Light pollution, unwanted or excessive artificial light. Like noise pollution, light pollution is a form of waste energy that can cause adverse effects and degrade environmental quality. Moreover, because light (transmitted as electromagnetic waves) is typically generated by electricity, which itself is usually generated by the combustion of fossil fuels, it can be said that there is a connection between light pollution and air pollution (from fossil-fueled power plant emissions). Control of light pollution therefore will help to conserve fuel (and money) and reduce air pollution as well as mitigate the more immediate problems caused by the excessive light. Although light pollution may not appear to be as harmful to public health and welfare as pollution of water resources or the atmosphere, it is an environmental quality issue of no small significance.
Light pollution adversely affects professional and amateur astronomers, as well as casual observers of the night sky, because it severely reduces the visibility of stars and other celestial objects. The reduction in night sky visibility is a result of “skyglow,” upward-directed light emanating from poorly designed or directed lamps and security floodlights. This wasted light is scattered and reflected by solid or liquid particles in the atmosphere and then returned to the eyes of people on the ground, obliterating their view of the night sky. The effect of skyglow from a town or city is not necessarily localized; it can be observed far from the main source.
Light pollution is a problem not only for astronomers and people who simply want to enjoy the beauty of a starry night. Glare from road lamps, commercial security lights and signs, or even from a neighbour’s bright and misdirected yard lighting can cause discomfort and distraction and adversely affect the quality of life of many people. Light pollution also has adverse impacts on birds and other animals. Many migratory birds, for example, fly by night, when light from the stars and Moon helps them navigate. These birds are disoriented by the glare of artificial light as they fly over urban and suburban areas. It has been estimated by the American Bird Conservatory that more than four million migratory birds perish each year in the United States by colliding with brightly illuminated towers and buildings. Light pollution is considered to be one of the contributing factors in the dramatic decline of certain migratory songbird populations over the past several decades.
Experiments have demonstrated that street lighting also reduces moth caterpillar abundance, when compared with unlighted areas, and is linked to slowed caterpillar development. In addition, studies have shown these disruptions were more evident when streetlights were outfitted with LEDs (light-emitting diodes) than yellow sodium-vapour lamps.
The quantity of light pollution from a given area depends on the number and brightness of light sources on the ground, the fraction of light that escapes above the horizontal, the reflectivity of surfaces near the light sources (e.g., roads, pavements, walls, windows), and the prevailing atmospheric conditions. Empirical formulas allow the calculation of skyglow levels as a function of population and distance from the observer. When skyglow levels are more than 10 percent above the natural background levels, significant sky degradation has begun. Even lights from a fairly small town with a population of only 3,000 people will cause significant night sky degradation for an observer as far as 10 km (6 miles) away.
Light pollution can be reduced by using well-designed light fixtures with modern optical controls to direct the light downward and also by using the minimum amount of wattage for the area to be illuminated. National and local government agencies can help by passing and enforcing appropriate light-control laws and ordinances.
Types of Light Pollution
- Over-illumination
- Light trespass
- Light clutter
- Glare
- Skyglow
Over-illumination
The term over-illumination refers to excessive use of light.
This excessive use of light leads to excessive consumption of electricity, which in turn causes pollution and other adverse effects on the environment.
Light trespass
Light trespass happens when light is affecting you from an outside source, like your neighbor turning on a bright light that shines through your windows.
Light clutter
Light clutters can be defined as an excessive grouping of lights.
This can be particularly dangerous when you drive a car and get distracted from these light clutters which may result in severe accidents.
Glare
Glare commonly refers to an effect of lights from which you can get blinded or have vision deficiencies.
Skyglow
Skyglow can be the result of either artificial lights or also natural light sources like starlight.
It describes the effect that the outside environment is bright even at night.
Causes of Light Pollution
- Excessive use of light
- Overpopulation
- Infrastructure planning
- Garage lamps
- Light from houses
- Downtown areas
- Smog and clouds
- Cars and other motor vehicles
- Nighttime-lighting
- Streetlamps
Excessive use of light
One cause of light pollution is the excessive use of electric light.
Since electricity has become quite cheap over time, people do not care too much about their electricity consumption.
