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Image credit: Geoff Livingston
1150 words / 5-minute read
When you hear the word "conservation", what comes to mind? Maybe turning off a running water tap, or upping the thermostat a little in summer. We take such actions for a variety of reasons, such as lowering bills and reducing our dependence on natural resources. But what motivates us to do these things in the first place? And how might it be different when the focus of conversation is something intangible?
We sometimes encounter the idea of "conserving" dark night skies. The idea has been around at least since the early 1970s, taking the form of the protection of naturally dark places by astronomers.  At the start of the 21st century, the environmental conservation world began to take note. Now, at many parks and on protected lands, conservation professionals monitor the "quality" of night skies alongside the quality of air and water.
Those professionals often refer to the "objects" of their conservation efforts. Air and water are easy to understand as "objects". But what about the beauty of a natural landscape or the historical significance of the ground? Can a dark night sky itself be a "conservation object"?
Value and threat
Understanding that requires a little background in conservation theory. Conservation related to "resources" which are usually natural in origin. Some resources are renewable, and some are not. Some renewable resources lose their renewability due to human interactions. Humans consider something a resource because they assign some kind of value to it. Resources become objects of conservation when one or more influences threaten their integrity. The combination of value + threat makes the "object" a target for conservation to ensure it continues to exist.
In naming the conservation object here, we should consider the value and the threat. It also pays to think about the problem more broadly: the resource is best described as "nighttime darkness". A dark sky is a subset of that, because it's only half the landscape. The other half is the ground, where most concerns about harm to biology (including humans) exist.
Nighttime darkness has value along several dimensions. One model holds that objects fall into a space defined by value to individuals, value to groups, and scientific value.  The farther an object is from the origin of this space, the more likely it is to be considered a conservation object.
(Figure adapted from .)
People clearly find value in nighttime darkness. For example, dark night skies have inspired humans to create great works of art. Some people report meaningful psychological and/or religious feelings when accessing dark skies. And there is evidence that regular exposure to nighttime darkness supports a sense of wellbeing and better health outcomes. At the same time, dark nights have an "impersonal" value at a level higher than the individual. The relationship between natural darkness and humans is a kind of intangible cultural heritage. It also relates to the welfare of wildlife and ecosystems that depend on it. And as "reservoirs" of darkness, naturally dark places are important laboratories for scientific studies. Some sciences like astronomy are dependent on access to them.
The threat to this object of value is artificial light at night. It's not new; for at least 2,000 years people have observed the effects of light at night on plants and animals. The significance of that harm increased with the introduction of electric light about 140 years ago. And an understanding of how it affects people has matured only in about the past half-century. The threat to nighttime darkness materializes in the form of light pollution, which now affects much of the world. [3,4]
From theory to practice
This may all seem like an academic exercise. But there is a practical benefit to the kind of analysis that identifies natural darkness as a conservation object. Various bodies of knowledge, from environmental science to philosophy and ethics, help inform how to conserve it. The experience of practitioners over several decades shows us the best practices. And environmental history shows how framing the nature of the object leads to the most effective forms of advocacy and activism to protect it.
The trajectory of a conservation approach can go one of three ways: it can improve the value of the object; "hold the line" in its current state; or see the degradation of the object leading to a loss of value. How it evolves in depends on the severity of the threat; how the nature of the threat changes over time; and how the perceived value of the object responds to the threat. Rarely is all this determined in advance. Rather, conservation is an open system that interacts with the world in complex ways.
(Adapted from Figure 2 in .)
Lastly, what does this teach us about protecting the things we care about? Conservation of a resource involves a certain kind of "value proposition". It asks the question: why should people care? People and groups who have been deprived of natural darkness, often for generations, might not find value in the resource. They might decide that conservation efforts are too difficult, and the rewards of success too far away in the future to matter today. In short, they might decide that the perceived risks outweigh the supposed benefits. How can we change this?
To increase the value proposition, we must show clear benefits resulting from the behavioral changes needed to achieve conservation of the object. That may be the positive impacts of astrotourism on stagnant rural economies. Or it may be improved ecosystem resilience in the face of global climate change. People may come to see access to nighttime darkness as a factor that improves their quality of life. It could even be as simple as a desire to leave the world in better condition for the benefit of the generations that follow us.
