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Author Kocifaj, M. url  doi
openurl 
  Title Light-pollution model for cloudy and cloudless night skies with ground-based light sources Type Journal Article
  Year 2007 Publication (up) Applied Optics Abbreviated Journal Appl. Opt.  
  Volume 46 Issue 15 Pages 3013  
  Keywords light pollution; modeling  
  Abstract The scalable theoretical model of light pollution for ground sources is presented. The model is successfully employed for simulation of angular behavior of the spectral and integral sky radiance and∕or luminance during nighttime. There is no restriction on the number of ground-based light sources or on the spatial distribution of these sources in the vicinity of the measuring point (i.e., both distances and azimuth angles of the light sources are configurable). The model is applicable for real finite-dimensional surface sources with defined spectral and angular radiating properties contrary to frequently used point-source approximations. The influence of the atmosphere on the transmitted radiation is formulated in terms of aerosol and molecular optical properties. Altitude and spectral reflectance of a cloud layer are the main factors introduced for simulation of cloudy and∕or overcast conditions. The derived equations are translated into numerically fast code, and it is possible to repeat the entire set of calculations in real time. The parametric character of the model enables its efficient usage by illuminating engineers and∕or astronomers in the study of various light-pollution situations. Some examples of numerical runs in the form of graphical results are presented.  
  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 0003-6935 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 277  
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Author Bará, S.; Nievas, M.; Sanchez de Miguel, A.; Zamorano, J. url  openurl
  Title Zernike analysis of all-sky night brightness maps Type Journal Article
  Year 2014 Publication (up) Applied Optics Abbreviated Journal Appl Opt  
  Volume 53 Issue 12 Pages 2677-2686  
  Keywords modeling; light at night; light pollution; all-sky; Zernike polynomials; image decomposition; sky brightness  
  Abstract All-sky night brightness maps (calibrated images of the night sky with hemispherical field-of-view (FOV) taken at standard photometric bands) provide useful data to assess the light pollution levels at any ground site. We show that these maps can be efficiently described and analyzed using Zernike circle polynomials. The relevant image information can be compressed into a low-dimensional coefficients vector, giving an analytical expression for the sky brightness and alleviating the effects of noise. Moreover, the Zernike expansions allow us to quantify in a straightforward way the average and zenithal sky brightness and its variation across the FOV, providing a convenient framework to study the time course of these magnitudes. We apply this framework to analyze the results of a one-year campaign of night sky brightness measurements made at the UCM observatory in Madrid.  
  Address Área de Óptica, Dept. de Física Aplicada, Fac. de Física, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Galicia, Spain  
  Corporate Author Thesis  
  Publisher Optical Society of America Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-6935 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:24787595 Approved no  
  Call Number IDA @ john @ Serial 318  
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Author Boscarino, B.T.; Rudstam, L.G.; Eillenberger, J.L.; O'Gorman, R. url  doi
openurl 
  Title Importance of light, temperature, zooplankton and fish in predicting the nighttime vertical distribution of Mysis diluviana Type Journal Article
  Year 2009 Publication (up) Aquat Biol Abbreviated Journal  
  Volume 5 Issue Pages 263-279  
  Keywords Animals; Mysis relicta; Modeling; Migration; Zooplankton; Vertical distribution; DVM  
  Abstract The opossum shrimp Mysis diluviana (formerly M. relicta) performs large amplitude diel vertical migrations in Lake Ontario and its nighttime distribution is influenced by temperature, light and the distribution of its predators and prey. At one location in southeastern Lake Ontario, we measured the vertical distribution of mysids, mysid predators (i.e. planktivorous fishes) and mysid prey (i.e. zooplankton), in addition to light and temperature, on 8 occasions from May to September, 2004 and 2005. We use these data to test 3 different predictive models of mysid habitat selection, based on: (1) laboratory-derived responses of mysids to different light and temperature gradients in the absence of predator or prey cues; (2) growth rate of mysids, as estimated with a mysid bioenergetics model, given known prey densities and temperatures at different depths in the water column; (3) ratio of growth rates (g) and mortality risk (μ) associated with the distribution of predatory fishes. The model based on light and temperature preferences was a better predictor of mysid vertical distribution than the models based on growth rate and g:μ on all 8 occasions. Although mysid temperature and light preferences probably evolved as mechanisms to reduce predation while increasing foraging intake, the response to temperature and light alone predicts mysid vertical distribution across seasons in Lake Ontario.  
