A Free-Market Energy Blog

‘Light Pollution,’ ‘Sky Pollution’ (International Dark-Sky Association fusses)

By Robert Bradley Jr. -- December 23, 2020

Oh please. Of all the complaints about industrial society, one of the most peculiar is light pollution.

Just for a jingle of silliness before tomorrow’s (happy) Christmas Lights post, and a reminder that only a Malthusian can turn good news and happiness into bad and sorrow, check out this from the International Dark-Sky Association (IDSA). Their website states:

Less than 100 years ago, everyone could look up and see a spectacular starry night sky. Now, millions of children across the globe will never experience the Milky Way where they live. The increased and widespread use of artificial light at night is not only impairing our view of the universe, it is adversely affecting our environment, our safety, our energy consumption and our health.

Of course the IDSA does not mention that (wholly unnecessary) industrial wind turbines have a light issue of their own. “Flashing lights are particularly annoying at night, as is the bright ‘security’ lighting common at wind plant substations in California,” states Paul Gipe in Wind Energy Comes of Age (John Wiley & Sons, 1995). Continuing:

For many rural residents, nightfall is a time of tranquility. Flashing strobe lights atop wind turbines or security lighting will exacerbate any annoyance the turbines’ presence causes residents. (p. 320)

The IDSA pitch about the light “problem” follows (without comment).

What is Light Pollution?

Most of us are familiar with air, water, and land pollution, but did you know that light can also be a pollutant?

The inappropriate or excessive use of artificial light – known as light pollution – can have serious environmental consequences for humans, wildlife, and our climate. Components of light pollution include:

  • Glare – excessive brightness that causes visual discomfort
  • Skyglow – brightening of the night sky over inhabited areas
  • Light trespass – light falling where it is not intended or needed
  • Clutter – bright, confusing and excessive groupings of light sources

The infographic above illustrates the different components of light pollution and what “good” lighting looks like. (Image by Anezka Gocova, in “The Night Issue”, Alternatives Journal 39:5 (2013). Click to enlarge.

Light pollution is a side effect of industrial civilization. Its sources include building exterior and interior lighting, advertising, commercial properties, offices, factories, streetlights, and illuminated sporting venues.

The fact is that much outdoor lighting used at night is inefficient, overly bright, poorly targeted, improperly shielded, and, in many cases, completely unnecessary. This light, and the electricity used to create it, is being wasted by spilling it into the sky, rather than focusing it on to the actual objects and areas that people want illuminated.

How Bad is Light Pollution?

With much of the Earth’s population living under light-polluted skies, over lighting is an international concern. If you live in an urban or suburban area all you have to do to see this type of pollution is go outside at night and look up at the sky.

According to the 2016 groundbreaking “World Atlas of Artificial Night Sky Brightness,” 80 percent of the world’s population lives under skyglow. In the United States and Europe 99 percent of the public can’t experience a natural night!

If you want to find out how bad light pollution is where you live, use this interactive map created from the”World Atlas” data or the NASA Blue Marble Navigator for a bird’s eye view of the lights in your town. Google Earth users can download an overlay also created from the “World Atlas” data. And don’t forget to check out the Globe at Night interactive light pollution map data created with eight years of data collected by citizen scientists.

Effects of Light Pollution

For three billion years, life on Earth existed in a rhythm of light and dark that was created solely by the illumination of the Sun, Moon and stars. Now, artificial lights overpower the darkness and our cities glow at night, disrupting the natural day-night pattern and shifting the delicate balance of our environment. The negative effects of the loss of this inspirational natural resource might seem intangible. But a growing body of evidence links the brightening night sky directly to measurable negative impacts including

Light pollution affects every citizen. Fortunately, concern about light pollution is rising dramatically. A growing number of scientists, homeowners, environmental groups and civic leaders are taking action to restore the natural night. Each of us can implement practical solutions to combat light pollution locally, nationally and internationally.

Help![Be A Eco-Nanny and Eco-Snooper]

The good news is that light pollution, unlike many other forms of pollution, is reversible and each one of us can make a difference! Just being aware that light pollution is a problem is not enough; the need is for action. You can start by minimizing the light from your own home at night. You can do this by following these simple steps.

  • Learn more. Check out our Light Pollution blog posts
  • Only use lighting when and where it’s needed
  • If safety is concern, install motion detector lights and timers
  • Properly shield all outdoor lights
  • Keep your blinds drawn to keep light inside
  • Become a citizen scientist and helping to measure light pollution

Then spread the word to your family and friends and tell them to pass it on. Many people either don’t know or don’t understand a lot about light pollution and the negative impacts of artificial light at night.

By being an ambassador and explaining the issues to others you will help bring awareness to this growing problem and inspire more people to take the necessary steps to protect our natural night sky. IDA has many valuable resources to help you including Public Outreach MaterialsHow to Talk to Your NeighborLighting Ordinances and Residential and Business Lighting.

[Please don’t!]


  1. Jerry Hudson  

    Hi –
    As a life-long amateur astronomer, I’ve experienced increasing difficulty finding “dark sky” in which to enjoy Nature’s nightly shows. Some years ago, I showed slides I’d made of the Milky Way to school children in Washington, D.C. They were astounded to learn that these views could be had out in the country. None of them had ever seen the Milky Way.
    There are of course concerns that our brightly-lit cities bring destruction to some night-migrating birds.
    Mr. Bradley, I much appreciate your campaign to encourage sensible energy uses, and I particularly appreciate your articles showing the folly of wind turbines and vast solar farms. I agree with you that the “dangers” of slightly more CO2 in the air mean we must abandon fossil fuels–is false science only benefiting rent-seekers.
    At the same time, I feel that the Dark Sky Association has done us a favor in encouraging more sensible night-lighting. Street lights in particular are now being engineered in a sensible way, so that they direct light only where needed, and prevent excessive glare. I do think that changes they suggest should be voluntary, not mandatory.
    I think there is an intersection between the sets of sensible energy usage and preservation of the night sky. It is important that people be able to see and admire the cosmos they live in, and, recalling the Psalm: “The heavens declare the glory of God.”
    – Jerry Hudson


  2. rbradley  

    Good points, Mr. Hudson. Thank you for commenting.

    Win-win ‘civil society’ initiatives such as separating sky from lights is one thing; using this end as a pretext for lighting regulation to reduce energy use and ‘saving’ the climate is another. Shame the lighting debate is so politicized.

    Evening lighting is a very good thing for safety and beauty. I personally love city lights ablaze at night. Compare this to the ‘deep ecology’ notion of back-to-nature darkness.

    I have moved from the city to the countryside and can enjoy a starry night. I also am building a retirement home where I will have starry ceilings for visual effect for ‘sleeping under the stars.’

    We need to take the politics out to leave a voluntary win-win with such tradeoffs. But that is not possible with the IDSA in its current form.


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