This results in an over-consumption of electricity and also in excessive use of light.
Especially at nighttime, the use of electricity can cause severe light pollution which may affect neighbors in an adverse way.
Overpopulation
Overpopulation is another source of light pollution.
This is quite intuitive since overpopulation usually leads to a higher population density.
A higher population density implies an increasing use of electronic devices and also of lights.
This in turn leads to a higher level of light pollution.
Infrastructure planning
Decent infrastructure planning is crucial in order to be able to confine the adverse effects of light pollution.
For example, if streetlights are placed too near to houses, the people living in these houses may be adversely affected by light pollution.
Garage lamps
Garage lamps can be an additional source of light pollution.
For instance, when a neighbor turns on the garage lamp at nighttime, this light may also reach nearby houses and thus cause light pollution for the affected people.
Light from houses
There can also be light pollution simply because the neighbor just leaves on the lights even late at night.
This light may reach nearby houses and affect the people living nearby, thus resulting in light pollution.
Downtown areas
Since downtown areas usually are quite illuminated, they also contribute to light pollution in a significant way.
Especially if you live in these areas, chances are that you will be significantly affected by light pollution since many of the lights will stay on 24/7 for traffic but also for commercial purposes.
Smog and clouds
Smog and clouds can reflect the light which is emitted by cities and thus make the surrounding environment look much brighter which can be regarded as light pollution.
Cars and other motor vehicles
Cars and other vehicles also contribute to the problem of light pollution.
Especially at nighttime, the lights of cars shine quite bright in areas where there are not many other light sources.
Thus, the sleep of people may be adversely impacted by the lights of cars, especially if people live near streets that have a high traffic density.
Nighttime-lighting
Nighttime-lighting of all sorts can affect people in a negative way and thus cause light pollution.
For example, advertising spaces that are illuminated at nighttime may cause light pollution to the surrounding houses.
Streetlamps
Streetlamps may also cause light pollution and may affect people if they are built too near to houses.
Due to poor street planning, this might occur from time to time.
As a consequence, the pollution coming from streetlights may impact people’s sleep in an adverse manner.
Effects of Light Pollution
- Health effects
- Effects on traffic
- Sleeping problems
- Pollution of the air and atmosphere
- Global warming
- Effects on astronomy
- Waste of resources
- Effect on ecosystems
- Effects on animals and plants
Health effects
Light pollution can cause major adverse health effects.
Since peoples‘ sleep may be affected through light pollution, bad sleep can lead to all kinds of health conditions, including heart attack and also mental problems.
Moreover, the stress level for people exposed to light pollution is likely to be increased, which can also result in cardiovascular problems like heart attacks.
Effects on traffic
Light pollution may also have an adverse effect on traffic.
Since too much lighting or the wrong angle may cause temporary blindness, this can be a serious issue when it comes to driving a car.
If your sight is adversely impacted, for example through excessive light clusters on certain streets, the probability for accidents may increase.
Sleeping problems
Sleeping problems may be another effect of light pollution.
Many people are not used to distractions from light when they are sleeping. People usually prefer to sleep in a dark environment.
When this environment is changed into a brighter state, people may suffer from sleeping issues, which in turn can result in serious health conditions since enough sleep is vital for our physical and also for our mental health.
Pollution of the air and atmosphere
Light pollution also leads to pollution of the atmosphere.
Since for the illumination at night, huge amounts of electricity are used, this leads to a high level of CO2 emissions and other harmful gases.
Global warming
Through light pollution and the resulting pollution of air with CO2, the global warming process is enhanced since CO2 is considered a greenhouse gas.
Emitting high levels of CO2 into the atmosphere supports climate change progress.
Thus, light pollution also contributes to the global warming issue.
Effects on astronomy
Light pollution may also affect astronomy in an adverse way.
Since it is usually beneficial for astronomists to have a dark environment in order to spot stars and galaxies, too much surrounding light may harm the observation process.
This problem is especially severe in big cities which are usually quite bright even at nighttime.
Waste of resources
Through excessive use of light, many fossil resources are consumed every day.
For example, in order to produce electricity, huge amounts of coal are used in industrial processes.
This means, by using electricity, we are also indirectly contributing to the depletion of natural resources like coal.
