Light Pollution Awareness – Drew Carhart (POY 07)

Drew Carhart has spent years raising light pollution awareness and encouraging fondness for nature near Chicago. Listen as he shares what he has learned.

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Monologue by Josh Morgan

This is The Plural of You, a podcast about people helping people. I’m Josh Morgan.

Drew Carhart is a board member and co-founder of the Illinois Coalition for Responsible Outdoor Lighting, a small group of activists that is raising light pollution awareness in the Chicago area and beyond. He volunteers his time to this and other activities around Chicago, and has done so for over four decades.

I talked with Drew recently via Skype. We spoke for over an hour about different topics, including his passion for environmental conservation and his role at the Field Museum of Natural History in Chicago, but I decided that this episode should focus on his light pollution work, and on how he shares his love of astronomy with members of his community. I believe that Drew sets a strong example for anyone who is concerned about the world’s environmental problems. I’ll play our conversation in a moment.

Whenever I think about our natural environment, I often find myself wishing that we as humans could get our act together, and that’s usually followed by a feeling of complete helpless. I think it’s because our society tends to group environmental problems using big labels—climate change, disasters, and mass extinction, to name a few—and that makes them seem like runaway forces that we have no control over.

I suspect many people struggle with this same discouragement, and that includes some environmentalists. For instance, I was speaking with a long-time environmental activist a few years ago. He told me that he and his colleagues had decided in the 1980s that the war for environmental change was lost, and that all they could do was prepare people for the worst.

That approach—you know, the one that says we’re all doomed and can only make the best of our terrible fate—is certainly one way to look at the situation. Another is to deny that these problems exist at all, or to suggest that humans are not involved in them, but I’ll leave those alone. I’d rather talk about the approach that Drew embodies. It’s based on the notion that we can still reverse, or at least manage, how negligent we’ve been with our natural resources, and that there is still time to turn things around.

One hindrance between us and lasting change is that many environmental problems seem unsolvable from an all-or-nothing perspective. We often slip into exaggerated expectations when we realize that a problem will require more than a quick, one-shot fix. That can affect our motivation to do anything, and that makes sense to an extent: I mean, if a problem seems too enormous, then why bother confronting it?

Say you have a big problem like light pollution, which has emerged only within the last few decades. The problem can be reduced to each individual light bulb in the world, if you think about it. Turn off all of the ones that are outdoors at night, and the problem would cease to exist. Because no one is capable of doing that alone, light pollution can seem a lost cause, even though each of us can take responsibility for the light bulbs in our own neighborhoods. Correcting light pollution near our homes won’t solve the problems of light pollution everywhere, but it will make our own communities a little nicer to live in. Like you’ll hear Drew say, that’s worth the effort.

Drew talks about the loss of the night due to light pollution with an almost spiritual reverence, like we’re losing a part of ourselves, and he wants to help restore that experience for future generations. I wasn’t conscious of it before I contacted him, but it’s interesting to think about how daylight and darkness influence our beliefs and our behaviors that way. Lighting up the night has changed a lot of things for us, and not just us, but among other forms of life. I read in one study that songbirds change their singing behaviors in the presence of light pollution. The authors of another study found that light pollution can transform how local ecosystems are organized, meaning predators and scavengers can thrive despite the rest of the food chain. That said, it’s not farfetched to assume that outdoor lighting has subtle effects on us, too.

Big problems like these are the sum of smaller problems that have accumulated over time. Untangling them takes diligence. They can be solved, but only together with other people. That’s what Drew and his colleagues have been proving for many years. I hope you’ll consider the implications of what he has to say, namely that no problem is so big that we have to give up on it. Here’s Drew Carhart, board member and co-founder at the Illinois Coalition for Responsible Outdoor Lighting.

Interview with Drew Carhart

JM: Hi, Drew. Did you have a good week?

DC: A busy week. I have kind of a confused schedule. I share my time between lots of different projects, so I’m constantly changing the part of my brain that’s functioning.

JM: What projects are you involved in?

DC: I could preface it all by saying that I’m in the phase of my life where I donate my time to various things. I spend part of my time at the Field Museum, helping there. I spent part of my time doing my light pollution work. I also still donate quite a bit of time to my astronomy club. It’s busy. [laughs]

JM: Yeah, it sounds like it.

