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Author Pun, C.S.J.; So, C.W. url  doi
openurl 
  Title Night-sky brightness monitoring in Hong Kong: a city-wide light pollution assessment Type Journal Article
  Year 2012 Publication Environmental Monitoring and Assessment Abbreviated Journal Environ Monit Assess  
  Volume (down) 184 Issue 4 Pages 2537-2557  
  Keywords *Cities; Environmental Monitoring/instrumentation/*methods; *Environmental Pollution; Hong Kong; Humans; *Light  
  Abstract Results of the first comprehensive light pollution survey in Hong Kong are presented. The night-sky brightness was measured and monitored around the city using a portable light-sensing device called the Sky Quality Meter over a 15-month period beginning in March 2008. A total of 1,957 data sets were taken at 199 distinct locations, including urban and rural sites covering all 18 Administrative Districts of Hong Kong. The survey shows that the environmental light pollution problem in Hong Kong is severe-the urban night skies (sky brightness at 15.0 mag arcsec(- 2)) are on average ~ 100 times brighter than at the darkest rural sites (20.1 mag arcsec(- 2)), indicating that the high lighting densities in the densely populated residential and commercial areas lead to light pollution. In the worst polluted urban location studied, the night-sky at 13.2 mag arcsec(- 2) can be over 500 times brighter than the darkest sites in Hong Kong. The observed night-sky brightness is found to be affected by human factors such as land utilization and population density of the observation sites, together with meteorological and/or environmental factors. Moreover, earlier night skies (at 9:30 p.m. local time) are generally brighter than later time (at 11:30 p.m.), which can be attributed to some public and commercial lightings being turned off later at night. On the other hand, no concrete relationship between the observed sky brightness and air pollutant concentrations could be established with the limited survey sampling. Results from this survey will serve as an important database for the public to assess whether new rules and regulations are necessary to control the use of outdoor lightings in Hong Kong.  
  Address Department of Physics, The University of Hong Kong, Pokfulam Road, Hong Kong, PR China. jcspun@hku.hk  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 0167-6369 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:21713499 Approved no  
  Call Number IDA @ john @ Serial 258  
Permanent link to this record
 

 
Author Levin, N.; Phinn, S. url  doi
openurl 
  Title Illuminating the capabilities of Landsat 8 for mapping night lights Type Journal Article
  Year 2016 Publication Remote Sensing of Environment Abbreviated Journal Remote Sensing of Environment  
  Volume (down) 182 Issue Pages 27-38  
  Keywords Remote Sensing; Instrumentation  
  Abstract Remote sensing of night-lights has been enhanced in recent years with the availability of the new VIIRS Day and Night band, the commercial EROS-B satellite and astronaut photographs from the International Space Station. However, dedicated space-borne multispectral sensors offering radiance calibrated night lights imagery are yet to be launched. Here we examined the capabilities of Landsat 8 to acquire night time light images of the Earth. Examining seven night-time Landsat 8 scenes, we found that brightly lit areas in both urban (Berlin, Las Vegas, Nagoya and Tel-Aviv) and gas flares (Basra, Kuwait) areas were detected in all eight bands of Landsat 8. The threshold for detection of lit areas was approximately 0.4 W/m2/μm/sr in bands 1–5 and 8 of Landsat 8. This threshold level was higher than Landsat dark noise levels, and slightly lower than post launch Landsat 8 OLI band dependent noise equivalent radiance difference levels. Drawing on this, we call on the USGS to plan an annual night-time acquisition of urban and gas flares areas globally, and to enable the performance of the future Landsat 10 to be established in a way that it will be sensitive enough to image the Earth at night, thus performing as Nightsat during the night.  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0034-4257 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number LoNNe @ kyba @ Serial 1452  
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Author Duriscoe, D.M. url  doi
openurl 
  Title Photometric indicators of visual night sky quality derived from all-sky brightness maps Type Journal Article
  Year 2016 Publication Journal of Quantitative Spectroscopy and Radiative Transfer Abbreviated Journal JQSRT  
  Volume (down) 181 Issue Pages 33-45  
  Keywords Skyglow; Instrumentation  
