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HomeMy WebLinkAbout04-11-21 Public Comment - J. Seymour - Lighting Code VarianceFrom:Joseph D. Seymour To:Agenda Subject:Lighting Variances Date:Sunday, April 11, 2021 10:46:03 AM Attachments:science362_744_environmentallight_gaston.pdf CAUTION: This email originated from outside of the organization. Do not click links or open attachments unless you recognize the sender and know the content is safe. I am writing to urge the City Commission to deny a variance from lighting codes for alldevelopments and specifically for the development at College and Main/Huffine. As indicated in the attached paper, the scientific research is clear that over lighting and certain colors(wavelengths) of light are highly disruptive to both humans and animals. Preserve the natural Montana environment for people and wildlife and decrease lighting intensity and density,while utilizing wavelength emission spectra that are less disruptive and shrouds to direct light. Joseph D. Seymour Ph.D. Chem. Eng. sciencemag.org SCIENCE PHOTO: NASA, SCOTT KELLY By Kevin J. Gaston A mong the most visually compelling images of the whole Earth have been those created using data obtained at night by astronauts or from sat- ellites. The proliferation in use of electric lighting—including from industrial, commercial, municipal, and do- mestic sources—is striking. It sketches the spatial distribution of much of the human population, outlining a substantial propor- tion of the world’s coastline, highlighting a multitude of towns and cities, and drawing the major highways that connect them. The data embodied in these nighttime images have been used to estimate and map levels of energy use, urbanization, and economic activity. They have also been key in focus- ing attention on the environmental impacts of the artificial light at night itself. Explicit steps need to be taken to limit these im- pacts, which vary according to the intensity, spectrum, spatial extent, and temporal dy- namics of this lighting. FROM DIRECT LIGHT TO SKYGLOW Artificial light at night can usefully be thought of as having two linked components. The first component—direct emissions from outdoor lighting sources, which include streetlights, building and infrastructure lighting, and road vehicle headlamps—is spa- tially extremely heterogeneous. Ground-level illuminance in the immediate vicinity can vary from less than 10 lux (lx) to more than 100 lx (for context, a full moon on a clear night has an illuminance of up to 0.1 lx). It often declines rapidly over distances of a few meters. However, emissions from unshielded lights can, when unobstructed, carry horizon- tally over many kilometers, making artificial light at night both an urban and a rural issue. The second component of artificial light at night is skyglow, the brightening of the night- time sky caused mainly by upwardly emitted and reflected artificial light that is scattered in the atmosphere by water, dust, and gas molecules. Although absolute illuminance levels are at most about 0.2 to 0.5 lx, much lower than those from direct emissions, these are often sufficiently high to obscure the Milky Way, which is used for orientation by some organisms. In many urban areas, sky- glow even obscures lunar light cycles, which are used by many organisms as cues for bio- logical activity. CONSERVATION Lighting up the nighttime Artificial light at night needs to be reduced to limit negative environmental impacts Environment and Sustainability Institute, University of Exeter, Penryn, Cornwall TR10 9FE, UK. Email: k.j.gaston@exeter.ac.uk INSIGHTS PERSPECTIVES 744 16 NOVEMBER 2018 • VOL 362 ISSUE 6416 Published by AAAS on April 11, 2021 http://science.sciencemag.org/Downloaded from SCIENCE sciencemag.org In the laboratory, organismal responses, such as suppression of melatonin levels and changes to behavioral activity patterns, gener- ally increase with greater intensities of artifi- cial light at night. It is challenging to establish the form of such functional relationships in the field, but experiments and observations have shown that commonplace levels of artifi- cial light at night influence a wide range of bi- ological phenomena across a wide diversity of taxa, including individual physiology and be- havior, species abundances and distributions, community structure and dynamics, and eco- system function and process (1). Exposure to even dim nighttime lighting (below 1 lx) can drastically change activity patterns of both naturally day-active and night-active species. These effects can be exacerbated by trophic interactions, such that the abundances of spe- cies whose activity is not directly altered may nonetheless be severely affected under low levels of nighttime lighting (2). SHIFTING SPECTRA Globally, the prevailing technology of out- door lighting is undergoing a marked shift to light-emitting diodes (LEDs). Although LEDs can be used to produce a wide di- versity of emission spectra, the main trend has been for narrower-spectrum street lighting with lower (“warmer”) correlated color temperature (CCT) to be replaced by broader-spectrum LED lamps with higher (“cool white”) CCT. This lighting provides improved color rendering, more faithfully revealing colors as seen under sunlight, but also tends to exacerbate skyglow unless accompanied by dimming and improved shielding (3). Biological responses to light are almost invariably spectrum-dependent, and broadening the spectrum of emissions increases the likelihood of their overlapping with these patterns of sensitivity, often in- creasing the biological impact. Of particular concern is the growth in emissions of blue wavelengths, to which melatonin suppression is disproportionately sensitive. Multiple cascading processes can include stress responses, disease risk, and likelihood of obesity. Medical organizations have advised that poorly designed high- intensity and high-CCT street lighting should be avoided to minimize potential harm to human sleep patterns, sleep quality, and cir- cadian rhythms (4). Studies have also raised concerns that greater exposure to artificial light at night increases some cancer risks (5). However, it is difficult to isolate effects of out- door lighting from those of indoor lighting (including the trespass of outdoor lighting indoors) and to adequately control for other risk factors to human health. Concerted ef- fort needs to be invested in assessing the existing evidence for such impacts both in principle and practice, and to find improved methods for measuring these impacts. SPATIAL PATTERNS The global importance of the impacts of ar- tificial light at night rests in large part on its spatial extent. The direct footprint of light emissions is hard to estimate, being heavily dependent on the spatial resolution of avail- able data. According to the best estimates, this extent is increasing at about 2% per year, with growth in the intensity of lighting from already lit areas occurring at a similar rate (6). The reduced operational costs of using LED lamps seem to have encouraged the in- stallation of yet more lighting, rather than savings on preexisting lighting needs. Conservatively, the overall coverage by skyglow is now nearly one-fourth of global land area, with 83% of the human popu- lation estimated to be living under light- polluted skies (7). Skyglow can extend hundreds of kilometers from urban sources, changing the nighttime environment in places that may be protected from many other anthropogenic pressures. Yet those persons responsible for these distant effects rarely recognize their role in creating them, nor are they held accountable. Understanding of landscape-scale impacts of artificial light at night is in its infancy. Nonetheless, there is evidence that the attrac- tion of nighttime-migrating birds to artificial light sources has strong negative impacts on their routes, their stopover habitat selection, and likely their energetics (8, 9). Artificial light at night is also suspected to have played a role in catastrophic region-wide declines in insect populations. Although categori- cal evidence remains wanting, those species of moths that would seem most vulnerable, such as those attracted to lights or that are night-active, have been shown to have experi- enced the greatest losses (10). CHANGING NIGHTTIME LIGHT PATTERNS Artificial lighting truncates the duration of darkness attained in lit areas. Stationary and mobile (e.g., vehicle headlamp) sources tend to be switched on around the onset of dusk, decline to some degree as nighttime progresses (with some stationary lights be- ing switched off and traffic levels declining), and continue until around the conclusion of dawn. As a consequence, the sky over urban areas often becomes somewhat darker as night progresses, whereas in nearby rural lo- cations the sky becomes brighter as the Moon rises and darker as it sets (11). Given the vital role of natural light cycles as cues for daily and seasonal timings of biological activities, it is unsurprising that these changes wrought by artificial light at night can alter those timings (12). This applies not only to animals. For example, artificial light at night has been found to ad- vance the timing of budburst in temperate trees by several days (13). The magnitude of such changes can be similar to those caused by climate change, raising questions as to how the effects of climate change and artifi- cial nighttime lighting interact. REDUCING THE IMPACTS OF ARTIFICIAL LIGHT Given the apparent pervasiveness of the negative biological impacts of artificial light at night, it is vital that these be reduced. Lag effects are common to many anthropogenic pressures on the environment. For example, even if levels of CO2 emissions were to be dramatically reduced, Earth would continue to warm. However, such lags seem much less likely for the effects of artificial light at night. Reductions in artificial light at night would not result in instant recovery, but such recov- ery could be relatively swift. Limiting the use of artificial light at night to the places, times, and forms required to ensure that people can use the nighttime appropriately would enable drastic reduc- tions in artificial light at night in much of the world. Artificial light at night brings tangible benefits