Urban heat island (UHI) is one of the most important environmental hazards in the city that impact on quality of life. This might prove to be a very unsustainable factor, leading to excessive energy use for cooling and putting urban population at great morbidity and mortality risks and then to unliveable city. UHI is expected to pose increasing challenges for Tehran metropolitan area in the following decades, placing greater stress and impacts on multiple social and biophysical systems, including population health, social comfort, urban infrastructure, energy demand and water supplies. Therefore, we should take an action now to avoid possible serious environmental damage and design our cities to reduce the UHI effects significantly. The focus of this research was on the effects of two factors including vegetation cover and albedo of materials on the intensity of the UHI, through a case study on the Tehran metropolitan area. The original contributions of the research work were development of new model called “Natural Ventilator of the City” (NVC) in the central part of the city to mitigate the effect of UHI and improve the existing condition of life quality and move forward sustainability in Tehran, mapping out UHI by using satellite image, historical weather data and mobile survey, modelling based on GIS analysis (spatial analysis), and finally, simulating the NVC model by ENVI-met, three-dimensional microclimate model. The ENVI-met simulation results, according to 3 scenarios, showed that vegetation cover along with high albedo material can extremely contribute to mitigate the effect of UHI.
Natural Ventilator of the City; Tehran Metropolitan Area; Urban Heat Island;