Mitigating the Negative Effects of Light Pollution

Transcription

1 8 th session of Budapest International Model United Nations Introduction Mitigating the Negative Effects of Light Pollution The Earth by night is growing brighter and brighter day by day. But does a brighter Earth mean a brighter future for the world? Less than a century ago, while looking up to the sky at midnight we would be able to see the stars, sometimes even Zodiac signs or the Milky Way. Nocturnal birds and animals were not disturbed by the bright lights in night-time. 100 years ago, light pollution was not even an issue. Artificial light used to be a rare phenomenon, something to which only a few had access to. Due to technological development the situation has changed significantly since then and made the improvement of infrastructure possible. The benefits of artificial light has gradually evolved into one of the biggest harmful factors for the Earth. As a side-effect of urbanization, the massive use of artificial light sources has slowly become an excessive and obtrusive consumption of electricity, causing light pollution. Despite the usefulness of artificial light sources, their overuse has serious effects on humans and animals, since it intervenes in the natural day-night pattern, not to mention the waste of energy and resources. For a while, the question of light pollution has been ignored, however, lately more and more organizations are trying to raise awareness, in order to prevent causing an irreversible damage to our environment. Light pollution is responsible for environmental damage as well as for accidents due to disturbance by outdoor lighting, however, as the latter varies from region to region, our main focus should be on the environmental damage, a problem that is crucial to tackle on a global scale as soon as possible. Definition of Key Terms Nocturnal: active during night-time, e.g. nocturnal birds such as owls. Diurnal: active during daytime, e.g. humans. Light: electromagnetic radiation within a certain portion of the electromagnetic spectrum. The word here refers to light that is visible for the human eye. Luminance: At a point and in a given direction, the luminous intensity in the given direction produced by an element of the surface surrounding the point divided by the area of the projection of the element on a plane perpendicular to the given direction. Ambient light: the general overall level of lighting in an area Light pollution: Any adverse effect of artificial light including sky glow, glare, light trespass, light clutter, decreased visibility at night, and energy waste.

2 Anthropogenic light: Light produced by artificial light sources. Its excessive use leads to light pollution. Light-trespass: A light trespass occurs when light shines beyond the intended target, where it is unwanted. E.g. light shining over a neighbour s fence is a lighttrespass. Sky glow: The brightening of the night sky created by artificial light sources, usually over inhabited areas. Sky glow reduces the ability to view the night sky. Glare: Glare is produced by the luminance within the visual field that is greater than the luminance to which eyes are adapted to. It causes a loss in visibility, which can result in accidents. E.g. a sufficiently bright lamp along the road while driving causes confusion and temporary loss of visibility. Over-illumination: The excessive use of light. Clutter: bright, excessive grouping of light sources, often found above over-lit areas. A clutter might create confusion and distraction from obstacles, thus very often causing accidents. Ecological light pollution: the phenomenon when ecosystems and organisms are exposed to excessive amounts of artificial light. Photic zone: the surface layer of the ocean which receives sunlight. Background For hundreds of millions of years, life on Earth existed in a natural rhythm, where the change of day and night was dominated by the Sun, the Moon and the stars, whereas now, artificial light fill the darkness. Cities glow for long hours after nightfall, disturbing the balance of the Earth and its creatures with over-illumination. Light trespass, over-illumination, glare, light clutter, and sky glow all fall into the definition of light pollution, and their combination is what causes the most harm to humans and the environment. As humans, we are diurnal species, meaning that our eyes evolved to function best in daylight. Even though our eyes can adapt to the darkness reasonably fast, we still cannot function the way nocturnal creatures can without daylight. Because of that, we started using different sources of light to extend the daytime in order to be able to conduct and continue our activities even after nightfall. Initially, light was first used for safety.

3 Cavemen used light because they feared the dangerous animals of the night. After discovering the fear from fire in predators, our ancestors learned how to light a bonfire themselves. Besides making food tastier and more edible by roasting it, the main function of bonfires was to keep predators away from human shelters after dusk. Simply by allowing men to see even in darkness, light gave them the feeling of safety and security. Over time, people recognized how useful it was to be able to carry on with their daytime activities after nightfall and started to use artificial sources of light. As an example petroleum lamps were used on a daily basis until the invention of artificial light produced by electricity, which gave a jump-start for the use of outdoor lighting. Outdoor lighting provides better visibility but its overuse does more harm than good. Gradually, electricity reached most parts of the world, although developing countries were and are still behind developed countries in terms of consumption of electricity. However, according to a research carried out recently by GFZ German Research Centre for Geosciences, the increase of light pollution was the greatest in developing countries between 2012 and Satellite data showed that the Earth s artificially lit outdoor surface at night grew by about 2 percent annually in brightness and area, which means a total of 8% increase from 2012 to 2016, which is a rate faster than what scientists had anticipated. As mentioned before, the growth in night-time light reached its peak in areas such as Africa and Asia. The reason behind that is that these nations managed to achieve improvements concerning infrastructure only decades later than developed countries. Only in already bright countries did the light remain stable, including the world s brightest countries such as Italy, the Netherlands and the United States of America. The war-torn parts of Syria were the only regions where night-time light declined. This research was published in Science Magazine and indicates that light pollution really is an urging problem on both national and international level. Preserving nature and the environment while not going below our basic standards is a goal that can be accomplished only through international cooperation and worldwide solutions. The mission of the United Nations Environmental Programme at BIMUN 2018 is to seek long-term solutions that can be achieved and applied on a global scale.

