Urban Heat Island Studies with emphasis on urban pavements: A review

Increase in urban population across the globe has resulted in drastic rise in anthropogenic activities and urban surface modifications. These contribute to the hike of urban temperature above the temperature of surrounding rural areas. When this happens, the city is said to experience Urban Heat Island (UHI). This paper presents a review of available literatures on the subject matter of UHI with peculiar emphasis on urban pavements. Information on the state of the art of UHI measurement, evaluation, and mitigation is reported. The causes, effects, and spatio-temporal variations in UHI events were studied and discussed. Addressing the harmful effects of UHI would involve adoption of effective mitigation strategies that can improve the environmental, societal, and economic sustainability of urban structures and landscapes. Implementation of innovative designs of urban pavements to ensure lower surface temperature was generally recommended. The use of vegetative covers, reflective surfaces, water retaining materials, and heat capturing devices were found to be effective. The facts presented in this paper are very expedient to inform policy making and guide to future studies that can lead to more innovative engineering designs of sustainable urban pavements for UHI mitigation.