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Author Sutton, P.C.
Title A scale-adjusted measure of “Urban sprawl” using nighttime satellite imagery Type Journal Article
Year 2003 Publication Remote Sensing of Environment Abbreviated Journal Remote Sensing of Environment
Volume 86 Issue 3 Pages 353-369
Keywords Urban sprawl; Sprawl Line; Nighttime satellite imagery; DMSP-OLS; remote sensing; satellite; llight at night
Abstract “Urban Sprawl” is a growing concern of citizens, environmental organizations, and governments. Negative impacts often attributed to urban sprawl are traffic congestion, loss of open space, and increased pollutant runoff into natural waterways. Definitions of “Urban Sprawl” range from local patterns of land use and development to aggregate measures of per capita land consumption for given contiguous urban areas (UA). This research creates a measure of per capita land use consumption as an aggregate index for the spatially contiguous urban areas of the conterminous United States with population of 50,000 or greater. Nighttime satellite imagery obtained by the Defense Meteorological Satellite Program's Operational Linescan System (DMSP OLS) is used as a proxy measure of urban extent. The corresponding population of these urban areas is derived from a grid of the block group level data from the 1990 U.S. Census. These numbers are used to develop a regression equation between Ln(Urban Area) and Ln(Urban Population). The ‘scale-adjustment’ mentioned in the title characterizes the “Urban Sprawl” of each of the urban areas by how far above or below they are on the “Sprawl Line” determined by this regression. This “Sprawl Line” allows for a more fair comparison of “Urban Sprawl” between larger and smaller metropolitan areas because a simple measure of per capita land consumption or population density does not account for the natural increase in aggregate population density that occurs as cities grow in population. Cities that have more “Urban Sprawl” by this measure tended to be inland and Midwestern cities such as Minneapolis–St. Paul, Atlanta, Dallas–Ft. Worth, St. Louis, and Kansas City. Surprisingly, west coast cities including Los Angeles had some of the lowest levels of “Urban Sprawl” by this measure. There were many low light levels seen in the nighttime imagery around these major urban areas that were not included in either of the two definitions of urban extent used in this study. These areas may represent a growing commuter-shed of urban workers who do not live in the urban core but nonetheless contribute to many of the impacts typically attributed to “Urban Sprawl”. “Urban Sprawl” is difficult to define precisely partly because public perception of sprawl is likely derived from local land use planning decisions, spatio-demographic change in growing urban areas, and changing values and social mores resulting from differential rates of international migration to the urban areas of the United States. Nonetheless, the aggregate measures derived here are somewhat different than similar previously used measures in that they are ‘scale-adjusted’; also, the spatial patterns of “Urban Sprawl” shown here shed some insight and raise interesting questions about how the dynamics of “Urban Sprawl” are changing.
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Series Editor Series Title (up) Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0034-4257 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 233
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Author Sutton, P.; Roberts, D.; Elvidge, C.; Baugh, K.
Title Census from Heaven: An estimate of the global human population using night-time satellite imagery Type Journal Article
Year 2001 Publication International Journal of Remote Sensing Abbreviated Journal International Journal of Remote Sensing
Volume 22 Issue 16 Pages 3061-3076
Keywords light at night; DMSP-OLS; remote sensing; satellite
Abstract Night-time satellite imagery provided by the Defense Meteorological Satellite Program's Operational Linescan System (DMSP OLS) is evaluated as a means of estimating the population of all the cities of the world based on their areal extent in the image. A global night-time image product was registered to a dataset of 2000 known city locations with known populations. A relationship between areal extent and city population discovered by Tobler and Nordbeck is identified on a nation by nation basis to estimate the population of the 22 920 urban clusters that exist in the night-time satellite image. The relationship between city population and city areal extent was derived from 1597 city point locations with known population that landed in a 'lit' area of the image. Due to conurbation, these 1597 cities resulted in only 1383 points of analysis for performing regression. When several cities fell into one 'lit' area their populations were summed. The results of this analysis allow for an estimate of the urban population of every nation of the world. By using the known percent of population in urban areas for every nation a total national population was also estimated. The sum of these estimates is a total estimate of the global human population, which in this case was 6.3 billion. This is fairly close to the generally accepted contemporaneous (1997) estimate of the global population which stood at approximately 5.9 billion.
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Series Editor Series Title (up) Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0143-1161 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 234
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Author Warrant, E.J.; Johnsen, S.
