Jari Lyytimaki, a research scientist at SYKE wrote about light pollution along with other environmental problems in a book called Forgotten Environmental Problems (2005). He finishes the book with a call to action to citizens to help reduce these problems.
Problems cited in this article include disturbance to sleep and hormone production, increasing exposure to breast cancer, the adverse affect on the behavior of animals, and orientation problems for migrating birds.
Additionally, poorly directed outdoor lighting creates unnecessary financial costs as well as wasted energy emissions. The International Energy Association (IEA) estimated “…the global sum of carbon dioxide emissions from the proportion of energy production used for illumination amounts to two thirds of the emissions from cars.”
If we don’t change our outdoor lighting habits, within the next 25 years we could be seeing an 80% increase in energy consumption directly related to nighttime illumination. On April 9th, 2012, the Helsinki Times reported that the situation has not improved since 2006 and in fact the problem of light pollution continues to worsen, increasing at a rate of between 6 and 20 percent in populated areas worldwide.
What can we do? Get rid of unnecessary and inefficient lighting. Replace existing lights with dark sky compliant fixtures. And, of course, turn off the lights when they are not needed, either by hand or with an outdoor lighting motion sensor.