Urban heat

What is urban heat?

Average temperatures in large cities are 1 °C to 3 °C higher than in rural areas, as urban areas tend to trap more heat than natural environments. These higher temperatures can have a negative effect on human health and wellbeing, economic productivity, the environment, and infrastructure and services.

Some urban communities are more vulnerable to higher temperatures because of the ‘urban heat island’ effect. The western suburbs of Greater Sydney are particularly vulnerable to the urban heat island effect – temperatures in this region are sometimes 10 °C higher than in eastern Sydney on days of extreme heat.

What is an urban heat island?

Urban heat islands happen when an area has hard, sealed surfaces and less green infrastructure (such as tree canopy, vegetation, and waterways). This is because hard surfaces absorb, store and radiate heat, while green infrastructure reflects heat, provides shade, and releases water into the atmosphere. Green infrastructure also makes local areas easier to enjoy and encourages people to spend time outdoors. It also provides habitat for animals and plants and increases their variety in cities.

While climate change is increasing average temperatures across NSW, urban heat and the urban heat island effect are increasing the heat-related effects of climate change in urban areas. This makes increased temperatures and extreme hot weather events more severe and difficult to manage.

Planning how we will use land plays an important role in reducing urban heat vulnerability. It helps create places and communities that are more liveable and resilient to a changing climate. We are committed to delivering several planning initiatives aimed at reducing urban heat.