Light Pollution

In recent years when people have started to pay attention to various pollution and environmental issues, light pollution seems to have received little attention. However, light pollution has become one of the most common problems facing both developed and developing countries today.

What is light pollution?

Light pollution is excessive, misleading, or abrupt artificial light. Like noise pollution, light pollution is a waste of energy that can have adverse effects and degrade the quality of the environment.

What causes light pollution?

According to the National Geographic article Our Vanishing Night, light pollution is mainly due to inefficient lighting design. This results in artificial light always shining upward into the sky where it is not needed, instead of focusing downward for people to use. Common sources of light pollution include street lights, parking lot/mall lights, exterior promotional lights on most homes or businesses, neon signs, and illuminated signs.

And what are the effects of light pollution?

The serious consequences of light pollution can be seen in three main areas: damage to human health, damage to ecosystems, and an extreme waste of energy.

Adverse effects on human health

First, human beings have become accustomed to the 12-hour natural light and 12-hour darkness day-night cycle. Such a circadian pattern has become a habit for human beings, and the presence of night light will greatly affect its normal cycle.At the same time, night light greatly affects the production of melatonin. Melatonin is a potent antioxidant and anti-cancer agent and helps to regulate metabolism and immune response. Melatonin production is influenced by light and darkness. If humans are exposed to light while sleeping, melatonin production will be suppressed. This can lead to sleep disorders and other health problems such as increased headaches, glare in the eyes, increased stress as medically defined, obesity due to lack of sleep, and increased anxiety.

Harm to animals in the ecosystem

The light used by humans shines everywhere in the natural world. As a result animal life is affected by migration, breeding, hunting, and foraging. The case of sea turtles, for example, illustrates the problem greatly. Sea turtle hatchlings instinctively move toward the brightest light source. Because before humans began using artificial light sources, starlight reflected from the ocean was the brightest thing for sea turtles to see. But as the lights of coastal cities fill the night, these hatchlings become confused and disoriented, heading toward the city instead of the ocean and eventually falling victim to dehydration and predation without ever reaching the safety of the ocean. Hatchery losses in Florida alone amount to hundreds of thousands per year.

The economic impact of the resulting energy waste

The International Dark-Sky Association estimates that 1/3 of all lighting is wasted, costing the world an estimated $2.2 billion annually due to excessive light usage. In addition, light is usually generated by electricity, which itself is usually generated by the burning of fossil fuels. Therefore, there is a strong relationship between light pollution and air pollution. Controlling light pollution will help save fuel and money and greatly reduce air pollution and other environmental problems caused by excessive light.

What can we do?

TURN OFF THE LIGHTS!

The most effective solution to light pollution is to turn off the lights! When we must turn on the lights, we can also greatly avoid light pollution by using fully shielded, efficient lighting fixtures. Because they prevent light from being wasted outside the area we want to illuminate. Fully shielded fixtures prevent light from traveling horizontally and stop it from traveling upward.

Sources：JMU: Light pollution: The overuse & misuse of artifical light at night, Globe at Night