6 ms·

Treat artificial light like other forms of pollution, say scientists

124 points by elsewhen 6y ago

DoingIsLearning 6y ago
I think the awareness problem is that the majority of people in modern society have never trully experienced what it is to _not_ have light pollution. People just assume that the white/orange glow in the sky around a large city is normal and somehow unavoidable. This is to me the best a-picture-is-worth-a-thousand-words explanation I found to make people realize the root-cause of light pollution both for public and private illumination: http://cescos.fau.edu/observatory/Images/floodlight-angles-goodbad.gif http://cescos.fau.edu/observatory/Images/floodlight-angles-g...
- wlesieutre 6y ago
  That “good light” is only all good if you paint the ground with vantablack, otherwise a decent amount if it still bounces back up. So you want to aim all the light downwards, yes, but it’s also important not use more light than necessary.
  - DoingIsLearning 6y ago
    > So you want to aim all the light downwards, yes, but it’s also important not use more light than necessary. Note that the little diagram also dims the light source from 500W to 100W. :) In terms of candela, sure some light will always be reflected upwards but focusing on that really is a case of the perfect is the enemy of the good.
    - wlesieutre 6y ago
      Good point, but I read that as being more that 400W were going into the neighbor's window or up into the sky, and the 100W is intended to keep same light levels as before. If you don't need those light levels, a 50W floodlight would cut the remaining light pollution from upward reflections in half.
  - ben_w 6y ago
    It can make a massive difference. I grew up in village near Portsmouth (UK, metro area population 1.5 million according to Wikipedia), and the night sky was bright orange whenever it was cloudy. I now live in Berlin (6.1 million metro population), and although it isn’t perfect darkness, it is vastly better even though I’m in a built-up part of the city rather than a rural part of the city equivalent to my childhood area in the UK.
- kiliantics 6y ago
  I feel the same way about noise pollution. We just take for granted that public space in cities needs to be uncomfortably loud because most people haven't had it otherwise in living memory. It could be so different and everyone would prefer it if it were. Most loud noises on streets are loud because of all the cars on the street, and also the fact that people in the cars can't hear as well as people outside of cars (necessitating louder horns, sirens, etc.)
- Zak 6y ago
  That picture shows a good start. Not directly illuminating the sky when the illumination is being used on the ground is the low-hanging fruit, but additional measures should be considered: * Use light of lower intensity (candela) to put less illuminance (lux) on what's being illuminated. This is a more precise version of "use a dimmer light", because reducing output (lumens) won't necessarily do that if the light is more focused/directional. * Illuminate fewer places. Street lighting for traffic safety doesn't need to be everywhere; it needs to be where hazards are. * Use alternatives to general illumination. Some road hazards can be marked with reflectors or low-intensity marker lights pointed directly at drivers instead of overhead lighting. * Turn off lights when not in use. Use timers. Use motion sensors. Use buttons pedestrians can press for crosswalks. * Encourage people to use portable lighting rather than fixed lighting. This becomes more effective when there's less ambient light because less light is required to achieve the same contrast with a faraway background.
  - marcosdumay 6y ago
    What I discovered when pushing locally for less lights is that nobody will tell you, but people are afraid of darkness. Expect people to push back on lower light intensity, localized lighting and motion sensors with passion. It doesn't even matter if you get a design that improves security (what motion lights usually do), people will go for the less secure one if there is more light. That's something I have no idea how to solve.
    - Zak 6y ago
      I've noticed that even suggesting it in conversations online. It's not just young children who are scared of the dark. I'm not sure if it can be used to help solve the problem, but I've seen that when places try reduced lighting, the people who live there love the result long-term and do not want to go back. I have family in Sedona, which places strong limits on almost all fixed outdoor lighting, and Boulder, which has removed street lighting in many areas, and those rules are overwhelmingly popular.
  - ourlordcaffeine 6y ago
