Light changes everything

 

I’VE always been fascinated by light. Or perhaps, to put it more accurately, by the lack of dark compared to the perpetual electronic daylight most of us now live in and accept as the norm.

It may have been an early interest in astronomy and growing up under big Fenland skies that first prompted this lifelong interest. The stunning wonder of the heavens in a gloriously dark and primitive sky that, in those days, was hardly touched even by artificial satellites.

A decade or so ago I started taking a more professional interest in new types of lighting and its potential impacts on life in general and human health in particular, attending some international lighting conferences and writing about the subject more widely through my work as a freelance journalist.

I had a feeling deep inside that something about our modern forms of light and our more recent headlong dash to LED technology wasn’t quite right - and yet I couldn’t quite put my finger on it.

Of course, I was as keen as anyone to promote better dark skies by removing as much of the unnecessary light pollution as possible that now pervades our life after darkness falls. I was also a keen supporter of the fledgling environmental movement so, like most of us, I quickly bought into the industry-led narrative about LED lighting, its energy-saving properties and how good it would be for our planet.

Was there a downside? On the face of it there didn’t appear to be one and it seemed we were all left with little choice but to purchase vastly more expensive LED technology light bulbs. Okay, so the cost was a bit steep compared to the incandescent bulbs we were all replacing but if we were saving Earth in the process surely that was a price worth paying?

But all along the light sensitive ‘eyes’ in my gut were posting warning signs about the slow but inexorable creep of modern-day LED lighting.

In the past few years they might have darkened the heavens in a few locations though that might be more the result of councils up and down the country switching off lighting to save money.

What we might have saved in energy consumption on an individual light has likely more than been replaced by the massive increase in the quantity of lighting installations of all kinds. In reality, LEDs have led to a pandemic of uncontrolled and excessive lighting inside our homes, on public buildings, on transport and on the roads.

Driving home after dark the other evening, I was momentarily blinded by the dazzling headlights of an oncoming car. At first I thought the driver had mistakenly left his lights ‘on beam’ but then I realised this excessive brightness was a new normal for night-time driving. These were just the ultra-bright LED headlights now installed as de facto standard on every new car.

I fear I am not alone in finding overly bright vehicle headlights an increasing driving and road safety problem - and not always just at night, sometimes in the daytime too.

It seems our lighting designers - whether for street “function”, inside the home or on motor vehicles - have run with the excitement of LED technology merely because it was new and the latest thing.

In the process little thought has gone into its intense luminosity, blue-white colour balance or the fact that LED light is acutely directional, more akin to a laser than a conventional light source with excessive glare, a huge increase in light intensity at the centre and a very sharp cut-off.

The UK is not alone. Populations around the world have readily embraced these new forms of light, often unwittingly and without due process to its effect on our bodies and the environment. If I have learnt one thing whilst studying this issue over recent years it is that light is not just light.

Certainly the more intense blue-white light of lower cost high lumen LEDs is potentially damaging for us whether in the home or outdoors - and, treated without due caution, may actually turn out to be a lot worse than our now rejected traditional forms of incandescent lighting.

In her recently published book (Incandescent, September 2019), journalist Anna Levin throws her own spotlight on the transforming colour and tone of our everyday environments. “Light is changing, dramatically. Our world is getting brighter - but is brighter always better?” she asks.

The thrust of Levin’s book is that natural light (and dark) is fundamental to almost every aspect of life on Earth, interacting with humans and animals in profound yet subtle ways. “We mess with the eternal rhythm of dawn-day-dusk-night at our peril,” says Levin. “But mess with it we have, and we still don't truly understand the consequences.”

She claims that technology and legislation have crushed our previously warm, incandescent lighting in favour of harsher, often glaring alternatives.

And there is the irony. Since regulations were passed introducing legislation banning incandescent lamps, domestic energy consumption has actually risen and so, according to the UK Department for the Environment, there has been no overall saving.

In recent years there can be no question that our night-time world has been rapidly infiltrated by a voracious predator - an un-natural form of light that is both seen and unseen at the same time.

