What controls the magnitude of the daytime heat sink in a desert city?

Nassar, Ahmed K. and Blackburn, G. Alan and Whyatt, J. Duncan (2017) What controls the magnitude of the daytime heat sink in a desert city? Applied Geography, 80. pp. 1-14. ISSN 0143-6228

[img]
Preview
PDF (Manuscript_Revised)
Manuscript_Revised.pdf - Accepted Version

Download (2MB)

Abstract

Abstract The aim of this study was to increase knowledge of the causes of cooling in desert cities. We used a time-series of Landsat images to characterize the changes in daytime land surface temperature during the period of rapid urbanization in Dubai. Changes in land cover and albedo were also quantified from Landsat data and the development of different land use types and variations in urban geometry were characterized. The results demonstrate that urban growth has promoted a heat sink and that all urban land use types contributed to this effect. Vegetation generated the largest cooling effect per unit surface area but impervious surfaces dominated the urban environment and are responsible for the majority of the heat sink created by the city. Changes in albedo were not causally related to the urban heat sink, however, variations in urban geometry, particularly the amount of shading cast by buildings, had some influence on the magnitude of cooling. This study provides evidence that the expansion of the heat sink during urbanization in a desert environment is influenced by the forms of land cover transition, the type of urban land use that is developed, the thermal properties of construction materials used and the geometry of the city environment that is constructed. Future research should concentrate upon understanding these mechanisms in order to plan future developments which maximize cooling and reduce the environmental impacts of desert cities.

Item Type:
Journal Article
Journal or Publication Title:
Applied Geography
Uncontrolled Keywords:
/dk/atira/pure/subjectarea/asjc/3300/3305
Subjects:
ID Code:
84116
Deposited By:
Deposited On:
27 Jan 2017 09:32
Refereed?:
Yes
Published?:
Published
Last Modified:
11 Jul 2020 06:30