Record |
Author |
Solano Lamphar, H.A.; Kocifaj, M. |
Title |
Urban night-sky luminance due to different cloud types: A numerical experiment |
Type |
Journal Article |
Year |
2015 |
Publication |
Lighting Research and Technology |
Abbreviated Journal |
Lighting Res. & Tech. |
Volume |
48 |
Issue  |
8 |
Pages |
1017-1033 |
Keywords |
Skyglow; modeling; urban; clouds; radiative transfer |
Abstract |
In this paper, we analyse theoretically and numerically the sky glow in urban and suburban areas, focusing on the zenith-normalised luminance of a cloudy sky. The results suggest that the altitude of a cloud imposes important changes in the luminance distribution. Peak values of sky luminance can be observed at a distance d = R + h tan (z), where R is the city radius, and h is the cloud altitude. Fluctuations of the zenith-normalised luminance over the city are dictated by three effects, specifically (i) extinction and backscatter in the undercloud atmosphere, (ii) the cloud properties and (iii) the radiant intensity function of the dominant ground-based light sources. For high clouds, the aerosol optical property is evident at moderate elevation angles. The light beams emitted from different parts of the city propagate along different inclined trajectories before they contribute to the elevated zenith luminance of low clouds. Then, multiple factors combine together to form the light field at the ground, city-size and city emission pattern being of specific importance. |
Address |
Cátedras CONACYT, Instituto de investigaciones Dr José María Luis Mora, Programa Interdisciplinario de Estudios Metropolitanos (CentroMet), Plaza Valentín Gómez Farías #12 Col. San Juan Mixcoac, México D.F. C.P 03730. E-mail: lamphar(at)gmail.com |
Corporate Author |
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Thesis |
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Publisher |
SAGE |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
English |
Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1477-0938 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
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Approved |
no |
Call Number |
IDA @ john @ |
Serial |
1225 |
Permanent link to this record |