Light pollution - does anyone care?

Twinkling city lights make fantastic postcards, but they are spoiling a much greater spectacle: the night sky.

If all you see when you look to the heavens on a clear night is a handful of stars on a murky orange backdrop, then you have light pollution to blame. It affects 90% of the global population, but puzzlingly a much smaller percentage of us seem to actually care about it.

‘If the daytime sky turned orange you’d be concerned wouldn’t you?’ asks James Abbott, a district councillor in Essex and member of the Campaign for Dark Skies.

There’s no shortage of arguments in favour of saving dark skies. Stargazing inspired ancient cultures from Aborigines to Ancient Greeks, so losing starry nights means forgoing what is essentially a piece of global cultural heritage.

Moreover, twenty four hour light has been shown by numerous studies to disturb birds, insects and nocturnal animals such as bats. Powering unnecessary lights also adds to our planet’s greatest environmental worry: climate change.

For the past decade it’s been hammered into us that we should switch unnecessary lights off at home, yet outdoors it’s a different story. ‘It’s a crazy dichotomy,’ says Abbott. ‘Lighting up the sky doesn’t make any sense at all – it’s a complete waste of energy.’

Many of light pollution’s strongest opponents are of course astronomers. Increasingly, professional astronomers now jet off to observatories in far flung locations where the sky is still relatively unspoiled. Amateurs meanwhile simply have to make do with what they have at home.

Looking on the bright side

Frustratingly, unlike many environmental problems, this one is relatively simple to tackle. ‘Light pollution can be solved at the flick of a switch,’ says Abbott.

According to him, simple measures such as turning off superfluous streetlights in the small hours, or installing motion-activated lighting would greatly reduce the problem. ‘One of my bugbears is floodlit public buildings late at night,’ he adds. The real issue is convincing people that something needs to be done. So why are we complacent?

It’s a rarity nowadays to spend any significant time outdoors at night. It takes the human eye several minutes to fully adapt to the dark and see the stars, and few people experience this in their day to day lives. ‘I do outdoor astronomy lectures, and people are just amazed at how much more they can see after an hour in the dark,’ says Abbott.

It could also be that our positive perceptions of light mean that we struggle to see it as pollution. Unlike many other environmental problems, light pollution isn’t ‘dirty’. It doesn’t choke cities in smog, spew chemicals into rivers or coat seabirds in black gunk, perhaps failing to provoke a gut reaction.

Scared of the dark?

Our disinterest in light pollution could however be hiding a more deep-seated problem: our fear of the dark. Many people believe bright lighting is key to reducing crime and road accidents, yet there is no solid evidence to back this up. ‘If putting lights in was the solution to all problems, then there shouldn’t be any crime or road accidents in the UK, because we are one of the most lit countries in Europe,’ adds Abbott.

Whilst lighting undeniably makes people feel safer, the relationship between light and crime is far more complex. ‘Outside city centres, your chances of being affected by crime are higher in the daytime than they are at night’, says Abbott.

Security lights can dazzle passers by, giving criminals or vandals the chance to go unnoticed. And when a dispute with an electricity firm led to streetlights being switched off for several months in the Swedish town of Övertorneå, the number of thefts and burglaries halved.

Studies into road safety also challenge the true effectiveness of lighting. The UK’s Highways Agency recently found that lighting motorways at night reduced accidents by only 10%, and that installing other safety features such as reflective lane markers could often have a greater impact. As a result, it has begun switching off lights after midnight in safer sections of certain motorways.

Abbott believes these kind of evidence-based policies are exactly what is needed. ‘We’ve got to use the best available technology and actually tackle this from a logical perspective,’ he says.  Whilst some lights, for example in city centres, are obviously needed, it’s not too late to turn back the clock and claim our skies back.

Whilst we can’t expect to return jet black skies everywhere, there is definitely plenty of room for improvement. Despite what mobile phone networks might tell you, the future doesn’t need to be bright or orange.

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