A study of subjective human perceptions of the microclimatic and physical conditions at riverside locations

Water surfaces and shaded canopies are important landscaping elements that significantly influence urban thermal environments and subjective perceptions. This study investigated the regulatory effects of microenvironment factors on microclimate and subjective thermal perceptions in riverside areas by field surveys combined with ENVI-met simulations. Field measurements and questionnaires revealed that the neutral temperature in the study was 24.6°C as indicated by the physiologically equivalent temperature (PET), whilst the preferred temperature was slightly lower at 24.2°C. Additionally, satisfaction levels decreased as PET was increased and/or with an increase in distance from the river. A distance of 50 m from the river was most preferred by pedestrians both in open and tree-canopied areas. Furthermore, thermal sensation votes were positively correlated with site openness and distance from the waterbody. Simulation results demonstrated that thermal environments can be moderated by various physical environmental factors, particularly natural elements, which aligns with subjective satisfaction levels. More significant correlations were observed in the afternoon. ENVI-met simulations identified tree canopies as the most effective cooling element amongst the options studied, consistent with people's preferences under extreme conditions. The findings of this study can inform future environmental design and landscaping strategies to enhance thermal comfort in riverside areas.