The New South Wales regional city of Wagga Wagga has used innovative technology to find a cooler way forward as global temperatures climb.
Wagga Wagga City Council recently won the Local Government NSW Excellence in the Environment Award for its Urban Cooling Strategy 2022-2052, a plan that aims to limit the impacts of climate change using “urban cooling tools” such as tree planting, artificial shade, use of water and cooler materials.
The strategy combined tree canopy imaging, aerial and heat mapping to look at 27 of the city’s suburbs, to identify those that need help. The aim is to use the information to plan a cooler future.
“The Urban Heat and Canopy mapping tool is a great way for the community to see current land surface temperatures and canopy heights, and then implement cooling mechanisms from the Action Summary Table,” Wagga Wagga City Council environmental monitoring officer Jason Carroll says.
“Council has already started to implement actions from the document including planting trees around local parks and along Active Travel Paths to help cool the city.”
The strategy includes an interactive map that allows residents to type in their address and view it on an infrared heat map. It has also profiled Wagga Wagga’s suburbs and given each a rating based on the percentage of canopy cover, and another on the land surface temperature.
The Council’s Environment and Regulatory Services Manager Mark Gardiner says the Council started the strategy to help achieve its 2050 net zero target.
“Everything seems to be getting hotter, and there are predictions it will be hotter again in 2024,” Gardiner says.
“In preparation for that, we wanted to make our community more resilient and better able to cope with those hotter days. It’s a well-known fact that under a tree canopy, it can be anything up to 10 degrees cooler – that makes a big difference on a 40-degree day.”
The council contracted environmental consultants ArborCarbon, who used an 11-band airborne multispectral camera system to capture images more than 4800 metres above ground level on cloudless days.
During the study period of February 2023, the highest temperature recorded was 29.3⁰C.
The airborne imaging determined a baseline current canopy cover that Council could then compare with their own aerial mapping.
Gardiner says in some cases it was “eye-opening” to see the aerial, heat mapping and canopy maps align.
“Where we are finding the heat coincides with the areas of dark roofs and a lack of canopy, particularly across urban areas,” he says.
Newer suburbs with less vegetation or newly planted vegetation were also higher temperature zones.
Suburb statistics showed a range in canopy cover from 17% in the suburb of Moorong, to less than 2% in Bomen. The land surface temperature ranged from about 31% in Forest Hill, down to less than 28% in Kapooka.
The $158,000 strategy was funded through the Increasing Resilience to Climate Change grants and Wagga Wagga City Council. Gardiner says he believes an urban cooling strategy is achievable for other large regional cities to help address the challenges of climate change and urban heat.
The council’s 30-year plan includes actions such as planning for more sustainable neighbourhoods, increasing canopy coverage on public and private land, and increasing awareness of urban cooling tools.
The Greenlight Project is a year-long look at how regional Australia is preparing for and adapting to climate change.