Effect on ecosystems
Whole ecosystems can be adversely affected by light pollution.
Since these ecosystems are usually quite sensitive to changes in their environment, they may not be able to adapt to new conditions properly.
Since light pollution is an artificial effect caused by humans which does not occur in nature at scale, chances are that ecosystems may be confused and affected in an adverse manner.
Effects on animals and plants
Light pollution may also affect animals and plants living near cities.
This effect may be especially severe for regions that had previously been untouched by humans.
Animals in these areas may react quite sensitive to the changes in their natural environment and may move to other places with lower light pollution.
Solutions to the Light Pollution Problem
- Light shields
- Warm lighting
- Cut off light
- Certifications
- Motion sensors
- Turn off the lights
- Make your contribution
- Convince others
Light shields
Light shields are a measure against light pollution in the sense that they can prevent light to spread to nearby areas and concentrate the light on certain spots.
This helps to mitigate the problem of light pollution for nearby houses and their inhabitants.
Thus, light shields can prevent light pollution and the implied negative consequences.
Warm lighting
Using warm lights instead of cold lights can also mitigate the problem of light pollution.
While cold short wavelength light impairs night vision and contributes to light pollution, warm light is known to prevent this adverse effect to a certain degree.
Cut off light
Another solution to the light pollution problem is to cut off light.
Through light cutoffs, the angle in which the light is spread can be determined.
Thus, nearby houses can be released from light pollution since the light is concentrated on certain spots where it is needed and therefore does not affect the surrounding environment.
Certifications
You can also use certified lighting which is meant to reduce sky glow, glare and light spill to a significant degree.
Certain certifications like the IDA guarantee that the impact of your lights on the environment and therefore light pollution is reduced to a minimum.
Motion sensors
Motion sensors are a great way to reduce light pollution.
Since the light only is turned on when the motion sensor is triggered, it can save a lot of energy.
Moreover, also the light pollution is reduced significantly since the light only turns on in very few occasions.
Thus, motion sensors can effectively reduce the light pollution issue (at least if not too many cats are around
Turn off the lights
Another quite obvious but yet not less important measure against light pollution is to simply turn off the lights as often as possible.
This has several beneficial effects on your neighbors as well as on our whole environmental system.
The light pollution imposed on your neighbors will be reduced significantly if you turn off your lights.
Your neighbors will especially thank you for this at nighttime.
Moreover, by turning off the lights, you can save plenty of energy which in turn means less air pollution.
It also slows down the global warming issue.
Thus, turning off the lights is one easiest and also one of the most effective ways to prevent the adverse effects of light pollution.
Make your contribution
As you have seen in the previous analysis, your daily actions have a significant effect on the level of light pollution.
This is an important fact to note.
In our nowadays society mindset, we are quite fast of blaming others instead of blaming ourselves for things that go the wrong way.
Instead of pointing to others, we should also ask ourselves how we can make an impact in order to reduce light pollution in our daily lives.
Convince others
Making your impact is important!
However, you can make an even greater positive impact if you are willing and have the courage to convince other people.
See it that way: You can only reduce light pollution in your daily life to a certain degree.
However, you can convince hundreds or even thousands of people on a daily basis.
This may include talking to your friends, but it can also mean starting a blog and influence many people in this way.
All this will make a great impact in order to mitigate the issue of light pollution and will also tackle many other global problems we currently face.
Conclusion
Light pollution is a significant problem in our nowadays society.
Although it may not seem like a big issue compared to other problems like global warming, it still causes severe problems on humanity as well as on our whole environmental system.
These include adverse impact on our sleep which is likely to increase our stress levels and in turn may even lead to cardiovascular diseases like heart attacks.
There are plenty of measures which we can apply in our daily lives to reduce the adverse effects caused by light pollution.
Most of these measures are quite easy to apply and also do not cost lots of money.
This means it all depends on our will to change our behavior in order to prevent light pollution and the implied adverse effects.
If everyone contributes just a little bit, we could greatly reduce light pollution and therefore increase our living quality.
标签：lights,may,Light,also,light,Pollution,pollution From： https://www.cnblogs.com/lhxl521/p/17795857.html