What made you interested in light pollution?

DC: I’ve been interested in everything to do with nature for my entire life. My earliest memories are not of playing with toys as much as being outside, watching seeds sprout and birds fly, things like that. I got interested in the universe around us probably in my early teens, and really started to enjoy astronomical work and looking at the planets and the stars.

Over that time, I watched the sky over suburban Chicagoland, where I grew up and still live, pretty much disappear from view—the nighttime sky, that is. Then I started to dig a little bit more deeply and realized how much the issue affected the other parts of nature that I’m interested in, and also how very little studied that has been up to this point. It actually became a more important aspect to myself when I started realizing what changing night into day does out in nature.

JM: I’m curious hearing you say that. Are you a trained as an astronomer?

DC: Oh, no. It’s just an avocation for me.

JM: Okay.

DC: …and it’s a tremendously fun thing to share with people, too. My astronomy club, which I actually helped found 42 years ago now—

JM: Oh, wow.

DC: We do a lot of outreach. It’s a lot of fun to give people views through telescopes that have never seen the craters on the Moon or have never seen the rings of Saturn and things like that before. It’s hard to imagine how many amazed exclamations I’ve heard over the years. [laughs]

JM: [laughs]

DC: All the wows and oh-my-goshes and “I don’t believe this!” So it’s a lot of fun doing that. Of course, I find it fun on the other end, too, when I can show people something through a microscope: the little things living in water, or what a fly’s wing looks like close-up. There’s a lot of amazing stuff in nature.

JM: For sure.

I’d like to talk more about your light pollution work. Would you mind describing the history of outdoor lighting, just to set some context?

DC: Sure. To really ground things, you have to realize that human beings are diurnal creatures. We are kind of built to live in the daytime. We are pretty dependent on our eyesight, which is not particularly sensitive at night. You have animals like owls, and we’re familiar with cats and things that are nocturnal. Actually, a large percentage of animals—I think it’s about sixty percent of mammals—are nocturnal. They probably have better eyesight at night than we do. We’re very limited, and that makes the nighttime scary for us.

We’ve been adding light to the night probably since we’ve been humans, [like] having a campfire, which evolved into the oil lamp and into the candle. Light used to be very expensive back in the days of the oil lamp or the candle. For the most part, night time was for sleeping. The exception would be when the moon was out in full. That’s why we have—our full moons are named things like the hunter’s moon and the harvest moon in the fall, because when the moon was full, you could still work at night. You could go out hunting or you could harvest during the night.

JM: Oh, interesting.

DC: As the technology developed, our lights got relatively cheaper and plentiful, so we started using them more at night. Of course, when electricity came around, it made the big difference. Still, even with the early electric lighting, the levels of lighting we were trying to achieve in our cities were basically around at a full moon. It wasn’t so that you could read a newspaper or do delicate work out on the street. It was so you could tell where the street was. That seemed quite sufficient to people back then.

As the technology developed, we didn’t say “Let’s use less and less resources and less and less energy, and keep this low level of lighting.” We kept on adding more lighting. Anyone who dates back to the 1960s will remember the kind of bluish glow over cities, then the switch to the orange-yellow color of the high-pressure sodium bulbs, which light up a lot of our skies now.

Those were all steps that increased the efficiency of creating light, and what we did with everyone of those steps was not use less energy—we used more light. What that ended up with was, in the last quarter of the twentieth century, a huge explosion in the amount of light we put out into the environment. We’re talking ten, twenty, thirty times as much light oftentimes coming from a given area. That’s where a rapid change in the loss of stars in the sky came in, and probably these environmental effects, too.

JM: What are the major problems that concern you with outdoor lighting?

DC: There’s kind of a handful.

What should be a fairly obvious thing is the amount of energy we’re using and the amount of energy we’re wasting. If you have a light that’s twice as bright as you need, that means you’re wasting half of the energy. If you have a light that’s on for the full night when it only needs to be on for half the night, you’re wasting half of the energy. If you’re lighting up the sky like we do—if you live in a town or a city, and you go out at night and you see the light up on the clouds, that’s light that you’re consuming electricity to make. Instead of shining it where you want it, you’re lighting up the clouds with it.