Incandescent is a well-researched and written book, with accessible analysis and explanations supported by technical details about LED lighting’s potential impact on human health and the wider environment. It throws an intriguing new light on an unanticipated problem that is only now becoming recognised.

Some useful links:
Anna Levin - Incandescent
LightAware - charity & support
Soft Lights - lighting with thought 
Clive Simpson - Writer & Editor

Light of the world

Experts from around the globe gathered at Leicester’s De Monfort University in the UK this week to discuss ‘artificial light’ and how it is not only affecting the world we live in but is also increasingly helping define it.

The fact that light at night affects us adversely more than we might think is not something many of us give a second thought to - let alone consider it necessary to be discussed at an international conference.

But those at ALAN 14 - the second ‘Artificial Light at Night’ annual conference - had a significantly different take and highlighted a number of concerns that need to be taken seriously.

The scientists and researchers had travelled from the different parts of the UK, Ireland, the United States, Europe and Australia to present their findings on light-related topics and related research across the fields of health, biology, pollution, ecology, technology and design.

ALAN 2014 examined the use of artificial lighting at night in all its forms, as well as the spectrum of adverse effects that artificial light at - known collectively as light pollution - night may cause.

The theme coming through loud and clear is that society at large is barely beginning to recognising that such liberal and indiscriminate use of illumination is at a mounting cost to both the environment and ourselves.

Interestingly, an increasing number of scientific studies are now seriously questioning the long-held premise that humans are largely immune to the effects of artificial light at night.

Research is now confirming that artificial light - even in quite small doses - disrupts sleep, confuses circadian rhythms and impedes the production of the hormone melatonin.

All of which is bad news if the consequences of excessive exposure to light at night really do include an increased risk for obesity, diabetes, cancer and cardiovascular disease.

Back in 2012 the American Medical Association (AMA) called for more research into the risks and benefits of occupational and environmental exposure to artificial light at night and for the introduction of new lighting technologies at home and at work that minimise circadian disruption.

Technological advances such as LEDs (light-emitting diodes) have improved the potential for better targeted lighting - but for now they are often brighter and more intrusive than the old lights they are replacing.

Much of our modern light - whether from TVs, computer screens, smart phones and electronic gadgets or from outdoor lighting of one form or another - is also ‘blue’ rich and so proves even more disruptive to the 24 hour biological process that regulates the body's functions.

According to conference organiser Prof Martin Morgan-Taylor, of the School of Law, De Montfort University, Leicester, and a Legal Advisor to the UK Campaign for Dark Skies, the physiological effects caused by lighting may be similar to noise.

"Admittedly, there are comparatively few studies as yet on the problems caused by lighting, but lights can and do wake people up, just as does noise," he said.

"Moreover, with light it appears that the subject does not need to be fully awakened to suffer the same negative effects as someone who has been deprived of sleep altogether."

This means that people's health can even be adversely affected by ‘security’ floodlighting and, what the Chartered Institute of Environmental Health (CIEH) refers to as, ‘light briefly turning on and off' during the night.

Prof Morgan-Taylor stated the research concerning cancer risks does not restrict itself to lighting that wakes the subject because risk factors are akin to the levels of night-time light entering a bedroom.

Paul Marchant, of Leeds Metropolitan University, questioned the widely held perception of ‘improved’ (brighter) lighting is always beneficial in reducing road accidents and crime.

The generic objection to this - based on the premise that light equals protection and darkness represents danger - is that we need all this light for safety and security, he said.

Such common belief goes a long way to explain why many supermarkets, petrol station forecourts and car parks, as well as our own driveways and yards, are lit more than ten times as brightly as they were just 20 years ago.

"In fact, the issue of light at night and safety is rather more complex, and there is little compelling evidence to support widespread such mis-assumptions," he said.

"Ever-brighter lights can, for example, actually diminish security by casting glare that impedes vision and creates shadows where criminals can hide."

