Effect of Vegetation Cover on Energy Consumption Optimization due to Reduction of Urban Heat Island intensity: Case of Tehran Metropolitan Area

Urbanization through rapid constructions, is the main cause of high heat absorption in urban centers. In addition, the accumulation of heat energy resulted by removal of vegetation cover, has contributed to formation of urban heat islands (UHIs). The spatial distribution of heat intensity in Tehran Metropolitan Area was studied, and the influence of land use and green cover were analyzed in the present work. Data from a variety of sources is used to investigate the impact of greenspaces, on spatial patterns of land surface temperature pockets within the city. Land surface temperature (LST) data is derived from Landsat 8 satellite OLI/TIR sensors, and vegetation cover was extracted by using NDVI method and subsequently examined with the distribution of LST. The study revealed some heat and cool pockets within the city limit. Land surface temperature differences between land use classes were in the range of 5.5-6 °C. Land use and green cover play a critical role and influences microclimate. Green cover has a significant negative correlation with the measured temperature. The mitigation effect of the cool roof and green vegetation at the city scale is discussed and it is concluded that the city-scale deployment of cool roofs and green vegetation can greatly reduce the near-surface air temperature and surface skin temperature. Remedial measures can be taken in future urban planning endeavors based on the results of this study. Thus, the study urges city administrations, policy makers, and architects to take up effective mitigation and adaptation strategies to reduce UHIs effects.