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Author Bará, S.; Falchi, F.; Furgoni, R.; Lima, R.C. url  doi
openurl 
  Title Fast Fourier-transform calculation of artificial night sky brightness maps Type Journal Article
  Year 2020 Publication Journal of Quantitative Spectroscopy and Radiative Transfer Abbreviated Journal Journal of Quantitative Spectroscopy and Radiative Transfer  
  Volume 240 Issue Pages (down) 106658  
  Keywords Skyglow; Light pollution; Atmospheric optics; Photometry; Radiometry; Fourier transforms  
  Abstract Light pollution poses a growing threat to optical astronomy, in addition to its detrimental impacts on the natural environment, the intangible heritage of humankind related to the contemplation of the starry sky and, potentially, on human health. The computation of maps showing the spatial distribution of several light pollution related functions (e.g. the anthropogenic zenithal night sky brightness, or the average brightness of the celestial hemisphere) is a key tool for light pollution monitoring and control, providing the scientific rationale for the adoption of informed decisions on public lighting and astronomical site preservation. The calculation of such maps from satellite radiance data for wide regions of the planet with sub-kilometric spatial resolution often implies a huge amount of basic pixel operations, requiring in many cases extremely large computation times. In this paper we show that, using adequate geographical projections, a wide set of light pollution map calculations can be reframed in terms of two-dimensional convolutions that can be easily evaluated using conventional fast Fourier-transform (FFT) algorithms, with typical computation times smaller than 10^-6 s per output pixel.  
  Address Departamento de Física Aplicada, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Galicia, Spain; salva.bara(at)usc.es  
  Corporate Author Thesis  
  Publisher Elsevier Place of Publication Editor  
  Language English Summary Language English 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 2782  
Permanent link to this record
 

 
Author Wallner, S.; Kocifaj, M. url  doi
openurl 
  Title Impacts of surface albedo variations on the night sky brightness – A numerical and experimental analysis Type Journal Article
  Year 2019 Publication Journal of Quantitative Spectroscopy and Radiative Transfer Abbreviated Journal Journal of Quantitative Spectroscopy and Radiative Transfer  
  Volume 239 Issue Pages (down) 106648  
  Keywords Skyglow; albedo; surface albedo; Sky Quality Meter; Austria; Europe  
  Abstract The aim of this paper is to analyze surface albedo impacts on artificial night sky brightness at zenith. The way in which these parameters correlate with each other is analyzed numerically and then experimentally by Sky Quality Meters (SQMs) in the city of Linz, Austria between 2016 and 2018. Three SQMs are located in city areas that differ in ground type, while other two are installed outside but near the city. To eliminate systematic errors of different SQMs or a missing inter-calibration of all devices, we examine relative change in zenithal brightness instead of its absolute values. However, the ground albedo not only depends on the ground type, but also shows seasonal variation most often driven by vegetation and environmental change. To understand these changes, we use SkyGlow simulator to perform numerical experiments on four different albedo models. The results have proven that seasonal variations are clearly visible as green city parts become darker around autumn and ratios to urban located SQMs increase. We show that there is a major difference in simulation results if either conducting city parts with various surface albedos or using only one averaged value over the whole city. The latter produces worse fit to the observed SQM data, implying that a use of various surface albedos is a need when modelling zenithal brightness in artificially lit areas of a city or town. Also, the seasonal changes of surface albedo cannot be neglected and the parameter itself must be included in the modelling tools.  
  Address Department of Astrophysics, University of Vienna, Türkenschanzstrasse 17, 1180 Vienna, Austria; stefan.wallner(at)univie.ac.at  
  Corporate Author Thesis  
  Publisher Elsevier Place of Publication Editor  
  Language English Summary Language English 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 GFZ @ kyba @ Serial 2675  
Permanent link to this record
 

