Guardians of the night sky

With the launch of the CPRE’s new interactive dark skies maps, Emma Marrington, one of their senior rural policy campaigners explains the importance of night skies free from light pollution.

How many constellations could you see last time you looked into the night sky? If you live in England, then there’s a good chance you couldn’t see very many. CPRE has discovered this week that just 22% of the country is untouched by light pollution, making the magical experience of gazing up at stars and galaxies an elusive one for most of the population.

But light pollution doesn’t just obscure our view of the night sky. It also harms wildlife by interrupting natural rhythms such as migration, feeding patterns and reproduction. Light pollution represents a huge waste of energy, too: street lights can account for between 15-30% of a council’s carbon emissions.

This week, CPRE has released new interactive maps that give the most detailed ever picture of England’s dark skies and light pollution. Produced using satellite images captured at 1.30 am throughout September 2015, the maps will help to identify problem areas where action is needed to tackle light pollution, and also to find the darkest skies that are in need of protection. We worked with several of England’s National Parks to create detailed maps, showing how light levels vary in each park. Our interactive map also shows the National Parks in Wales and Scotland, although detailed maps were not created for these areas.

Looking at the maps, it is clear that many of the areas where people can best enjoy the stars are in England’s National Parks: they enjoy 59% of England’s pristine dark skies, completely free of light pollution. Given that people are increasingly seeking out spots where they can enjoy that clear view, it’s not surprising that ‘astrotourism’ is providing a year-round attraction for many visitors to National Parks. Several of England’s National Parks are working towards Dark Sky status, awarded by the International Dark Sky Association, and in many respects they are blazing a trail in their efforts to protect dark skies from light pollution.

In 2011, Exmoor National Park became the first International Dark Sky Reserve in Europe. CPRE’s maps show that the park has 92% pristine dark skies, and very little light pollution elsewhere. The park has developed strong lighting policies in its local plan to ensure that its dark skies remain unspoiled.

As well as being home to the first Dark Sky Reserve in Europe, we are also lucky enough to have Europe’s largest area of protected night sky. In 2013, Northumberland National Park and Kielder Water & Forest Park were awarded Dark Sky status and became the ‘Northumberland International Dark Sky Park’, covering an area of 1,483 square kilometres. Our maps not only show that 96% of Northumberland National Park has pristine dark skies, but also that Kielder Forest Park has the very darkest spot in England - a remote hillside on East Kielder Moor.

As National Park Authorities have planning control over their areas, they play a crucial role in protecting our beautiful landscapes and the skies above them. We’d like to see National Parks continue their great work on this issue, by having strong policies in Management Plans and local plans to control light pollution and using the maps to inform planning decisions. The maps will also be strong evidence to support applications for Dark Sky status, which will help provide visitors with a unique experience of dark skies for years to come.

It’s not only National Park Authorities who will find these maps useful, however. Businesses and local authorities can see where money is being wasted by excess lights shining through the night. People can use the maps to identify light pollution in their area that requires action.

And, perhaps most simply, everyone can use the maps to seek out their nearest expanse of dark skies, to take in a clearer view of the breath-taking night sky. Whether it’s in a National Park or on a village green, get out there and enjoy one of nature’s most amazing spectacles! 

You can access the maps via our dedicated website: http://nightblight.cpre.org.uk

CPRE’s report Night Blight: Mapping England’s light pollution and dark skies can be found in the ‘Resources’ section of the above website, along with lesson plans for primary school children and other resources.

First image: Northumberland International Dark Sky Park, Harbottle Castle Milky Way © Ian Glendinning

Second image: North York Moors, Milky Way and Perseid Meteor shower from Sutton Bank © Russ Baker