Light Pollution — from Outer Space to Connecticut

The Milky Way

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“We made lights and nobody really thought about it and this light pollution thing just happened,” said Pete Strasser, the technical director for the International Dark Skies Association.

Light pollution – the artificial brightening of the night sky – is often understood simply as the reason most of us can no longer see the stars.

In fact, 99 percent of Americans can’t see the Milky Way from where they are living according to a World Atlas of Artificial Sky Brightness recently produced by an international research effort led by Fabio Falchi, a researcher at the Light Pollution Science and Technology Institute in Thiene, Italy. That research was recently released in a popular format.

But Strasser and others are also working to explain to the public that excessive light in our environment is not only an aesthetic issue, but also detrimental to our health and the natural environment.

2019 VIIRS Light Pollution Map

“This excessive light has an environmental cost, a lot of species have evolved to depend on darkness,” said Paul Bogard, author of The End of Night: Searching for Natural Darkness in an Age of Artificial Light and an assistant professor of English at James Madison University. 

“Excessive light in the evening, or working the night shift is listed as a potential carcinogen by the World Health Organization. It greatly increases risk for prostate and breast cancer” — Paul Bogard, James Madison University

Migratory birds and sea turtles are classic examples of affected species, Bogard explained, “but all life evolved with bright days and dark nights, so even if we don’t know how light is affecting a certain ecosystem we should assume that it is.”

In terms of the effects on humans, the evidence is clear that excessive light in the evening contributes to sleep disorders and impedes melatonin production.

“Excessive light in the evening, or working the night shift is listed as a potential carcinogen by the World Health Organization. It greatly increases risk for prostate and breast cancer,” Bogard said.

A problem we can solve… maybe

Some states and communities across the country have begun to make small changes to reduce light pollution that are gradually making a difference. In 2001, Connecticut was one of the first states to pass laws aimed at reducing light pollution. Today, 18 states, the District of Columbia and Puerto Rico have enacted similar laws mandating new light fixtures, light bulbs and lighting schedules for state roads and buildings. 

“Even if these new lights are of the less polluting type, fully shielded, minimum lighting levels on the subject to be lighted, shut off when not needed, low-blue content, anyway, they are more polluting than the non-existent previous lighting” — Fabio Falchi, a researcher at the Light Pollution Science and Technology Institute

Unfortunately, simply transitioning to dark sky compliant lighting — lighting that minimizes glare and skyglow with shields — does not diminish the amount of light pollution if there are more light fixtures to begin with.  

“The dark sky lighting efforts are surely helping in giving better and more comfortable, less glaring and less intense, lighting. But, at the same time, new installations are put on the territory, so more light is produced in the night,” said Falchi, “Even if these new lights are of the less polluting type, fully shielded, minimum lighting levels on the subject to be lighted, shut off when not needed, low-blue content, anyway, they are more polluting than the non-existent previous lighting.” 

With current technology, the light pollution changes in intensity are very difficult to detect by satellites, if they are there at all. 

2019 VIIRS Light Pollution Map (Detail)

“Overall in the area near Boston up to the Canadian border, there is not a rapid enough change that I would say confidently that we detect it,” said Christopher Kyba, a researcher at the German Research Center for Geoscience specializing in the ecological impacts of artificial light at night. “The best fit line has a slope with an increase of about 1 percent per year, but the data would also be consistent with a small decrease per year, so it will take a few more years before we will know for sure.”

In addition, the changes are occurring not all at once, but as light fixtures break, pushing any benefits off to a long time in the future. 

For example, The Connecticut Department of Transportation (CTDOT) is responsible 21,000 light fixtures across the state, and nearly half of them have been converted to dark sky compliant fixtures since 2001. 

“CTDOT began converting to full cutoff lighting back in 2001,” said Kevin Nursick, a spokesperson for the department. “We convert semi-cutoff lighting fixtures to full cutoff type when they reach the end of their useful lifespans, typically 40 years, and require complete lighting system replacement when there is the opportunity to revise the spacing between poles appropriate for full cutoff type light fixtures.”

2019 VIIRS Light Pollution Map (Detail)

Although changes on the state level aimed at reducing, or at least mitigating, light pollution are slow, the National Park system and some cities have taken steps to tackle the problem.

In Old Lyme, the public schools have placed all outdoor lighting on timers, and have replaced older lighting with downward-focused fixtures to minimize light scatter, said Ian Neviaser, superintendent of schools in Lyme and Old Lyme.

The problem of planning

The problem is light makes people feel safe, whether it truly does that or not, said Carl Fortuna, the first selectman of Old Saybrook. 

“When the police chief gave input for our new lighting in downtown he wanted more lights. They make his job easier,” Fortuna said. 

In every town in Connecticut there are zoning regulations that dictate the appropriate type and amount of lighting for business and commercial areas, especially parking lots, said Torrence Downes, deputy director and principal planner for the Lower Connecticut River Council of Governments.

