Why Dark Skies are Important
Over 90% of the UK population live under a severely light polluted sky (British Astronomical Association survey) and matters are getting progressively worse. Between 1993 and 2000 light pollution increased by 24%, the amount of truly dark night sky fell from 15% to 11% (CPRE Night Blight initiative).
This degradation of the quality of the night sky is apparent even in Wales. The satellite pictures below show the encroachment of light pollution from the south into the southern edges of the Brecon Beacons National Park.
If you pollute the environment by fly tipping, littering, inappropriately disposing of industrial waste, blasting your neighbours with your hi-fi, you are acting illegally. Not so with light pollution. The Clean Neighbourhoods and Environment Act 2005 gives local authorities powers to address intrusive light nuisance. However the night sky itself, half of our visual environment, has no protection in law.
Why does it matter if you can’t see the stars – we don’t all want to be Patrick Moore!
In addition to denying most of us access to the glory of the night sky, poorly directed and excessive lighting has many other adverse effects – economically, environmentally and medically.
Wasted light costs us money
The economic cost of wasted light has been estimated by the Campaign for Dark Skies as £120 Million a year in the UK due to inefficient street lighting alone and with a total annual cost, including domestic and commercial lighting, approaching £1 Billion. The UK’s 7.5 million street lights (mean power 100W) each direct 15% of their light above the horizon (Institute of Lighting Engineers figures). This amounts to about 830,000 tonnes of CO₂ emissions per year due to wasted street light alone! The overall contribution to the national CO₂ emissions due to wasted light from all sources will be many times larger.
Night lights effect wildlife
There is a strong and growing suspicion that the growth of light pollution is a contributing factor in the decline of many species in the UK. Many birds and animals are affected by stray light intruding into their night world, confusing their natural patterns of activity (including migration), deterring them from established foraging areas, and affecting their breeding cycles causing premature breeding (see abstracts from the Ecological Consequences of Artificial Night Light conference).
Night light effects our health
There is also some cause for concern on the effects of long term inappropriate exposure to night light with the result that in 2007 the World Health Organisation formally categorised shift work as a probable carcinogen.
So what can we do about it?
Unlike many other forms of pollution, light pollution is reversible! Lights can be shielded or replaced and wattages can be reduced to an appropriate level. We can all help in this by individual actions.
So what can we do in the Brecon Beacons National Park? Well we can work with local politicians, businesses and the Park Authority to raise awareness and get some sensible steps taken to reverse the increasing trend in the level of light pollution. There has been a positive “Written Statement of Opinion” on light pollution by WAG in July. This was signed by 21 Assembly Members.
In November 2009, the Galloway Forest Park in Scotland has gained Dark Sky Park status. This is a very prestigious award from the International Dark-Sky Association, and makes Galloway the first park in Europe to achieve this status. Since then Sark, Exmoor, Northumberland, Snowdonia and others have also gained important accreditations and are carrying out many positive works to improve the quality of the night sky and help people enjoy this special aspect of the environment.