It was 116 degrees Fahrenheit (46.7 degrees Celsius) in the shade outside the new Al Janoub soccer stadium, and the air felt to air-conditioning expert Saud Ghani as if God had pointed “a giant hair dryer” at Qatar. Yet inside the open-air stadium, a cool breeze was blowing. Beneath each of the 40,000 seats, small grates adorned with Arabic-style patterns were pushing out cool air at ankle level. And since cool air sinks, waves of it rolled gently down to the grassy playing field. Vents the size of soccer balls fed more cold air onto the field. Ghani, an engineering professor at Qatar University, designed the system at Al Janoub, one of eight stadiums that the tiny but fabulously rich Qatar must get in shape for the 2022 World Cup. His breakthrough realization […]