We have all the ‘nature’ solutions we need to make our sweaty cities cooler, while giving our economy a much-needed green boost.
Temperature check
Parts of Sydney may be too hot to live in within decades — as temperatures soar closer to 50°C. And it’s not just Western Sydney. The hottest days in Brisbane and Melbourne are expected to frequently reach over 40°C by 2060–2080.
Summer heatwave. Photo: Lunatictm
The hardest hit will be suburbs already vulnerable to heatwaves because of the heat island effect.
Heat islands are places where roads, roofs and footpaths outnumber leafy trees and green corridors. Where man-made surfaces absorb and hold heat, not cooling down at night. And where traffic and industry add to the heat.
Heatwaves kill more Australians than any other natural disaster and these will get more severe as our climate continues to change.
It’s easy to see how this can give rise to a feeling of despair among those who live in a sweltering suburb. Not to mention the cost of a heatwave to our economy, our wellbeing and our urban wildlife.
Natural solutions
There are simple ways we can lower temperatures in cities. We can start with growing more trees, shrubs and grasses — in streets and parks or on walls and roofs. And we can strengthen our nature laws to protect the green corridors we already have.
Three of Australia's major cities are already taking steps we can learn from.
- In Sydney the Cool Streets© initiative is partnering with Blacktown City Council to explore how suburban streets can use nature to turn down the heat, engaging residents in the process. A few simple changes to a street design could reduce emissions, cool neighbourhoods and lower electricity bills for residents by $249 over time. Leafy streets could also lower projected daily hospital admission rates for heatstroke by 30% and dehydration by 15%. And local pavements, roads and other infrastructure are less likely to degrade under heat stress.
“Houses may be getting larger as gardens get smaller, but the streets are still ours to make cool,” says the founder of Cool Streets© initiative Libby Gallagher.
“The important thing is working with communities in the process so they see the benefits and are invested in greening and cooling their homes and streets around them.”
Cool Streets© engaging the community in Blacktown. Photo: Matthew Duchesne
- In Melbourne 32 local councils have signed up to the Living Melbourne Forest Strategy as an antidote to the decline of green space across the city, and to challenge how the city meets a growing population. Participating councils are committed to growing an urban forest of native trees, shrubs and grasslands on public and private land. And they are encouraging their communities with local projects everyone can contribute to.
Community planting, Melbourne. Photo: Annette Ruzicka/MAPgroup
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Hobart and Canberra are the only Australian cities that have more vegetation in 2020 than in 2013. Hobart City Council already had a long-term established vision to grow an urban forest and create a city that is clean, green, healthy, attractive, energy efficient, sustainable and less polluted. The perfect ingredients for any city looking to mitigate rising temperatures.
Why greening works
Green skyscraper. Photo: tostphoto
So often nature offers the best solutions. Greening our cities alone is not enough to mitigate hotter temperatures, but more trees, gardens and wetlands can reduce average maximum peak daily temperatures by up to 1.8 degrees celsius and night temperatures by up to 2.3 degrees, while reducing emissions.
Plus ‘greening’ our cities can create much-needed jobs to help our economic recovery. Investing $2.4 billion in landscape management and restoration could create 24,000 jobs in the sector in the first year of operation.
Greening our cities is projected to create 24,000 jobs to help our economic recovery.
Let's get moving
Despite all the communities, businesses and local councils getting on board, Australian cities lag behind other countries when it comes to greening and cooling cities.
Volunteer tree planting. Photo: Annette Ruzicka/MAPgroup
“Improving green cover across all parts of our cities while taking strong action on climate change are urgent tasks if Australia’s most populated centres are to protect the health and wellbeing of our communities in the coming decades,” says Monash University’s Lucy Richardson.
But cities also need to protect their remaining native plants and trees, and Australia’s national environmental law is allowing the destruction of trees that could be cooling cities and providing critical habitat for urban wildlife.
In the first 17 years that Australia had a national environment law, 20,212 hectares of urban threatened species habitat — that’s 11,400 MCG footy grounds — was destroyed.
Australia’s national environmental law is allowing the destruction of native trees that could be cooling cities.
Greening our cities won’t solve all our climate problems, but it will contribute to a cooler and more liveable future. With 90% of Australian living in urban areas — 60% of us in cities of one million or more — why would we not make use of the solutions we have at our fingertips?
Read the full report by Monash University and ACF: Temperature Check: Greening Australia's warming cities.