Title Vision and the light environment Type Journal Article
Year 2013 Publication Current Biology : CB Abbreviated Journal Curr Biol
Volume 23 Issue 22 Pages R990-4
Keywords photobiology; animals; physiology of vision; photodetection
Abstract Almost all animals, no matter how humble, possess eyes. Only those that live in total darkness, such as in a pitch-dark cave, may lack eyes entirely. Even at tremendous depths in the ocean — where the only lights that are ever seen are rare and fitful sparks of bioluminescence — most animals have eyes, and often surprisingly well-developed eyes. And despite their diversity (there are currently ten generally recognised optical types) all eyes have evolved in response to the remarkably varied light environments that are present in the habitats where animals live. Variations in the intensity of light, as well as in its direction, colour and dominant planes of polarisation, have all had dramatic effects on visual evolution. In the terrestrial habitats where we ourselves have most recently evolved, the light environment can vary quite markedly from day to night and from one location to another. In aquatic habitats, this variation can be orders of magnitude greater. Even though the ecologies and life histories of animals have played a major role in visual evolution, it is arguably the physical limitations imposed on photodetection by a given habitat and its light environment that have defined the basic selective pressures that have driven the evolution of eyes.
Address Department of Biology, University of Lund, Solvegatan 35, S-22362 Lund, Sweden. Electronic address: Eric.Warrant@biol.lu.se
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Series Volume Series Issue Edition
ISSN 0960-9822 ISBN Medium
Area Expedition Conference
Notes PMID:24262832 Approved no
Call Number IDA @ john @ Serial 235
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Author Meng, Y.; He, Z.; Yin, J.; Zhang, Y.; Zhang, T.
Title Quantitative calculation of human melatonin suppression induced by inappropriate light at night Type Journal Article
Year 2011 Publication Medical & Biological Engineering & Computing Abbreviated Journal Med Biol Eng Comput
Volume 49 Issue 9 Pages 1083-1088
Keywords Algorithms; Circadian Rhythm/physiology/*radiation effects; Humans; *Lighting; Melatonin/*secretion; *Models, Biological; Retinal Cone Photoreceptor Cells/physiology/radiation effects; Retinal Ganglion Cells/physiology/radiation effects; Retinal Rod Photoreceptor Cells/physiology/radiation effects
Abstract Melatonin (C(1)(3)H(1)(6)N(2)O(2)) has a wide range of functions in the body. When is inappropriately exposed to light at night, human circadian rhythm will be interfered and then melatonin secretion will become abnormal. For nearly three decades great progresses have been achieved in analytic action spectra and melatonin suppression by various light conditions. However, so far few articles focused on the quantitative calculation of melatonin suppression induced by light. In this article, an algorithm is established, in which all the contributions of rods, cones, and intrinsically photosensitive retinal ganglion cells are considered. Calculation results accords with the experimental data in references very well, which indicate the validity of this algorithm. This algorithm can also interpret the rule of melatonin suppression varying with light correlated color temperature very well.
Address Photonics Research Center, School of Physics, Nankai University, Tianjin 300071, China
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Series Volume Series Issue Edition
ISSN 0140-0118 ISBN Medium
Area Expedition Conference
Notes PMID:21717231 Approved no
Call Number IDA @ john @ Serial 236
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Author Inger, R.; Bennie, J.; Davies, T.W.; Gaston, K.J.
Title Potential biological and ecological effects of flickering artificial light Type Journal Article
Year 2014 Publication PloS one Abbreviated Journal PLoS One
Volume 9 Issue 5 Pages e98631
Keywords flickering; artificial light; biology
Abstract Organisms have evolved under stable natural lighting regimes, employing cues from these to govern key ecological processes. However, the extent and density of artificial lighting within the environment has increased recently, causing widespread alteration of these regimes. Indeed, night-time electric lighting is known significantly to disrupt phenology, behaviour, and reproductive success, and thence community composition and ecosystem functioning. Until now, most attention has focussed on effects of the occurrence, timing, and spectral composition of artificial lighting. Little considered is that many types of lamp do not produce a constant stream of light but a series of pulses. This flickering light has been shown to have detrimental effects in humans and other species. Whether a species is likely to be affected will largely be determined by its visual temporal resolution, measured as the critical fusion frequency. That is the frequency at which a series of light pulses are perceived as a constant stream. Here we use the largest collation to date of critical fusion frequencies, across a broad range of taxa, to demonstrate that a significant proportion of species can detect such flicker in widely used lamps. Flickering artificial light thus has marked potential to produce ecological effects that have not previously been considered.
Address Environment and Sustainability Institute, University of Exeter, Penryn, Cornwall, United Kingdom
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Language English Summary Language Original Title
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ISSN 1932-6203 ISBN Medium
Area Expedition Conference
Notes PMID:24874801; PMCID:PMC4038456 Approved no
Call Number IDA @ john @ Serial 237
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