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  Notes Approved no  
  Call Number LoNNe @ christopher.kyba @ Serial 402  
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Author Noll, S.; Kausch, W.; Barden, M.; Jones, A.M.; Szyszka, C.; Kimeswenger, S.; Vinther, J. url  doi
openurl 
  Title An atmospheric radiation model for Cerro Paranal: I. The optical spectral range* Type Journal Article
  Year 2012 Publication (up) Astronomy & Astrophysics Abbreviated Journal A&A  
  Volume 543 Issue Pages A92  
  Keywords atmospheric effects; site testing; radiative transfer; radiation mechanisms: general; scattering; techniques; spectroscopic; modeling; observatories; Cerro Paranal  
  Abstract Aims. The Earth’s atmosphere affects ground-based astronomical observations. Scattering, absorption, and radiation processes deteriorate the signal-to-noise ratio of the data received. For scheduling astronomical observations it is, therefore, important to accurately estimate the wavelength-dependent effect of the Earth’s atmosphere on the observed flux.

Methods. In order to increase the accuracy of the exposure time calculator of the European Southern Observatory’s (ESO) Very Large Telescope (VLT) at Cerro Paranal, an atmospheric model was developed as part of the Austrian ESO In-Kind contribution. It includes all relevant components, such as scattered moonlight, scattered starlight, zodiacal light, atmospheric thermal radiation and absorption, and non-thermal airglow emission. This paper focuses on atmospheric scattering processes that mostly affect the blue (<0.55&#8201;&#956;m) wavelength regime, and airglow emission lines and continuum that dominate the red (>0.55&#8201;&#956;m) wavelength regime. While the former is mainly investigated by means of radiative transfer models, the intensity and variability of the latter is studied with a sample of 1186 VLT FORS&#8201;1 spectra.

Results. For a set of parameters such as the object altitude angle, Moon-object angular distance, ecliptic latitude, bimonthly period, and solar radio flux, our model predicts atmospheric radiation and transmission at a requested resolution. A comparison of our model with the FORS&#8201;1 spectra and photometric data for the night-sky brightness from the literature, suggest a model accuracy of about 20%. This is a significant improvement with respect to existing predictive atmospheric models for astronomical exposure time calculators.
 
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0004-6361 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 274  
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Author Kocifaj, M. url  doi
openurl 
  Title Two-stream approximation for rapid modeling the light pollution levels in local atmosphere Type Journal Article
  Year 2012 Publication (up) Astrophysics and Space Science Abbreviated Journal Astrophys Space Sci  
  Volume 341 Issue 2 Pages 301-307  
  Keywords Light pollution; Atmospheric effects; Methods: numerical; Radiative transfer; Scattering; modeling; two-stream approximation  
  Abstract The two-stream concept is used for modeling the radiative transfer in Earth's atmosphere illuminated by ground-based light sources. The light pollution levels (illuminance and irradiance) are computed for various aerosol microphysical parameters, specifically the asymmetry parameter g A , single scattering albedo ω A , and optical thickness τ A . Two distinct size distributions of Junge's and gamma-type are employed. Rather then being a monotonic function of τ A , the diffuse illuminance/irradiance shows a local minimum at specific τ A, lim independent of size distribution taken into consideration. The existence of local minima has relation to the scattering and attenuation efficiencies both of which have opposite effects. The computational scheme introduced in this paper is advantageous especially if the entire set of calculations needs to be repeated with an aim to simulate diffuse light in various situations and when altering optical states of the atmospheric environment.  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0004-640X ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 273  
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Author Nievas Rosillo, M. pdf  url
openurl 
  Title Absolute photometry and Night Sky Brightness with all-sky cameras Type Report
  Year 2013 Publication (up) e-prints Complutense Abbreviated Journal e-prints Complutense  
  Volume Issue 24626 Pages  
  Keywords Instrumentation; skyglow; measurement; modeling  
  Abstract All-sky cameras have proven to be powerful tools to continuously monitoring the sky in a wide range of fields in both Astrophysics and Meteorology. In this work, we have developed a complete software pipeline to analyze the night CCD images obtained with one of such systems. This let us to study typical parameters used in Astrophysics to characterize the night sky quality, such as the Sky Brightness, the Cloud Coverage and the Atmospheric Extinction, how they evolve over the time and their variability. Using our software, we analyzed a large set of data from AstMon-OT all-sky camera at Teide Observatory. Results from this work have been applied in the support to the spanish CTA site proposal at Izaña, Tenerife and are being discussed within the CTA consortium. A comparison with data from other devices that have been used in site characterization such as the IAC80 telescope is also presented. This comparison is used to validate the results of the analysis of all-sky images. Finally, we test our software with AstMon-UCM and DSLR cameras. Some general recommendations for the use of DSLR cameras are provided.  
