Bring back the dark: How our overuse of artificial light is changing nighttime for the worse

Author Paul Bogard on the war we should be waging against light pollution

Published August 9, 2014 8:00PM (EDT)

    (<a href=''>chungking</a> via <a href=''>Shutterstock</a>)
(chungking via Shutterstock)

You don't know night. Not real night, the way it was experienced pre-electricity; what we lost when we developed the ability to light up the night sky.

That sounds obvious to someone living near Times Square or in Vegas, but those are only extremes in a phenomenon that touches nearly all of us: Two-thirds of the world's population, and 99 percent of people living in the continental U.S. and Western Europe, no longer experience what we might call true night -- one free from the glow of artificial lights.

It seems natural to mourn that loss, albeit without getting too riled up about it. After all, few things signify civilization's progress more effectively than satellite images of the continents lit up at night. But according to author Paul Bogard, light pollution is pollution, misused and overused in ways we don't typically realize. Artificial lighting, he argues, is one of those great, beneficial innovations that, somewhere along the way, became too much of a good thing.

"The light we see in photos from space, from an airplane window, from our 14th-floor hotel room, is light allowed to shine into the sky, into our eyes, illuminating little of what it was meant to, and costing us dearly," Bogard writes. "In ways we have long understood, in others we are just beginning to understand, night's natural darkness has always been invaluable for our health and the health of the natural world, and every living creature suffers from its loss."

"The End of Night" is Bogard's exploration of that loss, ranging from the practical -- all that wasted energy -- to the philosophical -- what does it mean that we no longer experience true darkness? And on the practical end, Bogard tells Salon, it's clear that there's a lot we could be doing better. The good news is that of all the world's problems that need fixing, better lighting is a relatively easy one to tackle. The bad news is that, well, we're still doing it wrong, in ways that will be hard to correct later on. We discuss what needs to be done -- and why we need to start now. Our conversation, edited for length and clarity, is below.

Of all the pollutions -- air, water, etc. -- light pollution is probably the one that we hear about least. But in the book you make it clear that artificial lighting is a pollutant, and there are some clear ways of defining it. Could you discuss how that works?

I think the definition of light pollution is the overuse and misuse of artificial light at night. That’s how I would define it. I think that speaks to the problem. We’re just using way too much of it; way more than we need and in ways that aren’t very helpful to us. The evidence of that is things like skyglow, which is the glow you see over cities, especially on cloudy nights, which will amplify the lights. Or glare, lights that are shining directly into our eyes, oftentimes into our bedrooms. This is a problem for drivers at night. There’s a lot of glare. And then there’s something called light trespass, which is light that shines from one property onto another. So you’re lighting your yard, but you’re also lighting up your neighbor’s yard as well. So those are the primary ways we see evidence of light pollution.

Are there measurable impacts it’s having? What are the ways we can see it having an effect on, for example, wildlife?

Well it’s a little bit of a challenge because there hasn’t been a whole lot of research on it. It’s a problem that’s relatively new and so it’s just in the last five or maybe 10 years that they’ve begun to study the impacts on a lot of wildlife. What I say is that life on Earth evolved with bright days and dark nights. All life on Earth evolved with that. So to think we can flood a habitat with this kind of light and it not have an impact doesn’t make sense. Sixty percent of invertebrates -- insects, mostly -- and 30 percent of vertebrates are purely nocturnal. They need darkness to function and live. And some of the other animals are crepuscular -- that is, they’re active at dusk and dawn. They also rely on darkness. One of the reasons I love night and why it’s really important is I feel like it’s when the wild world really comes alive. It holds its breath during the day and then it releases it at night. It feels like “good, the people have gone inside, now we can come back out at night.”

You also write about the human health impact. Is there legitimacy, for example, to the studies that say artificial lighting could be a factor in causing cancer?

Oh yeah, I definitely think there’s legitimacy. The World Health Organization now, for example, considers working the night shift a probable carcinogen. It’s ranked at the same level as breathing diesel fumes. It’s really hard on us. The three main ways people are finding out it’s having an impact is that it’s disrupting sleep and contributing to sleep disorders; it’s interfering with our circadian rhythms; and it’s impeding producing the hormone melatonin, and the lack of melatonin in our blood has led to an increased risk for breast and prostate cancer, for example. Again, I think it’s very serious. The people I talked to said you can’t say light at night gives you cancer because you don’t know that. But it sure seems to screw up our bodies.

There’s a lot out there about how using iPads, and general "screen time" before you go to sleep, could be messing things up. But just ambient light, and artificial light coming from other places, can also be a factor?

That’s what they’re trying to figure out right now: what level of light makes these impacts. How bright does it need to be in your bedroom? Is light coming in from the street enough? Or do you need to have the light turned on? People working the night shift are under lights all the time. So that’s different than most people at home. As you said, they've found that if you’re staring at a screen before you go to bed, production of melatonin in your body won’t start for at least an hour after you turn off the lights, so you’re missing that right off the bat.

The thing about the light we’re seeing on our screens is that it’s a blue light, and that is particularly hard on our bodies because that’s the wavelength of light our bodies have evolved to think is “wake up” -- it’s the same light we see in the blue sky, for example -- so that’s problematic. And a lot of the new street lights, the LED lights, are what they call blue-rich white light; it’s heavy in this blue wavelength. So much of this problem is, “We’re going to have lights, we’re going to have street lights, but what kind of light are we going to have?”  We need to try to get people to not use lights that are heavy in the blue wavelengths.

So is that something that just wasn’t taken into consideration when they were putting up these street lights?

Exactly. It’s happening as we speak. And LED technology is evolving very quickly. It’s the lights a number of cities are already using. They’ve already put these blue-rich white lights up; and LEDs, the thing about them is they’re designed to last for 20 years.

