The role of sky view factor and urban street greenery in human thermal comfort and heat stress in a desert climate.

The aim of this study was to understand the effect of urban street greenery type and arrangements on thermal comfort and heat stress in summer. Field measurements and computer simulations were carried out on East-West (E-W) and North-South (N-S) oriented streets in Isfahan, Iran. Through the field measurements in July 2014, 17 different streets were studied, followed by 15 perturbation scenarios (urban design alternatives) simulated by ENVI-met. The study showed that there is a significant and positive relationship between the Sky View Factor (SVF) and the Physiological Equivalent Temperature (PET) values. Comparison of the meteorological parameters within different street orientations showed that the effect of the SVF on the E-W streets was more significant than in N-S streets. Furthermore, greenery arrangement and building heights showed different impacts on the outdoor thermal comfort streets with different orientations. • The effect of different street greenery arrangements on thermal comfort was studied. • A significant positive relationship between SVF and PET was observed. • SVF of more than 0.6 leads to higher heat stress. • The effect of the SVF on the microclimate of E-W streets was more N-S. [ABSTRACT FROM AUTHOR]