17: Urban Air Pollution

Air pollution chokes many Chinese cities. Soot and haze levels exceed national and international health standards, often greatly, although air quality has improved in many Chinese cities in recent years. 1

Most Chinese policies to help fight urban air pollution also help fight climate change. This chapter provides background on urban air pollution in China, summarizes the principal policies to address it and considers the impact of those policies on climate change.


The primary air pollutant in China’s urban areas is particulate matter. Fine particulates known as PM2.5 (particles smaller than 2.5 microns in diameter) are a significant problem. PM2.5 has a negative impact on human health due to its ability to penetrate lung tissue, enter the bloodstream and accumulate in the central nervous system. It can cause acute health problems on high pollution days as well as chronic cardiovascular and neurological diseases that can develop years after exposure to polluted conditions. 2

PM2.5 comes from many sources, especially heavy industry, coal burning for heating, vehicle emissions, power plant smokestack emissions, crop burning and fertilizers. A large fraction of China’s PM2.5 comes from secondary formation of particulates from precursor pollutants such as nitrates, sulfates, volatile organic compounds, ammonia and elemental carbon (dust). During haze events (extended periods of high ambient PM2.5 covering vast regions), stagnant air and air inversion conditions in the North China Plain can lead to rapid increases in secondary PM2.5 formation from these precursor chemicals.3

Regional transport of air pollutants is a significant factor in air pollution in many Chinese cities. During periods of severe haze, regional transport often accounts for a large fraction of ambient PM2.5. As a result, preventing haze requires regional coordination, not just local emissions reductions.4

Urban air pollution worsened significantly in many parts of China during the first part of this century. From 2001 to 2007, areas with 92% of China’s population experienced sharply negative air quality trends. According to satellite data, very few urban areas met national air quality standards. A long period of especially severe air pollution in the winter of 2013 gained widespread attention and became known as the Airpocalypse. 5

These trends reversed in 2013/2014. Since then, almost 80% of China has experienced air quality improvement. The proportion of cities achieving national air quality standards for PM2.5 has increased notably, particularly in eastern and southern regions. 6 PM2.5 concentrations decreased from 66 micrograms/m3 in 2013 in the Beijing–Tianjin–Hebei region to 41 micrograms/m3 in 2018. A similar improvement took place in the Sichuan Basin and Shanghai Yangtze River Delta regions. On a national average basis, PM2.5 concentrations fell from 55 micrograms/m3 in 2013 to 31 micrograms/m3 in 2018. 7

In 2019, researchers at Tsinghua University found that meteorological conditions were responsible for only 16% of the improvement in air quality in the Beijing–Tianjin–Hebei region and played no role in improvements in other air quality control regions. Policies to control air pollution were a more significant factor. Of the policy actions taken, the most important were those that addressed industrial emissions, including the enforcement of stricter emissions standards and closure of inefficient industrial boilers. Changes to residential heating or vehicle emissions were minor factors. 8

Researchers at Tsinghua and the Beijing Environmental Bureau found that, between 2013 and 2017, local emissions reductions accounted for 65% of improved air quality and regional reductions accounted for 22%. Coal boiler controls, cleaner residential heating, closure of local emissions-intensive industry and vehicle emissions controls contributed to local emissions reductions (in that order). 9 Other researchers have found that favorable weather accounted for 14% of the improvement in air quality in Beijing and up to 27% in Sichuan from 2013 to 2018. 10

Air quality policies have focused on the largest emitting sectors, particularly coal combustion in heavy industry and electricity generation. Sulfur emissions have seen the strongest reductions, which led to a decrease in severe haze events caused by formation of secondary PM2.5 during periods of high humidity. 11 Nitrogen and ammonia have seen smaller emissions reductions. As coal power and industrial emissions have fallen, the contribution of coal heating, vehicle tailpipe emissions (particularly diesel trucks) and agriculture has grown. 12

During the first months of the COVID-19 pandemic in early 2020, nationwide transportation restrictions and work closures resulted in significant improvements in China’s air quality—although a few weather-related haze events took place during this period. 13 NO2 emissions, which are mainly associated with heavy industry, fell 36% from the prior year during the lockdown period. However, NO2 emissions levels returned back to normal levels by the end of March 2020. 14

The health consequences of China’s air pollution are significant. Studies have found that:

