- All living beings on Earth are adapted to the natural rhythm of light and darkness. Some have chosen dawn, some day, twilight or night for their activities, and any disturbance of this daily cycle of light brings greater or lesser inconvenience. In the everyday circumstances of our lives, we rarely think about this, and even fewer are aware of the problems of unwanted nocturnal light or light pollution.
- The first to loudly point out this problem were astronomers, for whom the white and orange haze from artificial lighting prevents them from observing the night sky. This is supported by satellite images of light islands above the most densely populated parts of Europe, North America, and Asia.
- Light pollution is any emission of artificial light outside the zone or object that needs to be illuminated, which affects the ecosystem and human health and creates unnecessary energy losses and costs. The causes are excessive use of light, improper placement of lighting fixtures, and lighting fixtures
It is designed in such a way that light scatters in all directions, rather than being directed only at the surface that needs to be illuminated.
Lights pollution threatens the life cycles of plants and animals, and one of the most well-known examples is its impact on the migratory routes of birds. Strong spotlights or tall brightly lit skyscrapers in global megalopolises disorient birds, causing them to deviate from their migratory paths and ultimately die before reaching their final destinations. To prevent these undesired consequences, some Western cities have implemented a prohibition on the nighttime illumination of tall buildings during migration periods.
Light pollution also affects urban songbirds such as warblers, nightingales, and blackbirds, which start singing unnaturally early in the night. This extends their feeding time, leads to earlier hatching of chicks, and ultimately affects the migration rhythm.
Sea turtles lay their eggs on sandy beaches, from which the hatchlings emerge in the nighttime, relying on them as a safe orientation point. However, light pollution can confuse the hatchlings and disrupt their ability to find their way to the sea. This has negative consequences for their survival and population stability. The moonlight reflects on the surface of the water and serves as a guide to the sea for them. However, strong artificial light from the coast causes disorientation and a large number of newly hatched turtles do not find their way to the sea.
For amphibians, excessive lighting causes changes in the secretion of melatonin, a hormone that regulates photophysiological processes and behavior. By illuminating shallows, the spawning grounds of certain fish species are endangered, whose life cycle, and thus the population size, is linked to the coast.
Among insects, the most well-known example is the firefly; excessive lighting disrupts the communication between males and females, which takes place through light signals, causing them to gradually leave the area where they inhabit or die out.
In the world of plants, the influence of “extended days” is observed in the delay of winter dormancy, and the phenomenon that increased sources of light energy together with changes in seasonal temperatures cause their premature “awakening” in spring.
We humans are also not immune to the influence of light pollution. R Medical research results confirm that excessive artificial light energy and the resulting disruption of the day-night rhythm reduce human resistance and lead to immune and hormonal disorders that can cause various diseases.
In developed Western countries, an increasing number of cities are introducing measures to protect against light pollution, such as reducing nighttime lighting where possible or replacing so-called standard lighting fixtures with environmentally-friendly ones. Because, one thing we all agree on, we all need the darkness of night. It preserves our health and maintains the balance of nature’s ecosystem.