Study on correlation between shadow patterns and human behaviour in hot, arid cities: a case study of Biskra, Algeria

Although the thermal comfort benefits of shade in warm areas are well known, empirical work on the link between public space use and shade pattern from hot, arid cities remain poorly investigated. The aim of the present study is to investigate the correlation between shadow pattern, outdoor thermal comfort and human behaviour, according to the intensity of public space use by urban dwellers. This work was conducted in an urban area in Biskra City (Algeria), characterized by a hot climate, with an average high temperature 40.2 degrees C in summer. In situ investigation and behavioural method were applied for behaviour evaluation. Modelling of shadow pattern and assessment of outdoor comfort utilised the physiological equivalent temperature (PET) index and predicted mean vote (PMV). The findings show that the presence of shadow contributes to low PET; as a result, the PET is closely related to shadow in spring than summer while the distribution of people was significantly affected by shadow in summer than spring which affects the city's liveability. Our findings shed the light on the importance of shadow generated by the built environment to enhance comfort and urban liveability in hot and arid cities.