The path to protection
When people come to see the value proposition of conserving nighttime darkness, they are more likely to support the changes that will achieve its goals. Often these behavioral "nudges" are small, reducing the sense of investment in what may be seen as an uncertain outcome. Yet, unlike in the case of other forms of environmental pollution, improvement of the resource is immediate following actions taken to reduce light pollution. Seeing immediate results can help sustain and further conservation efforts once conditions begin to improve.
The adoption of nighttime darkness conservation by environmental professionals is an important milestone along the road to saving dark night skies for our children and grandchildren. Achieving that goal involved elevating the resource to a high state of value and identifying a clear threat to its long-term stability. From there, the tools of the conservation trade can be adapted to protect it.
Many groups are now considering how they can write these ideas into their plans and actions. We can help articulate the value proposition to stakeholders and devise strategies for dark-sky protection suitable for any size business or organization. Contact us today to find out more.
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880 words / 4 minute read
This month we shine a figurative spotlight on scientific research into light pollution and dark skies. As a field of academic study, it is growing fast. In the past decade it has brought researchers together across many different disciplines and spawned its own conference series.
Two events in June highlight how prominent light pollution research has become. We recap them here.
Light Pollution: Theory, Modeling and Measurement (LPTMM) 2022
LTPMM is a series of scientific conferences that began in 2013. It alternates years with the Artificial Light at Night (ALAN) series. The COVID-19 pandemic pushed both conferences online in recent years, which enables more people to take part. LPTMM 2022 was held during 21-24 June with over 100 participants.
A new feature of this year's meeting was a "roundtable" discussion at the start of the first three days. Instead of a single plenary speaker, the organizers invited short, expert presentations on three topics representing challenges of the next ten years: measuring and monitoring light pollution; the environmental sciences; and public health. Open discussions among all participants followed.
The expert presentations highlighted the seriousness of the global light pollution threat. Franz Hölker (Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Germany) noted that light pollution is now widespread and represents "a significant threat to global biodiversity". Prof. Kevin Gaston (University of Exeter, UK) compared light pollution to climate change in the sense of how much it is disrupting the environment. "Things are happening at very low levels of light," he said in reference to that biological disruption. There is no known 'break point' below which we shouldn't be concerned.
We heard some interesting science talks as well. These included reports on new advances in measurement of light pollution. In addition to new sensors that look in many directions at once, there are recent innovations in putting cameras on drones and balloons. The National Park Service's Natural Sounds and Night Skies Division introduced a new website that serves its many measurements made on protected public lands. And the creators of GAMBONS, an online model of natural night sky brightness, showed a new version of their website incorporating data from the European Space Agency's 'Gaia' mission.
Other researchers are working in subjects in and around lighting science. Sibylle Schroer (IGB) stressed the need to consider "sufficiency" of lighting and not focus exclusively on energy efficiency. To that end, Prof. Salva Bará (Agrupación ÍO, Galicia) showed results of a calculation indicating that, in a perfect outdoor lighting installation, the average viewer only senses about one out of every 22 million photons. The need for more efficient lighting design is very clear.
Some recurring ideas emerged during the meeting:
(1) There seemed to be a broad consensus that a need exists to standardize what we measure and in which units. Although there is yet no agreement on those points, researchers see the value of doing so, especially to be able to better inform policy makers.
(2) We need to get a better handle on the actual amount of outdoor light exposure participants in health studies receive. Most current efforts estimate this from satellite measurements of light pollution.
(3) Researchers should take a broader view of the impacts of light pollution on the natural environment. Prof. Gaston referred to this as a 'macroecology' of artificial light at night. That involves better predicting the large-scale ecological impacts of light at night; determining how light pollution interacts with other pressures like climate change; and better understanding which kinds of lighting mitigations work best to reduce ecological impacts.
Researchers and activists will next meet at the 8th International Conference on Artificial Light At Night, to be held in Calgary, Canada, next August.
IDA 'State Of The Science' Report
We recently worked with the International Dark Sky Association (IDA) to author a report summarizing what we know about the science of light pollution. The report, "Artificial Light at Night: State of the Science 2022" was the result of two years of work.
We surveyed almost 4,000 scientific papers and reports in the Artificial Light At Night Research Literature Database. The goal of the report is to empower dark-sky advocates and the public with reliable, factual, understandable information about light pollution.
The report condenses the current scientific consensus on how artificial light affects seven key topics. These are the night sky; wildlife and ecology; human health; public safety; energy use and climate change; social justice; and satellite light pollution. Where gaps exist in our knowledge, we highlighted them as targets of future research.