to people, most notably in extend- ing the time available for work and social activities. However, existing regulations and requirements of lighting focusing on issues of safety and security are seldom supported by robust empirical evidence (14). To reduce the negative effects of artificial light at night requires a blend of common sense and exploitation of technology. First, artificial light at night should not casually be introduced into areas in which it has not previously occurred, especially in those regions in which naturally dark spaces are now scarce (e.g., Western Europe, the eastern United States, East Asia). Second, lighting should be at the lowest realistic intensity. The environmental im- pacts and energy costs of artificial light at night could be much reduced if emissions were cut to the low levels already used in some cities (e.g., Berlin). Third, outdoor sources should be designed to ensure that lighting is limited to the places where it is actually required; many of the problems caused by artificial light at night result from poor lighting design, especially inadequate shielding. To date, attention here has fallen foremost on improved shielding of streetlights, which are often funded from the public purse. However, attention also needs The bright lights of Tokyo and other cities in Japan, photographed from the International Space Station in 2015, show the proliferation of artificial light on our planet. 16 NOVEMBER 2018 • VOL 362 ISSUE 6416 745 Published by AAAS on April 11, 2021 http://science.sciencemag.org/Downloaded from INSIGHTS | PERSPECTIVES sciencemag.org SCIENCE to be paid to the impacts of other major lo- cal contributors to artificial light at night, in- cluding gas stations, parking lots, transport hubs, sports stadiums, and billboards. Fourth, lighting should only be used at times when it is required; most outdoor light- ing should routinely be dimmed or switched off during periods of low demand. Although, despite energy savings, the costs of smart technologies remain limiting, these can assist in assessing needs and modifying lighting levels accordingly. Finally, a more nuanced approach needs to be taken with regard to the spectrum of lighting, with preferential use of lower-CCT (<2400 K) and thus environmentally less disruptive lamps. Near environmentally sen- sitive zones (e.g., around protected areas, around otherwise dark habitat corridors), only narrow-spectrum lighting should be used, if lighting is needed at all. Use of dim- mer and warm white or amber lighting along rural roads and in residential areas would help to reduce impacts, even if brighter and higher-CCT lighting is used in areas with heavier nighttime use by people and at busy road junctions. The present trend toward widespread introduction of high-CCT light- ing (4000 K) brings major negative envi- ronmental impacts, relative to lower-CCT lighting, for no obvious benefit. The ongoing and planned modernization of public lighting systems in many regions of the world provides a vital and ready oppor- tunity to reduce the environmental impacts of artificial light at night. It could also facili- tate the establishment of new norms that can help to shape future developments (includ- ing in regions that currently have no or little urbanization) that otherwise have enormous potential to further erode the nighttime, such as the inevitable growth in off-grid lighting schemes. Future nighttime images of Earth need not be records of further progression to- ward loss of the nighttime and its benefits. j REFERENCES 1. K. J. Gaston et al., Biol. Rev. 88, 912 (2013). 2. D. Sanders et al., Curr. Biol. 28, 2474 (2018). 3. M. Aubé, Philos. Trans. R. Soc. B 370, 20140117 (2015). 4. American Medical Association, “AMA Adopts Guidance to Reduce Harm from High Intensity Street Lights” (2016); www.ama-assn.org/ama-adopts-guidance-reduce-harm- high-intensity-street-lights. 5. A. Garcia-Saenz et al., Environ. Health Persp. 126, 047011 (2018). 6. C. C. M. Kyba et al., Sci. Adv. 3, e1701528 (2017). 7. F. Falchi et al., Sci. Adv. 2, e1600377 (2016). 8. F. A. La Sorte et al., Glob. Change Biol. 23, 4609 (2017). 9. B. M. Van Doren et al., Proc. Natl. Acad. Sci. U.S.A. 114, 11175 (2017). 10. F. van Langevelde et al., Glob. Change Biol. 24, 925 (2018). 11. C. C. M. Kyba et al., Sci. Rep. 5, 8409 (2015). 12. K. J. Gaston et al., Annu. Rev. Ecol. Evol. Syst. 48, 49 (2017). 13. R. H. ffrench-Constant et al., Proc. R. Soc. B 283, 20160813 (2016). 14. S. Fotios, R. Gibbons, Lighting Res. Technol. 50, 154 (2018). 