Nature Climate Change, Published online: 21 April 2025; doi:10.1038/s41558-025-02310-4
Urban heat islands are known to increase heat-related mortality, but a global analysis of more than 3,000 cities reveals that urban heat islands also substantially reduce cold-related mortality — a more than fourfold offset, globally. Although commonly used cooling strategies benefit some tropical cities, they harm others at higher latitudes, and instead a seasonally adaptive approach to heat mitigation is needed.