INTRODUCTION
Nature is plagued by various natural and man-made factors that have polluted the air, water and soil around us and now, as it turns out, light factors are entering into all of them as well. Electrical and artificial lighting were associated with economic growth and development. Unfortunately, the overuse of natural lighting has proven to have negative consequences.Rapid urbanization across the globe has resulted to exponential population boomed inhabiting the big cities and urban areas and this also means more people are now experiencing light pollution without even realizing it. Vigorous development and economic growth contributed to a sweeping increase in artificial light usage, which further deteriorate the natural dark sky. The night sky is getting brighter every year, as the light pollution becomes more prevalent.Nights are becoming around 10% lighter each year, which has implications for the health of both humans and wildlife. The stars are vanishing before our very eyes, as increasing levels of light pollution mean that increasingly fewer stars are visible in the night sky above us. The issue of light pollution is not only becoming more widespread, but it is also accelerating. This issue was first recognized in 1970s, when the astronomers began to see the impact of rapid increase in artificial light on their work. This paper attempts to analyse the measures for mitigating light pollution across the world by looking into the laws and regulations in this regard.
- Emergence of Light Pollution:
- Definition:
Light Pollution, known also as photo pollution, is the excessive, misdirected or obtrusive artificial (usually outdoor) light. It is a generic term meaning artificial light which shines where it is neither wanted nor needed. This is one of the least known types of pollution and the easiest anthropogenic pollution to address and reduce. The light pollution is observed mainly in large cities and is mainly identified by the absence of starry skies.
1.2 Types of Light Pollution:
According to the classification introduced in 1988 by the International Dark-Sky Association[1], the light pollution may occur in the following forms:
- The glare when the light source is directly visible and the contrast between it and the surroundings causes disturbance to the nocturnal vision[2] of living organisms is one such form of light pollutions. Examples are brightly lit ski slopes in winter, street lighting, and especially various typed of illuminated advertising installations, mainly LED billboards rapidly changing their brightness;
- The lighttrespass, treated as a violation of property boundaries, constitutes another form of light pollution. It occurs when the light source illuminates not only the dedicated area, but also the surrounding area. A typical example is the light of exterior street lamps illuminating the interiors of flats through the unprotected windows. Another example may be the lamps intended to illuminate roads leading through the National Parks and other protected areas illuminating the surroundings and, in doing so, disturbing the local nocturnal ecosystems;
- Grouping of light refers to a type of light pollution that arises when the density of artificial light sources in a particular area surpasses practical requirements. This is often observed in tourist destinations, where clusters of bright lamps are installed for decorative purposes, leading to overlapping illumination. In this way, grouped lighting also adds to other recognized forms of light pollution. Within cities, this issue may be seen in spaces such as parks or university campuses. It is also present around leisure facilities situated near, or even within, national parks, nature reserves, and other protected zones. The problem is particularly noticeable in the illumination of sports venues, including stadiums, ski slopes, and similar facilities.
- Sky glow is a form of light pollution resulting from the dispersion of artificial light on atmospheric aerosols. This is the most widespread category of light pollution as such dispersed light even reaches areas where none of the previously mentioned categories of light pollution are present. The sources of sky glow are improperly shielded lamp filaments or wrongly inclined lamp holders. Every single such light induces a local sky glow effect, which is important particularly in National Parks, reserves and other protected areas. However, it should be emphasised that exceptionally strong sources of this kind of light pollution are city glows, which have an impact upon and disturb even distant nocturnal ecosystems.
- Over illumination, is the excessive use of light well beyond that requires from a specific activity. Many indoor and outdoor locations have lights on when no one is around. This frequently extends beyond the requirement for security illumination. Examples include office buildings that have lights on all night even though the buildings are virtually empty or even landmarks, historic buildings, and attention-seeking skyscrapers.
- Light clutter, is the term used to describe excessively bright and confused group of lights. This is frequently observed in densely populated areas and overlit cities. The other forms of light pollution in metropolises are likewise brought on by the fast growth of light clutter. These kinds of light clutters can be confusing and result in numerous mishaps. In areas with inadequate illumination, particularly on roads and streets, and in areas with excessively bright advertising screens, clutter can be seen.[3]
1.3Causes of Light Pollution:
Natural light consists of the light from natural objects such as the sun and other celestial objects whereas, light pollution is caused due to the lightning through different sources and mediums. Various sources of light pollution include skyglow, lightning on the roadways, streets, automobiles, illuminated tall buildings, offshore and undersea vessels.
Outdoor lights used for residential, commercial, and industrial purposes are all poorly designed and greatly increase light pollution. Light pours into the sky since the majority of these lighting sources are operated at night.They significantly reduce natural light instead of being used in places that need illumination. As was already established, we are always surrounded by light trespass, which includes things like too much artificial light from the outside entering our rooms without our conscious awareness.
Poor planning and placement of streetlights has resulted from a lack of awareness of the problems that clutter, spillage, and excessive light illumination may cause to our surroundings.These strong light sources are frequently switched on all night long. These street lights illuminate many areas where they shouldn’t be, in addition to the cars that use the route. Roadway lights have been found to be responsible for between 35 and 50 percent of light pollution.
- Excessive use of light:
Another source of light pollution is careless light use, such as leaving lights on for extended periods of time and failing to reduce energy waste. Observing the sky has become extremely challenging due to the continually rising amount of light from towns and cities. A visible glow known as “skyglow” is created in towns and cities when light from different lighting sources is directed into the sky and dispersed throughout the atmosphere. Since it is challenging to see different celestial objects in the night sky, this also obstructs many astronomical observations. Light trespass is caused by tall buildings and structures such as lighthouses, towers, and wind energy turbines.
Cheaper substitutes, such as LEDs, have a number of unintended and deadly consequences, such as over use without the right protection or safeguards against excessive illumination. Excessive light is projected into the environment by extremely bright light sources such tube lights and bulbs, which has a detrimental effect. Among the streetlights are those white LEDs that produce shorter blue light waves, which cause skyglow and have a negative effect on the animals as well. Concerning outcomes also result from production facilities that handle oil or gas. The night skies are additionally contaminated by gas flares and industry in addition to night lights. Up to 2500 stars were visible to the unaided eye at night. This number has decreased over time to 200 to 300 stars, or even less than a dozen in urban areas due to increased light pollution.
Light pollution is man-made, much like all other forms of pollution, and it has gotten worse over the last few decades due to its exponential growth rate. Alongside the previously listed causes, other factors that contribute equally to the development of this hazard include smog, excessive lighting at night, bad planning, overcrowding, vehicle lights, etc.[4]
[1]DarkSky International, formerly the International Dark-Sky Association (IDA), is a United States- based nonprofit organization incorporated in 1988. The mission of the association is “to preserve and protect the night time environment and our heritage of dark skies through quality outdoor lighting”.
[2]Nocturnal vision, known also as scotopic vision, is the ability to see in very low light conditions, primarily using the rod cells in the retina rather than cones. This can be commonly seen in animals, which are referred as nocturnal animals like cats and owls.
[3] Komal Kaushik, Soumya Nair, Arif Ahamad, Studying Light Pollution as an emerging environmental concern in India, Volume 11, Journal of Urban Management ,394, (2022), accessed 01 Oct 2025
[4]Id. At 395.