Artificial Light at Night (ALAN) Research Literature Database -- Query Results

Levin, N., Kyba, C. C. M., Zhang, Q., Sánchez de Miguel, A., Román, M. O., Li, X., et al. (2020). Remote sensing of night lights: A review and an outlook for the future. Remote Sensing of Environment, 237, In press. Abstract: Remote sensing of night light emissions in the visible band offers a unique opportunity to directly observe human activity from space. This has allowed a host of applications including mapping urban areas, estimating population and GDP, monitoring disasters and conflicts. More recently, remotely sensed night lights data have found use in understanding the environmental impacts of light emissions (light pollution), including their impacts on human health. In this review, we outline the historical development of night-time optical sensors up to the current state of the art sensors, highlight various applications of night light data, discuss the special challenges associated with remote sensing of night lights with a focus on the limitations of current sensors, and provide an outlook for the future of remote sensing of night lights. While the paper mainly focuses on space borne remote sensing, ground based sensing of night-time brightness for studies on astronomical and ecological light pollution, as well as for calibration and validation of space borne data, are also discussed. Although the development of night light sensors lags behind day-time sensors, we demonstrate that the field is in a stage of rapid development. The worldwide transition to LED lights poses a particular challenge for remote sensing of night lights, and strongly highlights the need for a new generation of space borne night lights instruments. This work shows that future sensors are needed to monitor temporal changes during the night (for example from a geostationary platform or constellation of satellites), and to better understand the angular patterns of light emission (roughly analogous to the BRDF in daylight sensing). Perhaps most importantly, we make the case that higher spatial resolution and multispectral sensors covering the range from blue to NIR are needed to more effectively identify lighting technologies, map urban functions, and monitor energy use. Keywords: Remote Sensing http://alandb.darksky.org/show.php?record=2771
Haddock, J. K., Threlfall, C. G., Law, B., & Hochuli, D. F. (2019). Light pollution at the urban forest edge negatively impacts insectivorous bats. Biological Conservation, 236, 17–28. Abstract: Connectivity and quality of vegetation in cities, including urban forests, can promote urban biodiversity. However the impact of anthropogenic pressures at the forest-matrix edge, particularly artificial light at night (ALAN), on connectivity has received little attention. We assessed the influence of artificial light at forest edges on insectivorous bats. We acoustically surveyed 31 forest edges across greater Sydney, Australia, half with mercury vapour streetlights and half in ambient darkness, and compared the bat assemblage and activity levels to urban forest interiors. We also sampled the flying insect community to establish whether changes in insect densities under lights drive changes in insectivorous bat activity. We recorded 9965 bat passes from 16 species or species groups throughout our acoustic survey. The activity of all bats, and bats hypothesised to be sensitive to artificial light, was consistently higher in forest interiors as opposed to edges. We found that slower flying bats adapted to cluttered vegetation or with a relatively high characteristic echolocation call frequency; Chalinolobus morio, Miniopterus australis, Vespadelus vulturnus, and Nyctophilus spp., were negatively affected by artificial light sources at the forest edge. The emergence time of Vespadelus vulturnus was also significantly delayed by the presence of streetlights at the forest edge. Conversely, generalist faster flying bats; Chalinolobus gouldii, Ozimops ridei, Austronomous australis, Saccolaimus flaviventris, and Miniopterus orianae oceanensis, were unaffected by artificial light at the edge of urban forest, and used light and dark forest edges in a similar way. Insect surveys showed that larger lepidopterans seemed to be attracted to lit areas, but in low numbers. Artificial light sources on the edges of urban forest have diverse effects on bats and insects, and should be considered an anthropogenic edge effect that can reduce available habitat and decrease connectivity for light-sensitive species. Keywords: Animals http://alandb.darksky.org/show.php?record=2505
