There are many common sights in cities that are shocking to rural visitors. One of the most jarring is the almost ubiquitous presence of city light pollution. Away from large cities, the dark nights and the ability to see even very faint stars is often taken for granted, just as within cities their absence is little-noted. It may be odd to think of excess light as pollution at all - that term is usually reserved for chemicals that have dangerous effects on the environment. City light pollution, however, carries with it a multitude of problems, not all of them aesthetic. Thankfully, unlike chemical pollution, the ill effects of city light pollution can be reversed relatively easily. All that is required is greater understanding of the problem and a desire to seek out light pollution solutions.
Light pollution is a very broad term that covers a host of issues. Most often, however, light pollution refers to a general glowing of the sky that is prevalent in large cities. Light is scattered by metal, concrete, and glass up into the air, where it then reflects off of dust and smog, other common city pollutants. The result is a luminous haze hanging above the city, sometimes so bright that it resembles dawn in other, darker parts of the world.
City light pollution does more than simply block out the stars. The natural world relies heavily on the cycle between day and night. A constant dawn throughout the night can confuse and stress animals, domestic and wild alike, taxing their overall health. Indeed, people are among those animals that need dark nights in order to function properly. City light pollution has been linked to a host of problems, including stress, fatigue, high blood pressure, and even hormonal problems. The absence of darkness is dangerous for those who need it.
Another problem with city light pollution is the amount of wasted energy it represents. A significant percentage of the energy produced in the world, in some places up to half, goes directly to lighting. City light pollution arises when these lights are brighter than they need to be, or they illuminate more than they need to, resulting in excess light that escapes into the atmosphere - it is, in effect, wasted energy. A widespread effort to make city lighting more efficient could save billions of dollars in just a few years, as well as cut down on the number of greenhouse gases being emitted by power plants across the globe.
A focus on light pollution solutions is critical for health, energy efficiency, and general well-being. There are a number of steps that anyone can take in order to solve the problem. Homes and businesses can use softer lights that are not too bright for their purpose. They can install outside light fixtures that have a definite cutoff where the light is no longer needed, thus preventing it from escaping into the sky. Unnecessary lights can simply be turned off, or else operate on a motion sensor, so that they are only lit when they need to be.
Light pollution solutions can be more effective when undertaken in groups. Organizations like the International Dark-Sky Association exist to raise awareness and implement change in cities across the globe. Local homeowners' associations and chambers of commerce can take steps to reduce light pollution on a broad scale, and these groups may be surprised at the increased worker efficiency and morale that come with lower stress and less fatigue. Light pollution solutions can not only provide people with an unimpeded view of the beauty of the heavens, but can also raise general quality-of-life for people who may never have known what a truly dark night looks like. Take steps to talk to your community leaders about seeking out light pollution solutions in your area. It is a simple task that could have drastic benefits in the near future.