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Author Kocifaj, M. url  doi
openurl 
  Title Ground albedo impacts on higher-order scattering spectral radiances of night sky 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) 106670  
  Keywords skyglow  
  Abstract The contribution from ground reflected light to the night sky radiance is of increased interest because of constant modernization of street lighting systems that now efficiently eliminate light emissions above the horizontal plane, so the appreciable fraction of artificial light directed upwards is from ground reflection. Diffuse light of a night sky shows a positive correlation with ground albedo (α), but it seems there is no linear trend between α and the night sky brightness (NSB), at least not for all sky elements, and, the mechanism of this relationship becomes even more complicated due to multiple scattering effects. The extent to which the ground reflectance influences the higher-order scattering radiance of night sky, and, the factors that initiate the crossover from single- to multiple-scattering dominance of the sky glow has been virtually unexplored until now.

We demonstrate here that albedo-induced effects in NSB exhibit an angular dependence, with amplitudes enhanced towards shorter wavelengths. For low values of ground reflectance and at short distances from a light source, the second-scattering radiance is found to be only a few percent of the first-order scattering radiance. However, the ratio of a higher- to the first-order scattering radiance gradually increases near horizon, specifically at the side opposite to the azimuthal position of the light source. Also the NSB in blue band has decreasing gradation tendency when increasing the altitude above sea level. The findings in this paper are significant in a proper incorporation of higher-order scattering in modeling the NSB under elevated reflectance conditions, and may be critical for saving computational time.
 
  Address  
  Corporate Author Thesis  
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  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 2679  
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 Xu, P.; Wang, Q.; Jin, J.; Jin, P. url  doi
openurl 
  Title An increase in nighttime light detected for protected areas in mainland China based on VIIRS DNB data Type Journal Article
  Year 2019 Publication Ecological Indicators Abbreviated Journal Ecological Indicators  
  Volume 107 Issue Pages (down) 105615  
  Keywords Remote Sensing  
  Abstract Protected areas, a globally accepted conservation strategy, play a fundamental role in biodiversity and species conservation. There are increasing concerns about the ecological influence of nighttime light within protected areas due to the emergence of more light-related ecological issues. Previous approaches for detecting nighttime light mainly used the traditional data source released by the Defense Meteorological Satellite Program Operational Linescan System (DMSP/OLS), but its coarse spatial resolution and limited radiometric resolution dramatically hamper prompt detection. In this study, we used data from a new source, the Visible Infrared Imaging Radiometer Suite Day-Night Band (VIIRS DNB) to detect nighttime light disturbance within protected areas of mainland China. Protected areas extracted from Landsat 8 Operational Land Imager and the Thermal Infrared Sensor (OLI-TIRS) images served as ground truths to assess detection accuracy. We found that the VIIRS DNB data provided more and better details compared with the traditional DMSP/OLS data. Pixel-based trend analysis clearly indicated that within the protected areas lighted pixels existed extensively and increased significantly from 2012 to 2017. This study provides a new solution to better understand human activities within protected areas.  
  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 2612  
Permanent link to this record
 

 
Author Bará, S.; Ribas, S.; Kocifaj, M. url  doi
openurl 
  Title Modal evaluation of the anthropogenic night sky brightness at arbitrary distances from a light source Type Journal Article
  Year 2015 Publication Journal of Optics Abbreviated Journal J. of Optics  
  Volume 17 Issue Pages (down) 105607  
  Keywords Skyglow; light propagation, atmospheric optics, light pollution  
  Abstract The artificial emissions of light contribute to a high extent to the observed brightness of the night sky in many places of the world. Determining the all-sky radiance of anthropogenic origin requires solving the radiative transfer equation for ground-level light sources, generally resorting to a double-scattering approximation in order to account for the observed radiance patterns with a reasonable degree of accuracy. Since the all-sky radiance distribution produced by an elementary light source depends on the distance to the observer in a way that is not immediately obvious, the contributions of sources located at different distances have to be computed on an individual basis, solving for each one the corresponding scattering integrals. In this paper we show that these calculations may be significantly alleviated by using a modal approach, whereby the hemispheric night-sky radiance is expanded in terms of a convenient basis of two-dimensional (2D) orthogonal functions. Since the modal coefficients of this expansion do vary smoothly with the distance to the observer, the all-sky brightness distributions produced by light sources located at arbitrary intermediate distances can be efficiently estimated by interpolation, provided that the coefficients at a discrete set of distances are accurately determined beforehand.  
  Address Area de Optica, Universidade de Santiago de Compostela Campus Sur, E-15782, Santiago de Compostela, Spain; salva.bara(at)usc.es  
  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 2040-8986 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 1235  
Permanent link to this record
 

 
Author Obayashi, K.; Yamagami, Y.; Tatsumi, S.; Kurumatani, N.; Saeki, K. url  doi
openurl 
  Title Indoor light pollution and progression of carotid atherosclerosis: A longitudinal study of the HEIJO-KYO cohort Type Journal Article
  Year 2019 Publication Environment International Abbreviated Journal Environment International  
  Volume 133 Issue Pages (down) 105184  
  Keywords Human Health  
  Abstract Exposure to light at inappropriate times in relation to the solar cycle can disturb circadian endocrine and metabolic rhythms. Previous studies have suggested an association between light exposure at night (LAN) and obesity, an important risk factor of atherosclerosis, although it remains unclear whether LAN associates with progression of atherosclerosis. To evaluate the longitudinal association between bedroom LAN intensity and progression of carotid atherosclerosis, light intensity in the bedroom at baseline and carotid artery intima-media thickness (IMT) at baseline and follow-up were measured in 989 elderly participants (945 at baseline and 780 at a median follow-up time of 34 months). The mean age of the participants was 71.4 ± 6.9 years. The average mean and maximal carotid IMT at baseline were 0.88 ± 0.15 and 1.10 ± 0.32 mm, respectively. The median intensity of bedroom LAN was 0.68 lx (IQR, 0.07–3.29). In multivariable analysis adjusted for potential confounders, the highest LAN group exhibited a significant increase in mean carotid IMT (adjusted β, 0.028; 95% CI, 0.005–0.052; P = 0.019) compared with the lowest LAN quartile group. A similar relationship was found between LAN and maximal carotid IMT (adjusted β, 0.083; 95% CI, 0.037–0.129; P < 0.001).

In conclusion, we found a clear and significant association between bedroom LAN intensity and progression of subclinical carotid atherosclerosis, which was independent of known risk factors for atherosclerosis, including age, obesity, smoking, economic status, hypertension, and diabetes. Indoor light pollution may be a potential risk factor for atherosclerosis in the general population.
 
  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 0160-4120 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2706  
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