Light Pollution
Table of Contents
Introduction
According to the International Dark-Sky Association (IDA), the term light pollution refers to “any adverse effect of artificial light, including sky glow, glare, light trespass, light clutter, decreased visibility at night, and energy waste.” The IDA further states that light pollution “wastes energy, affects astronomers and scientists, disrupts global wildlife and ecological balance, and has been linked to negative consequences in human health.” - https://kids.niehs.nih.gov/topics/natural-world/wildlife/ecology/lighting/index.htm
It is estimated that billions of dollars are wasted each year throughout the world on light that illuminates nothing on the ground, but instead points straight up. In the USA, it's estimated that 40% of light is wasted.
Bright lights near someone’s front door create an illusion of safety, but not true safety, according to Bogard. That’s because the glare shining into our eyes makes it difficult to impossible to see what is hiding in the deep shadows cast by the light. Proper lighting directs illumination toward the ground, away from the sky and out of the eyes of those nearby.
Keeping communities safe can be made much easier and cheaper by replacing constant lighting with motion lights. This simple change improves safety because it makes it simple for patrols to see if a person or animal is present or not simply by the light sensors activating lights in the area. - https://earthsky.org/astronomy-essentials/paul-bogard-on-why-we-need-darkness/
Deadly Head Lights
Another emerging source of dangerous light pollution is the increasingly bright, high, and improperly coloured headlights on modern vehicles. Instead of softer yellow light, the new LED headlight blast bright white light into the eyes of oncoming drivers. Not only do these produce painfully bright lights that affect wildlife and come through the curtains of sleeping people near roads, but they are increasingly blinding road users, which in turn is driving up the number of night-time accidents.
Adaptive headlights are touted as one solution, by dimming the lights briefly when they sense oncoming traffic, however this is an imperfect system which still blinds fellow road users who aren't using bright lights or are coming towards each other along curved paths, including over hilltops.
Some politicians decided to ignore the lighting side of the problem, and demanded that car windows be tinted darker, which is simply going to make pedestrians, cyclists, and other non-lit road users even harder to see or avoid hitting.
The Importance of Darkness
Darkness promotes human and ecosystem health. Our own circadian rhythms rely on periods of light and dark to help us sleep and produce important chemicals like vitamin D which promotes healthy bones and immune systems. Melatonin production, which is dark dependent, is suppressed when the dark is interrupted at night. “Melatonin is involved in circadian rhythm regulation, sleep, hormonal expression of darkness, seasonal reproduction, retinal physiology, antioxidant free-radical scavenging, cardiovascular regulation, immune activity, cancer control, and lipid and glucose metabolism. It is also a new member of an expanding group of regulatory factors that control cell proliferation and loss and is the only known chronobiotic hormonal regulator of neoplastic cell growth”. [Source]. Artificial light is linked to diabetes, depression, failure at school, and difficulties in concentrating. Some studies indicate a link between artificial light and obesity as well.
More than 60% of invertebrates and 30% of vertebrates are nocturnal, having evolved to find food and mates in uninterrupted darkness.
Wildlife corridors can be compromised by even a single light and so prevent animals from moving across the landscapes.
Scientific evidence shows that artificial light at night can have deadly effects on many species including turtles, amphibians, birds, mammals, insects and plants. Many insects are drawn to light, but artificial lights can create a fatal attraction. Declining insect populations negatively impact all species that rely on insects for food or pollination.
According to research scientist Christopher Kyba, for nocturnal animals, “the introduction of artificial light probably represents the most drastic change human beings have made to their environment.”
“Predators use light to hunt, and prey species use darkness as cover,” Kyba explains “Near cities, cloudy skies are now hundreds, or even thousands of times brighter than they were 200 years ago. We are only beginning to learn what a drastic effect this has had on nocturnal ecology.”
Every year millions of birds die colliding with needlessly illuminated buildings and towers. Migratory birds depend on cues from properly timed seasonal schedules. Artificial lights can cause them to migrate too early or too late and miss ideal climate conditions for nesting, foraging and other behaviors.
Solutions
What You Can Do Presents - "Help Protect Wildlife" a 1:18 minute Video
Make sure that outdoor lighting used colours that interfere less with wildlife such as lights with a red or yellow tint. Light orientation/placement is important too. Shielded lights that face down, whether on billboards or meant for human safety. Other features like solar powered motion detectors can help prevent energy waste and unneeded light pollution, but may startle wild animals if they accidentally trigger the motion detector.
Contribute to Lights Out - Level 1-3 Activism
Turn off lights not needed Consider if late night activity is needed. Companies can save money, reduce ecological impact, and improve employee health simply by eliminating unnecessary night shifts.
