Apparently Earth is losing its darkness. Researchers say artificially lit surfaces around the world are spreading and growing brighter, producing more light pollution at night.
Light pollution, also known as photo pollution, is the presence of anthropogenic and artificial light in the night environment.
As a major side-effect of urbanisation, it is blamed for compromising health, disrupting ecosystems and spoiling aesthetic environments.
“We are convinced that artificial light is an environmental pollutant with ecological and evolutionary implications for many organisms – from bacteria to mammals, including us humans – and may reshape entire social ecological systems,” says Franz Holker of the Leibniz-Institute of Freshwater Ecology and Inland Fisheries.
Thanks to electric lights, outdoor lighting grew at a rate of three per cent to 6pc annually in the second half of the 20th century. While this has benefited human productivity and safety, it has come with a dark side: The night is no longer dark enough.
“Half of Europe and a quarter of North America have experienced seriously modified light-dark cycles,” say researchers.
This light pollution can have serious consequences for living things, which have evolved in accordance with a natural day-night cycle, where the only major sources of light at night would have been the moon or more intermittent sources such as volcanoes, lightning, wildfires or auroras.
“From an evolutionary perspective, now, artificial light at night is a very new stressor. The problem is that light has been introduced in places, times and intensities at which it does not naturally occur, and many organisms have had no chance to adapt to this new stressor,” says Holker.
Scientists say this is a big problem, given that 30pc of vertebrates and more than 60pc of invertebrates are nocturnal.
It can affect plants and even microbes. It also could be harming vital interactions between species, such as the pollination of plants and spreading of seeds by key nocturnal creatures.
We humans are impacted by artificial light too, because there are certain physiological processes that happen during the day and certain ones that happen at night and they often work against each other.
Also think about it the more light pollution there is, the fewer stars we can see, which makes it difficult for astronomers to study the heavens with ground-based telescopes.
To find out whether the human demand for light is still on the rise or levelling off, researchers studied data from the month of October in each year from 2012 to 2016.
They found that over that time, Earth’s artificially lit outdoor surface grew by 2.2pc each year and the total radiance grew by 1.8pc per year. On top of that, the outdoor areas that already had been lit when the study started in 2012 also brightened by 2.2pc per year.
The fastest growth took place in countries in developing regions, such as Asia, Africa and South America. Countries that already were brightly lit, such as America and Spain, appeared stable. A small number of war-ravaged countries such as Yemen and Syria saw a drop in their artificially lit levels.
Researchers had long suspected that the introduction of LEDs would mean less energy used for lighting. The problem is this also made lighting cheaper.
“Whenever you make lights more efficient, you just don’t save energy. What happens instead is that people put more lights up,” say researchers.
Electric lights may have revolutionised our lives, but as illumination increases, the toll on wildlife and human health is becoming harder to ignore.
So basically our nights are getting brighter, due to cheaper artificial lights and once again earth is paying the price!
Reem Antoon is a former GDN news editor. She can be reached on: firstname.lastname@example.org