I happened to see a film the other night, all about light pollution.
We were staying at a campsite in San Pedro de Atacama and the film was being shown in the open air in the town square as part of a local campaign to reduce light pollution. Hardly surprising as the Atacama Desert in northern Chile is one of those parts of the world where it is still possible to see the stars at night.As the film began by demonstrating how in much of the world it is no longer possible to see the stars or even the plants of our solar system in the night sky, I was reminded us having left Las Vegas a year previously, driving maybe 100 miles, and looking back to see the lights of Vegas glowing in an orange dome in the distance. That scene was such a contrast to the nights we have been enthralled to see the stars in the night sky in places far from the city lights.
As I watched the film I reflected on my childhood in England in the 1960’s, when the street lights in our home town would go out at 11.00 pm. Then in the 1980’s that became 2.00 am. Now they stay on all night, often in the guise of ‘security’. As children and young adults we could see the stars in the night sky. Today’s city and town dwelling children hardly know that the stars are there. They have no experience of the wonder of seeing the night sky.
But it’s not just aesthetics, the price of progress: the film went on to describe some more of the effects of a growing obsession with light.
It is believed that migrating birds use the stars to navigate and light pollution in the worst affected areas is affecting their ability to migrate. In some cities, particularly in the US, it is known that birds often crash into the tall buildings, falling injured to the ground, with broken wings and broken beaks. There is a whole army of bird rescuers who go out and pick up and look after as many fallen birds as they can find.
Young turtles have evolved to hatch at night and head towards the brightest horizon as soon as they hatch. As the sea reflects the moon and starlight this means they can head straight to the safety of the sea. However in some places, where electric light pollution is creeping in, the young turtles are often found heading in the wrong direction, towards the wrong light.
On a human level, recent research has indicated a link in the progression of some cancers in humans, particularly breast and prostrate cancers. Melatonin in the body apparently suppresses the growth of cancerous tumours but melatonin levels only rise during periods of darkness. Sleeping in a lit room, whether lit internally or by bright street lights, reduces the body’s production of melatonin. Shift workers, who work by electric light at night and sleep during sunlight hours much of the time are particularly at risk.
In many places street lighting is chosen for its appearance rather than its practicality. Light globes appear attractive to the modern eye but 60% of the light goes upward into the sky rather than down to where it’s of more use. The cost of that is twofold: increased light pollution and waste of resources by using more energy than is necessary.
As the industrial revolution developed through the 1800s and 1900s, a sign of the wealth of a town was seen in the number of chimney stacks belching smoke into the atmosphere. Today we no longer aspire to have those chimney stacks, seeing them instead as polluters of the world’s environment. Today how brightly we light our cities is seen as a sign of progress and wealth.
In how many years, the film asked, will light pollution be seen as another type of polluter, one that is affecting the health of humans, plants and wildlife alike?
We ask, should we be worried by this; should we try and have some influence on this problem, not just for the aesthetics but for the health of the planet and the people and wildlife that live on it?
Check out this website for links to further information about light pollution.