Use wavelengths that do not affect wildlife or attract insects (yellow)
Keep lights away from wildlife habitat, especially endangered
Extinguish pot and flood-lights
Substitute strobe lighting wherever possible
Reduce atrium lighting wherever possible
Turn off interior lighting especially on higher stories
Curtains and blinds can reduce light pollution, while increasing privacy and insulation against hot and cold conditions. These solutions all have the added benefit of reducing deadly bird/window collisions.
Frosted windows can reduce cooling costs inside while helping to reduce light pollution outside, by catching the light and redirecting it back where people need it. Frosting and decals can reduce deadly bird/window collisions.
Down-shield exterior lighting to eliminate horizontal glare and all light directed upward
Install automatic motion sensors and controls wherever possible
Reduce, turn off, eliminate, or use alternatives to decorative festive lighting Decorative lighting can be put on timers so that they only function when people are expected to be around to enjoy them. They could also be linked with motion sensors. Timers can reduce their impact, by having the lights only active during times of high traffic, then turning off automatically between 11pm and 6 am when few if any people may be around to enjoy them. Electric festival decorations such as Christmas lights are a very new invention with high environmental cost, and poor recycling infrastructure, (if any in most places) exists to help deal with the waste they produce. Non-electric decorations such as garlands, bunting, or other similar, reusable decorations could replace lights entirely.
Plant Bushes near light sources these as well as carefully placed trees and vines can help reduce light pollution, noise pollution, increase habitat space, and encourage privacy. Some species can even provide food, medicine, and species with thorns or prickly leaves can provide extra security.
Turn lights away from aquatic habitats Lights from docks and communities can trick baby turtles and other endangered species into dangerous areas.
Go to sleep when it's dark by doing this, we not only protect our own health, but reduce our own needed for light use, both saving resources, and making us better neighbors.
Reduce brightness of vehicle lights/don't buy vehicles with blindingly bright headlights not only do these endanger other road users who become temporarily blinded by these lights while driving. Bright headlights increase the chance of animal collisions since nocturnal animals become suddenly blinded and disoriented, hence the phrase "dear in headlights".
Avoid fireworks fireworks not only stress out wildlife and disrupt their natural behaviors. Fireworks terrify pets, causing more run-away/lost pet situations around yearly firework seasons/events. People with PTSD and sensory processing disorders such as people with autism can also suffer severe distress from the loud noises and sudden, bright lights. Alternatives can save resources including money, and reduce pollution caused by exploded firework each year that then wash into waterways. Some examples include:
Cultural dances, costumes, and decorations
Levels 3-4
Re-lamping communities to change roadway and walkway lamps to lower energy LEDs and to redirect the light beams only where needed can have a number of benefits:
Reduce CO2 emissions
Reduce waste: Communities will throw away less bulbs since LEDs last longer
Eliminate mercury: Use of LEDs will eliminate any mercury entering the environment from streetlights
Click the Celebrations & Festivities button to learn about how celebrations and traditions can impact the environment.
Click the Fireworks button to learn how fireworks impact the environment, and what alternatives can be just as fun, without the destruction or toxic chemicals.
Principles of Good Lighting
When converting to new lighting assess quality and quantity of light needed, avoiding over-lighting with newer, brighter technology. Remember that "More does not always mean better!"
Stadiums and other buildings/organizations that use flood lights, or shoot lasers into the sky can disorient migratory birds, causing them to have serious accidents or get lost. They also cause enough pollution so that surrounding communities are unable to enjoy basic natural resources like darkness (which helps us get enough sleep). Light pollution also costs us the ability to see stars, an important part of our herritage.
Since other people's lighting isn't generally something we can control, consider joining the Lights Out initiatives that are becoming more popular as awareness about this problem grows. If there are none in your area, please consider starting one. Every voice can help make a difference! - https://www.audubon.org/lights-out-program
Remember that if you reach out to neighbors, local businesses, schools, and politicians that a polite tone and sticking with facts can go a long way in creating healthy, respectful relationships that will further help promote collaboration. It can be helpful to brush up on our communication techniques. One such technique can be to point out the improved energy/money savings, improved security provided by the addition of technology such as non-blinding lights and motion sensors. People are also more likely to feel invested in eco-friendly changes when they understand that it is part of a group effort.
Design Lit Areas with Wildlife-Friendly Lighting to Reduce Light Pollution & Increase Safety
Wildlife-Friendly Standards
Outside lighting should conform to wildlife-friendly standards set by organizations such as the Florida Fish & Wildlife Conservation Commission, which advises:
Keep it LOW
"Mount fixtures as low as possible. Low mounted fixtures provide more light directly on the ground where it is needed for human safety. This also reduces the potential of the light source or lamp from being directly visible.
Use the lowest wattage or lumen output necessary for the needed purpose."
