Light pollution may not be the first type of pollution that springs to mind when we think of negative impact of human activity on the planet – after all, plastic pollution and the effects of global warming are much more widely documented issues. While many of us are already taking steps such as eliminating single use plastic from our daily lives and changing our diets to include more plant-based foods, we also need to consider how the way we use light in our daily lives can have an impact on the environment.
Unfortunately, light pollution can be a matter of life and death, and so we need to take action if we are to avoid the potentially disastrous effects that can occur. As we become more conscious of the issue, in theory, light pollution is a much simpler problem to tackle than global warming – so let’s take a look at what the issue really is, how insects are impacted, and how we can prevent the issue getting worse.
What is light pollution?
Our modern lifestyles demand being able to see what we’re doing at all hours of the day and night, and so we’re creating more light than ever before to facilitate this. That light pollution is pretty much what it sounds like – excessive artificial light that is made by humans, that has a detrimental effect on the area around it.
While all light has the potential to be considered light pollution, scientists categorise light pollution into a few main types:
Glare is unshielded light that can be hazardous, particularly when driving. It can cause a loss of contrast, can dazzle, and cause temporary loss of vision.
Over-illumination is the excessive use of light. This is typically observed where timers and infrared sensors are not used, improper design or the incorrect use of lighting fixtures, or the wrong type of bulbs are in place. However, this type of light pollution is also seen in areas where ‘daylight lighting’ is demanded by people, or business owners, to reduce crime and to reassure locals that the area is safe – which reassures customers and encourages them to visit the store into the night.
Light trespass is where light creeps into spaces that it shouldn’t be – a good example is that of street lights shining into bedroom windows, but is observed where light goes up into the sky and obstructs the view of the natural night sky.
Skyglow can be observed when looking into the sky above populated areas, and occurs as a result of reflected light, and upward-directed, unshielded and unused light that escapes into the sky.
Light clutter is where there are excessive groupings of lights, such as where there are towns and cities close together, or on a smaller scale, where street lights and brightly lit roadside advertisements clash. Light clutter isn’t just a hazard for wildlife though – it can cause accidents, particularly where they are intended to divert the attention of drivers.
Satellites and planes are another cause of light pollution. Whereas moving lights in the night sky were once only shooting stars, there are now hundreds, if not thousands of lights in the night sky that should not be there, and thus are considered light pollution.
How bad is light pollution?
Approximately 80% of the world’s population lives under skyglow, and across the USA and Europe, around 99% of the human population are unable to experience a completely natural sky from their home. This has been the norm for a long time – in 1994, an earthquake in Los Angeles caused a city-wide power cut. As residents went outside to see what had happened, many of them reported a strange cloud in the sky above them – which turned out to simply be the Milky Way. For humans, the immediate issue with that is that we can’t see the beauty above us – but it is much bigger than that.
In particularly brightly lit cities across the world such as Las Vegas, artificial light pollution that is experienced directly overhead can be observed over 40 miles away. Scientists estimate that light pollution has increased by around 2% each year, which doesn’t sound like a huge amount, but that quickly adds up to a much bigger number as time goes on.
What effects does light pollution have?
Considering that it isn’t natural for the planet to be lit up through the night time hours, it stands to reason that all forms of life on land would be impacted by our artificial light. Any type of pollution is not good for our environment, but light pollution is a huge cause for concern for all species – and particularly when it comes to insects.
Light at night has serious health implications for humans
Our industrialised lifestyles require us to use light throughout the night time hours, but there is significant evidence to suggest that excessive use of light has a damaging impact on human health, contributing to sleep disorders and depression. There are even links with more serious illnesses such as obesity and cancer, although the exact links are yet unclear and demand more research.
Doctors are reporting more patients with insomnia than ever before – around 33% of adult patients report it. While light pollution may not be directly causing insomnia in each and every patient, it isn’t surprising that searches for terms like #insomnia and #cantsleep are increasing across social media channels, while searching for ‘insomnia treatment’ returns more than 69 million results on Google.