Emma Marrington, CPRE Dark Skies campaigner and author of ‘Shedding Light’, a survey of local authority lighting policies, said some local authorities are taking steps in the right direction.

She said the research had revealed no evidence to support the fear that adjusting or dimming street lights impacted on public safety.

"We urge councils to do more to control lighting in their areas and ensure that the right lighting is used only where and when it is needed."

"We're not advocating changes where they're not appropriate - but why shine bright lights on residential streets, quiet roads and open countryside throughout the night when they are not needed?"

The consistent theme emerging from ALAN 14 was that there are many different aspects to artificial light at night and the effects on our well-being, ecology and life in general are only just beginning to be understood.

We will, no doubt, continue to tinker with the natural world and all its variances, and the exponential growth of artificial light in our homes and across the planet shows now time of dimming yet.

In the meantime, conferences like ALAN will gradually produce evidence in an attempt to redress the balance.

And one day there may come a time of new enlightenment - when we release that at certain times of the day we need dark more than light.


The conference was hosted by Leicester De Montfort Law School, De Montfort University, and co-organised with the EU COST Action LoNNe (Loss of the Night Network) in association with the International Dark Sky Association. My thanks to Martin Morgan-Taylor and Katie Scott.

LED lighting's dark side

New LED street lighting being installed by councils throughout the country to save money and cut carbon emissions could mean more sleepless nights and ultimately be bad for our health.

A study by the Campaign for the Protection of Rural England (CPRE) says some eco-friendly low-energy LED (light emitting diode) street lighting creates unnecessary glare and might have serious effects on people’s well-being.

Light pollution expert Martin Morgan-Taylor has called for more research into which wavelengths, levels and durations of lighting pose health threats - and how this compares with modern lighting practices.

The lecturer - from Leicester’s De Montfort University - says medical research is increasingly linking LED lighting with more serious health issues such as cancer and depression.

"Artificial lighting is known to have negative effects on human health and well-being if sleep is disrupted by bright light shining into bedroom windows," he said.

"What we know is that ‘white’ or ‘blue-rich’ lighting - which mimics natural daylight - is being increasingly used at night.

"This type of light suppresses the production of a circadian rhythm hormone called melatonin, which is believed to be a powerful anti-oxidant that helps to ward off some cancers," he said.

The CPRE report, ‘Shedding Light – a survey of local authority approaches to lighting in England’ is the first piece of research to ask councils how they control light pollution.

Councils are urged to give ‘careful consideration’ to the type of LED lighting they use and weigh the potential impacts that higher temperature blue-rich lighting has on ecology and human health.

The report says authorities across England could be doing more to reduce the impact of light pollution and be saving hundreds of thousands of pounds a year in the process by using dimming schemes.

It also urges councils to preserve dark skies by having a ‘presumption against’ new lighting in existing dark areas and preventing ‘inappropriate and badly designed development’ that masks views of the night sky.

But according to the survey of 83 local authorities fewer than two thirds of councils in England are actively seeking to minimise the impact of bad lighting - despite recent changes to planning laws which encourage them to do so.

The CPRE also recommends new street lighting should be tested ‘in situ’ before schemes are rolled out across wider areas to ensure that it is the minimum required for the task and does not cause a nuisance to residents.

Street lighting in England costs councils around £616m a year and can account for up to 30% of their carbon emissions.

The CPRE study reveals that despite the number of people living with severe light pollution around the country growing more than a third of councils have no formal policy in place.

Almost half of councils responding said they were involved in dimming street lights in their areas and a third say they are now switching off street lights - typically between midnight and 5am.

The research found dimming schemes are significantly more popular with residents than switch off schemes - with 68 per cent of respondents saying local communities had been very supportive.

Some council schemes to replace old-style sodium ‘orange’ street lighting with new LED lamps have attracted criticism from nearby residents.

Last month people in a west London borough complained that new LED street lamps were so bright they were no longer getting a good night's sleep.

Hounslow council started using the lights as part of a multi-million pound improvement scheme but people living close to the new LED lighting described it is ‘like living on a floodlit soccer pitch’.

