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Author ![]() |
Aubé, M. | ||||
Title | Physical behaviour of anthropogenic light propagation into the nocturnal environment | Type | Journal Article | ||
Year | 2015 | Publication | Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences | Abbreviated Journal | Philos Trans R Soc Lond B Biol Sci |
Volume | 370 | Issue | Pages | 20140117 | |
Keywords | Skyglow; artificial light at night; light pollution; radiative transfer; atmospheric effects; scattering; methods; numerical; sensitivity analysis | ||||
Abstract | Propagation of artificial light at night (ALAN) in the environment is now known to have non negligible consequences on fauna, flora and human health. These consequences depend on light levels and their spectral power distributions, which in turn rely on the efficiency of various physical processes involved in the radiative transfer of this light into the atmosphere and its interactions with the built and natural environment. ALAN can affect the living organisms by direct lighting and indirect lighting (scattered by the sky and clouds and/or reflected by local surfaces). This paper mainly focuses on the behaviour of the indirect light scattered under clear sky conditions. Various interaction processes between anthropogenic light sources and the natural environment are discussed. This work mostly relies on a sensitivity analysis conducted with the light pollution radiative transfer model, Illumina (Aubé et al. 2005: Light pollution modelling and detection in a heterogeneous environment: toward a night-time aerosol optical depth retrieval method. In Proc. SPIE 2005, vol. 5890, San Diego, California, USA). More specifically, the impact of (i) the molecular and aerosol scattering and absorption, (ii) the second order of scattering, (iii) the topography and obstacle blocking, (iv) the ground reflectance and (v) the spectrum of light devices and their angular emission functions are examined. This analysis considers different behaviour as a function of the distance from the city centre, along with different zenith viewing angles in the principal plane. | ||||
Address | Département de physique, Cégep de Sherbrooke, Sherbrooke, Quebec, Canada | ||||
Corporate Author | Thesis | ||||
Publisher | Royal Society | Place of Publication | Editor | ||
Language | English | Summary Language | English | Original Title | |
Series Editor | Series Title | The biological impacts of artificial light at night: from molecules to communities | Abbreviated Series Title | ||
Series Volume | Series Issue | Edition | |||
ISSN | ISBN | Medium | |||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | IDA @ john @ | Serial | 1115 | ||
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Author ![]() |
Biggs, J.D.; Fouché, T.; Bilki, F.; Zadnik, M.G. | ||||
Title | Measuring and mapping the night sky brightness of Perth, Western Australia: Night sky brightness of Perth | Type | Journal Article | ||
Year | 2012 | Publication | Monthly Notices of the Royal Astronomical Society | Abbreviated Journal | |
Volume | 421 | Issue | 2 | Pages | 1450-1464 |
Keywords | scattering; atmospheric effects; light pollution; techniques: photometric | ||||
Abstract | In order to study the light pollution produced in the city of Perth, Western Australia, we have used a hand-held sky brightness meter to measure the night sky brightness across the city. The data acquired facilitated the creation of a contour map of night sky brightness across the 2400 km2 area of the city – the first such map to be produced for a city. Importantly, this map was created using a methodology borrowed from the field of geophysics – the well proven and rigorous techniques of geostatistical analysis and modelling. A major finding of this study is the effect of land use on night sky brightness. By overlaying the night sky brightness map on to a suitably processed Landsat satellite image of Perth we found that locations near commercial and/or light industrial areas have a brighter night sky, whereas locations used for agriculture or having high vegetation coverage have a fainter night sky than surrounding areas. Urban areas have intermediate amounts of vegetation and are intermediate in brightness compared with the above-mentioned land uses. Regions with a higher density of major highways also appear to contribute to increased night sky brightness. When corrected for the effects of direct illumination from high buildings, we found that the night sky brightness in the central business district (CBD) is very close to that expected for a city of Perth’s population from modelling work and observations obtained in earlier studies. Given that our night sky brightness measurements in Perth over 2009 and 2010 are commensurate with that measured in Canadian cities over 30 years earlier implies that the various lighting systems employed in Perth (and probably most other cities) have not been optimised to minimize light pollution over that time. We also found that night sky brightness diminished with distance with an exponent of approximately −0.25 ± 0.02 from 3.5 to 10 km from the Perth CBD, a region characterized by urban and commercial land use. For distances from 10 out to about 40 km from the CBD the radial variation of night sky brightness steepens to have an exponent value of approximately −1.8 ± 0.2. This steepening is associated with land use because vegetation cover increases with further distance from the CBD. |
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Address | Curtin Institute of Radio Astronomy, Department of Imaging and Applied Physics, Curtin University, Bentley 6102, WA, Australia | ||||
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 | Approved | no | |||
Call Number | IDA @ john @ | Serial | 257 | ||
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Author ![]() |
Cinzano, P.; Elvidge, C.D. | ||||
Title | Night sky brightness at sites from DMSP-OLS satellite measurements | Type | Journal Article | ||
Year | 2004 | Publication | Monthly Notices of the Royal Astronomical Society | Abbreviated Journal | MNRAS |
Volume | 353 | Issue | 4 | Pages | 1107-1116 |
Keywords | scattering; atmospheric effects; light pollution; site testing; GTOPO30; DMSP | ||||
