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Author Aubé, M.; Kocifaj, M.; Zamorano, J.; Solano Lamphar, H.A.; Sanchez de Miguel, A.
Title The spectral amplification effect of clouds to the night sky radiance in Madrid Type Journal Article
Year 2016 Publication Journal of Quantitative Spectroscopy and Radiative Transfer Abbreviated Journal Journal of Quantitative Spectroscopy and Radiative Transfer
Volume 181 Issue Pages 11-23
Keywords Skyglow; Madrid; Spain; Europe; artificial light at night; light pollution; clouds; amplification
Abstract Artificial Light at Night (ALAN) may have various environmental impacts ranging from compromising the visibility of astronomical objects to the perturbation of circadian cycles in animals and humans. In the past much research has been carried out to study the impact of ALAN on the radiance of the night sky during clear sky conditions. This was mainly justified by the need for a better understanding of the behavior of ALAN propagation into the environment in order to protect world-class astronomical facilities. More recently, alongside to the threat to the natural starry sky, many issues have emerged from the biological science community. It has been shown that, nearby or inside cities, the presence of cloud cover generally acts as an amplifier for artificial sky radiance while clouds behave as attenuators for remote observers. In this paper we show the spectral behavior of the zenith sky radiance amplification factor exerted by clouds inside a city. We compare in-situ measurements made with the spectrometer SAND-4 with a numerical model applied to the specific geographical context of the Universidad Complutense de Madrid in Spain.
Address Cégep de Sherbrooke, 475 rue du Cégep, Sherbrooke, Canada J1E 4K1; aubema(at)gmail.com
Corporate Author Thesis (down)
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 1351
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Author Jechow, A.; Hölker, F.; Kolláth, Z.; Gessner, M.O.; Kyba, C.C.M.
Title Evaluating the summer night sky brightness at a research field site on Lake Stechlin in northeastern Germany Type Journal Article
Year 2016 Publication Journal of Quantitative Spectroscopy and Radiative Transfer Abbreviated Journal Journal of Quantitative Spectroscopy and Radiative Transfer
Volume 181 Issue Pages 24-32
Keywords Skyglow
Abstract We report on luminance measurements of the summer night sky at a field site on a freshwater lake in northeastern Germany (Lake Stechlin) to evaluate the amount of artificial skyglow from nearby and distant towns in the context of a planned study on light pollution. The site is located about 70 km north of Berlin in a rural area possibly belonging to one of the darkest regions in Germany. Continuous monitoring of the zenith sky luminance between June and September 2015 was conducted utilizing a Sky Quality Meter. With this device, typical values for clear nights in the range of 21.5–21.7 magSQM/arcsec2 were measured, which is on the order of the natural sky brightness during starry nights. On overcast nights, values down to 22.84 magSQM/arcsec2 were obtained, which is about one third as bright as on clear nights. The luminance measured on clear nights as well as the darkening with the presence of clouds indicate that there is very little influence of artificial skyglow on the zenith sky brightness at this location. Furthermore, fish-eye lens sky imaging luminance photometry was performed with a digital single-lens reflex camera on a clear night in the absence of moonlight. The photographs unravel several distant towns as possible sources of light pollution on the horizon. However, the low level of artificial skyglow makes the field site at Lake Stechlin an excellent location to study the effects of skyglow on a lake ecosystem in a controlled fashion.
Address
Corporate Author Thesis (down)
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 LoNNe @ kyba @; GFZ @ kyba @ Serial 1354
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Author Kocifaj, M.; Kómar, L.
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 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 (down)
Publisher Oxford Journals Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 1361
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Author Hüppop, O.; Hüppop, K.; Dierschke, J.; Hill, R.
Title Bird collisions at an offshore platform in the North Sea Type Journal Article
Year 2016 Publication Bird Study Abbreviated Journal Bird Study
Volume 63 Issue 1 Pages 73-82
Keywords Animals; Ecology
Abstract Capsule Collisions with offshore structures in the North Sea could account for the mortality of hundreds of thousands of nocturnally migrating birds.

Aims To assess, for the first time, the circumstances of mass fatalities at an offshore structure, including the species involved, their numbers, ages, body conditions and injuries.

Methods At an unmanned tall offshore research platform in the southeastern North Sea, bird corpses were collected on 160 visiting days from October 2003 to December 2007. Corpses were identified to species and kinds of injury, ages, and fat and muscle scores were determined. Nocturnal bird calls were recorded, identified to species and quantified. Local and large-scale weather parameters were also considered.

Results A total of 767 birds of 34 species, mainly thrushes, European Starlings and other passerines, were found at 45 visits. Most carcasses were in good body condition and young birds were not more affected than adults. Three quarters of 563 examined individuals had collision induced injuries. Birds in poor body condition were less likely to be collision victims than those in good condition. Mass collision events at the illuminated offshore structure coincided with increasingly adverse weather conditions and an increasing call intensity of nocturnal birds.

Conclusions Assuming an average of 150 dead birds per year at this single offshore structure and additionally assuming that a considerable proportion of the corpses were not found, we estimate that mortality at the 1000 + human structures in the North Sea could reach hundreds of thousands of birds. Since offshore industrialization will progress and collision numbers at offshore turbines will consequently increase considerably, we recommend reinforced measures to reduce bird strikes at offshore structures, especially in the light of substantial declines in some migrant species.
Address
Corporate Author Thesis (down)
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0006-3657 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number LoNNe @ kyba @ Serial 1377
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Author Gibbons, R.; Terry, T.; Bhagavathula, R.; Meyer, J.; Lewis, A.
Title Applicability of mesopic factors to the driving task Type Journal Article
Year 2015 Publication Lighting Research and Technology Abbreviated Journal Lighting Research and Technology
Volume 48 Issue 1 Pages 70-82
Keywords Lighting; Public Safety; Planning
Abstract With the advent of light-emitting diode technology being applied to roadway lighting, the spectral power distribution of the light source is becoming much more important. In this experiment, the detection of pedestrians at five adaptation levels under three light sources, high pressure sodium and light emitting diodes of two colour temperatures was measured in realistic roadway scenarios. The results show that while the light source type was not significant, an increase in adaptation luminance increased the detection distance. As the offset of the object to the roadway increased, some spectral effects became more significant; however, this effect was not consistent across all angles of eccentricity. The conclusions from this work indicate that mesopic factors may not be applicable on high-speed roads.
Address
Corporate Author Thesis (down)
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1477-1535 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number LoNNe @ kyba @ Serial 1382
Permanent link to this record