  Address Departamento de Astrofí­sica y Ciencias de la Atmosfera, Universidad Complutense de Madrid, Madrid, Spain  
  Corporate Author Thesis Master's thesis  
  Publisher Place of Publication Madrid Editor  
  Language English Summary Language English Original Title  
  Series Editor Series Title e-prints Complutense Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 1437  
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Author Troy, J.R.; Holmes, N.D.; Green, M.C. url  doi
openurl 
  Title Modeling artificial light viewed by fledgling seabirds Type Journal Article
  Year 2011 Publication (up) Ecosphere Abbreviated Journal Ecosphere  
  Volume 2 Issue 10 Pages art109  
  Keywords artificial light; fallout; Hydrobatidae; modeling; Newell's Shearwater; Procellariidae; Puffinus newelli; birds  
  Abstract Artificial light is increasing in coverage across the surface of our planet, impacting the behavioral ecology of many organisms. Attraction to sources of artificial light is a significant threat to certain fledgling shearwaters, petrels (Procellariidae), and storm-petrels (Hydrobatidae) on their first nocturnal flights to the sea. Disorientation by light can cause these birds to crash into vegetation or manmade structures, potentially resulting in death from physical injury, starvation, dehydration, predation by introduced predators, or collisions with vehicles. We developed a GIS-based method to model the intensity of artificial light that fledgling procellariids and hydrobatids could view en route to the ocean (to estimate the degree of threat that artificial light poses to these birds) and present two models for the island of Kauai as examples. These models are particularly relevant to the federally threatened Newell's Shearwater, or `A`o (Puffinus newelli), of which >30,000 fledglings have been collected in response to disorientation by lights on Kauai during the past 30 years. Our models suggest that there are few to no portions of Kauai from which young birds could fledge and not view light on their post-natal nocturnal flights, which is concerning given evidence of a Newell's Shearwater population decline. In future work using this technique, night light intensity layers could be altered to model the effects of modified coastal light conditions on known and potential procellariid and hydrobatid breeding locations. Furthermore, certain methods presented herein may be applicable to other seabirds and additional taxa in which attraction to anthropogenic light poses a serious threat, including migratory passerines and hatchling marine turtles. Components of this modeling approach could potentially be used to spatially estimate effects of other point-source threats to ecological systems, including sound and air pollution.  