JM: I never thought about that.

DC: If your town or your city said, “Oh, we’re going to have a new program to light up the clouds over the city, or the bottoms of airplanes flying overhead,” you’d say, “Well, this is stupid,” but we do that. That’s because the lighting we put in is really poorly designed. Anyway, the energy is a huge factor.

The environmental impact is something that we’re only just starting to appreciate because it’s been looked into so little. There are thousands of other organisms that we share our environment with. Even if you live in a city, there’s other living things there. We have studied individually very few species to find what happens if you go from having light in the day [and] just starlight or moonlight at night to having artificial lights turned on all night. In the cases where we have conducted studies, we’ve found dramatic effects, and it kind of only makes sense. It’s supposed to be dark at night. All of our co-inhabitants of the planet are evolved under that setup.

JM: What about social effects on humans?

DC: That’s another thing. We’re putting in lighting to make the night viable for us, so we can do things. It’s a huge factor in society and, for the most part, it’s a very positive thing. On the other hand, you can argue that the 24-hour day isn’t realistic for humans. Certainly, if you live in the temperate United States, the winter nights start pretty early. If we all had to go home and be in bed at 5:00 [PM], that would certainly be a change of pace. [laughs]

On the other hand, bad lighting is doing things that are actually negatives. If you go down a street and a light is glaring in your face, that can be a very negative effect. There’s oftentimes been a kind of kneejerk assumption that all light is good light. The funny thing is, in most of our common, everyday experience, if you’re out at night, you can look and easily see examples of bad lighting. You can say, “I had to squint,” “I couldn’t see,” “There were dark shadows because of this bright light shining in my face.”

Then, an important thing is talking about the health issue, because we are animals, too. It turns out that humans are extremely photosensitive. This is really kind of a new concept. If you look at a physiology textbook from the 1980s or 1990s, if there’s any mention at all about how photosensitive humans are, it’s usually very downplayed or even…kind of—

JM: Minimized.

DC: Right, exactly. Just in the past fifteen years, there have been tremendous discoveries about how photosensitive we are. We like to think we’re in charge of our bodies and in charge of what we do, but the fact that we need light in the daytime and dark at night to have our body function correctly is very underappreciated. I think it’s something we’re going to hear a lot more about in the near future.

Probably as far as most of us go, a lot of our nighttime light exposure happens in our own indoor spaces that we somewhat control. On the other hand, that light shining in your window, the street light glaring in or [light] from the neighbor’s yard or from the business next door or whatever, might be having notable effects on your health.

The last of the handful of items is losing the stars from the sky. Most of the people around the world now, certainly in the United States, the vast majority of people live in urban areas. Our children are growing up not knowing what stars look like.

JM: Oh, that’s sad.

DC: Well, it may seem like a trivial thing, but it’s going to have societal effects in the long run, too. We have fewer people feeling that connection, that the Earth isn’t the center and the only thing out there, that we’re part of a huge universe. We’re taking that away, again, not by using light but by carelessly using light.

JM: Given all of these problems, in your estimation, why do you think light pollution is so difficult to talk about in our society?

DC: It’s just a matter of awareness. It’s partially because of the very deep-seated fear of the darkness we just have as a species, which is a shame, too. I love the night. [laughs] Being out in a dark place and seeing the stars is great, but just using your other senses and hearing the night around you, and smelling the night around you, is amazing.

JM: Yeah, it’s comforting in a way.

DC: Yeah! It shouldn’t be a scary thing, and it’s unfortunate when we promote it, especially to children, as being afraid of the dark when they shouldn’t be. They should learn to enjoy it. Anyway, it’s an ingrained thing as human beings, that we don’t like the dark. You can see that sociologically in our references to the dark. Evil is darkness, darkness falls, darkness is bad. [laughs] It’s all the negatives, whereas good is bright and light. That’s a hard hurdle to overcome.

The other issues are partially how this crept up on us. I’ll talk to people in their forties, fifties, sixties, who watched a lot of this change in the amount of light we use outdoors, and they don’t realize it. I’ll show graphics to illustrate the changes over the last half of the twentieth century, and they’re like, “Gee, I lived through that, and I didn’t realize how much brighter it was in, say, 1990 than it was in 1960 outside.”

