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Making War On Light Pollution
Hugh Pickens writes "Almost thirty years ago I worked in the Middle East helping install a nationwide communications system and had the opportunity to be part of a team doing microwave link tests across Saudi Arabia's Empty Quarter. Something I've never forgotten were the astonishing nights I spent in the desert hundreds of miles from the nearest city where the absence of light made looking at the sky on a moonless night feel like you were floating in the middle of the galaxy. In Galileo's time, nighttime skies all over the world would have merited the darkest Bortle ranking, Class 1. Today, the sky above New York City is Class 9 and American suburban skies are typically Class 5, 6, or 7. The very darkest places in the continental United States today are almost never darker than Class 2, and are increasingly threatened. Read a story from the New Yorker on what we have lost to light pollution and how some cities are adopting outdoor lighting standards to save the darkness."
Someone's firing too much magic missile.
I live in Salt Lake City, and the light pollution here is just like any other city. My favorite place is to visit Lake Powell, near the Arizona border where there are no city lights for at least 50-100 miles.
I always thought it would be nice if we had one day a year where people made a conscious effort to turn off all their lights, like "Star's Day" or some other stupid name so people could have one night a year to keep lights off, but that would inevitably just lead to an increase in crime for that night, so... darn.
We'll just have to enjoy it when I'm camping.
"Thank you for using Stop-n-Drop, America's favorite suicide booth since 2008"
A couple that was married for 20 years always made love with the lights off.
Well, after 20 years, the wife felt this was ridiculous. She figured she would break him out of this crazy habit.
So one night, while they were in the middle of a wild, screaming, romantic session, she turned the lights on.
She looked down... and saw that her husband was holding a battery-operated pleasure device -- a vibrator -- softer and larger than a real penis.
She went completely ballistic. "You impotent bastard," she screamed at him, "how could you be lying to me all of these years? You better explain yourself!"
The husband looks her straight in the eyes and says calmly:
"I'll explain the toy... if you explain the kids."
Moral of the story? everyone is happy when you turn the lights off at night.
The most impressive sky I have ever seen was right after a typhoon on the island of Guam.
I snuck out of my house when I was 16 and the island was still under a typhoon warning and nobody was outside.
The entire island and the neighboring island of Truk were both without power entirely and there was not a single cloud in the sky.
It truly was a spectacular sight and I do feel sad when I look up into the night here in the states.
You can't imagine what it's like until you've seen it for yourself. Really
Rats would be more funny if they could fart.
The average supermarket parking lot is much brighter at midnight than necessary. You also don't need the entire parking lot lit all night, when on most nights, the first two rows of lights would suffice for the night-time customers. After parking lot lights, the biggest offenders are billboards and other illuminated advertising signs. These can be turned off without compromising public safety, and with minimal harm to the efficacy of the advertising.
If you would RTFA instead of rushing for first post you'd see that it mentions that, when properly done, reducing the excessive and inappropriately strong lighting that covers most cities would actually aid nighttime vision by eliminating the glare.
it is sad truth that most people prefer feeling safe to actually being safe.
"It's such a fine line between stupid and clever" -- David St. Hubbins, Spinal Tap
The darkest - best sky I have ever seen - in the middle of the Atlantic Ocean its pretty dark !
I remember how easy it was to see all the space junk flying overhead - and some nebula's and galaxy's
could be discerned with the un-aided eye.. Too cool. Light pollution sucks...
All we need to do is install more power stations with Windows and the viruses will do the rest:
http://www.cnn.com/2003/US/08/14/power.outage/
No power, no light pollution
Where's your evidence that lights reduce crime at all? If having some lights does reduce crime, where's your evidence that there aren't already more than the optimum number of lights? I know people think that lights reduce crime, but there seems to be little or no proof of it. In fact, what little research I've seen seems to indicate that lights, at least added on top of the lights we already have in cities, do not reduce crime.
In any case, a lot could be done by just aiming the lights at the parking lot itself, rather than at the sky. There aren't that many flying muggers or rapists.
I don't believe that nothing can be done about light pollution while maintaining ground-level lighting, and I honestly doubt that light reduces crime much anyway.
However, even if I'm wrong about that, a better sky view for the majority of the world's population (that's BILLIONS of people) probably is worth a few muggings and even rapes... it takes a stunted soul, or somebody who's never seen a real night sky, not to realize the value. We're not talking about "hobbyists" or "enthusiasts". We're talking about any human being with a functioning spirit.
