The Victorian state government has announced new protections for urban tree canopy, which is an important factor in keeping cities cool. An RMIT expert explains why this type of initiative is important in future proofing Australian cities.
Dr Thami Croeser, Vice Chancellor's Postdoctoral Research Fellow
"It's fantastic that the state government is moving to protect existing trees across Melbourne, especially given that this week's National Climate Risk Assessment report warned of devastating heatwaves in the future.
"Trees can help mitigate these climate issues by acting as big outdoor air conditioners. But to see significant cooling we need a threshold of about 40 per cent canopy within 60 metres of a home.
"It's around this threshold that there is enough shade and water being sucked up and blown out of the leaves to avoid 'heat island' effects associated with lots of unshaded concrete and tarmac.
"Currently, only a fraction of homes meet this threshold in Melbourne, and many suburbs are way short of this level, at 10 per cent canopy or below.
"It's very easy to diminish a city's canopy, so the state government's plan to protect more urban trees is an important step in the right direction. Careful monitoring of the initiative will be critical to ensure we close any loopholes and find win-win ways to retain tree canopy while also constructing new housing."
Dr Thami Croeser is an urban planner with a focus on practical, large scale initiatives to improve nature in city areas.
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