We have all heard of water pollution and air pollution. Furthermore, most people would not argue the fact that they are indeed a problem. However, light may be the only source of pollution that is overlooked by the average consumer. That may be because the average person does not think “light” when the word pollution comes up in the news or in conversation. After all, it is just light right? No, it is actually not that simple. Light pollution is defined as the lightening of the night sky due to artificial light being scattered about, it is also known as sky glow. Unnecessary light not only wastes massive amounts of electricity, but it adversely affects wildlife as well.
Light pollution, also called sky glow, is defined as light wastefully escaping into the night sky and causing a glow over urban/suburban areas. It also refers to light that is
being refracted in the surrounding atmosphere. This refraction is strongly related to the wavelength of the light. Rayleigh scattering, which makes the sky appear blue in the daytime, also affects light that comes from the earth into the sky and is then redirected to become sky-glow, seen from the ground. As a result, blue light contributes significantly more to sky-glow than an equal amount of yellow light. Sky glow is of particular irritation to astronomers, because it reduces contrast in the night sky to the extent where it may even become impossible to see the brightest stars.
So, what kind of lighting is harmful? The truth is that there are indoor and outdoor lighting that can be harmful in the long run. Research has been being done on the subject for years and it is well known that indoor fluorescent lighting can cause many health problems such as migraine headaches, fatigue, irritability and many other health conditions. But as for the outdoor environment, nighttime security lighting poses the biggest threat in terms of light pollution. Moreover, studies have shown that outdoor security lighting does not reduce crime, and uses approximately 800 pounds of coal each year per light. Have you ever looked up into the sky at night only to see a haze of dim light? This is the perfect example of light pollution. Researchers have been studying this problem for years and have produced actual photographs of landmasses, cities and rural areas around the world at nighttime. The results spoke for themselves; nighttime light is definitely a problem.
Light that is considered annoying, wasteful or harmful causes damage to the environment and health, as do other forms of pollution.Some indoor and outdoor lighting are considered harmful in the long run, It is well known that indoor fluorescent lightning can cause many health problems such as migraine, headaches, fatigue, irritability and many othe health conditions. Approximately 800 pounds of coal each year is wasted on per light. Outdoors, light pollution harms nocturnal wildlife.
Constant lighting could destroy crops, trees and even wildlife. Plants depend on the cycle of light and dark for proper growth. The onset of darkness is crucial to the flowering and reproduction process. Birds have been known to fly into towers and windows at night due to the confusion caused by nighttime lighting. The fact that night should be dark in not always the case nowadays. In some places like Las Vegas, you cannot even tell
if it is night or day because the billions are so bright you feel like you are in another dimension.
Life existed in fixed natural cycles of light and dark, so disruption of those patterns influence many aspects of animal behaviour. Light pollution confuses animal navigation, alter competitive interactions, change predator-prey relationships and influence animal physiology. Studies suggest that light pollution around lakes prevents zooplankton from eating surface algae, causing algal blooms that kill off the lake's plants and lower water quality. Nighttime light also interferes with the ability of moths and other nocturnal insects to navigate. Night blooming flowers that depend on moths for pollination will be affected by night lighting. This leads to species decline of plants that are unable to reproduce and change an area's long-term ecology.
Lights on tall structures disorient migrating birds. The number of birds killed after being attracted to tall towers is estimated to be from 4-5 million per year. The fatal Light Awareness Program (FLAP) works with building owners in Toronto, Canada and other cities to turn off lights during migration periods to reduce the mortality of the birds.
Contrary to misconception, sea turtle hatchlings are not attracted to the moon. Rather, they find the ocean by moving away from the dark silhouette of dunes and their vegetation, a behaviour that artificial lights interfere with. Lights may also disorient young seabirds as they leave their nests and fly out to sea.
Nocturnal frogs and salamanders are also affected. Since they are nocturnal, they wake up at night. Light pollution causes salamanders to emerge from concealment later, giving them less time to mate and reproduce.
So to do your part for the environment, make sure that your exterior lighting is ordinance compliant lighting. By this, is meant that only light the ground beneath them and never shine across onto a neighboring property or into the night sky. Secondly, by making sure that your outdoor lights are only on when needed. Dusk to dawn lighting is to be strictly avoided. Thirdly, reduce the wattage of your bulbs. The human eye is remarkable in its ability to adapt to the amount of light present. Too much light can be overwhelming and glaring, actually reducing visibility. Even a small reduction in wattage will reduce light pollution.