Slashdot Mirror
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."
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"
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 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...
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.
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.
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.