Landscape Attributes, Microclimate and Thermal Comfort of an Urban Square in Moderate and Dry Climate

Recent rapid urban growth in major cities highlights the role of public squares, where their success can be gauged by its frequency of use and the outdoor thermal conditions. Despite the growing number of studies on outdoor thermal comfort in temperate and dry climate, those done in the Middle East are still limited. This paper examines the effects of landscape attributes on microclimatic conditions and outdoor thermal comfort based on the physiological equivalent temperature (PET) index in Esfahan, Iran. The thermal comfort prediction and correlation between thermal environment and the use of urban space were also explored. Two fieldwork studies were conducted through simultaneous environmental measurement and questionnaire survey in winter and summer at a public square in Esfahan. The obtained data became the basis for Tmrt (mean radiant temperature) and PET estimations, supported by RayMan model. The thermal environment was investigated with different landscape attributes. The derived thermal acceptable range was found to be considerably wider that those reported in previous studies. A strong correlation was confirmed between the thermal conditions and the use of outdoor spaces. The findings demonstrated the strong positive influence of air velocity and evaporative effect of water on thermal comfort. The findings contribute toward suitable design of public squares in climates similar to Esfahan.

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