Keep it LONG
Use long wavelength (greater than 560 nm AND absent wavelengths below 560 nm) light sources such as amber, orange, or red LEDs without the use of filters, gels, or lenses. Using long wavelength light sources is less disruptive to marine turtles than white or multi-colored lights.
Short wavelength light sources, PC Ambers, RGBs, dual lighting boards, and color change options are not acceptable.
Keep it SHIELDED
"The fixture must meet or exceed full cutoff. This is defined as no light emitting above a 90-degree plane.
The fixture must be shielded so that the lamp or glowing lens is not directly visible."
Outdoor lights should be shielded to face down, where they can illuminate the ground for increased safety, instead of blinding people or wasting light into the sky. Lights near aquatic habitats should be faced away from the water, or have some extra shielding to prevent light pollution.
Light orientation/placement is important too. Shielded lights that face down, whether on billboards or meant for human safety
Measuring Light Pollution:
Citizen Science
Citizen Science
"Due to light pollution, the night sky over many of our cities is hundreds of times brighter than a natural, starlit sky. This skyglow hides the stars from our sight and prevents us and all life on Earth from experiencing a natural night, even in areas hundreds of miles away from urban development.
An important part of solving the problem of light pollution is to have a thorough understanding of its magnitude, and a great way to do that is to measure the brightness of the night sky. Thankfully, it is relatively easy to make such measurements, and you can help." - https://www.darksky.org/light-pollution/measuring-light-pollution/
Citizen Science Opportunities
Cities At Night "is a citizen science project that aims to create a map, similar to Google maps, of the earth at night using color pictures with 10 times more resolution than it was available for the public so far.
With this database of almost half a million photographs we work on organizing, cataloging, georeferencing and calibrate for science research purposes."
Community Standards for Reporting Skyglow Observations
Sky Quality Meter
International Year Of Astronomy Lightmeter
Light Ordinances: Laws, Letters, & Community Engagement
International
Lighting Ordinances "On this page, you’ll learn:
North America
USA
Soft Lights Foundation: Law and Regulation This page lists letters written to specific organizations as well as the replies to these letters.
Oceana
Australia
Regulatory Considerations for the Management of Artificial Light around Wildlife "These Guidelines provide technical information to guide the management of artificial light for Environment Protection and Biodiversity Conservation Act (1999) (EPBC Act) listed threatened and migratory species, species that are part of a listed ecological community, and species protected under state or territory legislation for which artificial light has been demonstrated to affect behaviour, survivorship or reproduction."
Light Pollution Laws by Location
This section focuses on which places have laws and ordinances concerning light pollution. This is useful if you want to know your rights and want help holding people accountable for light pollution. If your area doesn't have such laws, then consider it a healthy goal to aim towards and to support.
Europe
Croatia
Czech Republic
France
Italy
Slovenia
South America
Chile
Organizations
Around the world lights out programs and light ordinances are building up steam and acceptance.
International
DarkSky "is a recognized worldwide authority combatting light pollution."
Find your local chapter
"Local chapters are at the forefront of the dark sky movement. Regional volunteers can help you pass an ordinance, provide support, and more."
Online Communities
r/fuckyourheadlights/ "Blinded by those ultra-bright low beams? Join the club. It's not just aftermarket bulbs and misalignment; most new OEM lights pose a threat. Excessively bright headlights impair the vision and visibility of other road users whenever the offending vehicle's front end becomes elevated, and in various weather conditions, regardless of their alignment and source. While these are contributing factors, they distract from our real need: regulations on brightness and color temperature."
Africa
Kenya
South Africa
Stars4All: Southern Africa Adventures Quantifying the sky darkness with TESS photometer
Asia
Japan
国際ダークスカイ協会 東京支部 （IDA東京） IDA東京は、過剰照明が氾濫している国内において、光害を抑え省エネにも配慮した良好な光環境の形成を目指し、環境分野・照明分野・天文分野など様々な専門家が連携・協力して取り組みを進めます。
Taiwan
DarkSky Taiwan "始於星空，直面光害 暗空保護運動發源於1988年代的美國亞歷桑納州的土桑市，國際暗空協會（IDA）成立三十多年來，已成為全球保護夜晚免受光污染的公認權威和領導組織。目前，全球已經有200多個暗空公園地點，包含115座公園、38個社區與20自然保護區等等…完成認證。臺灣的暗空保護主要由觀星社群為首提出倡議，經過兩年多與IDA的交流與各方籌備，2019年合歡山成為亞洲第三座暗空公園，臺灣暗空協會也於2020年底成立，2021年成為IDA台灣分會。"
Europe
NightLight "In the Night Light project regional authorities from The Netherlands, Hungary, Spain, Luxemburg, Denmark, Slovenia and Italy join forces to improve their regional policies for the prevention of light pollution, preservation of dark skies and the sustainable exploitation of dark sky places. The project will introduce packages of regional policy measures for each of the partner regions that will result in a lasting reduction of light pollution, the designation of nature areas where dark skies are protected and the introduction of new services and facilities to attract eco-tourism to these dark sky areas."
