The Role of the Design of Public Squares and Vegetation Composition on Human Thermal Comfort in Different Seasons a Quantitative Assessment

Abstract

Increasingly, public open spaces are gaining importance for human well-being in dense, urban areas. In inner city locations, squares can provide easy access to greenery and thus encourage social encounters. Microclimatic conditions influence the squares’ attractiveness. However, knowledge is still limited on the impact of different layouts of squares, particularly the impact of the vegetation composition on the human thermal comfort across the seasons in temperate climates. Therefore, our research aims to discern how human thermal comfort is affected by the different elements existing in different open areas of Munich, Germany. For this purpose, five different squares were analyzed on five typical days to create an overview of how human thermal comfort is affected by the layout and vegetation composition during the year. The study areas were selected in view of their size, pavement type, and the number of trees. Micrometeorological simulations were performed using the ENVI-met V 4.6 model to identify how different aspects affect the physiological equivalent temperature (PET) on typical Munich days. The urban morphology was observed to be the greatest factor affecting PET in all the cases studied. Of microclimate variables, the surface temperature was relevant only on warm days. Long-wave radiation, on the other hand, positively affected the PET on cold days. The results suggested that urban morphology has a high impact on the human thermal comfort in urban squares. The results obtained showed that it is necessary to consider diverse vegetation arrangements combined with urban morphology characteristics to optimize human thermal comfort under a range of climatic conditions.

Keywords

• green infrastructure
• urban climate
• outdoor thermal comfort
• microclimate modeling
• ENVI-met