Light pollution: who does it harm and what you can do about it

light pollution it is an ecological problem which, unlike plastic pollution or the effects of climate-altering gases, is rarely discussed in public.

The constant illumination of the sky by artificial light sources not only has a negative effect on numerous animals and plants, but also can alter the human biorhythm.

What is light pollution?

The term “light pollution” describes permanent lighting at night by artificial light sources and the associated effects on us and the environment.

Street lamps, neon signs, and night lighting of public buildings also contribute to the phenomenon, like the lighting of private houses, gardens and balconies.

In cities, the clearest symptom of light pollution is that you cannot see the stars in the sky. Beyond that, however, our tendency to turn night into day has much more serious repercussions.

Consequences of light pollution

For millions of years, life on earth was determined by the day-night rhythm. Consequently, the life of the animal and plant worlds adapted to the natural phases of light and darkness that change throughout the year.

For a relatively short period of time, we have broken the cycle with artificial light sources, with consequences that are hardly noticeable at first glance, but can sometimes be serious.

1. For people

Humans belong to the diurnal creatures and we need the night to rest and regenerate. Constant lighting disrupts the natural day-night rhythm and causes, among other things, disturbances in the production of the hormone melatonin, which controls the rhythm of sleep and numerous physiological processes that occur during the night. The alteration of this cycle increases the risk of obesity, metabolic disorders and hormone-dependent cancers, among other diseases. Similar effects can be observed in many animals.

On the other hand, there are the more subtle effects of light pollution: if we stop seeing the stars in the sky, our relationship with the environment changes. The vision of the stars (and of the planets, shooting stars and the path of the Milky Way) development has shaped our image of our place in the cosmos, it has made us recognize its immensity and magnificence. Star blindness makes us more lonely and isolated from our natural environment. That is why UNESCO declared the starry sky as a World Heritage Site in 2008.

Moreover, night lighting it is a waste of energy and money, and reveals our little environmental awareness.

2. For the birds

Migratory birds that follow the stars on their way to their winter quarters are distracted by night light sources and may lose orientation. Artificial light also has a negative effect on the rhythm of life of birds.

Songbirds begin to sing earlier in the day. Breeding and mating behavior changes, and their sleep is affected.

3. For insects

Approximately half of the native insects are nocturnal. To perform their important ecological task as pollinators and to feed and reproduce, they depend on natural darkness.

Instead of being protected by starlight, they are attracted to lamps and other sources of night light and die of exhaustion or are easy prey for predators.

Light pollution is one of several factors that they contribute to increased insect mortality and the general decline of biodiversity.

4. For plants

Even plants react to artificial light with changes in their life cycle and, for example, they begin to form leaves and flower earlier under artificial light.

The trees of the city illuminated by streetlights delay leaf fall in autumn a natural response to lower temperatures that protects them from damage caused by frost.

On the other hand, in meadows lit at night, the plants produce fewer flowers and consequently fewer seeds. A circumstance that in turn can affect their reproduction and pollinating insects.

These are just a few examples that show how massive and diverse the effects of artificial lighting are across the ecosystem. Many consequences of light pollution have not yet been adequately investigated. and the interactions, for example, between animal and plant life are so complex that the effects can hardly be assessed.

Light pollution map

light pollution maps show the severity of light pollution in your region and around the world) and in which countries the problem is increasing or decreasing.

For example, through www.lightpollutionmap.info you can see the light sources. You can also see it in Earth at night, made with data from NASA, where the intensity of light is displayed as a relief.

In these maps it can be seen that Spain is the second country in Europe that emits the most light into the sky and where there is a greater expenditure on public lighting per inhabitant. Are you willing to keep paying to light up the dark?

Measures against light pollution

Many measures, such as reducing public lighting or dispensing with outdoor advertising at night, etc., can only be carried out by society as a whole. However, each and every one of us can contribute to reducing light pollution in everyday life, For example, with these simple tips:

Refrain from permanent lighting outdoor. Do not turn on external lights in your house.Choose lighting with switch, motion detector or timer and only turn it on when you really need light.Reduces stray light upwards outdoors, for example, using lamps with cover.Install exterior lighting as low as possible, to attract fewer insects and birds.Bet on a soft and warm light (maximum 2,700 Kelvin and low lumen values). It is better to use several weak lamps than one bright oneAvoid artificial lighting as much as possible on the outskirts of towns and in nature reserves.Write to your town hall requesting the change of streetlights that emit light upwards or that are more intense than necessary.