"State Of The Science" finds the world transformed by electric light in less than 150 years since its introduction. Evidence exists for significant impacts in all the topical areas covered by the report. But it also identifies instances where the evidence is ambiguous and requires further scrutiny.
We used illustrations from the papers we cite to make certain points clearer. Also, we wrote the report in language that avoids jargon to make the contents understandable to more readers. Besides its value to dark-sky advocates in their education and outreach efforts, the report is suitable as a "leave-behind" for lawmakers and their staffers.
For a closer look at how and why we created this report, click here to watch a March 2022 presentation to the IDA advocate community.
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Credit: Ivan Radic / CC-BY-2.0
968 words / 4 minute read
Outdoor artificial light at night has transformed the Earth in ways we still struggle to understand. Despite its many social benefits, wasted outdoor light at night harms the environment and people. In that sense, the issue is a pollutant (outdoor light used with little caution) contaminating a natural resource (nighttime darkness).
Light and Western environmental law
This idea is not news to anyone who has followed the environmentalism movement of the past half-century. Instances of major legislation protecting the environment from pollution have followed a more or less standard script: First, quantify the significance and the severity of the problem. Next, determine a "safe exposure" threshold. And finally, write policies that establish penalties when those thresholds are exceeded. This approach to reducing pollution has achieved success in many parts of the world.
So far, this model doesn't apply well to how the world treats light pollution. There is yet no agreement about what a "safe exposure" is for people, although we know that even tiny amounts of artificial light at night are hazardous to wildlife. For now, the conventional approach to reducing pollution isn't working.
Instead, the usual way that legal jurisdictions try to limit light pollution is by placing limits on the 'source' side of the problem. That is, they enact laws requiring shielding of lights or prescribing limits on light intensities. Some may limit the spectrum of the light to reduce specific environmental harm. Limited evidence exists that this sometimes works to reduce light pollution. But we can't yet point to any specific outdoor lighting policy and say that because of the policy light pollution changed by some amount.
Maybe we need to rethink altogether our notions about how to regulate outdoor lighting. By and large, our policies still cater to human needs first. And our current 'sustainability' paradigm mostly prioritizes the economy and society over the environment. Furthermore, light pollution doesn't respect political boundaries. Light at night emitted in one area can easily affect another place hundreds of kilometers away.
Investigating policy alternatives
At the same time, dark skies are a manageable resource. The problem we confront is in search of a regulatory solution, not a technical one. What if the center shifted toward the nighttime environment itself, independent of whether any humans were around to experience it?
That's an idea that first took root in Western society about 50 years ago in the form of a legal framework called the "Rights of Nature". Its proponents suggested the best way to save the environment was to give a kind of legal status to nature itself, with human agents acting on its behalf. The Rights of Nature holds that nature has the right to remain in its inherent condition and be remediated if damaged. People not affected themselves by environmental degradation also have a right to bring suit on its behalf. It implies that natural resources are kind of public good worth managing in trust for the benefit of future generations.
A famous example of this is the Whanganui River in New Zealand, sometimes known as "the river that owns itself". In March 2017, the New Zealand government conveyed a legal status on the river like that of a corporation or a natural person. Two officials, one from Māori and the other from the NZ government, represent the river's interests in court.
Māori 'talk' to the Whanganui River in New Zealand, which they call Te awa tupua. It is regarded by Māori as taonga, a special treasure, and now has its own status under NZ law. Photo by Neeta Lind / CC-BY-2.0.
Like others, this approach has its benefits and drawbacks. On the "pro" side, it moves humans out of the center of how the issues are framed and insists that decisions we make that impact nature should focus on nature more. On the "con" side, this view has no historical foundation in Western law, which considers nature to be a form of property its owners are free to exploit. Environmental laws protect resources from pollution, but only to the extent any harm to them affects people in adverse ways.
Giving a (legal) voice to the night
So what might a dark-skies implementation of the Rights of Nature look like? It could begin with legislatures enacting resolutions identifying the values associated with dark skies. That value, enshrined in law, could one day prompt reconsideration of the current view of darkness as a resource whose exploitability is endless.
Going a step further, legislatures could insert statements of intent into bills, bylaws and ordinances. This provides guidance to judges who interpret laws. In turn, that could build up a body of case law that points toward an elevated legal status for the night. It can also connect dark skies to issues like social and environmental justice.
