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rban heat island is the term used to describe metropolitan areas with significantly higher temperatures than its surrounding areas due to the effects of human activities. The main cause of this is the modifications of the environment, particularly land surfaces which store shortwave radiation. Heat is also generated by other means for instance vehicles, air conditioning coolers. The area is usually hotter than surrounding areas. The urban heat island causes environmental impacts such as an increased run off rate- thereby increasing the risk of floods; increase in pollutants like dust, smoke, ozone; a decrease in water vapor in the atmosphere because there is a reduction of plants. Furthermore it impacts on the microclimate of the area, hotter than the surrounding areas during the day and warmer at night.

          This is a phenomena occurring in both developed and developing cities. However the developed cities face more severe consequences as they span a larger area than the smaller developing cities. The more harsh consequences is smog which is a mixture of fog and smoke which traps other pollutants like dust particles and ‘hangs’ over urban areas. It is very toxic to humans and can result in sickness, shortened lifespan and death.

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