How cities can respond to extreme heat

The best thing that has happened in Phoenix, Arizona, since the beginning of July is that the electricity grid has kept functioning. This has meant that during a record-breaking run of daily maximum temperatures above 43°C (110°F), still in progress as The Economist went to press, the houses, indoor workplaces and publicly accessible “cooling stations” in the city have been air-conditioned. There have been deaths from heat stroke and there will be more; there has been a lot of suffering; and there will have been real economic losses. But if Arizona’s grid had gone out, according to an academic quoted in “The Heat Will Kill You First”, a new book, America would have seen “the Hurricane Katrina of extreme heat”.