10.1126/science.aau8226 CELL BIOLOGY Endothelial cell transitions Are endothelial-to-mesenchymal transitions in various vascular pathologies a consequence, cause, or defense? By Elisabetta Dejana1,2,3 and Maria Grazia Lampugnani1,4 E ndothelial cells cover the internal sur- face of all types of vessels in the body and play a highly specialized role in protecting the vessel wall and the un- derlying tissues from noxious stimuli. These cells show organ-directed spe- cialization and adapt to the requirements of different organs. However, in pathological conditions—such as inflammation, fibrosis, and atherosclerosis—endothelial cells can change their morphological and functional characteristics and acquire properties of other cell lineages such as fibroblasts, myofi- broblasts, smooth muscle cells, and pericytes (which wrap around vessels) in a process called endothelial-to-mesenchymal transition (EndMT). This change of endothelial pheno- type may increase the vascular responses to thrombosis (blood clot), decrease permeabil- ity control, and increase fibrotic reactions. In addition, when endothelial cells undergo EndMT, they release abnormal amounts and types of growth factors and extracellular matrix proteins that constitute important mediators in a dysfunctional cross-talk with the surrounding cells. Given the relevance of EndMT in several pathologies, understand- ing the molecular basis of EndMT could be instrumental for the development of new therapeutic interventions. The switch to a mesenchymal phenotype is not a simple binary event. Instead, it oc- curs as a continuum with temporal changes in endothelial and mesenchymal marker expression. Cells that express at the same time both endothelial and mesenchymal markers are frequently observed in vivo in samples from both mice and humans, and detection of such coexpression has been crucial for the documentation of EndMT (1). It is therefore tempting to hypothesize that in a manner similar to the better char- acterized epithelial-to-mesenchymal transi- tion (EMT), endothelial cells undergo a set of multiple and dynamic transitional states characterized by the fine-tuning of different transcription factors, sequential expression of mesenchymal markers, and modification of cellular functions (2–5). EndMT can be reverted pharmacologically in cultured cells (2), although the persistence of such rever- sion upon drug withdrawal is not known. Currently, we do not know whether EndMT is a reversible phenomenon in vivo (to which extent it is reversible and in response to which stimuli) or whether some cells can reach and maintain an intermediate phenotype without progression to a clearly defined mesenchymal cell phenotype. These considerations are important because the progressive acquisition of mesenchymal features corresponds to different functional responses of the cell. These questions re- quire further experimental investigation. The process of EndMT has been docu- mented to occur in many pathological model systems and also in humans, although the actual contribution of this phenomenon to pathological dysfunctions remains a matter of debate (6–9). Skepticism about the biologi- cal relevance of EndMT appears mainly be- cause of technical limitations, including that individual mesenchymal cells derived from samples with evidence of EndMT are not al- ways easily distinguishable from fibroblasts of other origins, such as mesenchymal stem cells or stromal cells that are normally within tissues; it is also difficult to track EndMT in vivo. We envisage that EndMT is the result of a multistep phenomenon that follows spe- cific kinetics. Consistently, endothelial cells express different mesenchymal markers at different time points after EndMT-triggering events (2). Moreover, endothelial cells can- not be synchronized in vivo, and this leads to variability in the type of markers expressed. Additionally, the costaining of cells with spe- cific endothelial and mesenchymal markers can be difficult to interpret if the antibodies are not strictly specific and the signals suf- ficiently bright; cell-tracking experiments in mice are valuable, although the promoters that drive gene activation for those that en- code endothelial cell markers can be leaky and can also be expressed at low levels by nonendothelial cell types, thus making the interpretation of data difficult. These technical problems, however, can be solved to a large extent through the combina- tion of different approaches, such as in vivo cell-lineage tracing in mice and in vitro cell 1FIRC Institute of Molecular Oncology, University of Milan, Milan, Italy. 2Department of Oncology and Haemato-Oncology, University of Milan, Milan, Italy. 3Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden. 4Mario Negri Institute for Pharmacological Research Milan, Italy. Email: elisabetta.dejana@ifom.eu 746 16 NOVEMBER 2018 • VOL 362 ISSUE 6416 Published by AAAS on April 11, 2021 http://science.sciencemag.org/Downloaded from Lighting up the nighttime Kevin J. Gaston DOI: 10.1126/science.aau8226 (6416), 744-746.362Science ARTICLE TOOLS http://science.sciencemag.org/content/362/6416/744 REFERENCES http://science.sciencemag.org/content/362/6416/744#BIBL This article cites 13 articles, 3 of which you can access for free PERMISSIONS http://www.sciencemag.org/help/reprints-and-permissions Terms of ServiceUse of this article is subject to the is a registered trademark of AAAS.ScienceScience, 1200 New York Avenue NW, Washington, DC 20005. The title (print ISSN 0036-8075; online ISSN 1095-9203) is published by the American Association for the Advancement ofScience Science. No claim to original U.S. Government Works Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of on April 11, 2021 http://science.sciencemag.org/Downloaded from