Wow, what can I say but that was a seriously uneducated answer. How come people can't think that there might be a way to better the situation than to turn off the lights? How about.. maybe.. just maybe.. use light fixtures that don't blast kilowatts of light energy into the sky where they're not needed? Huh? Can you answer that one? In fact, with the same amount of light energy, but directed where it's useful actually makes a much brighter area where people are walking, parking, whatever. To achieve the same level of visibility on the ground, and make the sky darker would actually SAVE energy.
Here is a little excerpt from the article (which you obviously are oblivious to else you wouldn't post foolishness) that seems fitting...
"A burglar who is forced to use a flashlight, or whose movement triggers a security light controlled by an infrared motion sensor, is much more likely to be spotted than one whose presence is masked by the blinding glare of a poorly placed metal halide "wall pack." In the early seventies, the public-school system in San Antonio, Texas, began leaving many of its school buildings, parking lots, and other property dark at night and found that the no-lights policy not only reduced energy costs but also dramatically cut vandalism."
We have enough youth, how about a fountain of SMART?
Those of us from "out in the country" have a different perspective.
Most nights, it's easier to see in the absence of artificial light, because our eyes adapt to the more complete light coverage provided by the moon and stars. City and suburb folks have problems with darkness because of the incomplete coverage of the artificial lights causes ordinary darkness to appear pitch black, and creates shadows causing even more darkness.
Driving at night, I generally prefer to be out in the middle of nowhere, because I can see better with my headlights being the only light source.
Actually, we can improve lighting on earth, save energy, AND improve our view of the cosmos. Our existing nighttime lighting is enormously wasteful. Good lighting design lets you "see where you're going", without blinding you with glare, or destroying your night vision with excessive light. Please visit the International Dark Sky Association which has been working to solve this problem for decades. First, realize that lights that shine up into the sky are helping no one. Any electricity used to illuminate the sky is wasteful and causes light pollution. Properly shielded lights direct light at the ground where it is helpful, instead of at the sky.
Computers obey me.
many women demand more lighting during the night, for reasons of safety.
.7 foot-candles, around 20X the brightness when you are right under the streetlight, but how far outside of the immediate scope of the streetlight can you see? The brighter the bright spots get, the higher the contrast and the less overall visibility you have. My point is that if you keep the brightness low, but take care to light up the dark shadowy spots as well, you can actually see better. Well lit shouldn't be confused with "brighter".
They may be saying "more" light but they probably mean "more even" lighting. You could see better down a street or across a parking lot if it had half the brightness but it was evenly spread, vs intermittent very bright spots. So having it bright as the noon day sun in front of the bar actually makes it worse to walk across the parking lot, unless that is just as bright. If you have every been out in the country at night and you could see moderately well with a full moon (enough to play soccer, I've done it) that was what even lighting at about 0.035 foot-candles gives you as far as visibility. Most streetlights give you about
We are all just people.
Besides turning off lights, just modifying them can make a tremendous difference. Calgary, Alberta used to be one of the brightest cities in the world (despite having a population under a million) and at night you could see about six stars. Most neighborhoods now have lower wattage street lights with flat faceplates. They're much more effective at directing light downwards instead of up into the sky so the overall illumination on the ground is the same. The city saves millions a year in power and you can see constellations again.
What's notable though, is that there is a considerable variation in the result based on where the study was done (and, presumably, the exact difference between the test and control situations, as I haven't went through all the underlying studies myself), with many areas producing negligible changes, or even statistically significant increases in certain types of crime with the introduction of additional lighting. The most simple conclusion is that the lighting has to be sensibly managed: floodlights on every street corner are not necessary, and may even be detrimental. Which means that there is certainly the possibility that the goals of improving the visibility of the sky and the improvement of street lighting (improvement not strictly meaning increase, of course) are not necessarily incompatible.
A few years back on TX State Highway 77 heading north I could see an odd skyglow that I noticed just a few miles north of Raymondville TX. I was interested quickly because there is nothing in the ranch land between Raymondville and Corpus Christi that could be making that much light. Is I continued north, I noted the slowness of the angular change of the light and realized it had to be Corpus. A couple of hours of driving confirmed that the skyglow in this city of absurd light was really visible 120 miles south of here.