    A park near me has painfully bright LED lighting on pedestrian footpaths, in a nasty cold blue colour. It destroys your night vision as well. I took a lux meter down the footpath, it registered 75 lux holding it in my hand.
- Raphmedia 6y ago
  This is a huge issue in my part of Canada right now. All those Cannabis greenhouse have illuminated the sky. I live north, away from the big cities and used to be able to see the night sky. Now, all I can see is orange and purple glows. Those greenhouses used to grow tomatoes without any issues, it's only since the shift in product that this started. https://www.cbc.ca/news/technology/cannabis-greenhouses-light-pollution-1.4993407 https://www.cbc.ca/news/technology/cannabis-greenhouses-ligh...
- Devils-Avocado 6y ago
  Its even worse when cities use 6000k pure-white LEDs to eke out an extra 2% efficiency. This color temperature shocks the body into thinking it is still daylight, leading to sleep disturbance.
popotamonga 6y ago
It starts in your room. I have my office in my room. All 10 screens + 4 computers that i need to keep on Sleep mode to keep the state. So many leds everywhere i need to wear a blindfold to sleep. Routers are the worst.
- nullc 6y ago
  Black electrical tape works wonders. I have applied it copiously. With some care on many devices it can be applied invisibly, and it can be removed if you need the led. Outdoors, I've made all my lights activated by motion and door-opening sensors, and have been transitioning to light with less splash. E.g. 592nm LED strip placed 2ft over the ground pointed downwards along walkways, so they only light up the walk way and just provide enough light to see clearly and safely... instead of floods. I find it so much nicer to not have my night vision blown out by my own lights.
  - giantg2 6y ago
    I use the electrical tape when I want to block the light completely. You can use 2 or 3 layers of painters tape if you want to see the status light on a router or similar device. It results in very little light cast, but you can still make out whether it's on or off.
    - bradstewart 6y ago
      You can buy "LED dimming stickers" as well, which are semi-transparent and come in various shapes and sizes. A bit more aesthetically pleasing than painters tape if you care about that. Sounds a bit gimmicky, but they're cheap and I like them.
      - giantg2 6y ago
        Cool, I didn't know they made something specific like that.
      - Zak 6y ago
        I didn't know that was a thing (but why wouldn't it be?). I have four layers of painter's tape over the LED on one of my USB power supplies. I've been tempted to take it apart and solder in a resistor.
nullc 6y ago
Light pollution has come up on HN before, here is my comment in one of those discussions: https://news.ycombinator.com/item?id=21330123 https://news.ycombinator.com/item?id=21330123 I really liked the response by PuffinBlue.
durnygbur 6y ago
If aritifical light in general is pollution, then advertisement produced light, or acustic advertisement would be toxic radiation?
- nullc 6y ago
  Marin has no outdoor advertisements and one consequence is darker skies compared to similarly populated regions.
morsch 6y ago
Yes. And for the love of god do the same for noise, as well.
- zip1234 6y ago
  At least around me, most noise pollution is just from cars. Electric cars are no better than IC cars at speed. I can hear the highway (3 miles away) at all times day or night. Perhaps people can not envision a world with less driving so they ignore this problem.
  - Inthenameofmine 6y ago
    At highway speeds aerodynamic drag creates more noise than the motor itself (externally). So an electric car makes little difference there. Reducing speed reduces noise non-linearly. Therefore electric cars make a big difference for noise pollution in slower city streets. Inter-city travel just needs to be reduced, slowed down, and moved to well built electric rail.
    - morsch 6y ago
      True for aerodynamic noise, but tire noise starts to dominate at speeds as low as 30 km/h[1]. Obviously it's going to vary depending on the car and the road cover. It certainly seems intuitively true from the quality of the sound at the side of a busy city street. EVs do nothing for that and aren't a panacea regarding roadway noise. I've been snuck upon by an EV in a parking lot a couple of times, but never on the side of the street. It would work if we limit the speed within cities to something like 20 km/h, which is something that, yes, we should be doing immediately. [1] https://www.drivingtests.co.nz/resources/are-electric-cars-quieter-than-petrol-or-diesel-cars/ https://www.drivingtests.co.nz/resources/are-electric-cars-q... https://en.wikipedia.org/wiki/Electric_vehicle_warning_sounds https://en.wikipedia.org/wiki/Electric_vehicle_warning_sound... https://de.wikipedia.org/wiki/Reifen-Fahrbahn-Ger%C3%A4usch https://de.wikipedia.org/wiki/Reifen-Fahrbahn-Ger%C3%A4usch