Elsewhere, Leicester city council is updating 32,000 of its 37,000 street lights as part of a commitment to reduce the council's carbon footprint by 50% before 2025.

The three year £13.9m project began in March 2013 and will contribute an estimated saving of 5,350 tonnes of carbon emissions per annum.

It includes a Central Management System (CMS) for remote control of lighting levels in specific areas, allowing dimmed lighting, for example, in the early hours before dawn.

The council says replacing its existing stock with LED lighting will reduce energy usage and carbon emissions by over 40% compared with current levels, saving electricity charges (at 2013 prices) of £0.84m a year.

Using a CMS should provide a further 17% reduction, increasing the overall savings to 57% of current energy usage and carbon emissions, and slashing a total of £1.2m off its annual electricity bill.


Aerial view of Leicester city centre at night clearly showing the streets
where new white LED lighting has already been installed.

Other councils are, however, taking a more cautious route. In Essex, the streets have been equipped with one of the world’s largest wireless street lighting control systems.

Around 125,000 of the county’s street lights have been wirelessly linked, allowing centralised control and fault detection.

The council expects to reduce the energy cost of street lighting by around £1.3 million per year and to cut annual carbon emissions by over 8,000 tons.

Earlier this year Trafford council in Manchester delayed its £9.3m scheme to replace all its 27,000 street lights after a resident threatened High Court action.

Simon Nicholas, a chartered engineer and businessman, raised concerns that new LED lighting had the potential to cause health problems.

"We're breaking new ground here and new evidence is emerging all the time," he said. "The council has not fully taken these studies into account."

Mr Nicholas claimed some councils are not looking at the bigger picture ."LEDs are currently on an exponential curve in terms of development," he said.

"In five years’ time we may well have really good LED street lights. Anyone charging in now is making a huge mistake."

Emma Marrington, CPRE Dark Skies campaigner and author of the ‘Shedding Light’ report, said: "Many local authorities are taking steps in the right direction but much more can be done.

"We urge councils to do more to control lighting in their areas and ensure that the right lighting is used only where and when it is needed."

She said the research had revealed no evidence to support the fear that adjusting or dimming street lights impacted on public safety.

"We're not advocating changes where they're not appropriate - but why shine bright lights on residential streets, quiet roads and open countryside throughout the night when it's not needed?

"Genuine dark starry nights are becoming harder and harder to find which is why councils should take action to control it now. Light pollution blurs the distinction between town and country, ruins the countryside's tranquil character and denies us the experience of a truly starry sky."

The Lighthouse Keeper is written by Clive Simpson - for more information, commission
enquiries or to re-publish any of his articles click here for contact information

Street lite

Photo: Clive Simpson

On the road home the night-time light has changed. We are in the heart of South Lincolnshire’s farming landscape approaching the interestingly named hamlet of Cowbit, midway along the old main road between Crowland and Spalding.

The road bends gently along a raised bank, originally built to stave off flooding from the plain of the nearby River Welland, and the lights cut through the night like harbour beacons around a vast concave seashore.

Tonight, I notice that the familiar curve of orange-glowing street lights - picking out the homeward route ahead against the flat Fenland horizon - have been replaced by the cool and dazzlingly bright light of modern LED technology.

Definitely cheaper to run - and therefore more energy efficient - these lights are an increasing part of our night-time scenery up and down the country.

But after five miles of driving along dark, unlit roads the clinical brilliance comes as a shock to night-adjusted eyes.

All this is part of local authority plans - in this case Lincolnshire County Council - to replace and update all our traditional street and road lighting over the coming years.

Energy and cost savings aside, the new kind of lighting is defined by its brightness and intensity, like spotlights on a West End stage show. But at least there is less apparent spillage into the heavens above.

LED luminance is potentially much more controllable than traditional sodium light and so one might reasonably ask the question of our lighting engineers - is it necessary (and even safe for approaching motorists) to have these beams on full luminance at the point where we suddenly cross from dark to light?

