America’s hottest city is nearly unlivable in summer. Can cooling technologies save it?

Phoenix's new heat tsar' is betting on less asphalt, more green canopy and reflective surfaces to cool the sprawling heat island

A surge in heat-related deaths amid record-breaking summer temperatures offer a glimpse into the future" and a stark warning that one of America's largest cities is already unlivable for some, according to its new heat tsar.

Almost 200 people died from extreme heat in Phoenix in 2020 - the hottest, driest and deadliest summer on record with 53 days topping 110F (43C) compared with a previous high of 33 days. Last year there were fewer scorching days, but the death toll remained staggeringly high, with people experiencing homelessness and addictions dying disproportionately.