by Krista Nutter, LEED AP, MS Arch
Of all the “green” initiatives, issues, or topics that I’ve done presentations on or spoken about, the one that receives more questions regarding its level of impact is light pollution. For the past several years, I have lectured on sustainable construction and techniques to make buildings more kind to the environment and ecosystems in which they reside. Along with the “big three” topics of energy efficiency, water efficiency, and indoor air quality, I also discuss things like material resources, waste management, and rainwater runoff mitigation. However one topic that always raises eyebrows is light pollution.
The Fernald Preserve in Harrison, Ohio is a LEED Platinum project that achieved the Low Light Pollution credit. Notice the inside lights don't project outside the envelope and that the sign lights don't project upward. Photo from Megen Construction Company's site. They were one of the contractors on the project.
KZF Architects' offices at 700 Broadway, Cincinnati, OH 45202 received the Light Pollution credit. Photo from their USGBC information page.
When I introduce the topic, I can almost see people thinking, “Light Pollution? How can light be pollution? These tree-huggers are just making stuff up now, right? We have so many other types of pollution to worry about, why on earth would we waste our time worrying about light pollution.” Interestingly, I always considered light pollution more of an annoyance or inconvenience than really an environmental issue. I knew that scientists who study the sky were concerned about light pollution, and that light pollution creates a certain difficulty for them in their observation, but I really didn’t understand how that impacted the environment in the big picture.
Then one summer, my family took a month-long trip to the western USA. We camped in 14 National Parks – which by the way are pretty big on protecting dark skies and educating people about light pollution. Most nights in National Park campgrounds, rangers host evening programs or presentations, and we happened to attend one on Light Pollution followed by an astronomy session with high powered telescopes in one of the darkest sky areas of the country (Bryce Canyon National Park, Utah). During the light pollution program, we learned most of what I already knew about down-facing light fixtures, colored light sources, and ways to control outdoor light pollution to mitigate the effects of your outdoor lighting on your neighbor’s property. However one part of the presentation focused on why addressing light pollution is important, and it was fascinating.
You see, addressing light pollution is more than just cutting down the light you send across your property line into your neighbor’s yard because “he likes it dark since he’s a star-gazer.” Addressing light pollution is actually quite critical in addressing environmental issues that impact local ecosystems, the food web, and other interrelated issues. Insects and animals have developed inherent behaviors over thousands of years, including migration, mating, feeding, and navigating their surroundings. These behaviors in some species require darkness without artificial illumination and can be negatively impacted by light pollution.
Here’s an example: In the light pollution presentation we saw at Bryce Canyon, we learned about a study scientists had done on the effect of light pollution on a certain frog population. In areas not affected by light pollution, the particular species of frogs being studied were observed to feed less during times of the full moon (which causes greater illumination in the frogs’ environment). However, when the moonlight was reduced through the natural moon phases or cloud-cover, frogs returned to feeding normally. The same species of frog was then observed in an area thought to be affected by light pollution. Scientists observed that not only did the frogs refrain from night feeding during the full moon, but they also refrained or significantly decreased their feeding in light polluted areas of their environment anytime the light pollution was present. This caused adult frogs from this area to be smaller, less-nourished, and also for mating activities to decrease thus causing overall population numbers to decline. This essentially affected every other species above them in the food web. In addition, populations of insects that the frogs feed on – including mosquitoes – significantly increased in the area, which, of course, could lead to a long list of other impactful issues.
To learn more about light pollution, you can visit the Dark Sky website at www.darksky.org. Here’s a one-minute video clip about what you can do to address light pollution in your community – you can start by turning off outdoor lights at night.
(This week's post comes from Krista Nutter, LEED AP, MS Arch is a college design educator and administrator at a CIDA-accredited program, a sustainable building consultant, and designer/owner of an award-winning, Energy-Star 5+, passive solar, solar electric, high-performance green home in Cincinnati, Ohio. Her home (shown) was on the USGBC Cincinnati Green Home tour in 2015. Learn more about at the house blog.)
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