JM: That’s a good point.

DC: So it crept up on people.

Then you get to the issue of, in society, people still figure—no matter how many times we’re shown the opposite—people still figure that whoever takes care of this knows what they’re doing. [laughs]

I oftentimes compare the light in the environment to things like light pollution. When I was a kid, I lived near a moderate sized river, and there was sewage floating in the river. [laughs] You could see the sludge from the towns up the river floating down the river. It was kind of what you did. You dumped your sewage into the river. Nowadays, we realized how bad that was, and we’re not doing that. [laughs] Back then, it was what you did.

We assume that somebody is taking care of the street lights when they’re being put in: the lights around businesses, things like that.

JM: They wouldn’t be installed if someone hadn’t decided they should be.

DC: Yeah. “It’s not my problem,” “There must be experts doing it.”

I was kind of surprised—I studied some engineering things in the past. I really was surprised in getting involved in the outdoor lighting work, and looking at the engineering and how it’s done, of how primitive an awful lot of it is. [laughs] Here’s an example.

I think a lot of people are aware of energy efficiency standards that apply to a lot of things around us, not just our cars but your furnace, your refrigerator, things like that. In the U.S., they have to meet certain efficiency standards. None of the street lights around you face any efficiency standards. They still don’t in the United States. That doesn’t make them a lot of sense when you think about it, when you think about the millions of these things that are out there and are running every second of every night, but it’s just flown under the radar. That’s one of the things I kind of discovered early on working with this.

What needs to be done first is just a raising of awareness. That’s an issue, because society isn’t going to change anything that it doesn’t realize needs to be changed. That’s become more my focus and my group’s focus, to just get the word out there. Again, a lot of it is not too hard to explain. Invite anyone to go out and drive around at night a while, and ask “Is this light needed?” “Is it shining its light where the activity is, where it’s supposed to be lighting up an area, or is it shining all across the universe instead?”

Some of it’s quite obvious, but again, it’s something that we haven’t tackled much as a society. That’s why I chose it as my focus issue.

JM: It’s a bit uncharted.

DC: Yeah. It’s waiting for people to pick it up and carry the banner, and make it more of a public issue.

JM: Where has your group been successful in the past?

DC: What’s been most successful for us is to go where we’re asked to go. When a community comes to us and says, “We’re looking at our lighting situation. We would like to do this job right.” We’ve helped in some cases where they actually wanted to create a local ordinance for outdoor lighting. Those have been very constructive arrangements. They’ve happened kind of randomly.

Several years ago now, we were contacted by a county here in northern Illinois. They were looking at digital billboards coming in, and they were interested in it from the light point of view because they realized these things put out 30-40,000 watts of light into the night. I actually had to do some studying myself [on] how to compare one of these digital billboards to a standard, painted billboard with light shining on it.

We actually helped them draw up one of the first ordinances in the country for regulating digital billboards. There wasn’t a lot of existing work on that because they’re a new technology. That wasn’t something we ever set out to do as a group, but it ended up being a very interesting thing to study. Actually, our work is still quoted on that.

JM: That’s great.

DC: I see it in the practice around here, of how bright the billboards are. When I see a billboard that’s turned down to a nice level at night, I think, ‘Wow, that’s nice. I think we had something to do with that.’ [laughs] There’s things like that.

I’ve never been much of a political activist. I’m not a stand-up-and-scream-at-the-meeting person. That’s not been my nature. I’ve had a lot of heated discussions with people. Back in that instance, we had people from the two biggest outdoor advertising companies in the country come and meet with us. That was kind of fun that they thought, ‘Hey, look. This little group is worth picking on.’ They actually changed their attitude on some things, which was nice.

JM: So you helped establish the precedent, in some ways.

DC: In some ways, yeah. It’s still an issue that’s hotly argued around the place. As a small, activist group, a conservation group here, to have some effect in that was good. Again, it wasn’t us just writing letters to the billboard companies or to cities that had never heard of us. It was that we were willing to step in and help, and provide some expertise.

