Tens of thousands of people in Freetown, Sierra Leone, live in informal settlements dense with metal and concrete buildings that trap heat and make heatwaves more dangerous. An experiment has shown that covering such buildings with a cheap mirrored film can substantially reduce the temperature inside.
Since becoming the chief heat officer of Freetown in Sierra Leone, Eugenia Kargbo has experimented with all kinds of ways to protect the city from heat. When a group of researchers …