Abstract | We apply the sky brightness modelling technique introduced and developed by Roy Garstang to high-resolution satellite measurements of upward artificial light flux carried out with the US Air Force Defense Meteorological Satellite Program Operational Linescan System and to GTOPO30 (a global digital elevation model by the US Geological Survey's EROS Data Centre) digital elevation data in order to predict the brightness distribution of the night sky at a given site in the primary astronomical photometric bands for a range of atmospheric aerosol contents. This method, based on global data and accounting for elevation, Earth curvature and mountain screening, allows the evaluation of sky glow conditions over the entire sky for any site in the world, to evaluate its evolution, to disentangle the contribution of individual sources in the surrounding territory and to identify the main contributing sources. Sky brightness, naked eye stellar visibility and telescope limiting magnitude are produced as three-dimensional arrays, the axes of which are the position on the sky and the atmospheric clarity. We compare our results with available measurements. | ||||
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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 | Approved | no | |||
Call Number | IDA @ john @ | Serial | 172 | ||
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Author ![]() |
Cinzano, P.; Falchi, F. | ||||
Title | Quantifying light pollution | Type | Journal Article | ||
Year | 2014 | Publication | Journal of Quantitative Spectroscopy and Radiative Transfer | Abbreviated Journal | Journal of Quantitative Spectroscopy and Radiative Transfer |
Volume | 139 | Issue | Pages | 13-20 | |
Keywords | Atmospheric effects; Astronomical site testing; Scattering; Light pollution; Radiative transfer; Night sky brightness; Environmental pollution; Atmospheric pollution Corresponding author contact information | ||||
Abstract | In this paper we review new available indicators useful to quantify and monitor light pollution, defined as the alteration of the natural quantity of light in the night environment due to introduction of manmade light. With the introduction of recent radiative transfer methods for the computation of light pollution propagation, several new indicators become available. These indicators represent a primary step in light pollution quantification, beyond the bare evaluation of the night sky brightness, which is an observational effect integrated along the line of sight and thus lacking the three-dimensional information. | ||||
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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 | 0022-4073 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | IDA @ john @ | Serial | 177 | ||
Permanent link to this record | |||||
Author ![]() |
Cinzano, P.; Falchi, F. | ||||
Title | The propagation of light pollution in the atmosphere | Type | Journal Article | ||
Year | 2012 | Publication | Monthly Notices of the Royal Astronomical Society | Abbreviated Journal | Monthly Notices of the Royal Astronomical Society |
Volume | 427 | Issue | 4 | Pages | 3337-3357 |
Keywords | radiative transfer; scattering; atmospheric effects; light pollution; site testing; light at night; Garstang model; LPTRAN; DMSP-OLS; GTOPO30; modeling; propagation | ||||
Abstract | Recent methods to map artificial night-sky brightness and stellar visibility across large territories or their distribution over the entire sky at any site are based on computation of the propagation of light pollution with Garstang models, a simplified solution of the radiative transfer problem in the atmosphere that allows fast computation by reducing it to a ray-tracing approach. They are accurate for a clear atmosphere, when a two-scattering approximation is acceptable, which is the most common situation. We present here up-to-date extended Garstang models (EGM), which provide a more general numerical solution for the radiative transfer problem applied to the propagation of light pollution in the atmosphere. We also present the LPTRAN software package, an application of EGM to high-resolution Defense Meteorological Satellite Program (DMSP) Operational Linescan System (OLS) satellite measurements of artificial light emission and to GTOPO30 (Global 30 Arcsecond) digital elevation data, which provides an up-to-date method to predict the artificial brightness distribution of the night sky at any site in the world at any visible wavelength for a broad range of atmospheric situations and the artificial radiation density in the atmosphere across the territory. EGM account for (i) multiple scattering, (ii) wavelengths from 250 nm to infrared, (iii) the Earth's curvature and its screening effects, (iv) site and source elevation, (v) many kinds of atmosphere with the possibility of custom set-up (e.g. including thermal inversion layers), (vi) a mix of different boundary-layer aerosols and tropospheric aerosols, with the possibility of custom set-up, (vii) up to five aerosol layers in the upper atmosphere, including fresh and aged volcanic dust and meteoric dust, (viii) variations of the scattering phase function with elevation, (ix) continuum and line gas absorption from many species, ozone included, (x) up to five cloud layers, (xi) wavelength-dependent bidirectional reflectance of the ground surface from National Aeronautics and Space Administration (NASA) Moderate-Resolution Imaging Spectroradiometer (MODIS) satellite data, main models or custom data (snow included) and (xii) geographically variable upward light-emission function given as a three-parameter function or a Legendre polynomial series. Atmospheric scattering properties or light-pollution propagation functions from other sources can also be applied. A more general solution allows us to account also for (xiii) mountain screening, (xiv) geographical gradients of atmospheric conditions, including localized clouds and (xv) geographic distribution of ground surfaces, but suffers from too heavy computational requirements. Comparisons between predictions of classic Garstang models and EGM show close agreement for a US62 standard clear atmosphere and typical upward emission function. | ||||
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 | Approved | no | |||
Call Number | IDA @ john @ | Serial | 271 | ||
Permanent link to this record |