LIGHT POLLUTION

These days we often hear about pollution in its various forms but another form of pollution – light pollution - is a  problem which many people are not aware of.  Light pollution is gaining increasing attention from astronomers, environmentalists and people who wish to reduce energy consumption.

What is light pollution?  The International Dark Sky Association  defines it as the inappropriate or excessive use of artificial light. There are four components of light pollution - glare, skyglow, light trespass and clutter.

Glare is excessive brightness that causes visual discomfort and skyglow is the light halo over inhabited areas.  Light trespass occurs where light falls where it is not intended or needed and clutter happens where groupings of light sources produce a bright, confusing effect.

The Dark Sky Association points out that much outdoor lighting used at night is inefficient, unnecessarily bright, poorly targeted and not properly shielded which means it is spilling into the sky rather than doing the job it was intended for.  This of course means that much of the electricity used to create it is being wasted.

According to a 2016 study, 80% of the world’s population lives under skyglow.  Major population centres like the United States and Europe are heavily impacted.  There 99% of people are unable to experience natural night.

While skyglow away from our major cities is not as bad as in Europe, the US and Asia, we are still affected by it. Even in comparatively small population centres like Grafton we do not see the night sky in all its glory. If you visit areas in western NSW away from towns and look at the night sky on a cloudless night, you are likely to be amazed at the clarity of the heavens and immense number of stars.

Light pollution is not a concern merely because of aesthetics and the need to conserve energy.  It has impacts on human health and disrupts ecosystems and wildlife – effects which will be discussed in a future “Voices of the Earth” column.

For more information in the meantime, check the Dark Sky website - http://darksky.org 

           
 - Leonie Blain

This article was originally published in the VOICES FOR THE EARTH column in The Daily Examiner on June 5, 2017.    

DARK SKY TOURISM A POSSIBILITY FOR THE NSW NORTHERN RIVERS ?

Photographs of the earth taken from space at night show the extent of light from human habitation. So much of the night sky is lit up from below that around half of the world’s population cannot see the stars. In the United Kingdom the 2013 Star Count revealed that only 5% of the population could see more than 31 stars on a good night.

While Clarence Valley urban areas do not have as much light pollution as cities, our view of the night sky is still limited by light pollution.  Travelling through the darkened countryside towards a town or city, you will notice a halo of light above the settlement from many kilometres away. This restricts what can be seen of the heavens from the lit area.

What a contrast there is if you visit sparsely populated areas of Australia away from settlement!  On a clear night there the stars are dazzling in their numbers and intensity.

Observation of the stars, once the preserve of professional astronomers, now attracts many non-professionals and astrotourism is growing.  Around the globe there are areas which have been given “Dark Sky” status – places where it is possible to see the heavens clearly and these are attracting increasing numbers of tourists.

One of these is the UK’s Northumberland Dark Sky Park, around 1,500 sq km in northern England.  Another is the 4,300 sq km Aoraki Mackenzie Dark Sky Reserve on New Zealand’s South Island.  In the United States, even though light pollution is a major issue around the large population centres, there are many designated Dark Sky areas.  These include Death Valley National Park, Canyonlands National Park, and Natural Bridges National Monument.

Dark Sky status is conferred by the International Dark-Sky Association (IDA) which is based in  Tuscon, Arizona. Areas applying for the status are required to have taken major steps to avoid light pollution and to have proved that their nights are sufficiently dark.

While Australia does not have any areas with Dark Sky status, it has places – some in our region - which could qualify and potentially boost tourism.

-          Leonie Blain

This  post originally appeared in the VOICES FOR THE EARTH column in The Daily Examiner on 28th  March, 2016.