Incorporating urban thermal comfort into transit-oriented development (TOD) planning: Non-linear heterogeneous built environment effects

Transit-Oriented Development (TOD) has been widely promoted as a planning framework aimed at reducing automobile dependence and mitigating urban sprawl by encouraging the use of public transit and active travel. However, the increasing frequency of record-breaking heat events may undermine the pedestrian and cycling-friendly conditions that TOD seeks to promote. In addition, some of TOD’s core principles, such as high density and compact urban form, have been identified as contributing factors to the urban heat island effect. This raises concerns about whether these principles may conflict with other TOD goals such as walkability and people-oriented urban design. These issues highlight the urgent need to incorporate heat mitigation strategies into TOD planning. This study evaluates outdoor thermal comfort during the summer in Shanghai and analyzes the nonlinear and spatially heterogeneous effects of TOD structural factors on thermal conditions. Using the Geospatial Explainable AI (GeoXAI) framework, which enhances model interpretability and accounts for spatial variation, we find that traditional TOD indicators such as population density and building density are positively associated with elevated thermal discomfort. By reconstructing the Design dimension of the TOD evaluation framework, we identify that metro catchment areas with greater variation in building height, higher vegetation ratio, and increased sky view factor are associated with improved thermal comfort. By assessing thermal conditions at the station level and exploring the potential of TOD design to reduce heat stress, this study provides recommendations for integrating thermal mitigation strategies into urban planning and transit-oriented development practices.