Environmentalists and biologists have long warned that artificial light at night can have adverse effects on human and terrestrial wildlife. Disrupts sleep, feeding and reproductive cycles.
British server Good contact analyzed the average number of hours of daylight, the level of light pollution and the level of brightness of artificial lights.
Based on this, he compiled a list of the brightest cities in the world. In this ranking, Prague ended up as the eighth darkest city in the world with an average of 4.5 hours of sunlight per day and light pollution of 5.21 mcd / m2.
The brightest city in the world is Riyadh, Saudi Arabia.
The most populous capital of the kingdom lies in the middle of the Nafud Desert – vast sandy plains covering 103,600 square kilometers. This Middle Eastern city is experiencing long, hot and bright summers, which contrast with the short winter season. With an average of more than eight hours of sunlight a day, Riyadh is naturally one of the brightest cities on the planet.
The Russian capital is famous for its Christmas lights and is the second brightest city in the world. Although Moscow has an average of only five hours of daylight, the city is lit by a lot of artificial lighting. Its light pollution is just over 20mcd / m2, which is the most on the FGC list.
The US capital Washington is in third place. With an average of almost seven hours of sunlight a day, the city is naturally lit. During Christmas, the city is illuminated by a wide range of light decorations. For the rest of the year, 75,000 street lights provide a lasting glow over the city.
London’s location among the world’s brightest cities is quite surprising given that England is often associated with cloudy skies, rain and short summers.
The South American metropolis of red wine and steaks is also the fifth brightest city on the planet. Buenos Aires has an average of about seven hours of sunlight a day, but the city is covered with artificial lighting.
The most luminous cities
|Capital, country||Average hours of daylight||Clarity (mcd / m²)||Artificial lighting (μcd / m²)||Light score / 10|
|1) Riyadh, Saudi Arabia||8.84||18.90||18 700||7.11|
|2) Moscow, Russia||5.21||20.30||20 200||6.50|
|3) Washington, DC, United States||6.93||17.80||17 700||6.13|
|4) London, United Kingdom||4.47||11.40||11 200||5.87|
|5) Buenos Aires, Argentina||6.92||12.40||12 200||4.79|
|6) Athens, Greece||7.60||10.30||10 200||4.58|
|7) Dubai, United Arab Emirates||9.61||4.30||4 130||4.46|
|8) Madrid, Spain||7.59||9.44||9 270||4.37|
|9) Lisbon, Portugal||7.69||9.22||9 050||4.37|
|10) Tokyo, Japan||5.14||9.34||9 170||4.32|
|11) Rome, Italy||6.78||10.20||10,000||4.22|
|12) Singapore, Singapore||5.54||11.60||11 400||4.17|
|13) Santiago, Chile||7.69||8.10||7 930||4.03|
|14) New Delhi, India||7.36||8.49||8 320||4.00|
|15) Cape Town, South Africa||8.48||6.42||6 250||3.93|
|16) Jakarta, Indonesia||8.17||6.69||6 520||3.88|
|17) Beijing, China||7.32||7.35||7 180||3.71|
|18) Bangkok, Thailand||7.19||7.26||7 090||3.67|
|19) Paris, France||4.55||9.66||9 490||3.66|
|20) Seoul, South Korea||5.66||9.52||9 350||3.64|
A growing body of research shows that marine life is also sensitive to artificial light, especially the spectrum of blue and green light. Now, for the first time, scientists have quantified the rate of underwater light in coastal zones around the world. A team of researchers from England, Norway and Israel has published the first global atlas of artificial light at sea.
“These very low levels of light generated by artificial light are critical to biological organisms,” said lead author and oceanographer Tim Smyth, who specializes in marine optics and remote ocean color sensing in Plymouth. Naval laboratory. “But the impact it has on the marine environment has not been sufficiently explored.”
Earth at night seen from the International Space Station. Time-lapse images courtesy of the Earth Science and Remote Sensing Unit, NASA Johnson Space Center.
– Outer Space (@SpaceUniverseg) February 1, 2022
The darkest cities in the world
Bogotá, Colombia, has ended up as the darkest city in the world, with an average of just over 3.5 hours of sunlight a day. Its light pollution is less than three mcd / m2.
It is no big surprise that the second darkest city in the world is the island of Reykjavík. Although they experience the famous “noon” period, when the sun can last up to 22 hours and never set completely, the long and dark island winter months mean that Reykjavik has on average less than four hours of sunlight a day. Iceland is also one of the countries with the lowest levels of artificial lighting.
3. Luxembourg, Luxembourg
Luxembourg, nestled between France, Germany and Belgium, became the third darkest city in the world. The Luxembourg capital has an average of only five hours of sunlight a day and there is also little street lighting.