There are increasing complaints from across the country where such shiny new lights - installed in normal streets and cul-de-sacs - have cut through curtained windows to illuminate living and sleeping spaces, playing havoc for those in the vicinity.

Bright is not always best for human health and there is obviously a need for more research into the potential risks from the glare of LED lighting.

Already it is well documented that exposure to LED light suppresses melatonin production by up to five times more than exposure to sodium-based light, disrupting our biological clocks and affecting sleeping and rest periods.

Recent research in Spain has indicated that long-term exposure to LED street lighting could, as a result of the high levels of blue band radiation, cause irreparable harm to the retina of the human eye.

And last year a report by the French government stated that a luminance level higher than 10,000 cd/m2 causes visual discomfort whatever the position of the lighting unit in the field of vision.

As the emission surfaces of LEDs are highly-concentrated point sources the luminance of each individual source can be 1000 times higher than discomfort levels, making this intense glare a tangible problem.

Which brings me to reflect on the familiar orange, phosphorescent glow that has been part of our night time scene for so long.

Despite its intrusion, particularly into the night sky above, will we come to rue the day of its disappearance?

At the ending of DH Lawrence’s ‘Sons and Lovers’ the book’s central character Paul Morel is drawn ‘towards the city's gold phosphorescence’.

Signifying corruption and decay, ‘phosphorescence' was to become one of Lawrence’s jargon words in subsequent novels.

‘But no, he would not give in. Turning sharply, he walked towards the city's gold phosphorescence. His fists were shut, his mouth set fast. He would not take that direction, to the darkness... He walked towards the faintly humming, glowing town, quickly.’

For Paul Morel, the ending was something of a false epiphany. That 'gold phosphorescence' was an emanation of the mechanised life of the industrialised world - the glow of false promise.

In the end Paul’s tragedy was that he was only able to move in the direction of the city, humming not with the natural activity of a hive, but with machinery, and glowing not with sunshine and warmth but with the ghastly phosphorescence of street lamps and decay.

That familiar orange glow in our night-time skies does indeed represent something of the past, industrial age - whereas the clinical, white light of LEDs is symbolic of the modern, sanitised world.

Our continued attempts to tame and banish the natural darkness and rhythms of life only serve to deepen the shadows around us. What, I wonder, would Lawrence have made of this?

The Lighthouse Keeper is written by Clive Simpson - for more information, commission enquiries or to re-publish any of his articles click here for contact information

Always look on the bright side

The headlines this week have all been about how Britain will keep the lights on in the midst of the government’s failure on long term energy policy and blatant profiteering by the country’s big six energy suppliers.

But this evening an estimated 10 million people in Britain will turn their lights off voluntarily as part of Earth Hour, a symbolic gesture to show support for environmental issues.

Now in its eighth year, the mass participation world-wide event comes as the Intergovernmental Panel on Climate Change (IPCC) prepares to launch its latest report in Japan on Monday, outlining how climate change will affect wildlife, food supplies, water and the weather.

"It's fortuitous timing that as millions of people around the world take part in WWF's Earth Hour, the world's leading scientists release the latest IPCC report, which highlights the various impacts of climate change," said Colin Butfield, director of public engagement and campaigns at WWF-UK.

"The significance of these two events is massive. Climate change is the biggest environmental threat facing our planet – it's real, it's happening right now, and we need to act fast."

Among the world's famous landmarks that will dim their lights are the Empire State building in New York, the Brandenburg Gate in Berlin, the Eiffel Tower in Paris, the Kremlin and Red Square in Moscow, the Bosphorus Bridge in Turkey and the Burj Khalifa in Dubai

In the UK, the Houses of Parliament, Buckingham Palace, Tower Bridge and the London Eye will all dim their lights, with an estimated 10 million Britons expected to take part.

Launched in Australia in 2007, WWF says Earth Hour has now grown to become the world's biggest environmental event, mobilising people around a range of issues from deforestation to energy efficiency. Last year saw more than 7,000 towns and cities in 154 countries take part.