  - morsch 6y ago
    It's cars, yes, and it's also other forms of transportation including railroads and airplanes, it's street cleaning vehicles, leaf blowers, lawn work, garbage collection, inconsiderate people, construction work, etc etc. Not all of these are going to avoidable, but at the moment it's a free externality, there is essentially zero incentive to cut it down and it shows.
SaintGhurka 6y ago
I live in a rural city with a dark skies initiative and I really like it. The north star is easy to find. I can just make out the milky way. Any outside gatherings have a real cozy, old-timey feeling to them. Halloween is especially creepy. The only downside I can think of is that I have to slow way down when I drive at night because I can't see the wildlife standing just off the road - waiting for their chance to jump in front of my car.
goda90 6y ago
We can all start at a local level to solve this by pushing for lighting ordinances: https://www.darksky.org/our-work/lighting/public-policy/lighting-ordinances/ https://www.darksky.org/our-work/lighting/public-policy/ligh...
wenc 6y ago
I read the (quite comprehensive) wiki article [1] to get some perspectives. I think we can all agree that excessive light is undesirable, but there's some subjectivity in determining what constitutes "excessive" lighting. I grew up in a highly urbanized environment (I confess I'm not a nature person), and lighting was very much desirable for safety and for promoting after-hours activity and therefore has a bearing on the economy as well. In northern parts of the world, days get shorter in the winter so artificial lighting can help alleviate a feeling of gloom for some. Some people are uplifted by Christmas lights or by the warm orange glow of a Parisian street lamp, for instance. It sounds like one of those things where different groups need to work together toward a negotiated compromise -- there might not exist an ironclad objective answer as to what's best. [1] https://en.wikipedia.org/wiki/Light_pollution https://en.wikipedia.org/wiki/Light_pollution
onnnon 6y ago
Here is a great presentation about the effects of light at night and melatonin deficiency by Russel J. Reiter, Ph.D., University of Texas Health Science Center. https://www.youtube.com/watch?v=I7YIRqTNmuY https://www.youtube.com/watch?v=I7YIRqTNmuY
6gvONxR4sf7o 6y ago
I hate bright nights because of city lights, but I imagine cities are much safer when they’re not too dark. It’s a shitty trade off, but if that’s the trade, it’s an easy one to make.
- MrAlex94 6y ago
  > There is no clear scientific evidence that increased outdoor lighting deters crimes. It may make us feel safer, but has not been shown to make us safer. https://www.darksky.org/light-pollution/lighting-crime-and-safety/ https://www.darksky.org/light-pollution/lighting-crime-and-s...
Slow_Hand 6y ago
I live in small gated cul-de-sac of duplex houses. In all, there are 20 units where everyone knows each other. Two weeks ago my landlord decided to install a pair of bright LED spotlights on the top of my unit which shine down into the grassy courtyard and illuminate what once felt like a quiet peaceful reprieve from the noisy street on the other side of the tree-line that divides our complex from the rest of the neighborhood. I hate it. Hate hate hate HATE it. I used to enjoy sitting on my stoop in the still evening and listen to the ambient noise. Now what was once a dark, peaceful courtyard is lit up like a parking lot. When I close the blinds on my windows I can still see the light creeping around the edges. I sigh every time I look out them night. I immediately made my dissatisfaction known, but as far as I know I'm the only one who cares. All I got from my landlord was some vague response that someone didn't like the darkness. I don't know why. I've been living here for three years and nobody has complained. Now when I lay in bed at night the ambient light bounces off of the fence outside my rear windows and into my bedroom. I have no idea how to go about convincing my landlord to remove these or dim them considerably without being a huge pain in the ass. That may be what it takes. I just signed a new lease for my place and now I have to live with this. Anyone have thoughts?
- eaenki 6y ago
  Tell them that you’re medically hypersensitive to light and you’ll need to move out and looking to get a refund if he won’t remove the damn light
sunkenvicar 6y ago
The biggest source of light pollution is daylight saving time.

