Extreme heat events are getting more frequent and more intense. Globally, heat kills more people than any other natural disaster. In fact, nine of the ten deadliest heat waves in human history have occurred since 2000 alone. And vulnerable people tend to live in areas where temperatures are rising the fastest. In 2017, about 157Can white, reflective roofs help cool the world’s increasingly warming cities?
Scientists have long known that cities tend to be hotter than rural areas, partly because of waste heat from cars and air-conditioners and partly because concrete buildings and asphalt roads absorb heat. The resulting urban heat island effect can raise local temperatures by two to five degrees Fahrenheit on average. According to the U.S. Environmental