The different colours of the light spectrum are essential to understanding why our bodies are impacted so much by light pollution, and why the effects are increasing. Red and orange toned lights are more relaxing for the body, and typically throughout the UK, orange street lamps have been used – primarily because they are the cheapest to run. These are less intrusive for our sleep patterns too. However, since technology has evolved and cheaper to run, brighter LED lights available, many homes and cities are making the switch – but although they’re brighter, safer for driving and cheaper to run, they are generally problematic for our health.
That’s because the super-bright LEDs that are often used tend to be on the bright white, and blue-tinted end of the light spectrum. And, as anyone who has experienced difficulties sleeping after using their phone or laptop too long in the evening can tell you, that isn’t good. Blue light mimics natural daylight, and since our brains can’t distinguish between natural daylight and artificially created blue light, it has the effect of keeping us awake, since our brain receives the blue light as daytime.
Energy wastage impacts upon the planet
In addition to blocking out the night sky, there’s an excessive amount of power wasted when inefficient artificial light is used unnecessarily. That alone should be a good reason to minimise the number of lights that we use wherever possible.
The impact of street lighting on the environment can be minimised simply by switching to LED lighting. When Los Angeles replaced 150,000 streetlights with LEDs, they saved 60% on energy costs – which added up to around $8 million every single year. But – of course – that isn’t the only issue that excess lighting can cause, otherwise we wouldn’t be writing this post.
Scientists believe that dimmer, warmer, and shielded LEDs could be the answer for both reducing pollution and decreasing lighting pollution – but we need to use them carefully.
Careless overuse of cool white, or blue toned LEDs will be even more problematic. In many areas, there is already an over-reliance on lighting up areas unnecessarily, and since LEDs are cheaper to run, there’s a risk that lights everywhere may become the norm. The more unnecessary lights that are put in place, the more insects and other animals are impacted by them, so no matter how much energy that is saved, it won’t stop the potentially disastrous effects on wildlife.
Light pollution has a huge impact on insects
We’re almost all familiar with seeing moths and other insects circling around lights, and mistaking it for the moon. Some of us might have even laughed, or thought that they are just stupid insects – but unfortunately, it is a serious issue. It doesn’t seem like much, but it is estimated that around a third of insects that get trapped in this cycle die from exhaustion, or by being eaten before the morning.
This is just the first of many issues that makes light pollution so problematic for insects, and different species experience different problems – here are a few more specific examples.
- Many insects can have their sense of direction confused by light pollution
- Car headlights draw insects towards them, killing billions every year
- Insects that need to hide from the cold, or catch night pollination, may miss the cues that they would normally get from sunset
- Warning colours of predator insects can be obscured, leading to over- or under- feeding
- Fireflies use bioluminescent cues to find their mates – artificial light interferes with this, leading to lower numbers
- Mayflies can be confused by light reflecting off tarmac and mistake it for water – and proceed to lay their eggs in the road instead of in a lake or river, which can decimate entire populations
- Dung beetles are unable to navigate safely using the light from stars if they can’t see it because of skyglow
- Corn earworm moths stop mating when lighting levels exceed that of a quarter moon at night
- Artificial light can change the time that fruit flies hatch
Many species of insects are thought of as pests, particularly in agriculture where they feed on crops. Light has been used by farmers for many years as a weapon to intentionally suppress insect populations without needing to use damaging chemicals. And while that might be understandable where profits are impacted for small local farms, it becomes a huge issue when it becomes standard practice across the world.
But if insects are truly pests, why should we care that their numbers are declining? Unfortunately, almost every type of insect is essential for the ecosystem, since many are involved in breaking down faeces and returning the nutrients from waste to the earth, as well as being essential for pollinating plants and crops. Even losing even the insects that we hate – such as mosquitos and cockroaches – would mean that other animals wouldn’t be able to eat, so losing the bugs we don’t like would lead to extinction of species that we actually want.