124 points by elsewhen 6y ago

I think the awareness problem is that the majority of people in modern society have never trully experienced what it is to _not_ have light pollution. People just assume that the white/orange glow in the sky around a large city is normal and somehow unavoidable. This is to me the best a-picture-is-worth-a-thousand-words explanation I found to make people realize the root-cause of light pollution both for public and private illumination: http://cescos.fau.edu/observatory/Images/floodlight-angles-goodbad.gif http://cescos.fau.edu/observatory/Images/floodlight-angles-g...

wlesieutre 6y ago
That “good light” is only all good if you paint the ground with vantablack, otherwise a decent amount if it still bounces back up. So you want to aim all the light downwards, yes, but it’s also important not use more light than necessary.
- DoingIsLearning 6y ago
  > So you want to aim all the light downwards, yes, but it’s also important not use more light than necessary. Note that the little diagram also dims the light source from 500W to 100W. :) In terms of candela, sure some light will always be reflected upwards but focusing on that really is a case of the perfect is the enemy of the good.
  - wlesieutre 6y ago
    Good point, but I read that as being more that 400W were going into the neighbor's window or up into the sky, and the 100W is intended to keep same light levels as before. If you don't need those light levels, a 50W floodlight would cut the remaining light pollution from upward reflections in half.
- ben_w 6y ago
  It can make a massive difference. I grew up in village near Portsmouth (UK, metro area population 1.5 million according to Wikipedia), and the night sky was bright orange whenever it was cloudy. I now live in Berlin (6.1 million metro population), and although it isn’t perfect darkness, it is vastly better even though I’m in a built-up part of the city rather than a rural part of the city equivalent to my childhood area in the UK.
kiliantics 6y ago
I feel the same way about noise pollution. We just take for granted that public space in cities needs to be uncomfortably loud because most people haven't had it otherwise in living memory. It could be so different and everyone would prefer it if it were. Most loud noises on streets are loud because of all the cars on the street, and also the fact that people in the cars can't hear as well as people outside of cars (necessitating louder horns, sirens, etc.)
Zak 6y ago
That picture shows a good start. Not directly illuminating the sky when the illumination is being used on the ground is the low-hanging fruit, but additional measures should be considered: * Use light of lower intensity (candela) to put less illuminance (lux) on what's being illuminated. This is a more precise version of "use a dimmer light", because reducing output (lumens) won't necessarily do that if the light is more focused/directional. * Illuminate fewer places. Street lighting for traffic safety doesn't need to be everywhere; it needs to be where hazards are. * Use alternatives to general illumination. Some road hazards can be marked with reflectors or low-intensity marker lights pointed directly at drivers instead of overhead lighting. * Turn off lights when not in use. Use timers. Use motion sensors. Use buttons pedestrians can press for crosswalks. * Encourage people to use portable lighting rather than fixed lighting. This becomes more effective when there's less ambient light because less light is required to achieve the same contrast with a faraway background.
- marcosdumay 6y ago
  What I discovered when pushing locally for less lights is that nobody will tell you, but people are afraid of darkness. Expect people to push back on lower light intensity, localized lighting and motion sensors with passion. It doesn't even matter if you get a design that improves security (what motion lights usually do), people will go for the less secure one if there is more light. That's something I have no idea how to solve.
  - Zak 6y ago
    I've noticed that even suggesting it in conversations online. It's not just young children who are scared of the dark. I'm not sure if it can be used to help solve the problem, but I've seen that when places try reduced lighting, the people who live there love the result long-term and do not want to go back. I have family in Sedona, which places strong limits on almost all fixed outdoor lighting, and Boulder, which has removed street lighting in many areas, and those rules are overwhelmingly popular.
- ourlordcaffeine 6y ago
  A park near me has painfully bright LED lighting on pedestrian footpaths, in a nasty cold blue colour. It destroys your night vision as well. I took a lux meter down the footpath, it registered 75 lux holding it in my hand.
Raphmedia 6y ago
This is a huge issue in my part of Canada right now. All those Cannabis greenhouse have illuminated the sky. I live north, away from the big cities and used to be able to see the night sky. Now, all I can see is orange and purple glows. Those greenhouses used to grow tomatoes without any issues, it's only since the shift in product that this started. https://www.cbc.ca/news/technology/cannabis-greenhouses-light-pollution-1.4993407 https://www.cbc.ca/news/technology/cannabis-greenhouses-ligh...
Devils-Avocado 6y ago
Its even worse when cities use 6000k pure-white LEDs to eke out an extra 2% efficiency. This color temperature shocks the body into thinking it is still daylight, leading to sleep disturbance.

popotamonga 6y ago

It starts in your room. I have my office in my room. All 10 screens + 4 computers that i need to keep on Sleep mode to keep the state. So many leds everywhere i need to wear a blindfold to sleep. Routers are the worst.

nullc 6y ago
Black electrical tape works wonders. I have applied it copiously. With some care on many devices it can be applied invisibly, and it can be removed if you need the led. Outdoors, I've made all my lights activated by motion and door-opening sensors, and have been transitioning to light with less splash. E.g. 592nm LED strip placed 2ft over the ground pointed downwards along walkways, so they only light up the walk way and just provide enough light to see clearly and safely... instead of floods. I find it so much nicer to not have my night vision blown out by my own lights.
- giantg2 6y ago
  I use the electrical tape when I want to block the light completely. You can use 2 or 3 layers of painters tape if you want to see the status light on a router or similar device. It results in very little light cast, but you can still make out whether it's on or off.
  - bradstewart 6y ago
    You can buy "LED dimming stickers" as well, which are semi-transparent and come in various shapes and sizes. A bit more aesthetically pleasing than painters tape if you care about that. Sounds a bit gimmicky, but they're cheap and I like them.
    - giantg2 6y ago
      Cool, I didn't know they made something specific like that.
    - Zak 6y ago
      I didn't know that was a thing (but why wouldn't it be?). I have four layers of painter's tape over the LED on one of my USB power supplies. I've been tempted to take it apart and solder in a resistor.

nullc 6y ago

Light pollution has come up on HN before, here is my comment in one of those discussions: https://news.ycombinator.com/item?id=21330123 https://news.ycombinator.com/item?id=21330123 I really liked the response by PuffinBlue.

durnygbur 6y ago

If aritifical light in general is pollution, then advertisement produced light, or acustic advertisement would be toxic radiation?

nullc 6y ago
Marin has no outdoor advertisements and one consequence is darker skies compared to similarly populated regions.

morsch 6y ago

Yes. And for the love of god do the same for noise, as well.

zip1234 6y ago
At least around me, most noise pollution is just from cars. Electric cars are no better than IC cars at speed. I can hear the highway (3 miles away) at all times day or night. Perhaps people can not envision a world with less driving so they ignore this problem.
- Inthenameofmine 6y ago
  At highway speeds aerodynamic drag creates more noise than the motor itself (externally). So an electric car makes little difference there. Reducing speed reduces noise non-linearly. Therefore electric cars make a big difference for noise pollution in slower city streets. Inter-city travel just needs to be reduced, slowed down, and moved to well built electric rail.
  - morsch 6y ago
    True for aerodynamic noise, but tire noise starts to dominate at speeds as low as 30 km/h[1]. Obviously it's going to vary depending on the car and the road cover. It certainly seems intuitively true from the quality of the sound at the side of a busy city street. EVs do nothing for that and aren't a panacea regarding roadway noise. I've been snuck upon by an EV in a parking lot a couple of times, but never on the side of the street. It would work if we limit the speed within cities to something like 20 km/h, which is something that, yes, we should be doing immediately. [1] https://www.drivingtests.co.nz/resources/are-electric-cars-quieter-than-petrol-or-diesel-cars/ https://www.drivingtests.co.nz/resources/are-electric-cars-q... https://en.wikipedia.org/wiki/Electric_vehicle_warning_sounds https://en.wikipedia.org/wiki/Electric_vehicle_warning_sound... https://de.wikipedia.org/wiki/Reifen-Fahrbahn-Ger%C3%A4usch https://de.wikipedia.org/wiki/Reifen-Fahrbahn-Ger%C3%A4usch
- morsch 6y ago
  It's cars, yes, and it's also other forms of transportation including railroads and airplanes, it's street cleaning vehicles, leaf blowers, lawn work, garbage collection, inconsiderate people, construction work, etc etc. Not all of these are going to avoidable, but at the moment it's a free externality, there is essentially zero incentive to cut it down and it shows.

