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Author Kocifaj, M.; Solano Lamphar, H.A.
Title Skyglow effects in UV and visible spectra: radiative fluxes Type Journal Article
Year 2013 Publication Journal of Environmental Management Abbreviated Journal J Environ Manage
Volume 127 Issue (up) Pages 300-307
Keywords Animals; Darkness; Environmental Exposure/*analysis; *Light; Models, Theoretical; *Ultraviolet Rays; Light pollution; Optical thickness; Public lighting system; Two stream approximation
Abstract Several studies have tried to understand the mechanisms and effects of radiative transfer under different night-sky conditions. However, most of these studies are limited to the various effects of visible spectra. Nevertheless, the invisible parts of the electromagnetic spectrum can pose a more profound threat to nature. One visible threat is from what is popularly termed skyglow. Such skyglow is caused by injudiciously situated or designed artificial night lighting systems which degrade desired sky viewing. Therefore, since lamp emissions are not limited to visible electromagnetic spectra, it is necessary to consider the complete spectrum of such lamps in order to understand the physical behaviour of diffuse radiation at terrain level. In this paper, the downward diffuse radiative flux is computed in a two-stream approximation and obtained ultraviolet spectral radiative fluxes are inter-related with luminous fluxes. Such a method then permits an estimate of ultraviolet radiation if the traditionally measured illuminance on a horizontal plane is available. The utility of such a comparison of two spectral bands is shown, using the different lamp types employed in street lighting. The data demonstrate that it is insufficient to specify lamp type and its visible flux production independently of each other. Also the UV emissions have to be treated by modellers and environmental scientists because some light sources can be fairly important pollutants in the near ultraviolet. Such light sources can affect both the living organisms and ambient environment.
Address ICA, Slovak Academy of Sciences, 9, Dubravska Road, 845 03 Bratislava, Slovak Republic. kocifaj@savba.sk
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0301-4797 ISBN Medium
Area Expedition Conference
Notes PMID:23792881 Approved no
Call Number IDA @ john @ Serial 265
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Author Noll, S.; Kausch, W.; Barden, M.; Jones, A.M.; Szyszka, C.; Kimeswenger, S.; Vinther, J.
Title An atmospheric radiation model for Cerro Paranal: I. The optical spectral range* Type Journal Article
Year 2012 Publication Astronomy & Astrophysics Abbreviated Journal A&A
Volume 543 Issue (up) Pages A92
Keywords atmospheric effects; site testing; radiative transfer; radiation mechanisms: general; scattering; techniques; spectroscopic; modeling; observatories; Cerro Paranal
Abstract Aims. The Earth’s atmosphere affects ground-based astronomical observations. Scattering, absorption, and radiation processes deteriorate the signal-to-noise ratio of the data received. For scheduling astronomical observations it is, therefore, important to accurately estimate the wavelength-dependent effect of the Earth’s atmosphere on the observed flux.

Methods. In order to increase the accuracy of the exposure time calculator of the European Southern Observatory’s (ESO) Very Large Telescope (VLT) at Cerro Paranal, an atmospheric model was developed as part of the Austrian ESO In-Kind contribution. It includes all relevant components, such as scattered moonlight, scattered starlight, zodiacal light, atmospheric thermal radiation and absorption, and non-thermal airglow emission. This paper focuses on atmospheric scattering processes that mostly affect the blue (<0.55&#8201;&#956;m) wavelength regime, and airglow emission lines and continuum that dominate the red (>0.55&#8201;&#956;m) wavelength regime. While the former is mainly investigated by means of radiative transfer models, the intensity and variability of the latter is studied with a sample of 1186 VLT FORS&#8201;1 spectra.

Results. For a set of parameters such as the object altitude angle, Moon-object angular distance, ecliptic latitude, bimonthly period, and solar radio flux, our model predicts atmospheric radiation and transmission at a requested resolution. A comparison of our model with the FORS&#8201;1 spectra and photometric data for the night-sky brightness from the literature, suggest a model accuracy of about 20%. This is a significant improvement with respect to existing predictive atmospheric models for astronomical exposure time calculators.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0004-6361 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 274
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Author Johansson, M.; Pedersen, E.; Maleetipwan-Mattsson, P.; Kuhn, L.; Laike, T.
