Journal
BOUNDARY-LAYER METEOROLOGY
Volume 142, Issue 2, Pages 305-328Publisher
SPRINGER
DOI: 10.1007/s10546-011-9679-0
Keywords
Multilayer radiation scheme; Radiation; Radiative equilibrium; Radiosity method; Urban surface warming; Urban warming
Categories
Funding
- Ministry of the Environment, Japan [S-5-3]
- Japan Society for the Promotion of Science [22340141]
- Grants-in-Aid for Scientific Research [22340141] Funding Source: KAKEN
Ask authors/readers for more resources
To investigate how a three-dimensional structure such as an urban canyon can affect urban surface warming, we developed an urban multilayer radiation scheme. The complete consideration of multiple scattering of shortwave and longwave radiation using the radiosity method is an important feature of the present scheme. A brief description of this scheme is presented, followed by evaluations that compare its results with observations of the effective albedo and radiative temperature for urban blocks. Next, we calculate the urban surface warming potential (USWP), defined as the difference between the daily mean radiative temperature of urban surfaces (which are assumed to be black bodies), including their canyon effects and the daily mean temperature of a flat surface with the same material properties, under a radiative equilibrium state. Assuming standard material properties (albedo and emissivity of 0.4 and 0.9, respectively), we studied the sensitivity of the USWP to various aspect ratios of building heights to road widths. The results show that the temporally-averaged surface temperature of an urban area can be higher than that of a flat surface. In addition, we determined the overestimation of the effective temperature of urban surfaces induced by the overestimation of the radiation distribution to the walls when one uses a single-layer scheme for urban block arrays that have a low sky-view factor less than around 0.5.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available