Albert Gassul,

Director of Public Space Services, Metropolitan Area of Barcelona

Abstract

Cities are warming faster than their surroundings, and the impacts are no longer abstract: longer heatwaves, harsher nights, stressed public health, and public space that becomes unusable precisely when it is needed most. A metropolitan response can turn streets, squares and parks into climate infrastructure, reducing heat exposure while improving everyday urban life. This approach treats sustainability as a project premise. A mandatory sustainability protocol helps translate climate goals into specific, enforceable choices from early concept to construction: shading strategies, soil and vegetation performance and water-sensitive urban design. Cooling results from three complementary levels. First, expanding and connecting green infrastructure to build cooler, more resilient microclimates and to protect biodiversity under rising temperatures. Second, managing rainwater as a resource—capturing, infiltrating, storing and reusing it to support vegetation, reduce runoff and strengthen the urban water cycle. Third, adapting public space to heat risk through comfort-driven design, measurable performance targets and solutions that remain reliable over time. Cooling strategies are core policies for urban quality, public health, equity and resilience, making the metropolis more habitable today while preparing it for the hotter decades ahead.