The relationship between height to width ratios and the heat island intensity at 22:00 h for Singapore

The statistical relationship between urban canyon height-to-width (H/W) ratios and nocturnal heat island intensities for public housing estates in Singapore has been examined. Although a number of similar studies have been conducted for temperate cities, this is a first attempt at correlating H/W to heat island intensities for a tropical city. Heat island intensities were examined specifically at 22:00 h because a previous study of Singapore's heat island determined that the heat islands were well developed by that time. A total of 17 Housing Development Board (HDB) estates were studied and at least two vehicle traverses were conducted for each estate on nights with a few days of antecedent dry weather conditions. H/W ratios for each estate were tabulated by proportion of building length. The statistical analysis demonstrates that there is a positive relationship between the heat island intensities and the median H/W, such that ΔTu−r(max)=0.952 (median H/W)−0.021, statistically significant at α=0.05 with a p-value of 0.001 and a correlation coefficient of 0.53. Copyright © 1999 Royal Meteorological Society