Scientific Reports Sci Rep 2045-2322 12 2017 7 1 Imaging and mapping the impact of clouds on skyglow with all-sky photometry Andreas Jechow Zoltán Kolláth Salvador J. Ribas Henk Spoelstra Franz Hölker Christopher C. M. Kyba http://orcid.org/0000-0001-7014-1843 Abstract

Artificial skyglow is constantly growing on a global scale, with potential ecological consequences ranging up to affecting biodiversity. To understand these consequences, worldwide mapping of skyglow for all weather conditions is urgently required. In particular, the amplification of skyglow by clouds needs to be studied, as clouds can extend the reach of skyglow into remote areas not affected by light pollution on clear nights. Here we use commercial digital single lens reflex cameras with fisheye lenses for all-sky photometry. We track the reach of skyglow from a peri-urban into a remote area on a clear and a partly cloudy night by performing transects from the Spanish town of Balaguer towards Montsec Astronomical Park. From one single all-sky image, we extract zenith luminance, horizontal and scalar illuminance. While zenith luminance reaches near-natural levels at 5 km distance from the town on the clear night, similar levels are only reached at 27 km on the partly cloudy night. Our results show the dramatic increase of the reach of skyglow even for moderate cloud coverage at this site. The powerful and easy-to-use method promises to be widely applicable for studies of ecological light pollution on a global scale also by non-specialists in photometry.

 07 27 2017 6741 6998 1 10.1007/springer_crossmark_policy link.springer.com false 6 April 2017 22 June 2017 27 July 2017 The authors declare that they have no competing interests. https://creativecommons.org/licenses/by/4.0 https://creativecommons.org/licenses/by/4.0 10.1038/s41598-017-06998-z 20221223082633022 https://www.nature.com/articles/s41598-017-06998-z https://www.nature.com/articles/s41598-017-06998-z.pdf https://www.nature.com/articles/s41598-017-06998-z https://www.nature.com/articles/s41598-017-06998-z.pdf Philosophical Transactions of the Royal Society of London B: Biological Sciences M Aubé 370 20140117 2015 10.1098/rstb.2014.0117 Aubé, M. Physical behaviour of anthropogenic light propagation into the nocturnal environment. Philosophical Transactions of the Royal Society of London B: Biological Sciences 370, 20140117 (2015). Science KW Riegel 179 1285 1973 10.1126/science.179.4080.1285 Riegel, K. W. Light pollution. Science 179, 1285–1291 (1973). Ecology and Society F Hölker 15 4 13 2010 10.5751/ES-03685-150413 Hölker, F. et al. The dark side of light - a transdisciplinary research agenda for light pollution policy. Ecology and Society 15(4), 13 (2010). Energy Environmental Science CCM Kyba 7 1806 2014 10.1039/C4EE00566J Kyba, C. C. M., Hänel, A. & Hölker, F. Redefining efficiency for outdoor lighting. Energy Environmental Science 7, 1806–1809 (2014). Nat Mater P Pust 14 454 2015 10.1038/nmat4270 Pust, P., Schmidt, P. J. & Schnick, W. A revolution in lighting. Nat Mater 14, 454–458 (2015). Philosophical Transactions of the Royal Society of London B: Biological Sciences RG Stevens 370 20140120 2015 10.1098/rstb.2014.0120 Stevens, R. G. & Zhu, Y. Electric light, particularly at night, disrupts human circadian rhythmicity: is that a problem? Philosophical Transactions of the Royal Society of London B: Biological Sciences 370, 20140120 (2015). Rich, C. & Longcore, T. (eds) Ecological Consequences of Artificial Night Lighting (Island Press, Washington, D.C., USA, 2006). Frontiers in Ecology and the Environment T Longcore 2 191 2004 10.1890/1540-9295(2004)002[0191:ELP]2.0.CO;2 Longcore, T. & Rich, C. Ecological light pollution. Frontiers in Ecology and the Environment 2, 191–198 (2004). Royal Society open science M Thums 3 160142 2016 10.1098/rsos.160142 Thums, M. et al. Artificial light on water attracts turtle hatchlings during their near shore transit. Royal Society open science 3, 160142 (2016). Journal of Applied Ecology D Lewanzik 51 388 2014 10.1111/1365-2664.12206 Lewanzik, D. & Voigt, C. C. Artificial light puts ecosystem services of frugivorous bats at risk. Journal of Applied Ecology 51, 388–394 (2014). Journal of Animal Ecology T Degen 85 1352 2016 10.1111/1365-2656.12540 Degen, T. et al. Street lighting: sex-independent impacts on moth movement. Journal of Animal Ecology 85, 1352–1360 (2016). 