Light Pollution

Light pollution is light that shines where it is not needed or wanted…. light that trespasses, light that glares, light that shines up into the sky. Such light:


  • damages the health of humans, animals of all kinds, and plants by interfering with their natural rhythms  (you don’t sleep as well when your bedroom is not dark);
  • wastes energy and money leading to the emission of more greenhouse gases, higher taxes and energy bills, and
  • has been shown to actually reduce security and safety while encouraging crime.

The need for action is great. One quarter of all energy consumption used worldwide is used for lighting. And the Calgary area uses far far too much light – SEVEN times as much per square foot as Vancouver. We are terrible light polluters and here in Cochrane can usually only see the Milky Way as a blur.

Check out this new video from the International Dark-Sky Association in collaboration with Loch Ness Productions, a U.S.-based full-dome planetarium show production company.

Losing the Dark


Light Pollution Map of Calgary and Area


Typically, 30 to 50% of the light we produce is never used, shining sideways or upwards instead. Misdirected light, using too much light, and leaving the lights on all night are all wastes of energy. Calgary Roads estimated that about $2 million dollars of taxpayers’ money per year was being sent skyward due to over-lighting with inefficient streetlights – because of this they embarked on a massive program to change them, and, thanks to the Mayor and Council, so has Cochrane. You must have noticed how the new cut-off streetlights provide plenty of light without dazzle, and they don’t shine into upstairs bedrooms any more.

Cochrane businesses on the whole have made significant efforts to reduce light pollution. Canadian Tire is exemplary while the glare from other businesses with tall lights can actually interfere with driving down the Big Hill, besides inviting graffiti artists to adjacent walls. Some municipal facilities still have inappropriate lighting.

What can the private citizen do to reduce light pollution?

Make sure any outside lights shone only where, when and as brightly as is really needed. Photo-cell activated lights for porches can be adjusted to shine brightly when you come home with the shopping or someone comes to your door, but dimly and cheaply the rest of the time. Change in illumination warns the householder and discourages criminals far more than a bright exterior light that it is always on, providing shadows for burglars and muggers to hide in. Time-activated lights may also be useful and, for general energy saving, switch to long life compact fluorescent bulbs.

CEAC is committed to reduction and eventual elimination of light pollution. To this end we have supported the annual Earth Hour lights off demonstration, sponsored by the World Wildlife Fund for Nature, and claim some responsibility for Cochrane having come second in province in reduction of electricity usage during Earth Hour 2010. Members of CEAC have for some years been organizing public viewings of the sky and its marvels through more and increasingly large telescopes during Earth Hour (Saturday March 23, 2013 at Mitford Park) and again in the Fall. Come and join us!

CEAC intends to work towards the declaration of Cochrane as an urban dark sky preserve.

For further reading on light pollution and related topics, see:

The Earth Hour site is What you find may encourage you to turn off your lights during Earth Hour and conserve electricity 365 days a year.  So may a view of the sky on a clear dark night.

Participate in the 2013 Globe at Night project to help track the extent of light pollution in Cochrane and around the world.

2013 Dates for GLOBE at Night

In 2013 there will be four opportunities to participate in GLOBE at Night:

March 3-12      March 31 – April 9          April 29 – May 8

GLOBE at Night program is an international citizen-science campaign to raise public awareness of the impact of light pollution by inviting citizen-scientists to measure their night sky brightness and submit their observations to a website from a computer or smart phone. Light pollution threatens not only our “right to starlight”, but can affect energy consumption, wildlife and health. The GLOBE at Night campaign has run for two weeks each winter/spring for the last six years. People in 115 countries have contributed 66,000 measurements, making GLOBE at Night one of the most successful light pollution awareness campaigns.

More information here.  GLOBE AT NIGHT 2013





Cochrane-Light-Pollution-Key (Click to download as full-size PDF)