The influence of urban canyons on thermal comfort:

Abstract

New research regarding the comfort and liveability of modern urban areas has gained increasing attention with climate changes and the trend towards intensified urbanization in modern cities. The urbanization processes have commonly resulted in urban heat islands, dense and central spaces where the air temperature is higher when compared to peripheral areas. The increase in the temperature in these spaces causes thermal discomfort, directly impacting people's quality of life. The urban morphology impacts users' thermal perception while limiting or allowing solar and wind access, thus interfering with the thermal comfort perceived by people. That is the case of urban canyons, a morphologic phenomenon that can reduce the solar incidence and local wind speeds, altering the heat exchanges between buildings and the air and changing the thermal comfort. Thus, through parametric approaches, the present work aims to identify how the changes in the urban morphology impacted the thermal conditions of an urban canyon in the central area of Juiz de Fora, Minas Gerais, Brazil. The analyses, which compared three different moments in history (1940, 1980, and 2020), were performed using Ladybug Suite Tools / Grasshopper plugins for Rhinoceros software; and were based on the Universal Thermal Climate Index (UTCI). The maps generated indicate the changes in the local thermal comfort and its historical development. The results demonstrated that the urbanization process over the years strongly affected the thermal conditions of the urban canyon at the pedestrian level.