Light pollution is so widespread and common to urban life that we hardly give it a second thought. Yet there are valid concerns about our well being when it comes to light pollution. Unnecessary outdoor lighting wastes energy and contributes to greenhouse gas emissions. Constant exposure to artificial lighting may interfere with human metabolism and sleep. Luckily, light pollution is reversible. Take action to rein in your own light practices and spread the word to others.
So, what is light pollution?
Light pollution also known as photopollution, is excessive and/or obtrusive artificial light. It is a major side-effect of urbanization, and has been blamed for compromising health, disrupting ecosystems (including bird migratory patterns) and spoiling aesthetic environments.
It can take various forms and may come from various sources:
The Royal Astronomical Society of New Zealand outlines the following diffuse and point sources:
- Glare: The excessive contrast between bright and dark areas in the field of view.
- Light trespass: Unwanted light (spill light), for example from adjacent properties and activities.
- Light clutter: The excessive grouping of lights, for example in roadside advertising which can prove a dangerous distraction to motorists.
- Excessive lighting: Excessive lighting wastes energy and money.
- Sky glow: A combination of reflected and refracted light within the atmosphere. A major effect of sky glow at night is to reduce contrast in the sky. This is the most pervasive form of light pollution and can affect areas many kilometres from the original light source.
- An absence of darkness: Artificial light makes experiencing natural night-time lighting conditions impossible in many parts of the country.
- Light spectrum: Inappropriate colour temperature for ecological and human health and astronomy.
See what global light pollution looks like with this map.
Follow these simple steps to curb your light pollution
1.Consider replacing outdoor lights with low-glare fixtures.
The design of the physical environment plays an important role in shaping the way people live, work and play, engendering a sense of belonging and pride in the community. How your home feels is more important than how it looks. Bright outdoor lights create glare rather than warmth and can have adverse affects on your sleep.
Adding motion sensors to non-essential lights means the area around your home can remain naturally dark, helping to enforce a natural sleep pattern through exposure to the natural light levels.
Aim your outdoor lights downward. This helps prevent stray light from entering the atmosphere and shining into bedroom windows disturbing sleep.
2. When you are in your home, turn off lights you are not using.
There is no need to have your entire house lit up at all times. Turn off the lights in rooms that are not currently in use. Turn off lights when you exit a room, even if you are only leaving the room for a brief period of time and try making signs to place near light switches to remind everyone to do the same.
Turning off lights when not in use is as important for conserving energy as it is for reducing light pollution. Conserving energy is not only beneficial for the environment, but also for your power bill.
3. Use “warm” lights in your house lighting.
“Cool” or lights on the blue end of the spectrum are harsh and more noticeable from a distance. Warmer lighting, such as those with yellow or orange hues, are less harsh on environments but also improve sleep patterns.
Lights on the blue end of the spectrum, such as that emitted from your mobile phone is adverse to a calming sleep. According to the Scientific American, the light from our devices is “short-wavelength-enriched,” meaning it contains more blue light than other wavelengths, and affects our levels of the sleep-inducing hormone melatonin more than any other wavelength.
So as you can see, there are practical steps you can take to reduce light pollution. You may even be surprised how much you enjoy the reduced light levels. Take this opportunity to relax in low light or perhaps, even get reacquainted with the stars.