New international treaties may advance the idea of intrinsic rights for the nighttime environment. Treaties signed by 'coalitions of the willing' help establish the limits of acceptability. They can also impose pressure on holdout countries that brings their own national laws into eventual compliance.
Lastly, there are clear affinities between these issues and those important to Rights of Nature initiatives around the world. Joining forces with organizations dedicated to protecting nature can elevate the conversation. It will be important to keep dark skies in the foreground as world legal thought evolves around issues like climate change, habitat loss and threats to biodiversity.
Dark skies in the Rights of Nature context is a very forward-looking concern. Any gains are likely in the far future. For now, it offers a new way of framing the problem of light pollution and suggests innovative ways forward. There are many ways to address light pollution on the local level that leverage the many existing tools at our disposal. We can help clients navigate these challenges and come up with effective solutions. Contact us today to find out how.
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Credit: Virginia State Parks
923 words / 4 minute read
The natural night sky looms large over humanity's past, present and future. Once a province only of the gods, the night sky is now our portal to understanding the universe. Light pollution, a phenomenon of only the last two centuries, now threatens to separate much of humanity from the starry heavens. Should access to a night sky unspoiled by light pollution be reserved only to those who live, or can travel to, rural places? Or should we aspire to a world that affords such access to all?
Under one sky
There are many reasons why people work toward preserving dark night skies. As our window on the cosmos, the night sky is the source of information that fuels astronomy. "Astrotourists" travel around the world unique experiences under the stars. Closer to home, casual stargazers find recreation opportunities under almost any skies.
We know that actions taken to protect the night sky have myriad benefits on the ground, too. Light pollution has negative effects on most wildlife species. Darker places, on the other hand, offer refuge to plants and animals already stressed by habitat loss and climate change. Better outdoor lighting can also improve public safety while using less energy. Taken altogether, these are powerful reasons for reducing light pollution.
But if we set all that aside, there's an equally strong argument that access to the night sky has a prominent place in what it means to be human. Dark night skies were once accessible to all people in the world, and they inspired great works of art, literature and music. The sky is part of the cultural heritage of all humanity. It's one of the few aspects of the natural world that we all share.
As such, it may be true that all people should have equal access to the stars. If so, then light pollution is more than an environmental threat. It interferes with access to an important cultural resource.
Cheomseongdae, an astronomical observatory in Gyeongju, South Korea. Built in around the 7th century CE, it may be the oldest surviving such structure in the world. Photo by Flickr user ecodallaluna.
An international view
To date there is little recognition in law for these ideas. Many of the assertions about humanity's rights come from the United Nations. A few UN-sponsored activities have either implied a right to access the night sky or called for it outright. For example, Article 1 of the the La Laguna Declaration of 1994 asserts that “persons belonging to future generations have the right to an uncontaminated and undamaged Earth, including pure skies.”
The United Nations Educational, Scientific and Cultural Organization (UNESCO) held a conference on these ideas in 2007. The resulting "Declaration in Defense of the Night Sky and the Right to Starlight" considers "an unpolluted night sky" to be "an inalienable right of humankind". The Declaration elevates the right to starlight to a place alongside "all other environmental, social, and cultural rights".
Another relevant UN statement is the 1972 UNESCO Convention for the Protection of the World Cultural and Natural Heritage. This action established the UNESCO World Heritage Programme. It has applied the label to astronomy sites, both ancient (e.g, the Chankillo Archaeoastronomical Complex, Peru) and modern (e.g., Jodrell Bank Observatory, UK). But so far it has resisted designating the night sky, or nighttime landscapes.
The night sky is both cultural and natural heritage. It transcends national boundaries; there is, for instance, no "American sky" or "Chinese sky" belonging to those cultures alone. And it’s not a problem that the night sky, or space, is an “intangible” thing. UNESCO already recognizes such forms of cultural heritage. Under the existing framework, the night sky could receive the same kind of recognition and protection as any object the UN recognizes.
The uses of outer space are now beginning to affect the quality of night skies on Earth. The space over our heads is increasingly crowded, with the planned launch of hundreds of thousands of new satellites in the 2020s. These satellite "megaconstellations" are gradually transforming the appearance of the night sky. And yet the main international treaty governing the use of space is silent on the subject. When the nations of the world signed the Outer Space Treaty in 1967, these concerns were on no one's radar.
