Human Biometeorological Assessment of Pedestrian Thermal Stress in Intermodal Transport Spaces: Evidence from Milan and Lisbon

Climate change is intensifying pedestrian heat exposure in urban public spaces, yet intermodal transport nodes remain underexplored from a human biometeorological perspective. This study introduces an exposure-based framework that classifies intermodal sub-spaces by expected pedestrian dwell time (Transitory, Stationary, Adjacent) and by how thermal stress accumulates over time (cumulative and radiative regimes). The framework was applied to Milan Lambrate and Lisbon Rossio using hourly meteorological data (June–September 2025) processed through the RayMan model to compute the Physiologically Equivalent Temperature (PET) and Sky View Factor (SVF) at five points per node. PET exceeded air temperature by 5–10 °C during peak hours, illustrating that air temperature alone does not capture the combined radiative, convective and physiological influences represented by PET. Milan Lambrate displayed a chronic, cumulative regime, exceeding 1200 stress hours per site, while Lisbon Rossio showed a radiative regime of short, intense peaks exceeding 51 °C despite fewer cumulative hours. Comparable SVF values produced markedly different outcomes, showing that sky openness alone cannot explain exposure patterns; obstacle geometry and solar timing were decisive. By linking exposure duration to functional typology, this framework addresses an overlooked determinant of cumulative pedestrian heat burden and offers a transferable basis for climate-responsive design of intermodal transport nodes.