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Author Bará, S.; Nievas, M.; Sanchez de Miguel, A.; Zamorano, J.
Title Zernike analysis of all-sky night brightness maps Type Journal Article
Year 2014 Publication Applied Optics Abbreviated Journal Appl Opt
Volume 53 Issue 12 Pages 2677-2686
Keywords modeling; light at night; light pollution; all-sky; Zernike polynomials; image decomposition; sky brightness
Abstract All-sky night brightness maps (calibrated images of the night sky with hemispherical field-of-view (FOV) taken at standard photometric bands) provide useful data to assess the light pollution levels at any ground site. We show that these maps can be efficiently described and analyzed using Zernike circle polynomials. The relevant image information can be compressed into a low-dimensional coefficients vector, giving an analytical expression for the sky brightness and alleviating the effects of noise. Moreover, the Zernike expansions allow us to quantify in a straightforward way the average and zenithal sky brightness and its variation across the FOV, providing a convenient framework to study the time course of these magnitudes. We apply this framework to analyze the results of a one-year campaign of night sky brightness measurements made at the UCM observatory in Madrid.
Address Área de Óptica, Dept. de Física Aplicada, Fac. de Física, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Galicia, Spain
Corporate Author Thesis
Publisher Optical Society of America Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-6935 ISBN Medium
Area Expedition Conference
Notes (down) PMID:24787595 Approved no
Call Number IDA @ john @ Serial 318
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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 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 (down) Luginbuhl, Boley, and Davis (2013) dispute Bierman's thesis. Approved no
Call Number IDA @ john @ Serial 269
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Author Troy, J.R.; Holmes, N.D.; Green, M.C.
Title Modeling artificial light viewed by fledgling seabirds Type Journal Article
Year 2011 Publication Ecosphere Abbreviated Journal Ecosphere
Volume 2 Issue 10 Pages art109
Keywords artificial light; fallout; Hydrobatidae; modeling; Newell's Shearwater; Procellariidae; Puffinus newelli; birds
Abstract Artificial light is increasing in coverage across the surface of our planet, impacting the behavioral ecology of many organisms. Attraction to sources of artificial light is a significant threat to certain fledgling shearwaters, petrels (Procellariidae), and storm-petrels (Hydrobatidae) on their first nocturnal flights to the sea. Disorientation by light can cause these birds to crash into vegetation or manmade structures, potentially resulting in death from physical injury, starvation, dehydration, predation by introduced predators, or collisions with vehicles. We developed a GIS-based method to model the intensity of artificial light that fledgling procellariids and hydrobatids could view en route to the ocean (to estimate the degree of threat that artificial light poses to these birds) and present two models for the island of Kauai as examples. These models are particularly relevant to the federally threatened Newell's Shearwater, or `A`o (Puffinus newelli), of which >30,000 fledglings have been collected in response to disorientation by lights on Kauai during the past 30 years. Our models suggest that there are few to no portions of Kauai from which young birds could fledge and not view light on their post-natal nocturnal flights, which is concerning given evidence of a Newell's Shearwater population decline. In future work using this technique, night light intensity layers could be altered to model the effects of modified coastal light conditions on known and potential procellariid and hydrobatid breeding locations. Furthermore, certain methods presented herein may be applicable to other seabirds and additional taxa in which attraction to anthropogenic light poses a serious threat, including migratory passerines and hatchling marine turtles. Components of this modeling approach could potentially be used to spatially estimate effects of other point-source threats to ecological systems, including sound and air pollution.
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 2150-8925 ISBN Medium
Area Expedition Conference
Notes (down) Approved no
Call Number IDA @ john @ Serial 60
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Author Cinzano, P.; Falchi, F.; Elvidge, C.D.
Title Naked-eye star visibility and limiting magnitude mapped from DMSP-OLS satellite data Type Journal Article
Year 2001 Publication Monthly Notices of the Royal Astronomical Society Abbreviated Journal Monthly Notices of the Royal Astronomical Society
Volume 323 Issue 1 Pages 34-46
Keywords light at night; remote sensing; GTOPO30; DMSP; light pollution; modeling; mapping
Abstract We extend the method introduced by Cinzano et al. (2000a) to map the artificial sky brightness in large territories from DMSP satellite data, in order to map the naked eye star visibility and telescopic limiting magnitudes. For these purposes we take into account the altitude of each land area from GTOPO30 world elevation data, the natural sky brightness in the chosen sky direction, based on Garstang modelling, the eye capability with naked eye or a telescope, based on the Schaefer (1990) and Garstang (2000b) approach, and the stellar extinction in the visual photometric band. For near zenith sky directions we also take into account screening by terrain elevation. Maps of naked eye star visibility and telescopic limiting magnitudes are useful to quantify the capability of the population to perceive our Universe, to evaluate the future evolution, to make cross correlations with statistical parameters and to recognize areas where astronomical observations or popularisation can still acceptably be made. We present, as an application, maps of naked eye star visibility and total sky brightness in V band in Europe at the zenith with a resolution of approximately 1 km.
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 0035-8711 ISBN Medium
Area Expedition Conference
Notes (down) Approved no
Call Number IDA @ john @ Serial 175
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Author Kolláth, Z.
Title Measuring and modelling light pollution at the Zselic Starry Sky Park Type Journal Article
Year 2010 Publication Journal of Physics: Conference Series Abbreviated Journal J. Phys.: Conf. Ser.
Volume 218 Issue Pages 012001
Keywords Skyglow; modeling; measurement; SQM; sky brightness; Zselic; International Dark Sky Park; Hungry; measurements; modeling; light pollution; skyglow; radiative transfer
Abstract One of the first 'International Dark-sky Parks' in Europe was established at the Zselic Landscape Protection Area in Hungary. A special monitoring program has been carrying on to survey the quality of the night sky using 'Sky Quality Meters' and DSLR cameras. The main conclusion of our measurements is that the local villages have only a minimal effect on the quality of the sky. There are light-domes due to the neighbouring cities only close to the horizon, the main source of obtrusive light is the city of Kaposvár. The anthropogenic component of zenith luminance of the night sky is obtained as the function of the distance from the city centre of Kaposvár. Our data were modelled by radiation transfer calculations. These results can help to draw attention to the energy emitted useless to the space and to protect our nocturnal landscape of nature parks for the next generations.
Address Konkoly Observatory, Konkoly Thege u. 15-17, H-1121 Budapest, Hungary; kollath(at)konkoly.hu
Corporate Author Thesis
Publisher IOP Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1742-6596 ISBN Medium
Area Expedition Conference
Notes (down) Approved no
Call Number IDA @ john @ Serial 1436
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