This city is totally filled with flood-lit carlots, an incredible amount of freeway lighting (way more per mile than any other Texas city that I've seen), billboard's littering the cityscape all lit from below, and a total disregard for our very unique coastal wildlife. Light pollution is just another example of our culture's unnatural incompatibility with our natural environment.
I always thought it would be nice if we had one day a year where people made a conscious effort to turn off all their lights, like "Star's Day" or some other stupid name so people could have one night a year to keep lights off, but that would inevitably just lead to an increase in crime for that night, so... darn.
Not really, criminals need light too. And as TFA says when San Antonio started turning lights off at night at schools vandalism went down not up.
FalconShould there be a Law?
Look, dude, it's like this. Chicks dig stars. Countless generations of guys got laid by showing chicks stars. What are you gonna do, now that you can't even see the stars? This is all about trying to help guys like you score. Get with the program. Shield your bloody lights.
If you mod me down, I shall become more powerful than you could possibly imagine.
While I'm sure people in Central Park would enjoy the night sky, I empathize with their concern for safety and well lit areas certainly feel more secure. I am suggesting that they would need to travel for a bit in order to enjoy the night sky. Another words, the people who are trying to preserve the night sky aren't suggesting the cities turn out their lights, just shine their lights toward the ground instead of toward the sky. You can drive an hour or so from a small city to see a somewhat dark sky and still see a mighty glow from the cities direction. While I understand the glow can never be eliminated, it certainly can and should be reduced.
One aside - I am familiar with the wind farm being erected in one of the few remaining dark sky sites in the eastern United States. A few changes (like moving them a short distance or using red "safe" lights) would have made them astronomy friendly. While this may not seem important to many, the area was obviously a haven for astronomers from all over the area especially since the park has been working hard to make it even more friendly - like installing astronomical domes with electricity and renting them for a nominal fee. so it goes. end aside.
One final thought - even if there were no benefits like cost savings, energy savings, and better lighting, the idea of dark sky preservation is akin to other environmental concerns. Just because we don't all enjoy sloshing through wetlands or cutting our way through a rain forest doesn't mean those areas shouldn't be conserved. I say the same goes for the night sky. We may not all be awed by the glow of a full moon, a fiery meteor blazing through the sky, or just watching the twinkling of a million stars but we shouldn't take away the opportunity for all of us and future generations from seeing what many of us feel is the most amazing and spectacular thing imaginable: our universe.
What about people WALKING at night?
What about them?
they don't experience glair [sic] (no windshield)
Maybe if you'd RTFA you would know what glare is. Since you won't, let me help you:
"glare bombs": fixtures that cast much of their light sideways, into the eyes of passersby, or upward, into the sky
Nothing at all to do with windshields though I suppose windshields can magnify the effects of glare.
how do you propose they walk without streetlights?
You're the one who proposed that. The post you responded to mentioned reducing their illumination.
Streetlights were intended to reduce crime, and I'd say they do a pretty good job of that.
From the article:
Crawford pointed out a cluster of mailboxes across the street from his garage. The lighting near the mailboxes was of a type that Crawford calls "criminal-friendly": it was almost painful to look at, and it turned the walkway behind the boxes into an impenetrable void. "The eye adapts to the brightest thing in sight," he said. "When you have glare, the eye adapts to the glare, but then you can't see anything darker."
[...]
Much so-called security lighting is designed with little thought for how eyes--or criminals--operate. Marcus Felson, a professor at the School of Criminal Justice at Rutgers University, has concluded that lighting is effective in preventing crime mainly if it enables people to notice criminal activity as it's taking place, and if it doesn't help criminals to see what they're doing. Bright, unshielded floodlights--one of the most common types of outdoor security lighting in the country--often fail on both counts, as do all-night lights installed on isolated structures or on parts of buildings that can't be observed by passersby (such as back doors). A burglar who is forced to use a flashlight, or whose movement triggers a security light controlled by an infrared motion sensor, is much more likely to be spotted than one whose presence is masked by the blinding glare of a poorly placed metal halide "wall pack." In the early seventies, the public-school system in San Antonio, Texas, began leaving many of its school buildings, parking lots, and other property dark at night and found that the no-lights policy not only reduced energy costs but also dramatically cut vandalism.
