We don’t need to turn off all the lights. We just need to use light more efficiently. Read more about light pollution, its effects, and how we can reduce it.
What is Light Pollution
The inappropriate or excessive use of artificial light at night (ALAN) is known as light pollution and can have serious consequences for humans, wildlife, and our climate. The sources of light pollution come from exterior and interior building lighting, advertising signs, streetlights, and illuminated sporting grounds.
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.
We encourage a lighting practice that will avoid upward lighting, and reduce excess brightness without compromising safety at night. Unnecessary light, and the electricity used to create it, is wasted by spilling it into the sky, rather than focusing it on to the actual objects and areas that people need to illuminate. Check out this quick one page infrographic for a good visual of poor lighting compared with approved lighting.
The best news is that light pollution can be instantly corrected with a few careful adjustments. Find out how you can help in a few easy steps
John Hernshaw talking about light pollution:
Effects of Light Pollution
On our health, climate, ecosystem & wildlife
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. Artificial lights have caused us to dispute the natural day-night pattern and to shift the delicate balance of our environment. A growing body of scientific and medical evidence is linking measurable negative impacts of artificial light at night on human and ecological environments. Fortunately, simple lighting changes can make positive changes to reduce these effects.
- Disrupting the ecosystem and wildlife
- Harming our health
- Increasing energy consumption
- Affecting crime and safety
1. Disrupting the ecosystem and wildlife
Plants and animals depend on day/night length to regulate growth and reproduction, control predator/prey interactions, and maintain ecological balances. Artificial light at night disrupts all of this by affecting:
- Successful pollination of trees and plants
- Predator-Prey relationships
- Insects mating, pollination and survival affecting crop success , bird survival and insectivores food supply
- Bird migration and flight patterns
- Land and Marine Mammals – feeding, prey distribution and territoriality
- Plants and Trees – pollination patterns
- Wetland habitat – amphibians, such and frogs and toads
- All nocturnal behavioural patterns including mating, reproduction and population survival.
Hutton’s Shearwater (tītī)
The only place in the world that the endangered and endemic Hutton’s shearwater (tītī) breed is high in the Seaward Kaikōura Ranges at elevations between 1200 to 1800 m. These unique birds are very susceptible to artificial light at night and are prone to crash landing in and around Kaikōura, especially during the breeding season (September to April) when birds fly from their mountain colonies to the sea.
These flights take place at night and birds can become disorientated by the artificial light spill of the Kaikōura settlement which lies within their flight path. Often compounded by poor visibility weather conditions, birds mistake the lights for navigational cues and end up colliding with lamp or power poles and lines or just land prematurely within or around the township instead of the sea, predominantly along Kaikōura’s coastal roads. Once on the ground, birds are unable to take off again. As such, they also won’t budge for approaching cars and can end up as roadkill. They also can’t get away from cats or dogs and fall victim to predation. They need help to get some water under their feet and some wind under their wings to get going again. Most birds (except for those dying upon impact) have a good chance to survive if they get rescued, kept safe and released the following day onto water. We are very grateful to the dedicated work of the Huttons Shearwater Trust and the Kaikōura Wildlife Centre
2. Harming our health
All artificial light at night should be used with care, respect and restraint. Light acts like a pharmaceutical drug on the body and it impacts every system. We’re putting our health at risk by something known as Circadian disruption and are only just beginning to understand the consequences. When we’re exposed to artificial sources of blue-white light at night disrupts our body clock and hormonal cycle. This affects sleep, mood and brain function causing negative flow-on effects to our health.
Specific problems with blue-white light are not widely recognised yet but include the following well documented examples in humans: Prolonged exposure to blue/white lighting may show increased:
- Disrupted circadian (day/night) rhythms
- Disrupted sleep and subsequent health deterioration
- Permanent damage to the retinal ganglion (computer screens & mobile phones)
- Stress affecting mental health (nightshift workers)
- Adrenal stress.
Fortunately there are very easy actions you can take to help:
- Be exposed to daylight in the morning and darkness at night for better circadian health and wellbeing.
- Limit blue light exposure from digital screens including smartphones, televisions and computers at night by reducing screen brightness, using night-time apps that lower blue light output or turning devices off. (Visit our useful apps section).
- Replace cooler/brighter blueish-white lightbulbs with warmer coloured yellowish-white lightbulbs.
3. Increased energy consumption
Lighting that shines into the sky and where it is not needed, and is excessively bright, is wasting energy and therefore your money. Quality lighting design reduces energy use and therefore energy dependence. It also reduces carbon emissions, saves money and allows us to enjoy the night sky better.
4. Affecting crime and safety
Lighting is intended to enhance safety and security at night, but ironically excessive bright white lighting can have the opposite effect. 1) does not prevent crime, 2) spoils night vision to see into shadows and 3) temporarily blinds us from glare. Moderate warm lighting avoids this and maintains night vision.
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. A dark sky does not necessarily mean a dark ground. Carefully considered lighting that directs light where it is needed creates a balance between safety and starlight.
In summary:
Easy steps to reduce light pollution
Check your outdoor lights around your home or workplace, and consider whether they are shining into the sky or being switched on when they’re not needed. Follow the International Dark Sky 5 Principles for Community Outdoor Lighting:
Kaikōura Approved Lighting
The Kaikōura District Council recently adopted our proposed draft lighting provision to the light chapter of the District Plan to help minimise and control district light pollution. You can read the full Section 32 supporting report here.
In summary:
Understanding shielding:
