Identification of the Potential Thermal Resilience of Poland’s Most Populous Cities Using the Local Climate Zone Framework

The increasing severity of heat waves in cities requires the integration of spatial morphology with temperature-resilient design; however, comparisons of multi-city systems are scarce. The aim of this article is to assess the potential thermal resilience of Poland’s largest cities, taking into account local climate zones (LCZs), which aligns with the framework of sustainable urban development. The use of LCZs allows for a comparison of the resilience of cities without being influenced by their historical development, providing a diagnostic basis for climate adaptation. The proposed potential thermal resilience index (Rc) integrates exposure, sensitivity, and adaptive capacity, serving as the operational inverse of structural vulnerability to heat (urban heat vulnerability). The results indicate that 62.5% of the cities are characterized by moderate potential thermal resilience; 31.3% of cities have low resilience, and only 6.2% of cities have high resilience. High potential thermal resilience is associated with a large proportion of LCZs A, B, and D, as well as a reduction in both high-density and low-density development, which provides practical guidance for land-use planning. The index shows geographical variation—higher values were found in southern and southwestern Poland. The results suggest the need to correlate physical interventions with social vulnerability and the macroclimate when designing blue-green infrastructure as a key element of sustainable adaptation.