Influence of Urban Spatial Morphology on Air Temperature Variance

Urban spatial geometric morphology is one of the key factors that results in air temperature variance between urban and suburban sites or at different urban positions. Considering the Adelaide central urban area of South Australia as study area and using urban digital elevation model (DEM) data with a high spatial resolution and field measurement meteorological data, this study estimated the sky view factor (SVF), frontal area index (FAI), and accumulated absorbed solar irradiation (AASI) from the land surface; these parameters were used to discuss the influence of the land surface on air temperature and urban heat island (UHI) under a optimal scale. The results indicate that urban spatial morphological parameters of the visually neighbouring positions display an obvious effect on the spatial-temporal air temperature variance. The degree of influence of AASI on air temperature variance during daytime increases with the solar elevation angle. A difference was noted between the influence of SVF and FAI on the urban heat island at different times in summer and winter, in which the influence of SVF and FAI on nocturnal UHI is more significant, whereas the relationship during daytime is complex.