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Light pollution

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Light pollution is the alteration of natural light and dark patterns in ecosystems. This phenomenon results from the use of artificial lighting in poor or excessive ways. While it can occur during the day, its effects are most visible at night. This is because of the high contrast between artificial light and the dark sky. Light pollution is a major side effect of our industrial civilization. It affects human health, disrupts entire ecosystems, and spoils beautiful natural environments.

World light pollution
World light pollution

There are several distinct categories of light pollution. One type is light trespass, which occurs when unwanted light enters a specific property. For example, a strong outdoor light might shine through a bedroom window. This can cause sleep deprivation for the people inside. Another type is skyglow, which is a bright haze seen above cities. This haze is created when artificial light reflects and bounces around in the atmosphere.

Skybeamer-uniqema-640
Skybeamer-uniqema-640

Other types include glare, over-illumination, and light clutter. A single light source often falls into more than one of these categories.

Glare is a specific type of light that can be very disruptive. It is often classified into three different levels of intensity. Blinding glare is so bright that it can cause temporary or permanent vision deficiencies. Disability glare, such as the light from oncoming cars, reduces a person's ability to see clearly. This can happen when light scatters in the eye or reflects off dark areas. Discomfort glare is less dangerous but can be very annoying or cause fatigue. In some cases, bad lighting is considered a public health hazard.

HPS-lamps
HPS-lamps

Over-illumination refers to the excessive and unnecessary use of artificial light. This often happens because of improper design or incorrect choices in light bulbs. Many people also hold the misconception that more light always equals more safety. This is not a proven fact and can actually make problems worse. Over-illumination also leads to massive amounts of wasted electricity. In the United States, homes used 81 billion kilowatt hours of electricity for lighting in 2020. Commercial and manufacturing buildings used even more in 2018.

Las Vegas Strip
Las Vegas Strip

Light clutter is another way that artificial light causes problems. This occurs when there are excessive groupings of lights in one area. You might see this with brightly lit advertisements or poorly designed streetlights. Light clutter can be very distracting to people, especially drivers. These groupings of lights can generate confusion and even lead to accidents.

San Tan Mountain Lights
San Tan Mountain Lights

Because light pollution is a man-made phenomenon, addressing it involves complex social and economic factors.

Human awareness of these harmful effects began in the second half of the 19th century. However, organized efforts to fix the problem did not truly start until the 1950s. In the 1980s, a global dark-sky movement emerged to protect the night. This led to the founding of the International Dark-Sky Association (IDA). Today, many educational and advocacy organizations exist in countries all over the world. They work to teach the public and push for new legislative changes.

Melbourne (AU), Melbourne City Centre -- 2019 -- 1530-4
Melbourne (AU), Melbourne City Centre -- 2019 -- 1530-4

The scale of light pollution is quite large and continues to grow. It is estimated that 83% of the world's people live under light-polluted skies. In North America, 80% of people cannot see the Milky Way galaxy. Globally, light pollution increased by at least 49% between 1992 and 2017. About 23% of the world's land area is affected by skyglow.

Light pollution It's not pretty
Light pollution It's not pretty

We can help reduce these impacts by adjusting light fixtures or using better bulbs. Solutions like indirect lighting can also help manage how light is used.

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🖼️ Images & Media (17)
File:Melbourne (AU), Melbourne City Centre -- 2019 -- 1530-4.jpg
Melbourne (AU), Melbourne City Centre --...
File:Skybeamer-uniqema-640.jpg
Skybeamer-uniqema-640.jpg
File:Phoenix Lights from afar.jpg
Phoenix Lights from afar.jpg
File:HPS-lamps.jpg
HPS-lamps.jpg
File:Las Vegas Strip.png
Las Vegas Strip.png
File:San Tan Mountain Lights.jpg
San Tan Mountain Lights.jpg
File:Night sky at ESO's Paranal Observatory around twilight, Eso2004a.jpg
Night sky at ESO's Paranal Observatory...
File:World light pollution.jpg
World light pollution.jpg
YOUTUBE HQ-12573 blackmarble 2017 youtube hq.webm
File:Lichtverschmutzung in Kastelruth.JPG
Lichtverschmutzung in Kastelruth.JPG
File:Scorpion in arizona.jpg
Scorpion in arizona.jpg
File:Birds flying trace.jpg
Birds flying trace.jpg

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