![]() ![]() The difference between this value and the background rural temperature defines the “UHI intensity” ( Δ □ □ − □). In metropolitan areas, the urban core shows a final “peak” in the UHI where the urban maximum temperature is found. Generalized cross-section of a typical UHI. In Figure 1, the uniformity of the “plateau” is interrupted by the influence of distinct intraurban land-uses such as parks, lakes, and open areas (cool), and commercial, industrial or dense building areas (warm). As seen in Figure 1, Oke stated that in a larger city with a cloudless sky and light winds just after sunset, the boundary between the rural and the urban areas exhibits a steep temperature gradient to the UHI, and then the rest of the urban area appears as a “plateau” of warm air with a steady but weaker horizontal gradient of increasing temperature towards the city centre. ![]() Therefore, UHI morphology is greatly influenced by the unique character of each city and its land uses. ![]() The exact form and size of this phenomenon varies in time and space as a result of meteorological, regional, and urban characteristics. ![]() The heat that is absorbed during the day by the buildings, roads, and other constructions in an urban area is re-emitted after sunset, creating high-temperature differences between urban and rural areas. A UHI is best visualised as a dome of stagnant warm air over the heavily built-up areas of cities. The majority of cities are sources of heat and pollution, and the thermal structure of the atmosphere above them is affected by the “heat island” effect. For energy saving, therefore, this paper suggests some strategies to provide the best possible energy saving solution. Then, according to the Oke’s energy balance conceptual model, all of the energy which is absorbed by the surface through radiation or from anthropogenic heat goes somewhere and warms the air above the surface, it is evaporated away with moisture or is stored in the material as heat. Thus, this paper investigates the anthropogenic heat factors that produce the UHI and result in the use of significantly increased use of energy. Thus, this proves to be an unsustainable factor that leads to excessive energy use for cooling and places the urban population at greater risk of increased morbidity and mortality.Īccording to the above perspective and considering that rapid and huge population growth is expected in the near future, it becomes increasingly important to apply UHI mitigation strategies in order to reduce energy consumption and improve the quality of life with focusing on energy consumption. A UHI is a climatic phenomenon in which urban areas have higher air temperature than their rural surroundings as a result of anthropogenic modifications of land surfaces, significant energy use, and its consequent generation of waste heat. With the concentration of anthropogenic activities into urban areas, a climatic environmental problem, the “urban heat island” (UHI), has emerged. Moreover, discomfort and inconvenience to the urban population due to high temperatures, wind tunnel effects in streets, and unusual wind turbulence due to the incorrect use of energy. It is clear that buildings not designed for high climatic quality use more energy for air conditioning and more electricity for lighting. The urban built environment itself is related to global changes in the increase of urban temperatures, the rate of energy consumption, the increased use of raw materials, pollution, and the production of waste, conversion of agricultural to developed land, loss of biodiversity, and water shortages. It will be concluded by making the three important strategies to minimise the impact of UHI on energy consumption: landscaping, using albedo materials on external surfaces of buildings and urban areas, and promoting natural ventilation. It then discusses how these two factors can be affected and gives implication to the city and then focuses on whether actions should be taken for balancing adaptation and mitigation of UHI effects. It explores literally the conceptual framework of confliction between anthropogenic heat and urban structure, which produced UHI intensity and affected energy consumption balance. This paper investigates the impact of anthropogenic heat on formation of urban heat island (UHI) and also determines which factors can directly affect energy use in the city. ![]()
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