So there you go. Street lights are good, but if they shine light directly in the eyes of people walking at night, then those people will be unable to see into the shadows, which would be a great place for a mugger to lurk. However, if those street lights are subdued to decent levels and designed to be free of glare then not only can you see your path but your eyes will also still be adjusted for the darkness and you're better able to see what's outside of a brilliantly lit area. There are other benefits too:
Calgary, Alberta, recently cut its electricity expenditures by more than two million dollars a year, by switching to full-cutoff, reduced-wattage street lights.
Reduce the power output of your street lights and save millions. Additionally:
Diminishing the level of nighttime lighting can actually increase visibility. In recent years, the California Department of Transportation has greatly reduced its use of continuous lighting on its highways, and has increased its use of reflectors and other passive guides, which concentrate luminance where drivers need it rather than dispersing it over broad areas. (Passive guides also save money, since they don't require electricity.) F.A.A.-regulated airport runways, though they don't use reflectors, are lit in a somewhat similar fashion, with rows of guidance lights rather than with high-powered floodlights covering broad expanses of macadam. This makes the runways easier for pilots to pick out at night, because the key to visibility, on runways as well as on roads, is contrast.
Want to improve your Karma? Instead of "Post Anonymously", try the "Post Humously" option.
-1, Wrong and Uninformed
/ 054b_exposure_light_and_exposure_values.htm#Light) You can see with a lot less light than you think you can, if you'd just turn out the damn lights.
People walking at night *do* experience glare. First off, lots of folks wear glasses. Secondly, the presence of streetlights, even assuming no stray reflections, *does* affect human vision by preventing the eye from becoming fully dark-adapted. Many lighting schemes actually make things worse by creating very uneven lighting patterns. The eye will wind up adjusting its levels based on those bright areas, and then be completely unable to see in the dark areas.
Naturally, anyone up to no good will be in those shadows where nobody can see, because their eyes are metering for the bright areas.
*Contrast*, not the absolute amount of light, is the real limiting factor here. Two examples:
I was out in the forest today and saw a bird land on a tree branch west of me, backlit by the setting sun. I couldn't tell what it was; it appeared completely black to me because my eyes were adjusted to the huge amount of light coming from the western sky. I can, however, override my camera's automatic exposure setting, and was able to get a picture (at ISO 100, fyi). There was plenty of light to see by, there was just too much light coming from what I didn't want to see. Your eyes don't have an exposure override.
You can also see quite well in a whole hell of a lot less light than you think. I've been in situations where moonlight is actually bright enough to be dazzling (compared to the previous starlight when the moon was obscured); starlight is even enough to see where you're going by.
Starlight is 512 times dimmer than a streetlit street; moonlight is 64 times dimmer. (Reference: http://www.photokaboom.com/photography/learn/tips
Also, studies have been done that show that, when streetlights are removed from neighborhoods, crime actually goes down. Why? Because there are no shadows to hide in, and, if it's really that dark, the boogeyman (who's much less common than you think) won't be able to see you either without a flashlight. My neighborhood is unlit and is in a city with a pretty high crime rate (Tucson, Arizona); I've never felt unsafe because of the lack of streetlights.
Benefits of turning off the lights, since you asked:
1) It saves power. Gobs of power.
2) People can enjoy the natural world, and possibly learn something in the process.
3) Less damn glare, helps drivers and walkers (who can see just fine by moonlight/starlight
4) Astronomy.
5) It has been hinted at that excessive artificial lighting at night screws up people's circadian rhythms and might be responsible for certain sleep disorders, fatigue, depression, etc. This hasn't been shown conclusively yet, of course, and in any case looking at a 14" LCD like I am now is far worse.
One answer is to only run 1/3 of the lights at any given time and randomly change which 1/3 is on. Tests have shown that this tends to REDUCE crime. When the lights are always on, criminals can see where the dark places are and hide there. With random lights, their nice dark hiding place can light up like a parking lot without warning. To a criminal, a light that could come on at any moment is as bad or worse than an always on light.
It's a fairly easy way to save a lot of electricity and help with light pollution. Bonus points if a "scream sensor" immediatly lights the area fully. Double bonus if the surrounding lights light up in an arrow pattern so a police helicopter can spot a problem area visually.
What about if the entire city's lights light up in a marquee display that can be seen from the moon reading "Mugging victim needs assistance here!" ? Brownie points there? No? Dang!
I hate printers.