Environment, and the Commonwealth government, our team embarked on a project called Which Plant Where in conjunction with researchers at Western Sydney University. Our mission is to find the best plant species for urban landscapes that will be resilient to climate change.

We work with the nursery industry to provide evidence on species’ resilience to extreme heat and drought by testing plants to their limits in research glasshouses. Our work with plant growers and nurseries will inform them on how to adapt their business, by identifying the new challenges posed by climate change, as well as selecting highly diverse palettes of climate-ready species. We advise landscape architects, designers and urban planners about not only the best planting choices, but also how to increase the biodiversity of our cities.




Read more:
For green cities to become mainstream, we need to learn from local success stories and scale up


You can help!

We are committed to do more science in coming years, but you can start making a difference today. Australia’s National Tree Day will be celebrated again this year on Sunday, July 28. It’s a great opportunity to teach our families, communities and businesses about the importance of tree planting and environmental stewardship as key elements of adapting to climate change.

An old Chinese adage says:

The best time to plant a tree was 20 years ago. The second best time is now.

This weekend is your time. The game is simple – head to your closest plant nursery. Ask your local grower about which tree species are suitable for the local growing conditions and pick one you like. Then, plant a tree in your yard, or join one of the many planting events across Australia.

Teach your kids, family and friends about the difference they can start making today – for their future and our common good – one tree at a time. The Conversation

A plant nursery growing a diverse range of tree species for the upcoming planting season.
Alessandro Ossola

Alessandro Ossola, Research Coordinator Centre for Smart Green Cities, Macquarie University; Hugh Munro Burley, Spatial analyst, Macquarie University; Leigh Staas, Associate Director for Engagement & Research Partnerships | Smart Green Cities, Macquarie University; Linda Beaumont, Senior Lecturer, Macquarie University; Michelle Leishman, Distinguished Professor, Head of Department, Macquarie University, and Rachael Gallagher, , Macquarie University

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

For green cities to become mainstream, we need to learn from local success stories and scale up



Melbourne has a rich legacy of urban parks thanks to planning decisions made when the city was first established.
Shutterstock

Jason Alexandra, RMIT University

Greening our cities has become one of the great global imperatives of the 21st century including to tackle climate change. And Australia’s sprawling car-based cities are gradually changing to embrace green or living infrastructure.

Green cities bring together elements of architectural design and urban planning, often combining plants and built infrastructure to meet the needs of humans, such as our love of nature.




Read more:
Australian cities are lagging behind in greening up their buildings


Trees, plants, waterways and wetlands can deliver climate conditioning, cooling cities by reducing the urban heat island effect. They also absorb carbon dioxide, filter wastewater and create habitats.

Living elements can be incorporated with built infrastructure at a range of scales, from individual buildings with green walls and roofs, through to citywide strategies. And there are a suite of strategies to guide more widespread integration of biological elements and ecological processes in cities.

In recent months, we profiled Australian examples of living infrastructure that show some of Australia’s approaches to developing green infrastructure, from greening Melbourne’s laneways to Canberra’s urban forest. These cities are already redesigning their water systems and implementing urban forest strategies to create green belts and protect and restore waterways.

Melbourne and Canberra provide some useful examples of the green cities movement, but to make it mainstream, these techniques need to be adopted widely through policies supporting more holistic and better integrated urban planning.

Why we need urban forests

Percival Alfred Yeoman was one of the first Australian pioneers of urban forestry. In 1971, he articulated a clear vision for enhancing cities with trees.




Read more:
Why ‘green cities’ need to become a deeply lived experience


Local governments in Adelaide, Brisbane, Melbourne and Sydney, are implementing his ideas, committing to ambitious increases in urban canopy cover. Their targets range from 25% to 40%.

This revived interest in urban forestry comes from its well documented potential for accelerating the transition to more climate adaptive cities.

The social, environmental and economic benefits of urban trees, or “ecosystem services”, are becoming better recognised, including for their recreational and cultural values.

Melbourne and Canberra are leading Australia’s green cities movement

Melbourne

Melbourne has a rich legacy of urban parks and green belts thanks to planning decisions made in the city’s early years.




Read more:
Urban greening can save species, cool warming cities, and make us happy


These parks underpin a new wave of urban greening, with projects that aim to deliver action on climate change, biodiversity and the health and well-being of communities.

The Melbourne green infrastructure plan includes:

  • a “growing green guide” that provides practical advice to community and business groups on planning, design and maintenance of green infrastructure

  • the greening laneways strategy, which builds on the commercial revitalisation of Melbourne’s laneways over three decades. Laneways with greening potential were mapped and demonstration project developed to display techniques for making them more vibrant green spaces for business, tourists and locals to enjoy

  • an urban forest strategy, with an overall target of 40% canopy cover by 2040. And 5 to 8 million trees will be planted over coming decades for the greater Melbourne metropolis.

Canberra

Canberra is often described as “a city within a landscape” and the “bush capital”. But its higher altitude, hot dry summers and cold winters bring a set of challenges for green infrastructure.

With more than 800,000 planted trees, Canberra is an urban forest. But these trees require special care and attention given they are ageing and suffering from a hotter, drier climate.




Read more:
How do we save ageing Australians from the heat? Greening our cities is a good start


Wildfire also represents a significant risk where urban and rural areas connect. This means Canberra needs urban forests that will cool the city in warmer months without also escalating wildfire risks.

The ACT Government has committed to action on climate change, legislating targets for 100% renewable electricity by 2020 and carbon neutrality (no net carbon emissions) by 2045.

With more than 800,000 trees, Canberra is an urban forest.
Shutterstock

Integrated approach needed to expand green cities

Greening cities requires a holistic approach – for instance, not leaving the health of waterways entirely to water engineers.

Greening cities is more than just a technical challenge. Transforming the form and functions of urban systems, through urban forests and other living infrastructure, requires greater leadership and political commitment, integrated planning and community participation, and long-term thinking.

An integrated approach to greening cities involves mapping diverse opportunities and mobilising support for change in the community. As an example, urban storm water can be a productive resource when used in constructed wetlands or to irrigate urban forests.

The vertical gardens in One Central Park in Sydney are globally renowned for their green infrastructure.
Shutterstock

And often urban drainage lines and wastelands can be transformed into green spaces, but it’s worth recognising there is intense competition for space for housing.

But for more widespread adoption of integration, institutional support within local governments and metropolitan water and planning agencies is needed.

So to scale up living infrastructure in our urban landscapes, we must learn from local success stories, conduct more research, and better understand how to deal with climate adaptation and mitigation challenges.




Read more:
If planners understand it’s cool to green cities, what’s stopping them?


Jason Alexandra would like to gratefully acknowledge the contributions of Barbara Norman to this article.The Conversation

Jason Alexandra, PhD candidate, RMIT University

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