  • air pollution contributes to 1.6 million premature deaths per year in China; 15
  • roughly 500 million residents of northern China have lost more than 2.5 billion years of life expectancy due to air pollution from coal burning; 16
  • almost 100 million people in China suffer from chronic obstructive pulmonary disease, and air pollution is one of the main causes; 17
  • deaths from cardiovascular and pulmonary disease in 272 Chinese cities are closely related to PM2.5 levels in those cities; 18 and
  • PM2.5 and ozone emissions from six sectors in China cause roughly 1.1 million premature deaths and cost approximately RMB 267 billion (roughly $38 billion) per year. 19

In recent decades, air pollution has been a top concern of many Chinese citizens. In a 2016 survey of Beijing residents, 96% said that poor air quality had negatively affected their health. In a 2015 national survey, 76% of respondents said that air pollution was a “big problem” and 35% of respondents said it was a “very big problem”. The air pollution documentary Under the Dome was viewed more than 300 million times in China before it was removed from Internet platforms four days after its 2015 release. 20

Figure 17-1: Beijing Hourly PM2.5 Readings – Annual Averages (2008-2021)

Source: U.S. Embassy, Beijing 21

Air Pollution Policies

Cutting air pollution is a long-standing goal of Chinese leaders. President Xi Jinping announced a Blue Skies Initiative shortly after coming into office in 2013 and spoke about the war against pollution in several high-profile settings in the 2010s, as did Premier Li Keqiang. 22 In recent years, President Xi and Premier Li have spoken less about air pollution, in part because the air pollution problem is not as dire as it was in 2013/2014 and in part because other issues including COVID, energy security, the economy and carbon neutrality have risen on the agenda.

China’s first air pollution law dates to 1987. In the decades that followed, China’s air pollution laws were mostly ineffective due to sporadic enforcement, low penalties and weak monitoring. Perhaps most important, local officials generally lacked incentives to make clean air a priority. Starting around 2007, the Chinese government developed and implemented serious measures to control air pollution in connection with the 2008 Beijing Summer Olympics. However, these measures affected only the Beijing area and were mostly short-term, such as shutting down factories before and during the Olympics. By 2009, air pollution in the Beijing area returned to its earlier high levels. 23

In September 2013, the Chinese government announced the Action Plan on Prevention and Control of Air Pollution, following the horrific air pollution events of the previous winter. The action plan called for a 10% cut in PM10 concentrations by 2017 in cities across China, with more stringent PM2.5 reduction targets in three key regions: a 25% reduction by 2017 for Beijing–Tianjin–Hebei, 20% reduction for the Yangtze River Delta and 15% reduction for the Pearl River Delta, with Beijing establishing a specific target to reduce average annual PM 2.5 concentrations to 60 ug/m3. It described 10 tasks for cleaning the air, including tightened enforcement, changes to the industrial and energy supply structure in key regions, strengthening enforcement, establishing regional coordination and setting up a public early warning system for pollution episodes. 24

Measures to control coal burning were a top priority. They included a ban on new coal-fired power capacity, improved SO2 and NOX controls at coal-fired power plants and policies to promote alternatives to coal (including natural gas, hydropower, wind power, solar power and nuclear power). Stricter vehicle fuel efficiency and emissions standards have also been adopted. The Chinese government has led campaigns against the use of fireworks during Spring Festival, a long-standing Chinese tradition, for air quality reasons.

Other changes include greater incentives for local officials to prioritize air quality, better air pollution monitoring, larger penalties and stricter enforcement. In 2014, Chinese authorities brought roughly 2000 criminal cases for environmental violations—double the number for the past 10 years combined. In November 2016, more than 1100 Chinese officials were held accountable for violations of air pollution laws. 25 In 2021, authorities issued 133,000 fines totaling RMB 11.6 billion, arrested 3397 people, closed 1093 polluting facilities and reported nearly 9000 property or asset seizures related to environmental enforcement. 26

China’s 13th Five-Year Plan (2016–2020) prioritized fighting air pollution. In addition to limits on coal consumption, the plan set quantitative goals for air pollution reduction and air quality, including a 15% cut in SO2 and NOx levels and a requirement that all cities meet air quality standards at least 80% of the time. Monitoring capabilities were enhanced dramatically, and each province was required to share air quality information regularly. 27 Figures published by the Ministry of Ecological Environment show that China met or exceeded the 13th Five-Year Plan targets. Between 2013 and 2017, the average concentration of PM2.5 fell 39.6% in Beijing–Tianjin–Hebei, 34.3% in the Yangtze River Delta and 27.7% in the Pearl River Delta. 28

During 2017, strict policies on coal burning, industrial activities and traffic were announced for the Beijing–Tianjin–Hebei area. These helped produce record cuts in pollution levels during the fall and winter of 2017–2018. However, natural gas supplies to replace coal in the region lagged, leading to shortages and inadequate heating during parts of the winter. 29

