As our society moves more towards the manufacture and use of environmentally sound products, it seems the number of stories we hear about pollution and its adverse effects on the environment also seem to increase. Improved awareness of environmental issues has lead to a greater effort to implement environmentally friendly solutions in transportation, in industry, and in our homes.
One form of pollution you do not hear much about is light pollution. Essentially, light pollution is the excessive or unnecessary use of artificial light. Light pollution has been scientifically linked to human health hazards, damage to the ecosystem, and interference with astronomers.
Light pollution is also a waste of energy. One U.S. Department of Energy statistic estimates two million barrels of oil are wasted each day in the United States due solely to over-illumination.
Adverse Environmental Impacts
Many species are nocturnal and depend upon the cycles of darkness and moonlight for survival. Studies have shown that excessive artificial light at night can affect the migration, mating, and basic survival instincts of many different creatures.
• Birds become confused by tall buildings and lighted towers, many times flying into them or colliding with other birds after becoming disoriented.
• Sea turtle habitats have become threatened because hatchlings need the moonlight to draw them to the sea. Excessive coastal lighting can attract the hatchlings away from the ocean and towards danger.
• Frogs, who depend upon darkness, become unable to mate when exposed to intense artificial light.
• Bioluminescent creatures such as fireflies and glowworms cannot communicate with each other when there is excessive artificial lighting.
Impact of Excessive Lighting on Astronomy
Astronomers’ ability to study the cosmos is most affected by sky glow and light trespass. Sky glow occurs when a portion of light from outdoor fixtures escapes upward into the sky, where it scatters. This is the type of light that causes a "glow" above major cities, and can interfere with sensitive astronomical instruments.
Light trespass occurs when lights are cast into unwanted areas, as can happen with poorly aimed or poorly shielded fixtures. This type of light can also interfere with astronomers.
Certain light sources, such as low sodium pressure lighting, are more astronomically friendly and is preferred in the vicinity of observatories.
Effects on Humans
Exposure to too much light at night interferes with human circadian rhythms, hindering the ability to get enough deep, restful sleep. This is compounded by light at night hindering the body’s ability to produce melatonin, the hormone that assists us in reaching deep sleep.
Scientific studies have also shown that exposure to excessive light at night can contribute to headaches, hypertension, loss of visual acuity, and can increase the incidence of certain types of cancer. Office workers exposed to excessive fluorescent lights at night showed an average jump of eight points in blood pressure.
Page 1 of 2 :: First | Last ::  Prev | 1 2 | Next 
|
