What Is Light Pollution?
Light pollution is excess artificial light that shines where it is neither wanted nor needed. In broad terms, there are three types:
- Sky glow – the pink or orange glow we see for miles around towns and cities, spreading deep into the countryside & blocking our view of the stars, even in an area with no outside lights.
- Glare – the uncomfortable brightness of a light source.
- Light intrusion – light spilling beyond the boundary of the property on which a light is located, sometimes shining through windows and curtains
What’s the problem?
Light Pollution affects our sleeping patterns and melatonin levels, which in turn can affect general or mental health. Light pollution also impacts on wildlife, by interrupting natural rhythms including migration, reproduction and feeding patterns – it can even affect food plants & pollination.
To the south of Herefordshire lies the world’s 5th Dark Sky reserve, in the Brecon Beacons National Park and, with a strong policy on light pollution, Herefordshire itself has the potential to become a haven for dark skies.
5 reasons to love our dark skies
Photo: Matthew Savage
Here are five reasons to get out there, look up at the cosmos, and help us protect our magical starry skies.
1. Peace and tranquillity
Tranquillity is a quality of calm that people experience in places full of the sights and sounds of nature. This sense of calm and wonder takes on an additional quality under dark skies, where we can look up at a whole new world full of stories, science and beauty.
The quiet darkness gives us pause to reflect on our relationship with the countryside and the natural world – and that’s something worth treasuring.
2. Keeping countryside distinct
Darkness at night is one of the key characteristics of the countryside and represents a major difference between what is rural and what is urban. But light doesn’t respect boundaries; it can spread for miles from the source and blurs the distinction between town and country.
3. Allowing wildlife to flourish
The rest of our living world flourishes under cover of darkness, and blurring the line between night and day can have detrimental effects on nature and disrupt natural behaviour.
- Moths are thwarted in their night-time pollination activities by street lighting. Research has shown that swapping old-fashioned street lights for LEDs and turning them off at midnight allows moths to continue their normal pollination, helping re-balance the nocturnal ecosystem.
Brimstone moth attracted to indoor lighting. Photo Barbara Bromhead-Wragg
- Artificial lighting has been linked with trees bursting their buds earlier in the season, a shift with potential knock-on consequences for the whole food web. This shows that while minor changes can make a difference to some wildlife, there is no easy fix for nature, except turning off our lights when we can.
4. Improving human health and wellbeing
The disruption of day-to-night patterns impacts our own physical and mental health. Artificial light, especially when experienced at night, has been shown to decrease our melatonin levels, potentially leading to sleep disorders and increased risk of health problems.
While the draw of our rural landscapes has historically come from their daytime beauty, visiting at night-time is becoming ever more popular as tourists seek out the darkest skies.
For example, the organisation Stargazers Lounge currently chooses Herefordshire for its dark skies to run star parties twice a year & Herefordshire's own Astronomy Society chooses the Madley Environmental Study Centre and Fownhope Recreation Field observation points.
Herefordshire businesses could benefit from ‘astrotourism’ but only if our skies remain dark enough...
Herefordshire Star Count results 2019
64% of those taking part in Herefordshire counted less than 16 stars, with 58% of those managing 10 or less – indicating severe light pollution.
This is a worrying result. In a rural county such as ours, we might expect to count upwards of 25 stars..
These results show an alarming growth in light pollution since the last count in 2016.
Then Herefordshire had the darkest skies, based on average light levels. Light pollution has increased year on year even in this rural county, with more & more people unable to enjoy the night skies. This kind of pollution has an effect on people & wildlife alike.
Herefordshire Council implemented improvements to street lighting in recent years, so where is the light coming from?
Individuals and businesses, whether in an urban or rural environment, should consider the impact of their lighting schemes on the quality of life for others.
What You Can Do?
- Relish the dark and celebrate the inky night- make star gazing in the garden the social occasion of the 21st century!
- Rekindle the spirit of the ARP and the Ministry of Information, and "Put that light out" unless it’s really necessary.
- Think about your outside or security light - Does it need to be on? Could it be positioned better? (e.g. not shining into neighbouring properties).
Domestic / Business security lighting
A profusion of security lights, badly sited or constantly left on, can distract or blind road users and light up neighbours houses and gardens, as well as contributing unnecessarily to CO 2 emissions & household or business expenses.
CPRE worked with Government and others to produce a leaflet about how to use domestic security lighting correctly. It gives helpful tips for your own lighting and neighbours with poorly directed security lights. Read more about this lighting in the 'How to' guide on taking action where lighting causes a statutory nuisance.
Lighting and the law
In 2010, CPRE and the British Astronomical Association's Commission for Dark Skies ran a survey to find out how people's lives are affected by light pollution. Almost 1,400 people took part and the survey revealed that the main causes of light nuisance are road lighting (89%), domestic security lighting (79%), street lights that are more than five years old (77%), businesses (56%), sports grounds (53%) and supermarkets (41%). Almost two-thirds of the light pollution came from a source with an established lighting scheme (65%) such as a development that has been in place for some time. A total 82% of respondents said that the offending lights were left on all night.
In many cases there is something that can be done. The first UK law tackling light pollution came into force in 2006 under Section 102 of the Clean Neighbourhoods and Environment Act (2005). Exterior lighting joins noise and smells on the list of things that can be treated as a Statutory Nuisance; things your local council's Environmental Health Department can take legal action against. The law makes 'exterior light emitted from premises so as to be prejudicial to health or a nuisance' a criminal offence.
This law doesn't tackle all forms of light pollution, only incidents of particularly bad lighting from some types of premises which cause people real nuisance. But CPRE would like to see it used, to raise awareness of the issue and to help people who really are suffering from severe light pollution.
All of CPRE’s work on light pollution can be found on our NightBlight website.