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Author Kocifaj, M.; Wallner, S.; Solano-Lamphar, H.A. url  doi
openurl 
  Title An asymptotic formula for skyglow modelling over a large territory Type Journal Article
  Year 2019 Publication Monthly Notices of the Royal Astronomical Society Abbreviated Journal  
  Volume (down) 485 Issue 2 Pages 2214-2224  
  Keywords Skyglow  
  Abstract An analytical framework to predict skyglow due to distant sources is presented, which can be applied to model sky brightness from the zenith toward the horizon along a vertical plane crossing the hemisphere in the azimuthal position of a light source. Although various powerful algorithms have been developed over the last few decades, the time needed for calculation grows exponentially with increasing size of the modelling domain. This is one of the key issues in skyglow computations, because the numerical accuracy improves only slowly as the modelling domain extends. We treat the problem theoretically, by introducing an analytical formula that is well-suited for light sources located at intermediate and long distances from an observation point and allows tremendous time savings in numerical analyses, while keeping the error at a low level. Field experiments carried out in Eastern Austria provided a unique opportunity to validate the model using real-sky luminance data. The fact that the theoretical model allows the prediction of sky luminance within an acceptable error tolerance is not only in line with the experimental data, but also provides new means of remote characterization of light emissions from artificial sources. The method is particularly attractive for rapid and simple retrieval of the amount of light escaping upwards from the dominant light sources surrounding the observation point. We expect that the method can advance the numerical modelling of skyglow substantially, because it allows real-time computations for very large territories.  
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  ISSN 0035-8711 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2258  
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Author Aubé, M.; Simoneau, A.; Wainscoat, R.; Nelson, L. url  doi
openurl 
  Title Modeling the effects of phosphor converted LED lighting to the night sky of the Haleakala Observatory, Hawaii Type Journal Article
  Year 2018 Publication Monthly Notices of the Royal Astronomical Society Abbreviated Journal  
  Volume (down) 478 Issue 2 Pages 1776-1783  
  Keywords Skyglow  
  Abstract The goal of this study is to evaluate the current level of light pollution in the night sky at the Haleakala Observatory on the island of Maui in Hawaii. This is accomplished with a numerical model that was tested in the first International Dark Sky Reserve located in Mont-Mégantic National Park in Canada. The model uses ground data on the artificial light sources present in the region of study, geographical data, and remotely sensed data for: 1) the nightly upward radiance; 2) the terrain elevation; and, 3) the ground spectral reflectance of the region. The results of the model give a measure of the current state of the sky spectral radiance at the Haleakala Observatory. Then, using the current state as a reference point, multiple light conversion plans are elaborated and evaluated using the model. We can thus estimate the expected impact of each conversion plan on the night sky radiance spectrum. A complete conversion to white (LEDs) with (CCT) of 4000K and 3000K are contrasted with a conversion using (PC) amber (LEDs). We include recommendations concerning the street lamps to be used in sensitive areas like the cities of Kahului and Kihei and suggest best lighting practices related to the color of lamps used at night.  
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  Series Volume Series Issue Edition  
  ISSN 0035-8711 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 1907  
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Author Kennard, D.C.; Chamberlin, V.D. url  openurl
  Title All-night Light for Layers Type Report
  Year 1931 Publication Abbreviated Journal  
  Volume (down) Bulletin 476 Issue Pages  
  Keywords Animals  
  Abstract  
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  Corporate Author Ohio Agricultural Experiment Station Thesis  
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  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2392  
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Author Bará, S. url  doi
openurl 
  Title Characterizing the zenithal night sky brightness in large territories: how many samples per square kilometre are needed? Type Journal Article
  Year 2017 Publication Monthly Notices of the Royal Astronomical Society Abbreviated Journal  
  Volume (down) 473 Issue 3 Pages 4164-4173  
  Keywords Instrumentation; atmospheric effects; light pollution; numerical methods; photometry  
  Abstract A recurring question arises when trying to characterize, by means of measurements or theoretical calculations, the zenithal night sky brightness throughout a large territory: how many samples per square kilometre are needed? The optimum sampling distance should allow reconstructing, with sufficient accuracy, the continuous zenithal brightness map across the whole region, whilst at the same time avoiding unnecessary and redundant oversampling. This paper attempts to provide some tentative answers to this issue, using two complementary tools: the luminance structure function and the Nyquist–Shannon spatial sampling theorem. The analysis of several regions of the world, based on the data from the New world atlas of artificial night sky brightness, suggests that, as a rule of thumb, about one measurement per square kilometre could be sufficient for determining the zenithal night sky brightness of artificial origin at any point in a region to within ±0.1 magV arcsec–2 (in the root-mean-square sense) of its true value in the Johnson–Cousins V band. The exact reconstruction of the zenithal night sky brightness maps from samples taken at the Nyquist rate seems to be considerably more demanding.  
  Address 1Departamento de Física Aplicada, Universidade de Santiago de Compostela, E-15782 Santiago de Compostela, Galicia, Spain; salva.bara(at)usc.es  
  Corporate Author Thesis  
  Publisher Oxford Academic Place of Publication Editor  
  Language English Summary Language English Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0035-8711 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 2164  
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Author Kocifaj, M.; Kómar, L. url  doi
openurl 
  Title A role of aerosol particles in forming urban skyglow and skyglow from distant cities Type Journal Article
  Year 2016 Publication Monthly Notices of the Royal Astronomical Society Abbreviated Journal MNRAS  
  Volume (down) 458 Issue 1 Pages 438-448  
  Keywords Skyglow; scattering; atmospheric effects; artificial light; numerical modeling; GIS-based modeling; light pollution  
  Abstract Aerosol particles may represent the largest uncertainty about skyglow change in many locations under clear sky conditions. This is because aerosols are ubiquitous in the atmosphere and influence the ground-reaching radiation in different ways depending on their concentrations, origins, shapes, sizes, and compositions. Large particles tend to scatter in Fraunhofer diffraction regime, while small particles can be treated in terms of Rayleigh formalism. However, the role of particle microphysics in forming the skyglow still remains poorly quantified. We have shown in this paper that the chemistry is somehow important for backscattering from large particles that otherwise work as efficient attenuators of light pollution if composed of absorbing materials. The contribution of large particles to the urban skyglow diminishes as they become more spherical in shape. The intensity of backscattering from non-absorbing particles is more-or-less linearly decreasing function of particle radius even if number size distribution is inversely proportional to the fourth power of particle radius. This is due to single particle backscattering that generally increases steeply as the particle radius approaches large values. Forward scattering depends on the particle shape but is independent of the material composition, thus allowing for a simplistic analytical model of skyglow from distant cities. The model we have developed is based on mean value theorem for integrals and incorporates the parametrizable Garstang's emission pattern, intensity decay along optical beam path, and near-forward scattering in an atmospheric environment. Such model can be used by modellers and experimentalists for rapid estimation of skyglow from distant light sources.  
  Address ICA, Slovak Academy of Sciences, Dúbravská Road 9, 845 03 Bratislava, Slovak Republic; kocifaj(at)savba.sk  
  Corporate Author Thesis  
  Publisher Oxford Journals Place of Publication Editor  
  Language English Summary Language English Original Title  
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  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 1361  
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