SaintGhurka 6y ago

I live in a rural city with a dark skies initiative and I really like it. The north star is easy to find. I can just make out the milky way. Any outside gatherings have a real cozy, old-timey feeling to them. Halloween is especially creepy. The only downside I can think of is that I have to slow way down when I drive at night because I can't see the wildlife standing just off the road - waiting for their chance to jump in front of my car.

goda90 6y ago

We can all start at a local level to solve this by pushing for lighting ordinances: https://www.darksky.org/our-work/lighting/public-policy/lighting-ordinances/ https://www.darksky.org/our-work/lighting/public-policy/ligh...

wenc 6y ago

I read the (quite comprehensive) wiki article [1] to get some perspectives. I think we can all agree that excessive light is undesirable, but there's some subjectivity in determining what constitutes "excessive" lighting. I grew up in a highly urbanized environment (I confess I'm not a nature person), and lighting was very much desirable for safety and for promoting after-hours activity and therefore has a bearing on the economy as well. In northern parts of the world, days get shorter in the winter so artificial lighting can help alleviate a feeling of gloom for some. Some people are uplifted by Christmas lights or by the warm orange glow of a Parisian street lamp, for instance. It sounds like one of those things where different groups need to work together toward a negotiated compromise -- there might not exist an ironclad objective answer as to what's best. [1] https://en.wikipedia.org/wiki/Light_pollution https://en.wikipedia.org/wiki/Light_pollution

onnnon 6y ago

Here is a great presentation about the effects of light at night and melatonin deficiency by Russel J. Reiter, Ph.D., University of Texas Health Science Center. https://www.youtube.com/watch?v=I7YIRqTNmuY https://www.youtube.com/watch?v=I7YIRqTNmuY

6gvONxR4sf7o 6y ago

I hate bright nights because of city lights, but I imagine cities are much safer when they’re not too dark. It’s a shitty trade off, but if that’s the trade, it’s an easy one to make.

MrAlex94 6y ago
> There is no clear scientific evidence that increased outdoor lighting deters crimes. It may make us feel safer, but has not been shown to make us safer. https://www.darksky.org/light-pollution/lighting-crime-and-safety/ https://www.darksky.org/light-pollution/lighting-crime-and-s...

Slow_Hand 6y ago

I live in small gated cul-de-sac of duplex houses. In all, there are 20 units where everyone knows each other. Two weeks ago my landlord decided to install a pair of bright LED spotlights on the top of my unit which shine down into the grassy courtyard and illuminate what once felt like a quiet peaceful reprieve from the noisy street on the other side of the tree-line that divides our complex from the rest of the neighborhood. I hate it. Hate hate hate HATE it. I used to enjoy sitting on my stoop in the still evening and listen to the ambient noise. Now what was once a dark, peaceful courtyard is lit up like a parking lot. When I close the blinds on my windows I can still see the light creeping around the edges. I sigh every time I look out them night. I immediately made my dissatisfaction known, but as far as I know I'm the only one who cares. All I got from my landlord was some vague response that someone didn't like the darkness. I don't know why. I've been living here for three years and nobody has complained. Now when I lay in bed at night the ambient light bounces off of the fence outside my rear windows and into my bedroom. I have no idea how to go about convincing my landlord to remove these or dim them considerably without being a huge pain in the ass. That may be what it takes. I just signed a new lease for my place and now I have to live with this. Anyone have thoughts?

eaenki 6y ago
Tell them that you’re medically hypersensitive to light and you’ll need to move out and looking to get a refund if he won’t remove the damn light

sunkenvicar 6y ago

The biggest source of light pollution is daylight saving time.