Gong, P., Li, X., Wang, J., Bai, Y., Chen, B., Hu, T., et al. (2020). Annual maps of global artificial impervious area (GAIA) between 1985 and 2018. Remote Sensing of Environment, 236, in press. Abstract: Artificial impervious areas are predominant indicators of human settlements. Timely, accurate, and frequent information on artificial impervious areas is critical to understanding the process of urbanization and land use/cover change, as well as of their impacts on the environment and biodiversity. Despite their importance, there still lack annual maps of high-resolution Global Artificial Impervious Areas (GAIA) with longer than 30-year records, due to the high demand of high performance computation and the lack of effective mapping algorithms. In this paper, we mapped annual GAIA from 1985 to 2018 using the full archive of 30-m resolution Landsat images on the Google Earth Engine platform. With ancillary datasets, including the nighttime light data and the Sentinel-1 Synthetic Aperture Radar data, we improved the performance of our previously developed algorithm in arid areas. We evaluated the GAIA data for 1985, 1990, 1995, 2000, 2005, 2010, and 2015, and the mean overall accuracy is higher than 90%. A cross-product comparison indicates the GAIA data are the only dataset spanning over 30 years. The temporal trend in GAIA agrees well with other datasets at the local, regional, and global scales. Our results indicate that the GAIA reached 797,076 km2 in 2018, which is 1.5 times more than that in 1990. China and the United States (US) rank among the top two in artificial impervious area, accounting for approximately 50% of the world's total in 2018. The artificial impervious area of China surpassed that of the US in 2015. By 2018, the remaining eight among the top ten countries are India, Russia, Brazil, France, Italy, Germany, Japan, and Canada. The GAIA dataset can be freely downloaded from http://data.ess.tsinghua.edu.cn. Keywords: Remote Sensing http://alandb.darksky.org/show.php?record=2756
Kotarba, A. Z., Chacewicz, S., & Żmudzka, E. (2019). Night sky photometry over Warsaw (Poland) evaluated simultaneously with surface-based and satellite-based cloud observations. Journal of Quantitative Spectroscopy and Radiative Transfer, 235, 95–107. Abstract: Light pollution is a widely distributed form of anthropogenic pollution that threatens both biodiversity and human health. One of the most popular indicators is known as night sky brightness (NSB), measured with photometric techniques. In the study, we report results of the very first, long-term photometric survey of NSB over Poland's capital, Warsaw, for 636 nights between 2014 and 2016 using a sky quality meter (SQM). Data were collected for all-weather conditions and, for the first time, we simultaneously use two independent sources of cloud amount data: surface-based (SYNOP) and satellite-based (Meteosat/SEVIRI). Results show that Warsaw is significantly polluted by light, with average NSB of 18.65 ± 0.06 magSQM/arcsec2 (15 times higher than unpolluted sky). Zenithal NSB is almost unaffected by moonlight. During astronomical nights, cloud cover was the dominant determinant of NSB, increasing by 7 times for overcast sky. In general, the sky brightened by ∼0.2 magSQM/arcsec2 for each 10% increase in cloud fraction. Satellite-based cloud amount data was found to be a very reliable alternative to traditional SYNOP observations. No statistically significant difference was found for average NSB calculated using satellite and SYNOP datasets. This finding is of particular importance, since the coverage of surface-based data is limited, while satellite observations can be obtained for any location on Earth, and collocate with any NSB photometric station. Our investigation also highlighted that SYNOP data are unreliable when cloud amount is low. This is due to the different fields of view for SQM (20°) and SYNOP (180°) observations of broken cloud. Keywords: Skyglow http://alandb.darksky.org/show.php?record=2580
Rebke, M., Dierschke, V., Weiner, C. N., Aumüller, R., Hill, K., & Hill, R. (2019). Attraction of nocturnally migrating birds to artificial light: The influence of colour, intensity and blinking mode under different cloud cover conditions. Biological Conservation, 233, 220–227. Abstract: A growing number of offshore wind farms have led to a tremendous increase in artificial lighting in the marine environment. This study disentangles the connection of light characteristics, which potentially influence the reaction of nocturnally migrating passerines to artificial illumination under different cloud cover conditions. In a spotlight experiment on a North Sea island, birds were exposed to combinations of light colour (red, yellow, green, blue, white), intensity (half, full) and blinking mode (intermittent, continuous) while measuring their number close to the light source with thermal imaging cameras. We found that no light variant was constantly avoided by nocturnally migrating passerines crossing the sea. The number of birds did neither differ between observation periods with blinking light of different colours nor compared to darkness. While intensity did not influence the number attracted, birds were drawn more towards continuous than towards blinking illumination, when stars were not visible. Red continuous light was the only exception that did not differ from the blinking counterpart. Continuous green, blue and white light attracted significantly more birds than continuous red light in overcast situations. Our results suggest that light sources offshore should be restricted to a minimum, but if lighting is needed, blinking light is to be preferred over continuous light, and if continuous light is required, red light should be applied. Keywords: Animals http://alandb.darksky.org/show.php?record=2255

Levin, N., Kyba, C. C. M., Zhang, Q., Sánchez de Miguel, A., Román, M. O., Li, X., et al. (2020). Remote sensing of night lights: A review and an outlook for the future. Remote Sensing of Environment, 237, In press.

