![]() However, most of these studies were qualitative examinations of possible thermal effects of urban traffic in relation to urban road network and traffic density distribution. Some studies have explored the effect of urban transport and road traffic on the UHI 12, 13, 14. Anthropogenic heat discharge in a large city can create a heat island of up to 2–3 ☌ both during the day and at night 9, 11. Previous studies suggested that the anthropogenic heat has smaller effect than the land surface modification in albedo and vegetation cover and is negligible in commercial and residential areas. There are two types of anthropogenic heat sources: stationary source from buildings, industries, and public infrastructure, and mobile source from automobiles. Urban population and industries consume large quantity of fossil fuels for heating and cooling buildings, lighting streets and buildings, manufacturing goods and services, and transporting people and goods. Anthropogenic heat discharge in urban areas 9, 10 represents the other major heat component contributing to the formation of UHI. asphalt, concrete, tar and gravel pavements) with low albedo and high heat storage capacity absorbs and accumulates much more of solar radiation 8. The proliferation of artificial urban construction materials (e.g. The urbanization process modifies the land surface from natural rural landscape to artificial urban built-up fabric and substantially alters the energy balance and local climate. The urban thermal environment is determined by the surface and atmosphere energy balance in urban areas 7, 8. UHI effect has been recognized as one of the key indicators of environmental change and global climate change 6. The UHI effect greatly boosts energy consumption in cooling, accelerates air pollution in the form of urban smog, surface dioxide and greenhouse gas emissions, and contributes to global warming 1, 5. ![]() High temperatures in urban areas exacerbate thermal discomfort of city dwellers and increase human health risks (e.g., respiratory illnesses, cardiovascular mortality) 4. The most apparent expression of the impact of urbanization on the environment is the Urban Heat Island (UHI) effect 2, which refers to the phenomenon where the urban areas have a temperature considerably higher than the surrounding rural areas 3. Cities only cover about 1% of the Earth’s surface, but they disproportionally consume about 78% of the world’s energy and produce more than 60% of all CO 2 emissions 1. In conjunction with the agglomerations of population and economic activities, urban traffic has increased rapidly to meet the needs for mobility and accessibility to different parts of the urban areas. Urbanization has been taking place at an unprecedented pace around the world in the past decades.
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