Rethinking cities in the era of climate change

Professor Sascha Roesler, Associate Professor of Urbanisation Theory at the USI Academy of Architecture, took part in the event "Urbane Pioniere: Wie Städte heute Zukunft gestalten". Organised by NZZ Sustainable Switzerland, the event focused on the urban transformations required to tackle the climate, social, and technological challenges of the future.

The encounter brought together experts from various fields to reflect on how cities and territories can adapt to climate change through new urban planning, architectural, and infrastructural strategies. During the debate, international examples of urban transformation were presented—ranging from Singapore to Hamburg and Copenhagen—with a particular focus on managing urban heat, sustainable mobility, and the quality of public spaces.

Speaking at the event and in a follow-up interview, Sascha Roesler highlighted that Switzerland is also progressively entering a new climate phase. "We are observing that many regions in Central Europe, including Switzerland, are gradually entering a more subtropical climate zone," the professor explained, emphasising that Swiss cities have historically been designed primarily to cope with the cold, rather than increasingly frequent heatwaves.

According to Roesler, climate change now demands a profound revision of how urban spaces are conceived. "We need to start designing outdoor spaces climatically as well," he stated, insisting on the necessity of thinking about indoor and outdoor environments together, including shading, ventilation, vegetation, and the management of urban surfaces. Streets, squares, and courtyards should no longer be viewed as mere residual spaces between buildings, but as genuine "designed microclimates."

Among the most effective measures highlighted by the professor are planting trees, reducing asphalted surfaces, introducing water into public spaces, and increasing green areas on roofs and facades. "A single large tree can reduce the perceived temperature by several degrees," Roesler noted, pointing out how materials and urban layouts directly impact quality of life during heatwaves.

The professor also recalled the concept of "Thermal Governance"—an integrated approach to urban climate regulation that involves architecture, urban planning, and regulatory tools. International examples cited included Paris, with its greening and urban unpaving initiatives, and Singapore, where vertical vegetation and green infrastructure are now fully integrated into building design.

Alongside Professor Sascha Roesler, the event featured architect Roger Boltshauser, futurist Oona Horx Strathern, and Monika Litscher, Director of the Union of Swiss Cities. The discussion was moderated by climate policy journalist Kalina Oroschakoff.