Cooling the concrete jungle: How Paris, Singapore, Barcelona, and Dakar are redesigning their cities to survive extreme heat

The urban heat island trap

Dense, high-rise construction turns cities into heat islands where concrete stores warmth and blocks ventilation. Nighttime cooling is limited, and climate change is expected to bring more frequent and intense heatwaves. The current heat rolling over Germany has renewed attention on how municipalities can prepare for extremes.

Paris: 1,400 cool spots and a stress test

Paris has long struggled with narrow streets and limited greenery, but it now offers roughly 1,400 places to cool down, from shaded park benches to public rooms in the city hall that open during heat events. Almost every corner has a free drinking-water fountain, and more and more misting showers are appearing in squares and pathways to provide wet relief. At the national level, France runs a layered heat-protection plan with warning levels, a register for at-risk groups, and repeated public-service tips. A few years ago Paris tested a large-scale simulation in two districts to see how hospitals, fire services, residents, and schools would cope with unusually extreme, prolonged heat. Other cities have since taken notice and plan their own stress tests.

Singapore: greenery and cold from below

The Southeast Asian financial hub is regarded as a pioneer in urban heat resilience. Rather than relying solely on air conditioning, it has pursued massive greening for years: vertical gardens on high-rises, vegetated facades, and rooftop gardens that reduce solar heating and cast shade. New districts are laid out so that air circulates better and heat islands are avoided. In some neighbourhoods entire blocks are cooled by an underground pipe network that pumps ice-cold water to office buildings, replacing many individual air-conditioning units. This saves electricity and cuts the waste heat those units would otherwise release. Light-coloured facades and road surfaces also help store less heat.

Barcelona: superblocks and 500 retreats

In the Spanish tourist hub high humidity can make temperatures above 35°C extremely sweaty. The city now provides around 500 cooling rooms in public buildings such as museums and in pharmacies and drugstores that join voluntarily. Best known are the islands of several blocks, plazas, and traffic-calmed streets that, with abundant greenery, create shady rest areas amid rushing traffic. Currently six such superilles (superblocks) exist, restricting through-traffic and giving pedestrians room to breathe.

Dakar: ancient clay, modern prize

West African countries on the Sahara's rim belong to the hottest on Earth. Architect Francis Kéré, born in Burkina Faso and long resident in Germany, adapts old techniques to contemporary buildings. In 2022 he became the first African to win architecture's top honour, the Pritzker Prize. His Goethe-Institut in Senegal's capital, opened in April, demonstrates how cool places in future hot cities could work. Reddish-brown clay bricks absorb heat and release it slowly. The curved structure orients itself so that its own shadow and cross-ventilation provide much of the cooling. Kéré believes clay architecture can be used on a larger scale.

The examples show that there is no single fix, but a mix of ancient wisdom and modern engineering can make cities safer as temperatures climb.