This August, as southwestern Sichuan province grappled with widespread power outages, Shanghai — which gets a significant percentage of its energy from Sichuan hydroelectric dams — temporarily shut down the extravagant show that illuminates the Lujiazui financial district and the Bund every night. For locals tired of the bright lights, the dark Huangpu Riverbank was a welcome respite. It also offered a rare glimpse of a Chinese nightscape, untouched by the city government’s obsession with lighting.
Urban lighting is typically classified into two types. Functional lighting primarily meets the practical needs of city dwellers at night, while landscape lighting serves to beautify the nighttime cityscape. The current boom in landscape lighting originated in the northeastern coastal city of Dalian, which began installing newer and more powerful lights along streets and public squares in the early 2000s as part of a public safety and tourism initiative. Other cities soon followed suit, eventually sparking an arms race. Buildings were covered in blinking LED lights, and cities lit up their streets like nightclubs.
There weren’t any lights that were too bright, too colorful, or too spasmodic. Light shows have been set up along waterfronts, in central business districts and even in residential areas. More recently, cities have started adding elaborate drone performances to the night sky during the holidays. Behind all these shows were grandiose promises of luring tourists and transforming office centers – traditionally dead at night – into vibrant landmarks.
Left: The Lujiazui financial district during the drought in Sichuan, August 2022. By Tik Tok user @Shawan.Wang; Right: A night view of the district, 2014. VCG
But this urban lighting explosion has unforeseeable negative effects on urban landscapes, ecological balance, astronomical observations and road safety.
Light is an intense stimulus and light shows often rely on bright, high-intensity, high-saturation, and high-contrast light. In 2019, longtime lighting expert Hao Luoxi compiled ample evidence to show how nighttime lighting suppresses melatonin secretion, disrupts sleep and circadian rhythms, lowers immunity, and even causes emotional problems. Hao’s article cited a study by Japanese and Chinese scholars on lighting in six commercial zones in Shanghai and Hong Kong, with a total of 888 measurement points. The team found that 47% and 86% of measured circadian stimulation (CS) levels in the two cities, respectively, exceeded the working threshold for acute melatonin suppression.
Excessive lighting harms not only humans but also wildlife. For example, birds use natural light at night to navigate and can only make out approximate route information. When confronted with artificial light, they find it difficult to see buildings and other obstacles; They might even fly in the opposite direction to avoid lit areas or collide with other flying animals. One of the leading causes of death for North American migratory birds is collision with tall buildings, and many of these collisions are related to night lights.
Similar tragedies have happened in China. In August 2006, hundreds of birds died at a ferry crossing in Dalian after the installation of 14 excessively bright light poles. In a 2009 paper on the ecological impact of nocturnal lighting at Beijing’s Summer Palace, researchers found that swifts were particularly sensitive to unusual external light stimuli at night, and were easily startled from their nests. Likewise, a 2012 study found that artificial nighttime lighting can disrupt the daily biorhythms of the Siberian rubythroat during migration.
The effect of lighting is not limited to birds. Overlighting can make it more difficult for female turtles to lay eggs and nest, as well as exacerbate the risk of hatching and reduce the hatchlings’ chances of survival. It can also cause insects to congregate around the lights until they die of exhaustion, reducing insect populations and disrupting the food chain.
There are signs that city planners are finally seeing light in darker skies. In its technical report “CIE 234: 2019: A Guide to Urban Lighting Masterplanning”, the International Commission on Illumination (CIE) explicitly included stray light as an important control component in urban lighting planning. In China, there were calls within the government to rethink and act. At the central level, a 2019 government document called for the “special rectification” of vanity projects or politicized projects, including over-the-top landscape lighting schemes. At the local level, the eastern city of Hangzhou specifically emphasized the importance of a “dark sky” in its 2013 lighting plan and proposed the establishment of a “night reserve” free from light pollution. Just a month before the lights along the Huangpu River were turned off, Shanghai revised its environmental protection to add language about preventing light pollution.
Progress has stalled. Hangzhou, for example, has been torn between residents’ desire to turn off unnecessary lighting at historic scenic spots like West Lake, and the city’s desire to boost its “soft energy” through social media-friendly lighting projects.
The question of how to effectively enforce lighting regulations will remain as long as city governments continue to view nighttime landscape lighting, including garish light shows, as a beautification rather than pollution. But theatrical light shows shouldn’t be the norm in cities, nor should buildings serve as big screens for cheesy advertising. Instead of emphasizing the personality of different cities, the proliferation of landscape lighting has homogenized each city. Let us let our cities lighten and darken with grace.
Translator: Katherine Tse; Editors: Cai Yineng and Kilian O’Donnell; Portrait artist: Wang Zhenhao.
(Cover photo: A view of the Lujiazui financial district, without the light show, Shanghai, August 2022. By Tik Tok user @Shawan.Wang)