Cities need to embrace dark night skies
Brightness harms people’s and other creatures’ health, disrupts ecosystems and changes climate
As the coronavirus pandemic has moved around the world, cities have gone into lockdown and people have been encouraged to stay at home. In many places, curfews have been introduced.
Under the first lockdown in the United Kingdom, I went on numerous night walks in my home city of Manchester. I was struck by several things. Without traffic or trains, birdsong prevailed in this peculiar quietness. The air was fresh and crisp without the usual pollution. Yet the artificial lights of the city at night still blazed, for no one.
As England enters a second lockdown, urban night landscapes remain just as bright. It’s a similar situation around the globe, a powerful reminder of the wasteful ways we have become so accustomed to that we don’t even think about them.
Light pollution is a big problem, not just because of the needless energy and money that it represents. It harms ecosystems and people’s health. Light is everywhere, an oftenuninvited byproduct of our contemporary lives, shining from the devices we use and through the environments we inhabit.
Darkness appears unwanted. How did we get to the point where if an urban night landscape is not dazzling it must be troubling?
From dark to light
Since the Enlightenment, Western culture has been closely bound with ideas of illumination and darkness as representative of good and evil. Shining a light on all things meant the pursuit of truth, purity, knowledge and wisdom. Darkness, by contrast, was associated with ignorance, deviancy, malevolence and barbarism.
Between the 16th and 18th centuries in Europe, for example, changes in attitudes and beliefs toward the night were important in framing perceptions of darkness that have endured. Transformations in societies gave rise to new opportunities for labour and leisure — which, coupled with the evolution of artificial illumination and street lighting, recast the night as an expansion of the day. Rather than being embraced, darkness was viewed as something to be banished with light.
But this view was not necessarily shared by other cultures. For example, in his 1933 classic In Praise of Shadows, the Japanese author Jun’ichir Tanizaki pointed out the absurdity of greater and greater quantities of light. Instead, he celebrated the delicate and nuanced aspects of everyday life that were rapidly being lost as artificial illumination took over:
“The progressive Westerner is determined always to better his lot. From candle to oil lamp, oil lamp to gaslight, gaslight to electric light —
his quest for a brighter light never ceases, he spares no pains to eradicate even the minutest shadow,” he wrote.
In the context of many cities today, darkness is unwanted because it’s associated with criminal, immoral and sinister behaviour. Yet recent research by engineering firm Arup has shown that some of these concerns might be misplaced. Further research has shown that cities need a better understanding of light to help tackle inequality. It can be used to promote civic life and help create urban spaces that are vibrant, accessible and comfortable for the diverse people who share them.
Values of light, clarity, cleanliness and coherence in urban night landscapes have been transferred around the globe, resulting in a worldwide disappearance of the night sky.
The cost of light
This is not a small issue. Scientists are increasingly referring to this as a global problem. The International Dark-sky Association has shown that the waste in both energy and money is huge — in the United States alone this adds up to $3.3-billion and an unnecessary release of 21-million tonnes of carbon dioxide each year.
Of greater concern are the devas
tating effects of over-illumination and light pollution on human health, other species, and the planet’s ecosystems.
The circadian rhythms of humans are disrupted by exposure to artificial light at night, making those working on-call, long hours or in shift work prone to diseases such as cancer, cardiovascular disease, diabetes, obesity and gastrointestinal disorders. Britain’s night workers account for one in nine employees.
Millions of migrating birds become disorientated by electric lights, causing them to crash into buildings, while migrating sea turtles and beetles that use moonlight become disorientated.
It is clear we need alternatives — and quickly. Instead of reducing lighting pollution, new LED technologies increase it. They have been rolled out with an emphasis on economic savings rather than scrutinised and applied with the nuance they are capable of in terms of array, colour, and power.
The emphasis needs to shift from quantity to quality, so that we can appreciate different types of lighting appropriate to different contexts, such as the lighting scheme for Moscow’s Zaryadye Park that reflects existing sources of light.
Valuing darkness
Dark skies have value. They are a profoundly wonderful yet highly threatened natural asset.
We need a new conception of the dark and new visions for places that enable us to reconnect with the night sky through more responsible and less environmentally harmful lighting. Although intended as art, Thierry Cohen’s Villes Éteintes ( Darkened Cities) photographic series is powerful in the way it conveys how future cities could be with a more ecological approach to urban illumination. His photographs are a reminder of our connection to the cosmos and the dark skies many miss out on.
Among the complex and cascading issues that climate change presents, engaging with the potential of darkness in our cities is more important and urgent than ever before. Urban development around the world remains uneven and it would be easy to repeat and increase the problems we have already caused with light pollution. It is time for us to embrace the darkness.