Oh boy.

Yeah. There are people telling me we’re installing obsolete technology.

Are there better technologies out there? Better light bulbs? Better things that can be done with street lights to reduce their impact?

It’s changing very rapidly. But in general, I would say that yes, there are options. Essentially, what a lot of cities are doing is choosing the cheapest option, which is this blue light rather than a warmer light, more of an orange or reddish light. The other big thing is that you get an immediate 30 percent reduction in energy cost with LEDs; they’re that much more efficient. But they could be even more efficient if you used what's called adaptive controls. One of the good things about LEDs is that they’re programmable. Paris is trying to do this right now, where they’re going to be able to control the lights. In some parts of the city that are not very busy, they can turn the lights down in the middle of the night. In some other parts, they can turn the lights up. But you have to install this when you put the lights in.If you don’t do that when you install the light, it’s sort of prohibitively expensive to go back and put them in after the fact. Basically, most cities are not doing that because they’re saying “It’s too expensive to do that.” New York City right now is retrofitting 250,000 street lights and they’re not putting in adaptive controls. So basically they’re installing obsolete technology. So that’s what’s really frustrating for me and the people I talk to in the book. It’s like, we could do so much better. There are better lights. We could put controls on them, and people are choosing to not do that.

And it won’t end up saving money, because you’re using more energy in places that don’t need it.

Exactly. It’s the same old thing we’ve heard in other issues. It costs more at the start but in the long run it would save money and energy, but people are afraid to do that.

Can you think of examples of other cities or places that are doing lighting right? Like the anti-Vegas?

Well the two cities I point to most often are Flagstaff and Tucson in Arizona. They both have very strict (in a good sense) lighting ordinances, mainly because they have astronomical observatories near them -- Flagstaff has Lowell Observatory basically right in the city. They’re not perfect; nothing is perfect. But they show us how we can do things. A good example of the way we light that’s kind of dumb is that parking lots and gas stations are lit about 10 times as bright as they were 20 years ago. And a lot of parking lots are lit up all night long whether there’s anybody there or not. And if you go to Flagstaff, for example, you’ll see the gas stations are lit at a much lower level, and everything is fine. And the parking lot is lit at a lower level and everything is fine. People think if we have less light we’ll be overrun with crime, and it just isn’t the case. So I think even though those cities aren’t perfect, they’re really good models for what other cities could do.

Do you think there’s a case for having ordinances like this be more widespread or for regulating light like we do other pollutants?

Yeah, I think so. Absolutely.  There’s something called “second-hand light,” basically. It’s the same thing like with second-hand smoke. One of the guys I talked to from Harvard, who works on sleep, feels like we are with our understanding of light where we were in the ’50s with our understanding of smoke. We’re just beginning to understand that it’s having an impact on us and that it’s not good. And it gets back to this idea of light trespass and light pollution, in that it’s one thing if you want to light up your house, but you’re also lighting up your neighborhood. We allow things like businesses to be blasting light in all directions and it impacts us. It impacts other people. So I think absolutely in the same way that we would regulate noise pollution is a good analogy. You’re not allowed to have a blasting stereo at midnight or something like that. They’ll call the cops and get people to turn it down. But when it comes to light, you are allowed to just blast it whenever you want to.

I think there’s a Seinfeld episode that deals with those business signs.

There probably is. And that’s a really good example of signs now: digital billboards are spreading everywhere. There are at least 5,000 digital billboards in the country right now and 400 more go up every six months. So it’s one of those things where it’s happening now, it’s spreading now. So now is a really good time for communities to be thinking, do we want big bright billboards in our community or not?

I was also struck by the connection you drew between artificial lighting and injustice, with the health problems for shift workers but also prisoners and people in public housing projects. That seems like something we don’t pay attention to. 

I think it’s really true. By and large, the people who work the night shift are not privileged people. They are disadvantaged people. They are people of color. They are poor folks; it’s the best option for them to be working all night. It’s just hard being up all night long anyway. And I’m speaking in general now, but I know there are a lot of poor neighborhoods that are very brightly lit. I think it is an environmental justice issue for sure.

Does anywhere exist where people can still experience "real" darkness. Or have we completely moved away from that?

I think people do. You can go places like out into the ocean or the Australian Outback or the middle of some continents. Natural, real darkness certainly still exists, and in places like Africa there are movements to get light out to people who don’t have any light at all. I don’t think anyone is against that. That’s not what we’re talking about. What we’re talking about is where most of us live: in North America and Western Europe we’ve lost natural darkness and we have way too much light and that’s the big problem. And I guess in terms of the book, people say “Did you go to Antarctica? Did you go to the middle of the ocean?” And it’s like, I’d be happy to do that but that’s not what the book is about. The book is about the night that most of us no longer experience.

So in the year since the book first came out, have you seen the conversation advance or evolve at all? Because it’s disheartening to hear New York is still installing the wrong kind of street light. 

Yes and no. I think I’ve certainly been trying to do my part with interviews and with presentations, and everywhere I go and whenever I talk about it, I feel people are receptive to it. I feel there’s a real sense of people saying “I’ve never really thought about it.” And when you think about it you think, “This is stupid. Why are we doing it this way?” And that’s certainly my message. Nobody is saying let’s not have light -- we’re saying the way we’re using light now isn’t smart. So I think the conversation has been turning, but it is one of those sort of turning-the-aircraft-carrier metaphors. We’re so used to doing it the way we’ve been doing it for so long that making changes is going to take some time. I will say the advancing of LED technology offers an opportunity to advance the conversation, to get people thinking about how are we lighting. Because really we’re moving from electric lighting to electronic lighting and it really offers us a chance to control the light in ways we haven’t been able to in the past.

By Lindsay Abrams

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