What is Light Pollution?
Light pollution is inappropriate, unwanted, excessive, misdirected, or invasive use of artificial outdoor lighting. It is also known as luminous pollution or photo pollution.
Over-illumination, glare, light clutter, sky glow, light trespass are some types of light pollution. Light pollution hinders the appearance of stars at night and also has adverse effects on the environment.
What are the Causes of Light Pollution?
Humans are solely responsible for light pollution. Following are some of the causes of light pollution:
- Poor planning in the placement of street lights and signage.
- Irresponsible use of light.
- Zoning issues due to overpopulation which groups too many businesses or residential buildings in one area.
- Excessive use of light, especially at night time as electricity has become relatively cheap over time.
- Light emitted by cities is reflected in smog and cloud, which makes the surrounding environment look much brighter.
- Lights coming from cars and other vehicles.
- Poor design of outdoor lights contributes significantly to light pollution.
What are the Effects of Light Pollution?
Effects on Humans
Production of melatonin in humans is delayed when our circadian rhythm is exposed to excessive artificial light. This disrupts the sleeping pattern, makes it take longer to fall asleep at night, and has an adverse impact on health, leading to depression and insomnia.
Effects on Animals
Light pollution adversely affects the feeding, sleeping, mating, and migration cycles of all animals. Some birds use darkness for hunting and migrating, but it fails to migrate due to high-intensity light in urban areas. Light pollution affects nocturnal animals that hunt during the night, become vulnerable, and are therefore more likely to be hunted.
Effects on Astronomy
Over 95% of stars visible to the naked eye are now invisible due to light pollution. This creates important and critical issues in astronomy. Artificial light interferes with astronomical equipment and makes viewing celestial bodies difficult even with the aid of a telescope.
How to Prevent Light Pollution?
Light pollution can be prevented by proper planning and educating people. Here are some of the point to prevent light pollution:
- Proper planning for the placement of light sources.
- Using light shields to prevent the spreading of light to nearby areas.
- Using advanced technology like motion sensors to automatically turn light on and off.