Austria
Croatia
Naše Nebo "Pozivamo sve gradove i općine da se priključe ovoj akciji podizanja svijesti o klimatskim promjenama, podrže nastojanja oko očuvanja prirodnog okoliša i održivog razvoja te nastojanja za smanjenje svjetlosnog onečišćenja."
Cyprus
DarkSky Cyprus "The Cyprus Astronomy Organisation's work includes initiatives to protect the night skies and fragile ecosystems.
We educate communities and public officials about light pollution and provide solutions and resources through our public outreach programs
Lucky for us who live in the island of Cyprus. An island of excellent weather conditions and clear night-sky for 280 to 300 days out of 365. Even if we’re experiencing problem with the light pollution from the cities, a 40 minutes of an easy road will bring you at a very dark-sky spot near the mountains.
Our aim is to utilize such sites for astronomical purposes, but also to protect them from light pollution.
We're currently working on a project to create and establish a special place especially for observational astronomy. It is located at the foot of the mountain Troodos, 40 minutes from Nicosia and Limassol. At this stage there are members from different countries who came to astronomical observation events. Many astronomers in the world are facing problems, as mentioned above, so they cannot make regular observations in their countries."
Czech Republic
Germany
Greece
DarkSky Greece "Στο darksky.gr μπορείτε να ενημερωθείτε για το πρόβλημα της φωτορύπανσης, τις επιπτώσεις της στην αστρονομία, το περιβάλλον και τον άνθρωπο. Σε αυτόν τον δικτυακό τόπο θα φιλοξενούνται νέα για τη φωτορύπανση καθώς και οι προσπάθειες αντιμετώπισής της."
Hungary
Ireland
DarkSky Ireland Responsible lighting through education and the development of a national policy and strategy in the absence of legislation.
Italy
Malta
DarkSky Malta / Light Pollution Awareness Group (LPAG) "The LPAG has been recently formed within The Astronomical Society of Malta.
Its aims are to create first of all an awareness about light pollution and its adverse effects on man and on local fauna and flora. This will be done by the publication of several leaflets about the subject, together with the publication of an update to the guidance for outdoor lighting booklet which the Society had issued back in 1995.
Many outdoor lights waste energy by spilling much of their light where it is not needed, such as up into the sky. This waste results in high operating costs.
L.P.A.G. has come up with a set of guidelines for the protections of our night skies. Click here to read the guidelines."
Switzerland
DarkSky Switzerland "Für umweltschonende Beleuchtung und den Schutz der Nacht" Site in Deutsch, Français, and Italiano.
United Kingdom
North America
Lights Out Niagara (wasn't sure if this was for Canada, the USA, or both)
Canada
FLAP "We protect birds from a deadly leading threat: collisions with buildings"
USA
Lights Out Programs Across North America List of names, addresses, and links.
Lights Out Heartland "Every year, billions of birds migrate north in the spring and south in the fall. The majority of the birds fly at night, navigating using the Moon, stars and night sky. As they pass over big cities, they can become disoriented by bright artificial lights and sky glow. An estimated 600 million birds in the U.S. die each year from collisions with buildings. A study published by Cornell Lab of Ornithology ranked metropolitan areas in Missouri, Kansas and Illinois where, due to a combination of light pollution and geography, birds are at the greatest risk of becoming attracted to and disoriented by lights and crash into buildings.
We hope that you will learn more about our program by reviewing our website and join our initiative to create bird-friendly communities."Soft Lights Foundation "is the leading activist organization dedicated to restoring the natural night resource and protecting people from the harms of LED light." You can sign their petition here.
Arkansas
Arkansas Natural Sky Association (ANSA) "is an Arkansas Unincorporated Nonprofit Association and the International Dark-Sky Association's Arkansas affiliate. The Association is governed by a Steering Committee. Membership is open to the public, but membership is not required to become involved, which can be done by joining our Volunteer Community."
Colorado
Delaware
Georgia
Illinois
Kansas
Missouri
Pennsylvania
Texas
México
Species Impacted by Light Pollution
The following is a small but growing list of species impacted by light pollution.
By combatting light pollution, we can not only lower wasted emissions, but help bring these species back and rebalance our ecosystems.
Grants & Funding
Europe
UK
National award schemes There are a number of key organisations offering grants and advice to community based projects e.g.
Big Lottery Fund "Groups can apply to us for funding under £20,000, or over £20,001, depending on what they want to do."
Heritage Fund "We fund projects of all sizes that connect people and communities to the UK’s heritage."
Further Reading
Our Darkness page focuses more on the animals affected by light pollution and how to help them.