Designing for Heat Waves

Cities heat up faster than rural areas because of heat shields and as global temperatures rise cities must design to mitigate heat waves. "The build-up of heat-trapping greenhouses in the Earth’s atmosphere vastly increases the chances of heat waves, and they are becoming more frequent, more intense, longer, and deadlier," reports Bob Berwyn in Pacific Standard.

The problem of cooling down hot cities is not new and some strategies can still apply. "Since the Middle Ages, and perhaps longer, central squares with fountains and trees have served as urban cooling shelters on hot summer days, and, at the Delft University of Technology, Anna Solcerova is quantifying that cooling effect and studying how modern cities can use water to reduce the effects of extreme heat," Berwyn reports. Rain water or gray water sprinkled on the ground can have a big impact on temperatures. "On hot days, just one liter of water applied over three square meters can cool the air by about two degrees Celsius at head height, and by three degrees Celsius at ground level," Berwyn writes.