Fifteen Million People and a Brief to Cool Them Down

Dhaka is among the fastest-warming megacities in the world, thickening with concrete while losing the water bodies and trees that used to moderate it, and in May 2023 Dhaka North City Corporation appointed Bushra Afreen as chief heat officer — the first such appointment in Asia. The role is coordination rather than construction: extreme heat touches buildings, traffic, water supply and waste at once, and nobody in a city government owns it by default. Afreen's brief covers heat-risk awareness, a heat categorisation and warning system for the corporation's roughly 15 million residents, and cooling measures including tree planting, cool pavements and reflective roofs, with explicit priority on informal settlements, migrants and women and girls — the groups who cannot leave the heat and whose homes are built of the materials that trap it. She has been blunt that the harder problem is retrofitting the buildings that already exist rather than designing better new ones.