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  Series Volume Series Issue Edition  
  ISSN 2150-8925 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 60  
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Author Troy, J.R.; Holmes, N.D.; Veech, J.A.; Green, M.C. url  doi
openurl 
  Title Using observed seabird fallout records to infer patterns of attraction to artificial light Type Journal Article
  Year 2013 Publication (up) Endangered Species Research Abbreviated Journal  
  Volume 22 Issue 3 Pages 225-234  
  Keywords Animals; Anthropogenic light; GIS-based modeling; Hawaii; Kauai; Light attraction; Procellariiformes; Newell’s shearwater; Seabird conservation  
  Abstract Attraction of fledgling shearwaters, petrels, and storm-petrels to artificial light has been documented for decades on islands around the world and is considered a significant threat to many species. Although large numbers of downed birds have been observed after being disoriented by light, several important elements of this ‘fallout’ phenomenon are unknown, including the locations along the path from nest to ocean at which attraction and/or disorientation occurs and whether fledglings can be attracted back to land after reaching the ocean in numbers large enough to contribute significantly to fallout. To investigate these questions, we compared observed Newell’s shearwater Puffinus newelli fallout records (from 1998 to 2009) on Kauai, USA, with expected numbers generated from several hypothetical models containing basic assumptions related to fledgling movement and attraction to light. Based on our results, the spatial pattern of observed fallout is consistent with the amount of light that fledglings may view along their first flights to and beyond the coastline. This suggests that even fledglings from dark regions of the island may not be safe because they may view light after reaching the ocean and still be susceptible to attraction. These findings support recent modeling efforts predicting that most birds fledging from Kauai are likely exposed to at least some anthropogenic light. As nocturnal use of light by humans is unlikely to be eliminated, research on the types of artificial light that are both useful to humans and safe for seabirds may be crucial for the conservation of these important marine animals.  
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  Notes Approved no  
  Call Number LoNNe @ christopher.kyba @ Serial 383  
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Author Zeng, C.; Zhou, Y.; Wang, S.; Yan, F.; Zhao, Q. url  doi
openurl 
  Title Population spatialization in China based on night-time imagery and land use data Type Journal Article
  Year 2011 Publication (up) International Journal of Remote Sensing Abbreviated Journal International Journal of Remote Sensing  
  Volume 32 Issue 24 Pages 9599-9620  
  Keywords DMSP-OLS; remote sensing; light at night; population; modeling  
  Abstract Population is a key indicator of socioeconomic development, urban planning and environmental protection, particularly for developing countries like China. But, census data for any given area are neither always available nor adequately reflect the internal differences of population. The authors tried to overcome this problem by spatializing the population across China through utilizing integer night-time imagery (Defense Meteorological Satellite Program/Operational Linescan System, DMSP/OLS) and land-use data. In creating the population linear regression model, night-time light intensity and lit areas, under different types of land use, were employed as predictor variables, and census data as dependent variables. To improve model performance, eight zones were created using night-time imagery clustering and shortest path algorithm. The population model is observed to have a coefficient of determination (R 2) ranging from 0.80 to 0.95 in the research area, which remained the same in different years. A comparison of the results of this study with those of other researchers shows that the spatialized population density map, prepared on the basis of night-time imagery, reflects the population distribution character more explicitly and in greater detail.  
  Address State Key Laboratory of Remote Sensing Science , Jointly Sponsored by the Institute of Remote Sensing Applications of the Chinese Academy of Sciences and Beijing Normal University , Beijing, 100101, PR China  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0143-1161 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 228  
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Author Kolláth, Z. url  doi
openurl 
  Title Measuring and modelling light pollution at the Zselic Starry Sky Park Type Journal Article
  Year 2010 Publication (up) Journal of Physics: Conference Series Abbreviated Journal J. Phys.: Conf. Ser.  
  Volume 218 Issue Pages 012001  
  Keywords Skyglow; modeling; measurement; SQM; sky brightness; Zselic; International Dark Sky Park; Hungry; measurements; modeling; light pollution; skyglow; radiative transfer  
  Abstract One of the first 'International Dark-sky Parks' in Europe was established at the Zselic Landscape Protection Area in Hungary. A special monitoring program has been carrying on to survey the quality of the night sky using 'Sky Quality Meters' and DSLR cameras. The main conclusion of our measurements is that the local villages have only a minimal effect on the quality of the sky. There are light-domes due to the neighbouring cities only close to the horizon, the main source of obtrusive light is the city of Kaposvár. The anthropogenic component of zenith luminance of the night sky is obtained as the function of the distance from the city centre of Kaposvár. Our data were modelled by radiation transfer calculations. These results can help to draw attention to the energy emitted useless to the space and to protect our nocturnal landscape of nature parks for the next generations.  
  Address Konkoly Observatory, Konkoly Thege u. 15-17, H-1121 Budapest, Hungary; kollath(at)konkoly.hu  
  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 1742-6596 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number IDA @ john @ Serial 1436  
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