JM: I know you’re also active in encouraging astronomy among young people and amateurs. How are you involved in that?

DC: My area astronomy club here, we actually founded when I was in high school. We were an odd bunch of kids who wanted to do way more than local high school would let us do. [laughs] We formed an independent group, which is still here now.

JM: That’s impressive.

DC: For some reason, I stuck with it for all these years. A little bit had to do with us starting with this group of kids. We started with this very young, active attitude. We ended up building a club that looked a little bit more like that. We had a diverse membership, and we did a lot of stuff. One of our focuses all along was the public outreach because we saw the importance of it, but also because it’s an incredibly pleasurable thing to do. I still delight in it.

It’s interesting—I’ve heard from other amateurs. They’re thinking when we do a youth group, they’re thinking, “Gee, maybe one of these kids will go on to be an astronomer someday.” I don’t set that as my goal. I think more like, “Gee, maybe when this kid is seventeen, someone will say something about astronomy, and instead of saying, ‘Oh, yuck, science,’ they’ll say, ‘Oh, I did that once. That was cool.’” That’s all I’m looking for. I’m looking for that little bit of attitude change, that someone now appreciates how neat it is to see the craters on the Moon, or to have somebody explain to them that this nebula they’re looking at, that the light came from it 2,000 years ago and that it’s just shining in their eye now. Little things like that.

JM: If I wanted to reduce light pollution in my community, where would you recommend I start?

DC: The good starting place would be to familiarize yourself with the issues a little bit. We try on our organization’s website to provide a good grounding in the ideas, what we’re talking about with good lighting versus bad lighting, good effects of lighting, bad environmental effects of lighting, to learn to recognize the differences, and to look around your community and think about what actually applies in your community.

If it’s a smaller town, it may be an issue of people’s lighting practices. Do the businesses leave their lights on all night in the parking lot when there’s nobody there? They can put in a timer that would turn them off when half the night is over and save a lot of energy. It might be a matter of raising community awareness more about these practices.

A large issue today is that municipalities are switching out to new street lights which they are told they will save money on. They’re not thinking while they’re doing that if they’re good street lights or bad street lights. Are they also thinking about whether, “Gee, do these shine into people’s house windows? Do they do the job that’s needed? Do we need this much light? Do we need more light?” Taking advantage of that situation and acting now to influence what street lights are chosen is a big deal, because they won’t get changed out for another twenty, thirty, forty years.

It depends on your community. Like I say, getting informed a little bit about all of these issues is a good place to start. Seeing if you can get other people on board with you is a big thing. Having even a small group of people—even if there’s three people in a community who are wanting to push this sort of issue a little bit, it’s a lot better than working by yourself. It can be disheartening working by yourself after a while, when you’re the lone voice out there that’s trying to get a point across.

You have to remain positive about things, and realistic about things. It’s hard for amateur astronomers. They would like to see all of the stars come back at once, and that’s not going to happen. We’re not going to revert to the sky of 1960 or 1970 in a week here. It’ll happen eventually, I think. My attitude has always been that I can’t guarantee that a positive thing’s going to happen from this work that I’m doing, but I can guarantee that positive things aren’t going to happen if I don’t do the work. [laughs]

JM: Oh. I like that, yeah.

What about porch lights at people’s residences? What are your thoughts on those?

DC: We have a paper on our website where I address that. To me, the obvious thing is that people are looking for security. They want to feel safe. [Are] our porch lights contributing to the majority of the skyglow over cities? No, but they’re still consuming energy, and they’re still dumping light into the night.

In reality, there aren’t any good studies that show that porch lights are going to keep your house from being burglarized. Two-thirds of residential burglaries happen during the daytime. That’s the FBI’s figures. That kind of indicates logically [that] darkness isn’t the threat there. The logic is that more burglaries happen during the daytime because burglars know you’re off at work, and it’s safer to break into your house when there’s nobody at home rather than at night when you are home.

JM: Right, that makes sense.

DC: But the porch light doesn’t make it any safer. You can even argue that the burglar needs the light, too, to break in. They don’t see any better in the dark than anybody else.