A survey commissioned by WWF-UK this week found that almost half (47%) of respondents said they would be willing to switch their political allegiance to a different party based on the strength of environmental policies, with 73% saying the leaders of the UK's main political parties are not currently giving enough emphasis to the environment.


Tonight from 08.25 pm the WWF website will be live-streaming highlights of Earth Hour, from the spectacular London and global landmark switch offs to a special performance from Sophie Ellis Bextor - http://earthhour.wwf.org.uk/tune-in-to-our-livestream-this-Saturday

For further illuminating reading see - The end of night and Fear of the dark

The End of Night

The bright lights of Europe spilling into the night as seen from the Space Station.

Night is no longer as dark as it used to be. Street lamps, neon signs, ‘security' lights and the rest all contribute to an ever-present glow that has transformed the natural world and turned modern life into a wash of artificial light.

It is a theme the Lighthouse Keeper has looked at in several blog essays this autumn, partly inspired by one of this summer's best-selling books ‘The End of Night', written by US-based journalist Paul Bogard.

Light pollution around the world has expanded exponentially in recent decades and now it is reckoned that the vast majority people across Western Europe and the United States no longer experience a truly dark night.

Night's natural darkness is invaluable for our spiritual health and the health of the natural world and as a consequence every living creature, including ourselves, suffers from its loss.

Like the advancement of technology it is one of those things that changes subtly against the backdrop of busy lives – and almost without noticing we become accustomed to a new ‘normal'.
 

The Bortle scale, which classifies the darkness of skies from point of view of an astronomer, 
was originally published in Sky & Telescope magazine in 2001 and is an apt illustration for Bogard’s theme.

 
In his book, Bogard investigates the meaning of darkness and travels to some of the world's intensely lit cities - from Paris, the ‘city of light' to glittering Las Vegas and to still gas-lit streets of London's Westminster district, meeting an inimitable range of characters along the way.

Bogard contrasts the skies above our cities and urban populations to some of the most remote and darkest places on the globe, like the great national parks in America and the Island of Sark off the British coast.

He discusses how light is negatively affecting the natural world, how our well-being is significantly influenced by darkness or its lack, and how it's not a matter of using light at night or not, but rather when and where, how and how much.

Travelling the world looking for dark skies, Bogard considers our affinity for artificial light, the false sense of security it provides, and its implications.

He covers such broadly diverse issues as the health impacts of working the night-shift to the persecution of bats, and urges the reader to weigh the ramifications of light pollution and our failure to address them.  

The growth of light piollution across the United States, including
a projection for the year 2025.

 
"We think that because of television, the internet, or jet travel we see a lot of the planet," says Bogard.

"But the only chance we really have to retain our sense of the scale in the real universe is by looking at the night sky."

As we approach the winter solstice when the dark nights of the northern hemisphere reach their longest, what better time to delve into such a book?

Bogard's evocation of the night blends environmental and cultural history to make reading about light pollution a surprising pleasure.

By reclaiming the night we stand only to gain. Not least in decreased energy costs and redressing the balance of life but also in that other fast-disappearing phenomenon - wonder.

Bogard draws attention to the naturally dark night as a landscape in its own right - a separate, incredibly valuable environment that we overlook and destroy at our own peril.

‘The End of Night’ by Paul Bogard
is published by Fourth Estate and
is available at your local bookshop
or from Amazon.

Blinded by the night

Winter sunset over the Solent from Portsdown Hill - Clive Simpson

It is hardly surprising to learn that in our modern, consumer-driven culture we are using far more light during the hours of darkness than we actually need.

But what is not generally recognised in our liberal use of illumination is the mounting cost to both the environment and ourselves.

An increasing number of scientific studies are questioning the long-held premise that humans are largely immune to the effects of artificial light at night.

And our own eyes, if only we opened them long enough in a metaphorical sense to see the bigger picture, would surely agree.

Research indicates that artificial nocturnal light - even in quite small doses - disrupts sleep, confuses circadian rhythms and impedes the production of the hormone melatonin.