These are just some of the problems that insects are likely to encounter – and unfortunately, we simply don’t know how many more issues insects may face at night as a result of light pollution. Many ecologists and entomologists prefer studying activity during the day, and so until research is carried out during the hours of darkness, we won’t know anywhere close to the full extent of how insect populations are suffering.
It isn’t just insects that are impacted by light pollution though – many birds are disoriented, or lured in by artificial lights and end up smashing into buildings. This issue is a much bigger problem during migrating season, and there are hundreds of other types of animals that find light pollution problematic, including bats, insects, primates, and even plants. It isn’t just plants and animals on land that feel the effects though – fish, turtles, and marine invertebrates including corals are impacted by excess light pollution – and so, in addition to tackling other types of pollution, we need to deal with it.
How can we reduce light pollution?
The good news is that light pollution is perhaps the easiest environmental threat to deal with – since in many cases, all that needs to happen is for the lights to be turned off, or to use them more thoughtfully.
Only use lights when they are necessary. This is an obvious thing to say, but it really will make a huge difference! Turning lights off when they are not needed, especially outside, will stop insects being impacted. Adding timers to ensure that lights aren’t accidentally on all night, and is an easy way to minimise light pollution. In work settings, lights should be switched off at the close of business.
Use PIR motion detector lights for security. There are many places where lights are essential for safety and security, but in places like gardens where light is required, but isn’t necessary to be on throughout the night, using lights that have motion detectors is the easiest way to cut light pollution. Since many models run on solar power – such as this solar LED outdoor wall light – installing these types of lighting can really lower the impact on the environment dramatically.
Use bulbs that are appropriate for the task. Use bulbs of 500 lumens and less, and avoid using bright white, or cool white LEDs – where possible, look for bulbs of 3000 Kelvins or less. (you can find out more about bulb brightness and warmth in this post) Getting the most efficient bulb, and that provides the right amount of light can also prevent the need for using additional lighting and minimise the use of electricity – which isn’t just better for the environment, it is also better for your electricity bill!
Shielding lights wherever possible. This means directing the area of light so that it is only lighting up the area that needs to be lit, rather than the light travelling further than it needs to. When you are positioning outside lights, be sure to angle them downwards, away from the horizontal. When you’re inside your home, be sure to cover windows with curtains or blinds when indoor lights are switched on. This is even more important when it comes to skylights, since the most damaging paths of light are those that shine upwards.
Use decorative lighting sparingly. Using festoons and fairy lights during celebrations is appropriate – but although they look pretty, use them only when you’re actually using your garden, and be sure to turn them off when you come in for the evening. If you’re intending to use lighting around the garden for decorative purposes, avoid blue-toned lights where possible.
Petition the government and local businesses. We can all take steps in our own homes to minimise the impact of our lighting on our local wildlife, but light pollution is a much bigger issue. There are already plenty of petitions online requesting that the government takes action, but you may be successful by contacting businesses that leave their lights on unnecessarily into the night. Consider requesting that they use a timer to switch lights off earlier, and in addition to pointing out the impact on the local ecosystem, you can note that they’ll be saving on their energy bills – money talks, after all.
Our final thoughts
Clearly, we’re huge fans of lighting here at Lyco – it is the focus of our business, after all. And while light pollution is something we should all be aware of, if we make use of our lighting carefully and considerately, we can continue to enjoy the light we need, when we need it, while minimising the impact on the environment. To discuss more about specific types of lighting solutions that we can offer your home or your business, get in touch.
Charles Barnett Managing Director
Charles started Lyco in 1995 with just 4 enthusiastic employees and has grown it considerably over the past 25 years. Charles is also the Managing Director of Lighting Direct and newly acquired Online Lighting. He now has a team of 50 lighting experts working on growing Lyco Group to be the UK leader in lighting for both businesses and homes. Away from the office he is a keen cyclist and is proud to have cycled 1017 miles from Lands End to John O’Groats to raise money for a new residential centre for adults with multiple learning difficulties.