The flipside is, if you want to look at studies and what’s actually effective, having the porch light on a motion sensor does seem in some studies to have a positive effect. Instead of the light just being on all night, it actually flips on when somebody comes by. That’s more likely to attract the neighbors’ attention. If your light is on all the time, your neighbors don’t sit and stare at your front door all night long to make sure nobody is coming by. If the light flips on and catches somebody’s attention, and also the person going by doesn’t know whether you turned it on inside and saw them, that seems to be a discouraging thing. If it’s on all the time, there’s very little effect.

From my point of view, it’s not just look at the energy waste or the environmental act of it, but what’s the reason for doing it in the first place.

JM: Looking forward, what do you find encouraging about the issues with light pollution?

DC: Well, there are people around the world who are actively doing research, and that’s a huge thing. Again, especially when you’re talking about the environmental issues and the health issues, they are so little explored. To me, it’s rather obvious that, [if] we turn lights on outside, it’s going to change things ecologically. I don’t see how you could develop a model of nature where that wouldn’t happen.

What we need is more data. We need more actual research that says this is the kind of thing that’s happening. That kind of work is being done. There are simple things, like I could say go out and look at a street light this June on your street and see all of the insects flying around it. They’re not supposed to be there. You’ve got a thing right there in front of you showing that light is affecting the environment, but we need more data on that.

Part of that is that we need a much better understanding of the different colors of light, which is a non-obvious issue to us as humans. All we care about is whether we can see down the street or see a person coming towards us. The quality of light, the spectral quality has huge effects.

JM: Yeah, because different organisms see different spectrums, right?

DC: Very much so, yeah. When we’re talking about this changing out our street lights from the yellowy, high-pressure sodium lights, to now the LEDs coming in, we’re not just talking about the same amount of light, like switching a bulb that’s no different. We’re talking about changing the universe out there, as far as the light at night. Again, we need more research on that to guide how that’s done better. The encouraging thing—you asked for the encouraging thing—is that there are people doing that research.

The health issue things—every time I see an article in the popular media that touches on the subject of why you shouldn’t be staring into your tablet at midnight and having it shine in your face, [that is] just broadening the awareness that light is not a benign thing. It can be a tremendously positive, wonderful thing, but it’s also a potent thing.

JM: You mentioned your website earlier. Where can we follow you and your groups online?

DC: For our lighting work, we’re We have a lot of information.

JM: And I really enjoyed it when I read through it, by the way. I think you did a good job.

DC: Well, we’re always trying to think of resources to add there. Those are usually based on inquiries we get, like your question about porch lights. We have a page there where we address that.

The astronomy club, for anyone in Chicagoland—we’re based in the suburb of Naperville. If you Google the words naperville and astronomy, you will come to the top of that list.

JM: What if someone wanted to contact you? What would be the best way to do that?

DC: Through our website. We have an email contact set up there. We get a lot of requests from all around the world. If people are in Illinois, we’ll come and give programs. We’ll come and talk to the city council or to the conservation group or whatever. I probably do six outreach events a year myself, on average. If you go to telephone requests and things like that: once or twice a month.

JM: Oh, wow. Okay.

DC: I never would have been able to predict the assortment of people and places and organizations that we’ve been contacted by. It’s great. Again, it’s a wide-reaching thing.

JM: Alright. Is there anything you’d like to add?

DC: Well, I can talk light pollution forever.

JM: Well, I really admire the work you’re doing, so thank you so much.

DC: Oh, thank you. Thanks for your interest!

JM: Okay, sounds great, Drew. Have a good day.

DC: You, too.

Conclusion by Josh Morgan

This episode of The Plural of You was produced by me, Josh Morgan, in blooming Edinboro, Pennsylvania. Mike Martinez created the music.

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In closing, here’s a homework assignment.

The National Sleep Foundation says that about four in ten adults in the U.S. don’t get the recommended seven to nine hours of sleep they need per night. Light is one of many factors involved in sleep quality, so if sleep is a problem for you, try dimming your lights, covering your windows, and turning off your electronic devices about an hour before bedtime. Make sure your own outdoor lights aren’t bothering anyone, and talk to the owners of lights that could be bothering you. A good night’s rest will help you feel better, think more positively, be safer and more productive, and it will show among the people you care about in the long run.

That’s all for now. Thanks for listening.