  Abstract Wide angle or fisheye cameras provide a high resolution record of artificial sky glow, which results from the scattering of escaped anthropogenic light by the atmosphere, over the sky vault in the moonless nocturnal environment. Analysis of this record yields important indicators of the extent and severity of light pollution. The following indicators were derived through numerical analysis of all-sky brightness maps: zenithal, average all-sky, median, brightest, and darkest sky brightness. In addition, horizontal and vertical illuminance, resulting from sky brightness were computed. A natural reference condition to which the anthropogenic component may be compared is proposed for each indicator, based upon an iterative analysis of a high resolution natural sky model. All-sky brightness data, calibrated in the V band by photometry of standard stars and converted to luminance, from 406 separate data sets were included in an exploratory analysis. Of these, six locations representing a wide range of severity of impact from artificial sky brightness were selected as examples and examined in detail. All-sky average brightness is the most unbiased indicator of impact to the environment, and is more sensitive and accurate in areas of slight to moderate light pollution impact than zenith brightness. Maximum vertical illuminance provides an excellent indicator of impacts to wilderness character, as does measures of the brightest portions of the sky. Zenith brightness, the workhorse of field campaigns, is compared to the other indicators and found to correlate well with horizontal illuminance, especially at relatively bright sites. The median sky brightness describes a brightness threshold for the upper half of the sky, of importance to telescopic optical astronomy. Numeric indicators, in concert with all-sky brightness maps, provide a complete assessment of visual sky quality at a site.  
  Address U.S. National Park Service, Natural Sounds and Night Skies Division, 351 Pacu Lane, Bishop, CA 93514, USA; dan_duriscoe(at)nps.gov  
  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 LoNNe @ kyba @ ; IDA @ john @ Serial 1376  
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Author Pravettoni, M.; Strepparava, D.; Cereghetti, N.; Klett, S.; Andretta, M.; Steiger, M. url  doi
openurl 
  Title Indoor calibration of Sky Quality Meters: linearity, spectral responsivity and uncertainty analysis Type Journal Article
  Year 2016 Publication Journal of Quantitative Spectroscopy and Radiative Transfer Abbreviated Journal Journal of Quantitative Spectroscopy and Radiative Transfer  
  Volume (down) 181 Issue in press Pages 74-86  
  Keywords Instrumentation  
  Abstract The indoor calibration of brightness sensors requires extremely low values of irradiance in the most accurate and reproducible way. In this work the testing equipment of an ISO 17025 accredited laboratory for electrical testing, qualification and type approval of solar photovoltaic modules was modified in order to test the linearity of the instruments from few mW/cm2 down to fractions of nW/cm2, corresponding to levels of simulated brightness from 6 to 19 mag/arcsec2. Sixteen Sky Quality Meter (SQM) produced by Unihedron, a Canadian manufacturer, were tested, also assessing the impact of the ageing of their protective glasses on the calibration coefficients and the drift of the instruments. The instruments are in operation on measurement points and observatories at different sites and altitudes in Southern Switzerland, within the framework of OASI, the Environmental Observatory of Southern Switzerland. The authors present the results of the calibration campaign: linearity; brightness calibration, with and without protective glasses; transmittance measurement of the glasses; and spectral responsivity of the devices. A detailed uncertainty analysis is also provided, according to the ISO 17025 standard.  
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  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 LoNNe @ kyba @ Serial 1399  
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Author Ma, S.; Yan, W.; Huang, Y.-X.; Ai, W.-H.; Zhao, X. url  doi
openurl 
  Title Vicarious calibration of S-NPP/VIIRS day-night band using deep convective clouds Type Journal Article
  Year 2015 Publication Remote Sensing of Environment Abbreviated Journal Remote Sensing of Environment  
  Volume (down) 158 Issue Pages 42-55  
  Keywords Instrumentation, Remote Sensing  
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  Series Volume Series Issue Edition  
  ISSN 0034-4257 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number LoNNe @ christopher.kyba @ Serial 1077  
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