We designed shade out of our cities. We can design it back in

As I write these words, a heat wave is sweeping through Europe. Last month, a heat wave swept through the East Coast. Next month, a heat wave might sweep through the Middle East, or South Asia, or North Africa. As temperatures continue to reach record highs—and climate change increases the likelihood of heat waves—the sun has become foe, and shade has become king. Shade can lower the ambient temperature of the air by as much as 15 to 20 degrees Fahrenheit. It can cool surfaces by as...