We are currently in the middle of International Dark Sky Week, initiated by the International Dark Sky Association running from April 5-11 of 2013. The purpose is to raise awareness of the increasing problem of light pollution around the globe. Most people are aware of light pollution and even poke fun at the fact of how few stars they see while at the same time reminiscing or even hoping for a chance to see a dark, night sky again.
The effects of light pollution deserve much more attention than they get however. It is not just that it prevents humans from seeing a few extra stars at night, it has real health effects that affect both humans and all wildlife in the area. The most obvious concern is the effect of light pollution on a person’s circadian rhythm. With consistent light pouring in all around throughout the night and day, the rhythm gets disrupted resulting in a much higher potential for insomnia, depression, cancer, and cardiovascular disease. Likewise, this also disrupts the production of melatonin in the body which normally regulates cell metabolism in the human body, reducing the risk of cancer and other diseases.
With wildlife, the results can be fatal much quicker. Many birds are most active at night and would normally use the faint light of dawn to guide them. With excessive light pollution, the light veers them off course, and as they keep flying to try figure out where they are, they burn up their energy and often die of exhaustion. Others continue to track down the source of the light and wind up colliding with buildings or towers. Reptiles also are especially vulnerable. Female sea turtles often have trouble finding a dark beach to lay their eggs on. This leads to them spending more energy than they need to and also a decrease in the population should they not be able to find a suitable location. Should they succeed, they lay their eggs trusting that the moonlight and night sky reflecting off the ocean waters will be the brightest source of light to guide the newly hatched offspring to safety. With nearby light pollution, however, the young hatchlings often work their way toward the wrong direction, bringing them into contact with roads or dehydrating them completely. Even migrating animals, such as elk, are confused by light pollution, affecting their normal sleep patterns and migratory routes.
The good news is there are solutions that you can implement that are not only effective in reducing light pollution, but are also very cheap. The first and easiest thing to do is to make sure your house does not give off more light pollution than it should. If you need indoor lights on at night, use blinds or curtains to minimize the light escaping from your house. For outdoor lights, you can install motion detectors so that they are only used when needed, as well as equipping them with shades or cutoff fixtures. This will ensure that the light is pointed down where it is really the only place it is needed, rather than arbitrarily outward which floods the night sky with unnecessary light. Taking simple steps like this will also inspire your neighbors, friends, and family, which will have an effect on them as well, especially if you inform them of why you made such changes. If you really want to have a positive impact, you can also communicate with businesses that point lights into the sky or outward and inform them of the effects they are causing. The worst thing that can happen from it all is that you see a few extra stars at night. The best thing that can happen is that you help save a life.