Photo by Warwick University
Stars for all humankind
Threats to human health from the pollution of air, water and soil can dictate measures to reduce those pollutants. There is an emerging consensus among researchers that nighttime darkness is key to our health and wellbeing. Reasons exist suggesting that regular access to nature is good for us. And there's even evidence of disparities in the way light at night affects poor neighborhoods and communities of color.
Does nature itself have some say in all this? Nations have begun to recognize certain "rights of nature" that can lead to rehabilitation of environmental harms. That's true even when no real person has suffered any obvious injury. Touted as a legal means to combat climate change, it's possible the same principles apply to night-sky conservation.
In an era when so much divides us, whether neighbor versus neighbor of culture versus culture, the night sky is something we all share. Over time, we may come to realize that seeing the stars is not only something of value to people who can afford to escape the nighttime glow of the world's cities. Rather, it's an integral part of the human experience that should be available to all. Solving the global problem of light pollution is simple and cost effective. And it just might make all of our nights a little better.
There are many ways to bring back the stars to the places where we live, work and play. Contact us today to find out how we can help.
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742 words / 3 minute read
Got a railroad ticket,
As a musical genre, the origin of the blues is clear: it emerged from the the Deep South of the United States in around the 1860s. The source of its name refers to melancholy and sadness, the lyrical topics of many blues songs. According to the African American anti-slavery activist Charlotte Forten Grimké (1837-1914), blues songs "can't be sung without a full heart and a troubled spirit."
There are lots of influences around us that may give us the blues. Short-wavelength, or "blue", light at night is one of them. Many modern light sources are blue-rich, which can lead to a host of problems. As light-emitting diode (LED) technology continues to displace earlier ways of making light at night, these problems become more common.
How much blue?
The amount of blue light a lamp or light source emits depends on many factors. We can compare sources by determining how much of their light they emit over some range we call "blue". For our purposes here, we define "blue" wavelengths to be in the range 380 to 520 nanometers. Using information about many common lamp types, we can arrange the sources according to what percentage of their light emissions fall within this range.
Note that natural sources of light in the outdoor environment, such as the Sun and Moon, are remarkably blue. Because blue light scatters more in our atmosphere than other colors, our sky is blue during the day rather than some other color.
Blues in the night
Much of Earth's biology has evolved to expect lots of blue-rich light during the daytime and little or none of it at night. As a result, many species are very sensitive to blue light exposure at night. Consider, for example, that blue light exposure changes the balance of food webs in rivers and streams. In the lab, researchers find blue light stresses or even kills both human and primate cells.
The effect that makes the sky blue during the daytime can make the nighttime glow of cities worse, especially at large distances. If one holds the light output of a city constant but shifts the colors of its lights toward the blue, the night sky over the city gets brighter. White LEDs replacing earlier sodium lamps can add up to 10-20% to skyglow.
Blue light can also change how people perceive light on the ground. As lighting shifts toward more blue, it tends to cause more perceived glare that may, in turn, cause traffic safety problems. This is especially true for older drivers, as light scattering in the aging eye becomes important.
How to kick the blues
Despite these concerns, it's not all bad news. People need blue light exposure at certain times of day to ensure good health. It helps maintain a healthy circadian rhythm and contributes to sleep quality. At night, there should be little blue light in our environments.
At night, a small amount of blue light supports seeing colors correctly and distinct from one another. This important for public safety as well as for the benefit of law enforcement. But, again, the blue light content of outdoor lighting should be kept low to avoid disadvantaging older drivers. It will also benefit nocturnal wildlife and improve our views of the stars.
The solution is to give careful consideration to the spectrum of light and ask tough questions about whether blue is really necessary. If we don't need it, we shouldn't use it. In some cases, it makes the most sense to use light sources such as amber LED that emit very little blue light. In other instances, lighting isn't necessary in the first place. Alternatives such as reflective tape or self-luminous paint can help with wayfinding and mark the presence of obstacles.
Lastly, keep in mind that the potential harm associated with lighting is a function of many variables, not color alone. We should give equal consideration to the duration of lighting as well as its intensity. Choose dimmer lamps when possible, and match light levels to needs. Timers and motion-sensing switches can effectively reduce blue light emission by simply limiting the time that lighting is switched on.
With some mindful thinking about outdoor lighting, we too can cast our blues aside. Contact us today to find out how we can help.