10.1111/1365-2745.12551 Bennie, J., Davies, T. W., Cruse, D. & Gaston, K. J. Ecological effects of artificial light at night on wild plants. Journal of Ecology (2016). 10.1098/rspb.2016.0813 Somers-Yeates, R. et al. Light pollution is associated with earlier tree budburst across the United Kingdom. In Proceedings of the Royal Society B, vol. 283, 20160813 (The Royal Society, 2016). Phil. Trans. R. Soc. B F Hölker 370 20140130 2015 10.1098/rstb.2014.0130 Hölker, F. et al. Microbial diversity and community respiration in freshwater sediments influenced by artificial light at night. Phil. Trans. R. Soc. B 370, 20140130 (2015). Trends in Ecology and Evolution F Hölker 25 681 2010 10.1016/j.tree.2010.09.007 Hölker, F., Wolter, C., Perkin, E. K. & Tockner, K. Light pollution as a biodiversity threat. Trends in Ecology and Evolution 25, 681–682 (2010). Philosophical Transactions of the Royal Society of London B: Biological Sciences KJ Gaston 370 20140133 2015 10.1098/rstb.2014.0133 Gaston, K. J., Visser, M. E. & Hölker, F. The biological impacts of artificial light at night: the research challenge. Philosophical Transactions of the Royal Society of London B: Biological Sciences 370, 20140133 (2015). Landscape Ecology CCM Kyba 28 1637 2013 10.1007/s10980-013-9936-3 Kyba, C. C. M. & Hölker, F. Do artificially illuminated skies affect biodiversity in nocturnal landscapes? Landscape Ecology 28, 1637–1640 (2013). Verhandlungen der Internatinoalen Vereinigung für Theoretische und Angewandte Limnologie MV Moore 27 779 2000 Moore, M. V., Pierce, S. M., Walsh, H. M., Kvalvik, S. K. & Lim, J. D. Urban light pollution alters the diel vertical migration of daphnia. Verhandlungen der Internatinoalen Vereinigung für Theoretische und Angewandte Limnologie 27, 779–782 (2000). PLOS ONE CCM Kyba 6 e17307 2011 10.1371/journal.pone.0017307 Kyba, C. C. M., Ruhtz, T., Fischer, J. & Hölker, F. Cloud coverage acts as an amplifier for ecological light pollution in urban ecosystems. PLOS ONE 6, e17307 (2011). Monthly Notices of the Royal Astronomical Society CCM Kyba 425 701 2012 10.1111/j.1365-2966.2012.21559.x Kyba, C. C. M., Ruhtz, T., Fischer, J. & Hölker, F. Red is the new black: How the color of urban skyglow varies with cloud cover. Monthly Notices of the Royal Astronomical Society 425, 701–708 (2012). Journal of Quantitative Spectroscopy and Radiative Transfer M Aubé 181 11 2016 10.1016/j.jqsrt.2016.01.032 Aubé, M., Kocifaj, M., Zamorano, J., Solano-Lamphar, H. & de Miguel, A. S. The spectral amplification effect of clouds to the night sky radiance in Madrid. Journal of Quantitative Spectroscopy and Radiative Transfer 181, 11–23 (2016). Journal of Quantitative Spectroscopy and Radiative Transfer A Jechow 181 24 2016 10.1016/j.jqsrt.2016.02.005 Jechow, A., Hölker, F., Kolláth, Z., Gessner, M. O. & Kyba, C. C. M. Evaluating the summer night sky brightness at a research field site on Lake Stechlin in Northeastern Germany. Journal of Quantitative Spectroscopy and Radiative Transfer 181, 24–32 (2016). International Journal of Sustainable Lighting SJ Ribas 35 32 2016 10.26607/ijsl.v18i0.19 Ribas, S. J., Figueras, F., Paricio, S., Canal-Domingo, R. & Torra, J. How clouds are amplifying (or not) the effects of ALAN. International Journal of Sustainable Lighting 