From The Telegraph
London, UK
7 October, 2019
When were you truly in the dark? How light pollution is affecting your body
The hour is approaching midnight, but my bedroom is not properly dark. A horizontal slither of dim yellow light spills over the tops of the curtains. Even with my eyes shut, I still see it. The window overlooks suburban back gardens that are bathed throughout the night in the warm, electric glow of the streetlamps. Several neighbouring houses are still partially lit by bulbs that will stay on until morning. They are keeping the darkness at bay.
Ten miles to the south, the twinkling red, amber and white lights of Canary Wharf glisten like distant jewels in the night sky. There’s a glow of light over the city.
Like many people, I have always found comfort and cosiness in artificial light, particularly at this time of year. But when was the last time I saw the night sky in all its glorious, unpolluted darkness? In Italy, in the summer, high up in the Ligurian hills, we gazed at a tapestry of stars above our rented holiday house, scattered across an unadulterated expanse of black.
There’s a magic in that, which the writer Sigri Sandberg captures beautifully in her book An Ode to Darkness. Already a bestseller in her native Norway and released in the UK this week, it muses lyrically on our intimate relationship with the dark and on “why the ever-encroaching light is damaging our well-being.”
Sandberg travels from her tower block in Oslo to Finse in the north of the country, which, during its dark polar night, is “the best place I know to see the stars,” she writes.
Boarding a train to polar regions to escape the light pollution to which so many of us are constantly exposed sounds romantic, but it’s not an option available to most of us. Even many rural areas now suffer from light pollution as our nights become ever brighter.
A five-year study carried out by the GFZ German Research Centre for Geoscience between 2012 and 2016 found that Earth’s artificially lit outdoor area grew by two per cent a year in that time, along with nighttime brightness. The researchers, who had made satellite observations during consecutive Octobers, said light pollution was in fact even worse than their findings suggested as they did not include some of the LED lighting we’re increasingly using - specifically blue light.
Scientists and environmentalists alike are growing increasingly concerned. Earlier this year, National Geographic reported on how “the excess light we dump into our environments is endangering ecosystems by harming animals whose life cycles depend on dark.” It also warned: “We’re endangering ourselves by altering the biochemical rhythms that normally ebb and flow with natural light levels.”
Some 80% of the world’s population reportedly now lives under light-polluted skies. As Sandberg asks in her prologue, “What is all this artificial light doing to us and everything else that lives? What is it doing to our sleep patterns and rhythms and bodies?”
Corresponding with her over email, I ask what is good about being in total darkness.
“Human beings are...diurnal animals that need both day and night, both light and darkness, both activity and rest,” she says. “Darkness has, since the start, given us this fantastic opportunity to do nothing, and to rest. And darkness, along with silence, is necessary for us.
“The good thing about being in the darkness is the possibility to rest, and also of course the possibility to see the night sky.”
Yet in our permanently switched on age, darkness is increasingly hard to come by. Does Sandberg believe her life has been adversely affected by an excess of artificial light?
“Yes,” she replies. “I’m totally convinced that both me and most of the population on this earth have had an unconsciously unhealthy relationship to artificial light.
“Darkness was, like the cold, an enemy. Humans have fought against it since we lit the first fire. And our nights have become brighter and brighter. Now there is not a very big difference between night and day. And this scares scientists – and it scares me - because it affects our sleep, our rhythms. Some people call sleep disorders a global epidemic.
“Our physical construction and brains are dependent on darkness. Researchers are just at the start of finding out how dangerous too much artificial light really is.”
After setting out to conquer a primeval fear of darkness, the project led her to conclude that “the absence of darkness is in fact much more frightening than darkness itself.” One of the key problems is that melatonin, the hormone that regulates human sleep patterns, is affected by disruptions of the day-night cycle caused by light pollution.
Sleep experts agree it’s a worrying change that does indeed have an impact on sleep, and in turn, human health.
“It is [a problem],” says Dr Neil Stanley, who has been involved in sleep research for more than 37 years and runs a sleep consultancy. “Light and dark are key to our circadian rhythm [body clock] and therefore our sleep. As the sun sets we release melatonin and somewhere between one to three hours after that is the time we go to sleep, or we would do. We are exquisitely sensitive to the dark night cycle. The problem is we now have the ability to have artificial light that can allow us to conquer the night.”
This happens both outside and inside the home. Streetlamps combine with electric lightbulbs, LED displays, the standby lights on our televisions and the melatonin-suppressing blue light emitted by the smartphones we now commonly take into our bedrooms.
“People who are using screens before bedtime will take longer to get to sleep, not sleep as well and feel more sleepy the next day,” says Dr Stanley. “The advice for a bedroom is it needs to be dark, and by dark we mean pitch black.”
Poor sleep has been linked to everything from lower productivity and more days lost to sickness, to obesity, impaired memory and worse mental health.
“People say we have a sleepiness epidemic, but we do it to ourselves,” Dr Stanley adds. “We are paying the price.”
According to a survey by the Campaign to Protect Rural England (CPRE) published earlier this year, just one in 50 of us in this country experiences nights free from light pollution.
“It’s part of our heritage, a connection to the night sky,” says Emma Marrington, a dark skies campaigner at CPRE. “It’s only since the 1950s or 1960s that we’ve had a problem with artificial light. Before that, we had [that] connection.”
Many children are now growing up without ever seeing the night in full darkness; never seeing the sky full of stars. “There’s a lot of concern about the impact on people’s health,” adds Marrington. “Years ago we did a survey asking people how their lives were affected by light pollution. Some said they had changed bedrooms or moved house to get away from it.”
Both seem like drastic solutions. I ask Sandberg what else can be done.
“A lot of things,” she says. “Both in your own home, and also by talking to the authorities and your neighbourhood about the outdoor lightning.
“At home you could take the evening and the night seriously. You could use the curtains to not be disturbed by the outdoor light. Turn out/down your main light, switch off your screens at least one hour before you go to bed. Turn off your phone at night.”
Dr Stanley suggests sticking gaffer tape over the light on your television, swapping curtains for black-out blinds, wearing an eye mask when sleeping, and cutting out screen use for 40 minutes before bedtime. (Others recommend we do so two hours before bedtime.)
Authorities are waking up to the problem, too. One night at the end of last month, Geneva turned off all its lights to raise awareness of light pollution. In March, 188 countries and territories took part in the annual Earth Hour, by switching off their lights in an expression of concern for the planet. The process serves to emphasise just how much we are lighting up our lands every night, and the fact this is not without consequence.
The UK Government already advises local authorities to ensure planning policies and decisions “limit the impact of light pollution from artificial light on local amenity, intrinsically dark landscapes and nature conservation”.
But, says Marrington, “you’ll have a very varied approach between local authorities, with some that are more proactive in enhancing and protecting dark skies...The power to make change happen is at local council level.”
Sandberg’s hope, meanwhile, is that at a personal level we above all open our eyes to natural darkness. “One researcher I have been talking to said, ‘Imagine what it would be like if everyone thought a bit more about, and was a bit more conscious of, their exposure to darkness and light. If that were the case, I think we could save a lot of resources and mitigate a lot of suffering.’”
An Ode To Darkness by Sigri Sandberg
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