In Western Sydney, oppressive heat is part of everyday life when summer rolls around, with temperatures in some suburbs regularly exceeding 40 degrees Celsius.
The sprawling 1,780 hectare Nancy Bird Walton Airport site is located in Badgerys Creek, a suburb that has previously recorded peaks of 50.1C on extreme heat days during summer.
Sebastian Pfautsch, a professor of urban planning at Western Sydney University who has spent years gathering data on the effects of urban heat, is concerned the region's new airport could act as a heat sink making nearby homes even hotter.
A heat sink is a term that refers to a localised area that absorbs lots of solar radiation and then re-radiates it making the environment around it warmer, he explained.
Nearby suburbs, like St Marys, have hit 48.9C, the same temperature that made Penrith the hottest place on Earth on a day in 2020.
Professor Pfautsch said the airport conditions could impede southerly winds for Penrith, which normally produce a cooling effect during extreme heat in the summer.
"Everything we know points towards the airport being a very large heat sink, so we have masses of unshaded black tarmac that, of course, acts like a local island that absorbs heat during the day and makes the air warmer," he said.
