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Bará, S., Rodríguez-Arós, Á., Pérez, M., Tosar, B., Lima, R., Sánchez de Miguel, A., et al. (2018). Estimating the relative contribution of streetlights, vehicles, and residential lighting to the urban night sky brightness. Lighting Res & Tech, (October 2018).
Abstract: Under stable atmospheric conditions the brightness of the urban sky varies throughout the night following the time course of the anthropogenic emissions of light. Different types of artificial light sources (e.g. streetlights, residential, and vehicle lights) have specific time signatures, and this feature makes it possible to estimate the amount of brightness contributed by each of them. Our approach is based on transforming the time representation of the zenithal night sky brightness into a modal expansion in terms of the time signatures of the different sources of light. The modal coefficients, and hence the absolute and relative contributions of each type of source, can be estimated by means of a linear least squares fit. A practical method for determining the time signatures of different contributing sources is also described, based on wide-field time-lapse photometry of the urban nightscape. Our preliminary results suggest that, besides the dominant streetlight contribution, artificial light leaking out of the windows of residential buildings may account for a significant share of the time-varying part of the zenithal night sky brightness at the measurement locations, whilst the contribution of the vehicle lights seems to be significantly smaller.
Keywords: Remote Sensing; traffic; Roadway lighting
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Bará, S., Tilve, V., Nievas, M., Sanchez de Miguel, A., & Zamorano, J. (2015). Zernike power spectra of clear and cloudy light-polluted urban night skies. Appl. Opt., 54(13), 4120–4129.
Abstract: The Zernike power spectra of the all-sky night brightness distributions of clear and cloudy nights are computed using a modal projection approach. The results obtained in the B, V and R Johnson-Cousins' photometric bands during a one-year campaign of observations at a light-polluted urban site show that these spectra can be described by simple power laws with exponents close to -3 for clear nights and -2 for cloudy ones. The second-moment matrices of the Zernike coefficients show relevant correlations between modes. The multiplicative role of the cloud cover, that contributes to a significant increase of the brightness of the urban night sky in comparison with the values obtained in clear nights, is described in the Zernike space.
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Bashiri, F., & Hassan, C. R. C. (2014). Light Pollution and Its Effect on the Environment. Intl. J. of Fundamental Phys. Sci., 4(1), 8–12.
Abstract: Light pollution can cause disturbance to humans as well as animals. The aim of this study is to determine the effect of light pollution on human's health, plants, animals, human body and People’s attitude about light pollution. About 90% of people strongly agreed that excessive lighting has adverse effects on a person's health. At least, 70% of people had difficulty in sleeping because of light pollution. Most of people believed that video Billboards, Spotlights, Car headlights and Street lights are the most important source of light pollution and about 60% of people agree that light pollution can affect animal’s sleep. 60% of people believed that excessive artificial light can attract several kinks of birds and insects. The results of this study indicate that the human health, plants growth and animal behaviour are strongly affected by the light pollution.‎
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Bauer, S. E., Wagner, S. E., Burch, J., Bayakly, R., & Vena, J. E. (2013). A case-referent study: light at night and breast cancer risk in Georgia. Int J Health Geogr, 12, 23.
Abstract: BACKGROUND: Literature has identified detrimental health effects from the indiscriminate use of artificial nighttime light. We examined the co-distribution of light at night (LAN) and breast cancer (BC) incidence in Georgia, with the goal to contribute to the accumulating evidence that exposure to LAN increases risk of BC. METHODS: Using Georgia Comprehensive Cancer Registry data (2000-2007), we conducted a case-referent study among 34,053 BC cases and 14,458 lung cancer referents. Individuals with lung cancer were used as referents to control for other cancer risk factors that may be associated with elevated LAN, such as air pollution, and since this cancer type was not previously associated with LAN or circadian rhythm disruption. DMSP-OLS Nighttime Light Time Series satellite images (1992-2007) were used to estimate LAN levels; low (0-20 watts per sterradian cm(2)), medium (21-41 watts per sterradian cm(2)), high (>41 watts per sterradian cm(2)). LAN levels were extracted for each year of exposure prior to case/referent diagnosis in ArcGIS. RESULTS: Odds ratios (OR) and 95% confidence intervals (CI) were estimated using logistic regression models controlling for individual-level year of diagnosis, race, age at diagnosis, tumor grade, stage; and population-level determinants including metropolitan statistical area (MSA) status, births per 1,000 women aged 15-50, percentage of female smokers, MSA population mobility, and percentage of population over 16 in the labor force. We found that overall BC incidence was associated with high LAN exposure (OR = 1.12, 95% CI [1.04, 1.20]). When stratified by race, LAN exposure was associated with increased BC risk among whites (OR = 1.13, 95% CI [1.05, 1.22]), but not among blacks (OR = 1.02, 95% CI [0.82, 1.28]). CONCLUSIONS: Our results suggest positive associations between LAN and BC incidence, especially among whites. The consistency of our findings with previous studies suggests that there could be fundamental biological links between exposure to artificial LAN and increased BC incidence, although additional research using exposure metrics at the individual level is required to confirm or refute these findings.
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Baugh, K., Hsu, F. - C., Elvidge, C. D., & Zhizhin, M. (2013). Nighttime Lights Compositing Using the VIIRS Day-Night Band: Preliminary Results. APAN Proceedings, 35, 70.
Abstract: Dramatically improved nighttime lights capabilities are presented by the launch of the National Polar-orbiting Partnership (NPP) Visible Infrared Imaging Radiometer Suite (VIIRS) Day Night Band (DNB) sensor. Building on 18 years of experience compositing nighttime data from the Defense Meteorological Satellite Program (DMSP) Operational Linescan System (OLS), NOAA’s NGDC Earth Observation Group has started adapting their algorithms to process these new data. The concept of compositing nighttime data comprises combining only high quality data components over a period of time to improve sensitivity and coverage. For this work, flag image are compiled to describe image quality. The flag categories include: daytime, twilight, stray light, lunar illuminance, noisy edge of scan data, clouds, and no data. High quality data is defined as not having any of these attributes present. Two methods of reprojection are necessary due to data collection characteristics. Custom algorithms have been created to terrain-correct and reproject all data to a common 15 arc second grid. Results of compositing over two time periods in 2012 are presented to demonstrate data quality and initial capabilities. These data can be downloaded at http://www.ngdc.noaa.gov/eog/viirs/downloadviirsntl.html.
Keywords: remote sensing; light pollution; VIIRS; satellite; radiometry
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