35, 32–39 (2016). Monthly Notices of the Royal Astronomical Society M Kocifaj 443 3665 2014 10.1093/mnras/stu1301 Kocifaj, M. & Lamphar, H. A. S. Quantitative analysis of night skyglow amplification under cloudy conditions. Monthly Notices of the Royal Astronomical Society 443, 3665–3674 (2014). The Obs. RH Garstang 127 1 2007 Garstang, R. H. Brightness of clouds at night over a city. The Obs. 127, 1–13 (2007). Scientific Reports M Spitschan 6 26756 2016 10.1038/srep26756 Spitschan, M., Aguirre, G. K., Brainard, D. H. & Sweeney, A. M. Variation of outdoor illumination as a function of solar elevation and light pollution. Scientific Reports 6, 26756 (2016). Bulletin of the American Meteorological Society D Hillger 94 1019 2013 10.1175/BAMS-D-12-00097.1 Hillger, D. et al. First-light imagery from suomi NPP VIIRS. Bulletin of the American Meteorological Society 94, 1019–1029 (2013). Remote Sensing of Environment Y Katz 177 65 2016 10.1016/j.rse.2016.02.017 Katz, Y. & Levin, N. Quantifying urban light pollution — a comparison between field measurements and eros-b imagery. Remote Sensing of Environment 177, 65–77 (2016). Monthly Notices of the Royal Astronomical Society P Cinzano 328 689 2001 10.1046/j.1365-8711.2001.04882.x Cinzano, P., Falchi, F. & Elvidge, C. D. The first World Atlas of the artificial night sky brightness. Monthly Notices of the Royal Astronomical Society 328, 689–707 (2001). Science advances F Falchi 2 e1600377 2016 10.1126/sciadv.1600377 Falchi, F. et al. The new world atlas of artificial night sky brightness. Science advances 2, e1600377 (2016). Remote sensing C Kyba 7 1 2014 10.3390/rs70100001 Kyba, C. et al. High-resolution imagery of earth at night: new sources, opportunities and challenges. Remote sensing 7, 1–23 (2014). Monthly Notices of the Royal Astronomical Society JD Biggs 421 1450 2012 10.1111/j.1365-2966.2012.20416.x Biggs, J. D., Fouché, T., Bilki, F. & Zadnik, M. G. Measuring and mapping the night sky brightness of Perth, Western Australia. Monthly Notices of the Royal Astronomical Society 421, 1450–1464 (2012). 10.1098/rsos.160541 Bará, S. Anthropogenic disruption of the night sky darkness in urban and rural areas. Open Science 3 (2016). Scientific Reports CCM Kyba 5 8409 2015 10.1038/srep08409 Kyba, C. C. M. et al. Worldwide variations in artificial skyglow. Scientific Reports 5, 8409 (2015). International Journal of Sustainable Lighting J Zamorano 35 49 2016 Zamorano, J., García, C., González, R., Tapia, C. & Sánchez de Miguel, A. Stars4all night sky brightness photometer. International Journal of Sustainable Lighting 35, 49–54 (2016). Journal of Quantitative Spectroscopy and Radiative Transfer DM Duriscoe 181 33 2016 10.1016/j.jqsrt.2016.02.022 Duriscoe, D. M. Photometric indicators of visual night sky quality derived from all-sky brightness maps. Journal of Quantitative Spectroscopy and Radiative Transfer 181, 33–45 (2016). Monthly Notices of the Royal Astronomical Society M Kocifaj 446 2895 2015 10.1093/mnras/stu2265 Kocifaj, M., Posch, T. & Lamphar, H. S. On the relation between zenith sky brightness and horizontal illuminance. Monthly Notices of the Royal Astronomical Society 446, 2895–2901 (2015). Revista Mexicana de Astronoma y Astrofsica A Müller 41 46 2011 Müller, A., Wuchterl, G. & Sarazin, M. Measuring the night sky brightness with the lightmeter. Revista Mexicana de Astronoma y Astrofsica 41, 46–49 (2011). Publications of the Astronomical Society of the Pacific J Aceituno 123 1076 2011 10.1086/661918 Aceituno, J. et al. An all-sky transmission monitor: Astmon. Publications of the Astronomical Society of the Pacific 123, 1076 (2011). Journal of Quantitative Spectroscopy and Radiative Transfer J Zamorano 181 52 2016 10.1016/j.jqsrt.2016.02.029 Zamorano, J. et al. Testing sky brightness models against radial dependency: A dense two