4 The Effects of Light Pollution on Humans Medical research suggests that light pollution and excessive light exposure have a harmful impact on our health. Missing the dark might be the cause for a variety of diseases in the society. One of the main effects of extreme exposure to artificial light is partial disabilities in visibility. Disability glare causes us to avert our eyes from the veil of light being scattered across our retinas. Such quick adjustments are overly tiring for the eyes, especially for the elderly, whose eyes are much worse in adjusting to strong and sudden illuminations. In addition, one may suffer in some kind of sleep disorder caused by poor production of the melatonin hormone, which is released by darkness and inhibited by light and is primarily responsible for regulating the daily cycles of our systemic activities. Again, this is an example of artificial light intervening in the natural day and night pattern. It is also believed that people are at a higher risk for certain types of cancer due to being exposed to extreme light, but this statement has not been proved yet. How does it affect the Environment? Ecological light pollution poses a serious threat in particular to nocturnal wildlife. Half of all the life on Earth start their daily activities at sundown. Nocturnal animals sleep during the day and are active at night, but their natural, balanced night-time environment is altered by turning night into day, due to extreme light exposure. It can cause confusion in animal navigation, because predators are adapted to hunting at night, while prey animals use darkness to cover and hide from their natural enemies. Artificial light reduces their time for certain biological processes such as looking for food, seeking shelter and finding mates to reproduce. This is a serious and harmful intervention in the rhythm of nature by humanity, which not only affects current generations of animals, but will also cause long-term disturbance. It might even result in the extinction of certain nocturnal species. Animals living in areas which are situated near towns and big cities are at an even greater risk of being disturbed, since the sky glow can be hundreds or even a thousand times brighter over urban areas. For the same melatonin suppression problems we have with lights at night, creates similar problems in animals. Secondly, the other highly-affected species are sea turtles. They live in the ocean but hatch at night on the seaside. Hatchlings find their way to the oceans guided by the bright horizon above the water, but artificial lights from nearby cities and resorts often deter them from their goal, thus causing the death of millions of hatchlings annually. A research led by Tessa Mazor, a Ph.D. candidate at the University of Queensland shows that sea turtles nest on seashores and they return to the same nesting coasts where they were born, often within 10 km of their hatching site. Moving such distances exposes sea turtles to vast amounts of danger ranging from being hunted by predators to going the wrong way due to disturbance caused by ecological light pollution. However, sea turtles are not the only maritime creatures affected.

5 Light pollution around lakes prevents certain kinds of zooplanktons from eating surface algae causing algal blooms. Algal bloom is the phenomenon when surface algae in lakes and oceans is not eaten by planktons and therefore the vegetation is killed due to lack of light available for photosynthesis. Thirdly, light pollution has a huge and serious impact on nocturnal bird migration. Many species of birds, especially small insectivores migrate at night. These birds will use the light from the Moon and stars and the setting Sun for navigation during their bi-annual migrations, but their natural navigation aid is hidden by sky glow and the over-illumination of urban areas. Artificial light draws night-migrating birds toward brightly-lit buildings in cities thus putting them at a risk of not finding shelter and food. Research groups observed that once birds fly through a lit environment, they ll return to that lit source and then hesitate to leave it, and in doing so, become trapped in cities that offer little food for them. They also often crash into brightly-lit skyscrapers and buildings of broadcast companies, or just circle around them until they fall to their death from over exhaustion. It is clear that many different species of animals are threatened by light pollution, and this threat can only be reduced through international cooperation. Artificial light sources indeed contribute to our well-being and they make our lives much more comfortable, but we still must not forget about the nature around us and the harm we do to it as we use electricity and artificial light excessively. The question we need to consider is that do we really need all those shiny, spectacular buildings and commercial panels? We also may want to consider taking a more active role on a global scale in actions such as the Earth Hour. Although it is mainly aimed at reducing electricity consumption, it does contribute to decreasing light pollution all over the world.

6 Useful Links and Sources File/01_lightpollution.pdf globe Should you have any questions, do not hesitate to contact us at Please also submit your position papers of about words to the same address by March 18th.