Abstract: Remote sensing of night light emissions in the visible band offers a unique opportunity to directly observe human activity from space. This has allowed a host of applications including mapping urban areas, estimating population and GDP, monitoring disasters and conflicts. More recently, remotely sensed night lights data have found use in understanding the environmental impacts of light emissions (light pollution), including their impacts on human health. In this review, we outline the historical development of night-time optical sensors up to the current state of the art sensors, highlight various applications of night light data, discuss the special challenges associated with remote sensing of night lights with a focus on the limitations of current sensors, and provide an outlook for the future of remote sensing of night lights. While the paper mainly focuses on space borne remote sensing, ground based sensing of night-time brightness for studies on astronomical and ecological light pollution, as well as for calibration and validation of space borne data, are also discussed. Although the development of night light sensors lags behind day-time sensors, we demonstrate that the field is in a stage of rapid development. The worldwide transition to LED lights poses a particular challenge for remote sensing of night lights, and strongly highlights the need for a new generation of space borne night lights instruments. This work shows that future sensors are needed to monitor temporal changes during the night (for example from a geostationary platform or constellation of satellites), and to better understand the angular patterns of light emission (roughly analogous to the BRDF in daylight sensing). Perhaps most importantly, we make the case that higher spatial resolution and multispectral sensors covering the range from blue to NIR are needed to more effectively identify lighting technologies, map urban functions, and monitor energy use.

Keywords: Remote Sensing

http://alandb.darksky.org/show.php?record=2771

Haddock, J. K., Threlfall, C. G., Law, B., & Hochuli, D. F. (2019). Light pollution at the urban forest edge negatively impacts insectivorous bats. Biological Conservation, 236, 17–28.

Abstract: Connectivity and quality of vegetation in cities, including urban forests, can promote urban biodiversity. However the impact of anthropogenic pressures at the forest-matrix edge, particularly artificial light at night (ALAN), on connectivity has received little attention. We assessed the influence of artificial light at forest edges on insectivorous bats. We acoustically surveyed 31 forest edges across greater Sydney, Australia, half with mercury vapour streetlights and half in ambient darkness, and compared the bat assemblage and activity levels to urban forest interiors. We also sampled the flying insect community to establish whether changes in insect densities under lights drive changes in insectivorous bat activity. We recorded 9965 bat passes from 16 species or species groups throughout our acoustic survey. The activity of all bats, and bats hypothesised to be sensitive to artificial light, was consistently higher in forest interiors as opposed to edges. We found that slower flying bats adapted to cluttered vegetation or with a relatively high characteristic echolocation call frequency; Chalinolobus morio, Miniopterus australis, Vespadelus vulturnus, and Nyctophilus spp., were negatively affected by artificial light sources at the forest edge. The emergence time of Vespadelus vulturnus was also significantly delayed by the presence of streetlights at the forest edge. Conversely, generalist faster flying bats; Chalinolobus gouldii, Ozimops ridei, Austronomous australis, Saccolaimus flaviventris, and Miniopterus orianae oceanensis, were unaffected by artificial light at the edge of urban forest, and used light and dark forest edges in a similar way. Insect surveys showed that larger lepidopterans seemed to be attracted to lit areas, but in low numbers. Artificial light sources on the edges of urban forest have diverse effects on bats and insects, and should be considered an anthropogenic edge effect that can reduce available habitat and decrease connectivity for light-sensitive species.

Keywords: Animals

http://alandb.darksky.org/show.php?record=2505

Gong, P., Li, X., Wang, J., Bai, Y., Chen, B., Hu, T., et al. (2020). Annual maps of global artificial impervious area (GAIA) between 1985 and 2018. Remote Sensing of Environment, 236, in press.

Kotarba, A. Z., Chacewicz, S., & Żmudzka, E. (2019). Night sky photometry over Warsaw (Poland) evaluated simultaneously with surface-based and satellite-based cloud observations. Journal of Quantitative Spectroscopy and Radiative Transfer, 235, 95–107.

Rebke, M., Dierschke, V., Weiner, C. N., Aumüller, R., Hill, K., & Hill, R. (2019). Attraction of nocturnally migrating birds to artificial light: The influence of colour, intensity and blinking mode under different cloud cover conditions. Biological Conservation, 233, 220–227.