Building climate-resilient cities

Abstract

More than half the world’s population lives in urban areas, and that share will grow to two-thirds by 2050, according to the United Nations. To be safe and sustainable in the face of extreme weather and other climate hazards, cities will have to adapt. Materials technologies, both low tech and cutting edge, will play an important role. Cities must brace against a range of threats, including heat waves baking Southeast Asia, tropical storms and rising seas menacing coastal megacities, wildfires raging in Australia, and rivers bursting with torrential rainfall in the US Midwest. Intense heat, in particular, can melt asphalt roads and buckle railways—and it kills thousands annually. “Heat is the number 1 lethal natural disaster every year,” says Kurt Shickman, executive director of the Global Cool Cities Alliance, based in Washington, DC. “And the poorest feel the worst of the effect.” Scientists and entrepreneurs are developing technologies to design