 
Author Bará, S.; Rigueiro, I.; Lima, R.C. url  doi
openurl 
  Title Monitoring transition: Expected night sky brightness trends in different photometric bands Type Journal Article
  Year 2019 Publication Journal of Quantitative Spectroscopy and Radiative Transfer Abbreviated Journal Journal of Quantitative Spectroscopy and Radiative Transfer  
  Volume 239 Issue Pages (down) 106644  
  Keywords Skyglow; Remote Sensing; Instrumentation  
  Abstract Several light pollution indicators are commonly used to monitor the effects of the transition from outdoor lighting systems based on traditional gas-discharge lamps to solid-state light sources. In this work we analyze a subset of these indicators, including the artificial zenithal night sky brightness in the visual photopic and scotopic bands, the brightness in the specific photometric band of the widely used Sky Quality Meter (SQM), and the top-of-atmosphere radiance detected by the VIIRS-DNB radiometer onboard the satellite Suomi-NPP. Using a single-scattering approximation in a layered atmosphere we quantitatively show that, depending on the transition scenarios, these indicators may show different, even opposite behaviors. This is mainly due to the combined effects of the changes in the sources' spectra and angular radiation patterns, the wavelength-dependent atmospheric propagation processes and the differences in the detector spectral sensitivity bands. It is suggested that the possible presence of this differential behavior should be taken into account when evaluating light pollution indicator datasets for assessing the outcomes of public policy decisions regarding the upgrading of outdoor lighting systems.  
  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 0022-4073 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2810  
Permanent link to this record
 

 
Author Beresford, A.E.; Donald, P.F.; Buchanan, G.M. url  doi
openurl 
  Title Repeatable and standardised monitoring of threats to Key Biodiversity Areas in Africa using Google Earth Engine Type Journal Article
  Year 2020 Publication Ecological Indicators Abbreviated Journal Ecological Indicators  
  Volume 109 Issue Pages (down) 105763  
  Keywords Remote Sensing  
  Abstract Key Biodiversity Areas (KBAs) are sites that make significant contributions to the global persistence of biodiversity, but identification of sites alone is not sufficient to ensure their conservation. Monitoring is essential if pressures on these sites are to be identified, priorities set and appropriate responses developed. Here, we describe how analysis of freely available data on a cloud-processing platform (Google Earth Engine) can be used to assess changes in three example remotely sensed threat indicators (fire frequency, tree loss and night-time lights) over time on KBAs in Africa. We develop easily repeatable methods with shared code that could be applied across any geographic area and could be adapted and applied to other datasets as they become available. Fire frequency was found to have increased significantly on 12.4% of KBAs and 15.9% of ecoregions, whilst rates of forest loss increased significantly on 24.3% of KBAs and 22.6% of ecoregions. There was also evidence of significant increases in night-time lights on over half (53.3%) of KBAs and 39.6% of ecoregions between 1992 and 2013, and on 11.6% of KBAs and 53.0% of ecoregions between 2014 and 2018.  
  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 1470160X ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2707  
Permanent link to this record
 

 
Author Jiang, J.; He, Y.; Kou, H.; Ju, Z.; Gao, X.; Zhao, H. url  doi
openurl 
  Title The effects of artificial light at night on Eurasian tree sparrow (Passer montanus): Behavioral rhythm disruption, melatonin suppression and intestinal microbiota alterations Type Journal Article
  Year 2020 Publication Ecological Indicators Abbreviated Journal Ecological Indicators  
  Volume 108 Issue Pages (down) 105702  
  Keywords Animals; Artificial light at night; Eurasian tree sparrow; Melatonin; Intestinal microbiota  
  Abstract Artificial light at night (ALAN) or light pollution is rapidly widespread with fast urbanization and becomes an obvious environmental disturbance. Recent studies showed ALAN has multiple negative impacts on a wide range of species including bird biological rhythm disruption, behavioral and physiological disturbance and hormone secretion disorder. However, its effects on bird gut microbiota are scarcely studied. In this study, we used Eurasian tree sparrow (Passer montanus), a widely distributed and locally abundant bird species in both urban and rural areas of China to examine the effects of ALAN on locomotor activity rhythm and melatonin secretion, and species diversity and community structure of intestinal microbiota by simulating urban and rural night light environment. Our results showed ALAN strongly affected circadian rhythm of locomotor activity with earlier start of activity before light-on and later rest after light-off. Moreover, ALAN significantly suppressed melatonin release. Last but not least, ALAN profoundly affected taxonomic compositions, species diversity and community structure of intestinal microbiota of birds. We concluded that ALAN may cause bird health damage by disrupting circadian rhythm, inhibiting melatonin release and altering intestinal microbiota. Melatonin hormone level and intestinal microbiota diversity may be important bioindicators for light pollution.  
  Address College of Life Sciences, Shaanxi Normal University, Xi’an 710119, China  
  Corporate Author Thesis  
  Publisher Elsevier Place of Publication Editor  
  Language English Summary Language English Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1470160X ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 2781  
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