AN ANALYSIS OF THE TEMPERATURE PROFILE OF URBAN STREET CANYON

Abstract

As urbanization progresses, increases in urban cities temperatures are also recorded. The replacement of green spaces with asphalt and concrete has brought about a phenomenon called the Urban Heat Island, commonly called the UHI effect, which describes the trend of increasing ambient temperatures. Since the realization more than a century ago, researchers have been actively doing studies on the various influences of the UHI effect and the possible ways of mitigating the impact. The purpose of this study is to investigate the cooling effect of greenery by analyzing the temperature profile of urban street canyons. Results obtained from field measurements would be compared and the factors which affect the ambient temperatures of the canyons would be discussed. Cross comparison of the climatic conditions between areas would also be done to examine any differences between the micro-climate of different types of development. Field measurements were carried out to collect information about the weather conditions, mainly in terms of air temperature and solar radiation, at all the observation sites to construct the temperature profile of each individual site. The chosen sites for observation are three areas in the Buona Vista One-North Development: Ayer Rajah Industrial Estate, Biopolis and Rochester Park, each representing a different type of development. The weather variables were measured over a period of approximately two months from 1st November 2007 to 26th December 2007 at 26 pre-determined sites along three canyons, one canyon in each site. It was found that temperature difference is mainly attributed to the density of surrounding vegetation, shading and sky view factor. It was also discovered that vegetation brings about a disparity between the micro-climate of these three sites.