All of which is bad news if the consequences of excessive exposure to light at night really do include an increased risk for obesity, diabetes and cardiovascular disease.

Technological advances such as LEDs (light-emitting diodes) have certainly improved the potential for better targeted lighting - but they are often brighter and more intrusive than the old lights they are replacing.

And much more of this modern light - whether from TVs, computer screens and electronic gadgets or from outdoor lighting of one form or another - is rich with blue wavelengths and most disruptive to the 24 hour biological process that regulates the body's functions.

In effect, blue light sends subtle messages to our brain that night is over – or in a basic, primal way that morning's blue sky has returned and that the day has begun - quite the opposite signal we need in the middle of the night.

Two years ago the American Medical Association (AMA) called for increased research into the risks and benefits of occupational and environmental exposure to artificial light at night and for the introduction of new lighting technologies at home and at work that minimise circadian disruption.

According to Prof Martin Morgan Taylor, of the School of Law, De Montfort University, Leicester, and a Legal Advisor (Lighting) to the UK Campaign for Dark Skies, the physiological effects caused by lighting may be similar to noise.

In his paper ‘Light Pollution and Nuisance: The Enforcement Guidance for Light as a Statutory Nuisance' he says: "Admittedly, there are comparatively few studies as yet on the problems caused by lighting, but lights can and do wake people up, as does noise.

"Moreover, with noise it appears that the subject does not need to be fully awakened to suffer the same negative effects as someone who has been deprived of sleep altogether."

As a result, people's health could be adversely affected by the floodlighting and what the Chartered Institute of Environmental Health (CIEH) refers to as ‘light briefly turning on and off' during the night.

Prof Morgan Taylor states the research concerning cancer risks does not restrict itself to lighting that wakes the subject but the risk factor is akin to the level of night-time light entering the bedroom.

"The glare from overly bright lighting can also cause further problems, for although the iris may contract to cut down the amount of light entering the eye, the scale of the glare from floodlighting can cause momentary blindness and pain," he says. "This is particularly an issue for the elderly, as the muscles controlling the iris do tend to become less efficient with age."

On a personal level, while we seldom leave our interior lights bare, most of our outdoor lighting remains unshielded – indiscriminately sending light straight into the sky, into our eyes, and into our neighbours' bedrooms.

The relatively simple act of adjusting or shielding outdoor lights by installing or retrofitting lamp fixtures that direct light downward to its intended target represents our best chance to control light pollution.

The generic objection to this - based on the premise that light equals protection and darkness represents danger - is that we need all this light for safety and security.

This common belief goes a long way to explain why many supermarkets, petrol station forecourts and car parks as well as our own driveways and yards are lit more than ten times as brightly as they were just 20 years ago.

In fact, the issue of light at night and safety is rather more complex, with little compelling evidence to support widespread assumptions.

For example, ever-brighter lights can actually diminish security by casting glare that impedes vision and creates shadows where criminals can hide.

The ‘World Atlas of the Artificial Night Sky Brightness', a series of computer-generated maps from satellite data that depict the extent of light pollution across the globe, were created by Italian astronomer Fabio Falchi and illustrate the point nicely.

Today, or to be correct, tonight, we have levels of light hundreds and thousands of times higher than the natural night time level – and light pollution is currently rising by an average of 20 per cent a year.

So this evening, before you flood the yard or your front drive with brilliant light, consider for a moment the opposite side of the day. Would we tolerate, with the same kind of indifference, attempts to modify the daytime by lowering light levels a hundred or a thousand times?

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If you enjoyed this Lighthouse Keeper essay by Clive Simpson looking at the impact of artificial light at night in our modern world please recommend or Tweet the link - Blinded by the night. The title is derived from ‘Blinded by the Light', a song written and originally recorded by Bruce Springsteen and widely known through the 1976 chart-topping version recorded by Manfred Mann's Earth Band.

