Sydney’s extreme weather forewarns of the need to cool our suburban streets
Extreme weather temperatures in late October have left Sydney in anticipation of the sweltering summer to come. The day before Halloween, temperatures reached 35.4⁰C, which is 13⁰C above the October average.
Extreme weather is a reminder of the gradual effects of climate change on our city. A recent study by the Australian National University warned Sydney and Melbourne to prepare for scorcher days reaching 50⁰C by the end of the century, even if global warming is contained to the Paris Agreement target of 2⁰C.
Heat is already Australia’s number one climate killer. More people are killed by heat each year than they are by bushfires. More than 370 deaths were directly attributable to the heatwaves of 2009 alone.
It is particularly dangerous in urban environments, where dark buildings, roads and infrastructure combine to absorb heat and restrict airflow. Black roads can be up to 30⁰C hotter at the surface than forecast temperatures. ‘Heat continents’ are likely to occur in suburban areas, with suburbs remaining hot for significant periods of time without relief.
Street Coolers is a not for profit sustainability campaign whose goal is “to bring sustainable thinking into the social consciousness of Australia, and encourage the development of cool city and suburban blocks that link up to form cooler and more liveable cities that simultaneously reduce overall energy consumption.”
The initiative is run by sustainability campaigner, Michael Mobbs. He has trialled a lighter coloured bitumen in Redfern, which reduces temperatures by 2-4⁰C on a hot day. White roofs are another option which work to reflect the sun’s rays. The group is also working to increase shading by trees on urban streets. Their research found that surface level temperatures in the shade were on average 9⁰C cooler than those in the sun.
Cooling our streets would also mean a significant reduction in energy usage by air conditioners in the home. It’s time for city planners to address the issue of urban heat, and begin implementing strategies to keep things cool in the sweltering months.