dimensional survey around the city of madrid, spain. Journal of Quantitative Spectroscopy and Radiative Transfer 181, 52–66 (2016). Publications of the Astronomical Society of the Pacific DM Duriscoe 119 192 2007 10.1086/512069 Duriscoe, D. M., Luginbuhl, C. B. & Moore, C. A. Measuring night-sky brightness with a wide-field CCD camera. Publications of the Astronomical Society of the Pacific 119, 192–213 (2007). Lighting Research & Technology O Rabaza 46 5 2014 10.1177/1477153513510235 Rabaza, O., Aznar-Dols, F., Mercado-Vargas, M. & Espn-Estrella, A. A new method of measuring and monitoring light pollution in the night sky. Lighting Research & Technology 46, 5–19 (2014). Journal of environmental management O Rabaza 91 1278 2010 10.1016/j.jenvman.2010.02.002 Rabaza, O., Galad-Enrquez, D., Estrella, A. E. & Dols, F. A. All-sky brightness monitoring of light pollution with astronomical methods. Journal of environmental management 91, 1278–1287 (2010). Journal of Quantitative Spectroscopy and Radiative Transfer HA Solano-Lamphar 181 87 2016 10.1016/j.jqsrt.2016.04.027 Solano-Lamphar, H. A. & Kocifaj, M. Urban artificial light emission function determined experimentally using night sky images. Journal of Quantitative Spectroscopy and Radiative Transfer 181, 87–95 (2016). 10.2118/158034-MS Pendoley, K. L. et al. A novel technique for monitoring light pollution. In International Conference on Health, Safety and Environment in Oil and Gas Exploration and Production (Society of Petroleum Engineers, 2012). Journal of Physics: Conference Series Z Kolláth 218 012001 2010 Kolláth, Z. Measuring and modelling light pollution at the Zselic starry sky park. Journal of Physics: Conference Series 218, 012001 (2010). s. Monthly Notices of the Royal Astronomical Society M Kocifaj 453 819 2015 10.1093/mnras/stv1645 Kocifaj, M., Solano-Lamphar, H. A. & Kundracik, F. Retrieval of Garstang’s emission function from all-sky camera image. s. Monthly Notices of the Royal Astronomical Society 453, 819–827 (2015). 10.26607/ijsl.v19i1.62 Jechow, A. et al. Measuring light pollution with fisheye lens imagery from a moving boat, a proof of concept. arXiv preprint arxiv:1703.08484 (2017). Current Biology M Dacke 23 298 2013 10.1016/j.cub.2012.12.034 Dacke, M., Baird, E., Byrne, M., Scholtz, C. H. & Warrant, E. J. Dung beetles use the Milky Way for orientation. Current Biology 23, 298–300 (2013). Scientific Reports R Tamir 7 42329 2017 10.1038/srep42329 Tamir, R., Lerner, A., Haspel, C., Dubinsky, Z. & Iluz, D. The spectral and spatial distribution of light pollution in the waters of the northern Gulf of Aqaba (Eilat). Scientific Reports 7, 42329 (2017). ISPRS Journal of Photogrammetry and Remote Sensing R Alamús 124 16 2017 10.1016/j.isprsjprs.2016.12.004 Alamús, R. et al. Ground-based hyperspectral analysis of the urban nightscape. ISPRS Journal of Photogrammetry and Remote Sensing 124, 16–26 (2017). Scientific Reports CCM Kyba 3 1835 2013 10.1038/srep01835 Kyba, C. C. M. et al. Citizen science provides valuable data for monitoring global night sky luminance. Scientific Reports 3, 1835 (2013). Ribas, S. J. et al. Report of the 2016 STARS4ALL/LoNNe Intercomparison Campaign. Tech. Rep., LoNNe, GFZ Potsdam (2017). 10.26607/ijsl.v19i1.70 Kolláth, Z. & Dömény, A. Night sky quality monitoring in existing and planned dark sky parks by digital cameras. arXiv preprint arXiv:1705.09594 (2017). Hänel, A. et al. Measuring night sky brightness: methods and challenges. Submitted to J. of Quant. Spectrosc. and Radiat. Transf. (2017). Kyba, C. et al. Report of the 2015 LoNNe Intercomparison Campaign. Tech. Rep., LoNNe, GFZ Potsdam (2015). Sensors P den Outer 15 9466 2015 10.3390/s150409466 den Outer, P. et al. Stability of the nine sky quality meters in the dutch night sky brightness monitoring network. Sensors 15, 9466–9480 (2015).