Let there be light

The Milky Way strode across the sky, a band of faint light spanning almost from horizon to horizon. In the distance, lights sparkled like ships on a dark ocean. Such a dark sky with a myriad twinkling stars is a sight that is becoming all too rare - or even beyond the experience of many.

This is the heart of the Fens at night. A natural planetarium with glorious low horizons in every direction and a pitch dark sky, just far enough from the sodium city lights of Peterborough and the market towns of Stamford and Spalding.

Indeed, this part of South Lincolnshire, an industrial farming and food-producing landscape by day, is by night one of Britain’s dwindling exceptions to our light-polluted lives.

According to the Council for the Protection of Rural England (CPRE), places with the ‘purest’ night-time darkness are (perhaps by definition) among the least populated in the country.

Dartmoor, Exmoor and the Quantock Hills in the south west; Salisbury Plain and the top of the Chilterns in southern England; parts of Lincolnshire to the east; the Black Mountains and the Brecons in Wales; the Yorkshire moors and some of Northumberland; plus large swathes of Scotland, outside major cities and the Borders.

Early this year Sark – the smallest of the four Channel Islands at just a couple of square miles – became the world's first officially-designated ‘Dark Sky Island’.

The US-based International Dark-Sky Association measured Sark's night-time illumination levels and assessed the degree of visibility of constellations in the night sky. And to assist Sark's claim, one of its government officers visited every outside light on the island and recommended measures to cut artificial light seeping into the sky.

Sark is not Britain's only dark success. In 2009 Galloway Forest in Scotland was designated Europe's first ‘Dark Sky Park’. As a result visitor numbers are booming, a new observatory is planned for the edge of the forest and neighbouring local councils have introduced restrictions on outside lighting to preserve the quality of darkness.

The Inner Hebrides’ island of Coll, 13 miles long and three miles wide with two main roads and a small airport, is another dark spot with no security lights on homes, or traffic or street lights.

Much closer to home, the Rutland village of Market Overton recently reduced its light pollution by replacing its old sodium street lights with modern light-emitting diode lamps. Its 39 lamps cost over £20,000 in total to convert but immediately produced an 80 per cent saving in electricity.

These locations, however, remain the exceptions to the light-polluted rule. And they are getting rarer thanks to what the Campaign for Dark Skies describes as ‘wasteful’ over-provision of domestic lighting by British householders.

CPRE has, for several years, urged government action to limit light pollution from street lamps, overnight illumination of shopping centres, office blocks and public buildings, stark upward lighting from floodlit sports complexes and, at the household level, outdoor lights that are unnecessarily bright or disperse their illumination. Of course it would also save a lot of money and energy too – Britain's street lamps alone cost an estimated £500 million a year to run.

The most common forms of such pollution are ‘light trespass’ when illumination from Britain's 22 million homes and 7.5 million street lights, even if designed with the intention of shining downwards, typically also extends upwards. You can see it in this picture of the UK at night as seen by astronauts passing overhead aboard the International Space Station.

Two other common forms are ‘sky glow’ – that orange glow visible for tens of miles around towns and cities easily seen from the air or from distant roads – and ‘glare’, the harsh white light on some modern housing estates and golf driving ranges at night.

As October marches onwards, here in the northern hemisphere we are plunging headlong into days of less daylight, longer nights and the clocks going back – all marking the onset of winter. And, while we say we prefer it lighter for longer, in reality most of us only now experience a limited degree of darkness.

Modern electricity's triumph over the night keeps us all busier. We live in a fast-moving, fully lit world where night still happens but is more of an optional experience – a kind of failed daylight. Our 24/7 supermarket culture has done it’s best to phase out the night.

Yet slowness and silence – the different rhythm of the night – are a necessary correction to the day. Life is too short to be all daylight. Moments of life take on a different quality at night-time, where the moon reflects the light of the sun and we have time to reflect what life is to us. So why not turn down the lights and rest awhile? Night is not less – it's more.

 

The Lighthouse Keeper is written by Clive Simpson - for more information, commission enquiries or to re-publish any of his articles click here for contact details