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Author Bierman, A.
Title Will switching to LED outdoor lighting increase sky glow? Type Journal Article
Year 2012 Publication Lighting Research and Technology Abbreviated Journal Lighting Research and Technology
Volume 44 Issue 4 Pages 449-458
Keywords LED; light emitting diode; skyglow; light pollution; modeling; Radiative transfer
Abstract As LED sources are increasingly being used for outdoor lighting, concerns are being raised about their impact on man-made sky glow. This paper compares the amount of light scattered back to Earth from a 6500 K phosphor-converted white LED light source to that from a 2050 K high pressure sodium (HPS) light source. Calculations based solely on molecular Rayleigh scattering provide an upper limit of 22% more scatter from the LED source, but are not realistic because the atmosphere has significant scatter from aerosol content. Adding in the effects of aerosols in the atmosphere, as derived from aerosol optical depth measurements and Mie scattering distributions, reduces the wavelength dependency of scattered light to where the LED source has roughly 10–20% more scattered light contributing to sky glow. Scattering ratios (LED:HPS) are calculated for different angles and atmospheric conditions.
Address Lighting Research Center, 21 Union Street, Troy, NY 12180-3352, USA; bierma2(at)rpi.edu
Corporate Author Thesis
Publisher (up) SAGE Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1477-1535 ISBN Medium
Area Expedition Conference
Notes Luginbuhl, Boley, and Davis (2013) dispute Bierman's thesis. Approved no
Call Number IDA @ john @ Serial 269
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Author Estrada-García, R.; Garcí­a-Gil, M.; Acosta, L.; Bará, S.; Sanchez de Miguel, A.; Zamorano, J.
Title Statistical modelling and satellite monitoring of upward light from public lighting Type Journal Article
Year 2015 Publication Lighting Research and Technology Abbreviated Journal Lighting Res. & Tech.
Volume Issue 1477153515583181 Pages 1-30
Keywords Remote sensing; radiative transfer; modeling; skyglow; light pollution; urban
Abstract In this work, we propose an approach to estimating the amount of light wasted by being sent towards the upper hemisphere from urban areas. This is a source of light pollution. The approach is based on a predictive model that provides the fraction of light directed skywards in terms of a small set of identified explanatory variables that characterise the urban landscape and its light sources. The model, built via the statistical analysis of a wide sample of basic urban scenarios to compute accurately the amount of light wasted at each of them, establishes an optimal linear regression function that relates the fraction of wasted flux to relevant variables like the kind of luminaires, the street fill factor, the street width, the building and luminaire heights and the walls and pavement reflectances. We applied this model to evaluate the changes in emissions produced at two urban nuclei in the Deltebre municipality of Catalonia. The results agree reasonably well with those deduced from the radiance measurements made with the VIIRS instrument onboard the Suomi-NPP Earth orbiting satellite.
Address Escola Tècnica Superior d’Enginyeria Industrial de Barcelona (ETSEIB), Universitat Politècnica de Catalunya, Spain; manuel.garcia.gil(at)upc.edu
Corporate Author Thesis
Publisher (up) Sage Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 1155
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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 Thesis
Publisher (up) SAGE Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1477-0938 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 1225
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Author Rabaza, O.; Aznar-Dols, F.; Mercado-Vargas, M.; Espin-Estrella, A.
Title A new method of measuring and monitoring light pollution in the night sky Type Journal Article
Year 2014 Publication Lighting Research and Technology Abbreviated Journal Lighting Research and Technology
Volume 46 Issue 1 Pages 5-19
Keywords Instrumentation; all-sky; measurement; modeling; monitoring
Abstract This paper describes a method of measuring and monitoring light pollution in the night sky. This method is capable of instantly quantifying the levels of artificial radiance and monochromatic luminance of the sky glow by means of a system that includes an all-sky camera as well as several interference filters. The calibration is done with an integrating sphere where the measurement pattern used is obtained from the light reflected from the inner wall of the sphere which comes from radiation emitted by a calibration lamp with a known luminous flux. The inner wall of this sphere is a Lambertian surface, which ensures that the light reflected or falling on it is uniformly dispersed in all directions (i.e. the surface luminance is isotropic).
Address Ovidio Rabaza Castillo, E.T.S. de Ingenieros de Caminos, Canales y Puertos, Departamento de Ingenieria Civil, Campus de Fuentenueva, Universidad de Granada, 18071, Granada, Spain E-mail: ovidio(at)ugr.es
Corporate Author Thesis
Publisher (up) SAGE Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1477-1535 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 1347
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Author Rea, M. S.; Bierman, A.
Title Spectral considerations for outdoor lighting: Consequences for sky glow Type Journal Article
Year 2014 Publication Lighting Research and Technology Abbreviated Journal Lighting Res. & Tech.
Volume 47 Issue 8 Pages 920-930
Keywords Lighting; skyglow; spectrum; scattering; aerosol; modeling
Abstract It is well known that the magnitude of sky glow on a clear night depends upon the aerosol content in the atmosphere and the spectral power distribution (amount and spectrum). Sources with a greater proportion of short-wavelength radiation produce more backscattered radiation, but as aerosol density increases, the differential effect of spectrum becomes smaller. Sky glow magnitude also depends upon the operating characteristics of the detector and will be greater when the spectrum of the backscattered radiation is tuned to the spectral band-pass characteristics of the detector. The human visual system is most often used to assess sky glow magnitude, but its spectral response is not limited to a single, univariate detector. Rather, the retina is composed of many neural channels, each with its own spectral and absolute sensitivities to optical radiation. Since we can use a different neural channel to see an individual star than we do to gain an overall impression of sky brightness, changes to the spectral power distribution of backscattered radiation differentially, and simultaneously, affect one’s ability to see a single star and to assess sky brightness. A general method for assessing sky glow based upon aerosol content, spectral power distribution and the specific operating characteristics of a detector, human or otherwise, is offered.
Address Lighting Research Center, Rensselaer Polytechnic Institute, Troy, New York, USA
Corporate Author Thesis
Publisher (up) The Society of Light and Lighting Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 1065
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