Title Perceived outdoor lighting quality (POLQ): A lighting assessment tool Type Journal Article
Year 2013 Publication Journal of Environmental Psychology Abbreviated Journal Journal of Environmental Psychology
Volume 39 Issue (up) Pages 14-21
Keywords Perception; Street lighting; Observation-based environmental assessment; Urban space
Abstract A shift towards more energy-efficient light sources for outdoor lighting such as light-emitting diodes (LEDs) is underway. Photometric measures are not sufficient to capture how users experience the light, so complementary tools are required. This study aimed to develop an observer-based environmental assessment tool, based on bipolar semantic differentials, for outdoor lighting in urban spaces. Exploratory (N = 130) and confirmatory (N = 117) factor analyses of observations of lighting installations made by laypersons on-site along pedestrian paths, resulted in two dimensions of high reliability: the Perceived Strength Quality (PSQ, Cronbach's alpha = 0.82–0.85) and the Perceived Comfort Quality (PCQ, Cronbach's alpha = 0.77–0.81). PSQ and PCQ differentiated between light sources of different illuminance level, colour temperature and colour rendering. Regression analyses showed that the perceived lighting qualities helped to explain the variance in visual accessibility, whereas PCQ helped to explain perceived danger in the environment. The perceived lighting qualities can add to the understanding of pedestrians' perception of outdoor lighting, and is proposed as a complementary tool for development of sustainable light designs in the urban environment.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0272-4944 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 279
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Author Figueiro, M.G.; Rea, M.S.
Title The effects of red and blue lights on circadian variations in cortisol, alpha amylase, and melatonin Type Journal Article
Year 2010 Publication International Journal of Endocrinology Abbreviated Journal Int J Endocrinol
Volume 2010 Issue (up) Pages 829351
Keywords blue light; red light; circadian rhythm; cortisol; alpha amylase; melatonin; photobiology; suprachiasmatic nuclei; endocrinology
Abstract The primary purpose of the present study was to expand our understanding of the impact of light exposures on the endocrine and autonomic systems as measured by acute cortisol, alpha amylase, and melatonin responses. We utilized exposures from narrowband long-wavelength (red) and from narrow-band short-wavelength (blue) lights to more precisely understand the role of the suprachiasmatic nuclei (SCN) in these responses. In a within-subjects experimental design, twelve subjects periodically received one-hour corneal exposures of 40 lux from the blue or from the red lights while continuously awake for 27 hours. Results showed-that, as expected, only the blue light reduced nocturnal melatonin. In contrast, both blue and red lights affected cortisol levels and, although less clear, alpha amylase levels as well. The present data bring into question whether the nonvisual pathway mediating nocturnal melatonin suppression is the same as that mediating other responses to light exhibited by the endocrine and the autonomic nervous systems.
Address Lighting Research Center, Rensselaer Polytechnic Institute, 21 Union Street, 3rd Floor, Troy, New York, NY 12180, USA
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1687-8337 ISBN Medium
Area Expedition Conference
Notes PMID:20652045; PMCID:PMC2905913 Approved no
Call Number IDA @ john @ Serial 291
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Author Semeniuk, Kent (ed)
Title Gazing Up: An Exploration of Municipal Night Lighting Practices Amongst Six Canadian Municipalities Type Manuscript
Year 2014 Publication Abbreviated Journal
Volume Issue (up) Pages
Keywords light pollution; public policy; Canada; outdoor lighting; municipal
Abstract Light pollution is broadly defined as the unnecessary illumination of the nocturnal environment. Light pollution is a pervasive phenomena shown to have harmful consequences for both the biotic and abiotic components of an ecosystem. While some municipalities have begun to address the environmental and economic costs of light pollution, most have not. The goal of this study was to investigate current municipal night lighting practices for six selected Canadian municipalities with the aim of determining their policies and practices for night lighting. Semi-structured interviews with key informants were conducted and analyzed using a mixed methods approach that included a thorough literature review. The results indicate that rising energy costs, aging infrastructure and the lighting industry are driving the majority of changes taking place in adapting municipalities while most municipalities remain content with status quo. The research conducted led to guideline improvements for municipal night lighting in today’s municipalities.
Address School of Environmental Design and Rural Development, University of Guelph
Corporate Author Thesis Master's thesis
Publisher University of Guelph Place of Publication Guelph, Ontario Editor Semeniuk, Kent
Language English 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 305
Permanent link to this record