“Some have specific measurements in lumens and the like. Others have requirements that light standards have hoods on them that direct the light down toward the ground and require that no light “spill” onto other properties, which is hard to do,” Downes said. 

“When the police chief gave input for our new lighting in downtown he wanted more lights. They make his job easier,” — Old Saybrook First Selectman Carl Fortuna. 

“Light pollution, at least in our region, has been informally discussed to an extent, but I’m unaware of anything formal at this point. I know the CT River Gateway Commission has briefly talked about this issue and whether or not they should try to see if anything can or should be done about it in the lower river valley as a part of protecting the natural and traditional river scene.” 

But as of yet, there have been no measures put into place. 

“The priority in planning for the police and for our town is safety and utility, not light pollution,” Fortuna said. 

Changing a mindset

Some towns, however, have incorporated more extensive standards aimed at reducing, or at least mitigating, light pollution.

“The Westbrook regulations refer to the Illuminating Engineering Society of North America (IESNA) and the International Dark Sky Association (IDA) as the bodies that set such standards. When an applicant comes before the P&Z, they’d have to submit all of the required information and make a demonstration that their plan is consistent with all of the requirements in those regulations,” Downes said. Westbrook’s regulations, “seem to be more substantial than the others … that sometimes happens because a town has a particularly difficult time with a development and its light, so the town reacts by adopting more stringent and specific standards. I think that’s what happened in Westbrook.”

2019 VIIRS Light Pollution Map (Detail of New London/Groton)

But, in order to truly reduce light pollution we need to change the idea that more light makes the world safer, Strasser said. 

“We have this mindset that twice as much light means twice as safe, that more light is always better,” Strasser said. “We need to overcome the innate fear of darkness and the assumption that more light means more safe.”

More light does not mean more safe. Excess light not only contributes to light pollution, but it can actually decrease visibility and falsely make individuals feel safe, Bogard said.   

2019 VIIRS Light Pollution Map (Detail of Groton/Stonington)

“There is no evidence for the idea that we need all this light for safety and security,” Bogard said. “There is growing evidence that shows that light pollution actually contributes to not being safe, including unnecessary glare in your eyes while you’re driving.” 

In fact, there is research showing that brighter and more lighting does not make women feel safer. Instead, women prefer more consistent, layer lighting with multiple light sources that prevents distinct lines between well lit and not lit areas. 

“We have this mindset that twice as much light means twice as safe, that more light is always better,” Strasser said. “We need to overcome the innate fear of darkness and the assumption that more light means more safe” — Pete Strasser, the technical director for the International Dark Skies Association.

Creating downward, more directed facing and softer lighting does not only reduce light pollution and potentially make women feel safer, it also can save a municipality money.

“It’s fiscally irresponsible to have have your tax dollars shining into the sky,” Strasser said. “We have made progress. Most of the lights are designed far better than they were ten years ago. There has been a realization that it’s foolish to spend the money on bad lighting.”

Simple changes like this are effective.

“If we took all the lights that are shining up and pointed them down we would make a huge dent in the problem, likely cut the pollution in half,” Bogard said.

Unfortunately, with the advent of new technology – specifically LEDs – light pollution has not only gotten worse, but also harder to track.

The clash with environmental efforts

LEDs, light emitting diodes, are a cheaper, more energy-efficient light bulb — an apparent win for environmentalists trying to reduce energy expenditure.

However, LED lighting is typically much brighter than incandescent technologies, and LEDs produce light on a wavelength of light, called “blue light,” that is the culprit for most of the health-related effects of light pollution.

“A lot of the first LEDs that came on to the market cities were quick to buy because of the enormous cost savings they brought,” Bogard said. But the light they produced began to disrupt circadian rhythms and melatonin production in humans leading to more sleep disorders and even higher risks of cancer.

In 2016, the American Medical Association released a statement that high intensity LED street lights were harmful. That’s why towns like Old Saybrook are opting for LEDs that produce a better wavelength of light.

“4000 Kelvin is what most towns did when they installed LED lighting. It’s extremely bright and almost blue,” said Carl Fortuna, at a recent Zoning Commission meeting. “In town we chose 3000 Kelvin and installed 1,000 lights with dark sky shields and only got two complaints about brightness.”

Examples of Dark-Sky compliant fixtures (Bob Crelin/Fair Use)

The reason Old Saybrook chose to install lower temperature LED lights was more about cost saving, than about preserving the dark sky, but the effect is the same. 

“The Dark Sky Association told us the best street lighting is no lighting and that’s true for driving, but people want lights for a sense of safety where they might be walking,” Fortuna said. “Our primary reason for conversion is for saving money. In a year, we save $100,000, which isn’t small.”

Blue light is not only harmful to humans, it also prevents scientists from measuring light pollution. The images we so often see depicting light pollution are taken by satellites that were designed to look at clouds.

“People think that we are making improvements, but actually the device used to detect light doesn’t even see the light LEDs produce,” Strasser said. “The hyper-efficiency with LEDs means people can save a lot and make it brighter,” taking away the cost argument that Strasser and others have previously used.