Essay On Urban Heat Island

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Large cities commonly create their own climate and weather this weather that they create is known as the ‘urban climate dome’, within which the weather is different from the surrounding rural areas. In a large city the dome can extend 250-300m and its influence may continue tens of kilometres downwind. Cities which have different climates are referred to as urban heat islands. An urban heat island (UHI) is a metropolitan area that is significantly warmer than its surrounding rural areas due to human activities. There is evidence to suggest that the large cities do have urban heat islands and there are many reasons as to why the urban heat islands occur. For example the building materials used to construct cities such as bricks, concrete have high heat capacities and an ability to conduct heat. The buildings and roads that are made from these materials release the heat at night and therefore the city temperature is higher than the surrounding areas temperature. In addition to this the vertical walls and roofs of buildings increase the area exposed at the surface, further enhancing the absorption and storage of heat. In urban areas there is also air pollution…show more content…
It is also better developed in winter when there is a bigger impact from city heating systems; however Urban Heat Islands are not constant due to the distribution of urban structures and the concentration of traffic. The edge of an urban heat island is well defined and temperatures change abruptly at the rural-urban boundary layers. The temperature rises from the edge at a rate of roughly 2 to 4 degrees Celsius per km to the peak in the city with the highest building density. In London on hot days the temperatures in buildings and on public transport can reach 30 degrees and can become unbearable for workers and commuters
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