Urban Smog and Environmental Information 2010–2015
By the early 2010s, urban air pollution had become one of China’s most visible environmental problems. Rapid growth in coal consumption, vehicle ownership, construction, and heavy industry had produced frequent episodes of dense smog in major cities, especially across Beijing-Tianjin-Hebei and other heavily industrialised regions.
What changed during this period was not simply the severity of pollution, but the way it was measured and communicated. Earlier air-quality reporting focused mainly on pollutants such as PM10, sulphur dioxide, and nitrogen dioxide. Fine particulate matter, or PM2.5, was not yet part of the national ambient-air standard, even though it posed significant health risks and had become central to public concern.
In 2012, China revised its national ambient-air-quality standards to include PM2.5 for the first time and introduced a new Air Quality Index system. Monitoring was then expanded in stages across major cities. Air pollution increasingly became something residents could follow through daily numerical readings rather than simply judge by whether the sky looked hazy.
By 2013, severe regional smog had pushed air pollution to the centre of national environmental policy. The government moved beyond monitoring toward restructuring coal use, industrial production, transport, and urban energy systems.
Policy Response
2012 — Ambient Air Quality Standards
“环境空气质量标准”
China revised the national ambient-air-quality standard to include PM2.5 and an eight-hour ozone standard, while tightening several existing pollutant limits. The revised standard also expanded automatic monitoring requirements and was implemented progressively across Chinese cities.
Official English source:
https://english.mee.gov.cn/Resources/standards/Air_Environment/quality_standard1/201605/t20160511_337502.shtml
2012 — Technical Regulation on Ambient Air Quality Index
“环境空气质量指数（AQI）技术规定”
The new AQI system translated concentrations of major air pollutants, including PM2.5, into a common public-facing index. This made daily air quality easier to communicate and compare across cities.
Official English background:
https://english.mee.gov.cn/Ministers/Speeches/201203/t20120308_224409.shtml
2013 — Air Pollution Prevention and Control Action Plan
“大气污染防治行动计划”
The State Council launched a national action plan aimed at reducing heavy smog and improving urban air quality. The plan introduced differentiated regional targets, with PM2.5 reductions of approximately 25% in Beijing-Tianjin-Hebei, 20% in the Yangtze River Delta, and 15% in the Pearl River Delta by 2017 compared with 2012 levels.
It also targeted coal consumption, small coal-fired boilers, outdated industrial capacity, vehicle emissions, and heavily polluting industries.
Official English source:
https://english.mee.gov.cn/News_service/infocus/201309/t20130924_260707.htm
2013 — Expansion of PM2.5 Monitoring
Following the new standard, China expanded PM2.5 monitoring from an initial group of major cities to additional prefecture-level cities and key regions. Monitoring, early-warning systems, and public reporting became part of the national air-pollution strategy.
Official English source:
https://english.mee.gov.cn/Ministers/Activities/201309/t20130902_259357.shtml
Under the Dome by Chai Jing Is Removed from Major Platforms
2015
On February 28, 2015, former CCTV journalist Chai Jing released Under the Dome, a self-funded documentary on China’s air pollution crisis. Using interviews, government data, animations, and personal testimony, the film explained PM2.5, coal dependence, industrial emissions, and weaknesses in environmental enforcement.
The documentary spread extraordinarily quickly. It received more than 100 million views within its first 24 hours and more than 300 million views within days. It was initially promoted by major Chinese media outlets, including People’s Daily, and China’s newly appointed environment minister Chen Jining publicly praised the film for raising environmental awareness.
Within a week, however, the film disappeared from major Chinese video platforms, including Youku, Tencent, Sohu, and LeTV. The People’s Daily page that had carried the documentary was also removed. Reuters reported that the film had become inaccessible across China’s major video-sharing websites by March 7, while Chinese media coverage of the film had already begun to narrow.
The episode became a striking example of the tension between environmental transparency and control over public debate. The government was simultaneously promoting stronger action on air pollution while limiting the circulation of a documentary that had turned pollution into a national public conversation.
Selected Sources
‘Under the Dome’ Pollution Documentary Blocked on Chinese Websites”
South China Morning Post, March 7, 2015
“Controversial China Pollution Film Disappears from Video Sites”
Reuters, March 7, 2015