In June 2018, the State Council issued its Three-Year Action Plan for Blue Sky Defense. The Action Plan called for significantly reducing fine particulates and other air pollution with measures to control the production capacity of highly-polluting industries, promote clean heating and cut pollution from vehicles (including in particular heavy trucks). 30 It covered the greater Beijing¬–Tianjin–Hebei region (including Shandong and parts of Shanxi province), Yangtze River Delta and neighboring provinces, and the Fenwei Plain covering parts of Shanxi, Shaanxi and Henan provinces. The Action Plan set targets for reducing coal use, including a 10% reduction from 2015 levels by 2020 for Beijing, Tianjin, Hebei, Shandong and Henan, and a 5% reduction from 2015 levels by 2020 for the Yangtze River Delta. In 2021, the Action Plan was declared a success in all of its major goals. 31

To replace it, the government has announced a broader Three Landmark Campaign Program, covering air, water and soil quality. On air quality, the policy continues to emphasize the greater Beijing–Tianjin–Hebei and Fenwei Plain regions. Specific targets include reducing severe pollution days to below 1% of days by 2025, reducing NO2 and volatile organic compound emissions by 10% while reversing the growth trend of ground-level ozone, reducing diesel truck emissions by retiring old vehicles and shifting freight to railways and waterways, strictly preventing agricultural straw-burning and reducing ammonia emissions by 5%. 32 Individual cities also continue to adopt air quality plans and targets. For example, Shanghai has set a targets of an average PM2.5 concentration below 32 micrograms/m3 and more than 87% clear sky days in 2022. 33

In June 2022, five Chinese ministries, NDRC and the National Energy Administration issued the “Implementation Plan for Pollution and Carbon Reduction Coordinated Effectiveness,” emphasizing the importance of cross-ministry and cross-sector efforts to reduce air pollution and cut carbon dioxide emissions. 34 The Plan includes targets for reducing local air pollutants and carbon dioxide emissions, including increasing the share of steel produced with electric arc furnaces to 15% by 2025 and 20% by 2030, the share of renewable energy used in aluminum production to 30% by 2030, and the share of new energy vehicles in total sales for key air pollution regions to 50% by 2030.

Relationship to Climate Change

Most measures to fight urban air pollution in China also help fight climate change. Policies that promote solar, wind, hydro and nuclear power as alternatives to coal reduce both local air pollutants and heat-trapping gasses—as do policies that promote energy efficiency. Policies that promote energy efficiency and electrification (particularly from non-fossil sources) in Chinese industry, vehicles and buildings all have dual benefits, helping fight both local air pollution and climate change. 35

Policies that promote natural gas as an alternative to coal help reduce local air pollution by 90% or more, depending on the pollutant. The impact of those policies on climate change is more complicated.

  • Natural gas produces roughly half the carbon dioxide (CO2) emissions of coal per unit of energy. Converting China’s vast coal-based heating and power infrastructure to natural gas would significantly reduce Chinese CO2 emissions. 36
  • However, leaks during the production, distribution or consumption of natural gas could significantly reduce the climate change benefits of using natural gas to replace coal. Methane—the principal component of natural gas—is itself a powerful heat-trapping gas. As a rough rule of thumb, if more than 3–8% of the natural gas consumed as an energy source leaks, it cancels the climate change benefits of switching from coal to natural gas. 37 A 2021 study of China’s natural gas sources showed that the highest emissions sources (long-distance LNG) offered CO2 emissions intensities comparable to coal, with upstream and transportation emissions varying by a factor of six depending on the source. 38
  • In addition, new natural gas infrastructure, such as pipelines and receiving terminals, will likely last for decades. This infrastructure could slow the transition to even cleaner energy sources. There may be a trade-off between the CO2 emissions reductions natural gas can deliver by displacing coal today and the CO2 emissions reductions natural gas could delay by slowing the deployment of renewables and nuclear power in future years. 39 

China’s policies to promote electric vehicles provide significant local air pollution benefits, since electric vehicles do not have tailpipe emissions and the power to recharge them is usually generated outside urban centers. Electric vehicles in China also emit less CO2 on a lifecycle basis than similar vehicles with internal combustion engines. (Electric motors are far more efficient than internal combustion engines, offsetting the impact China’s coal-heavy electricity sector and upstream battery manufacturing emissions.) Continued improvements in EV efficiency and battery energy density, together with a growing share of low-carbon power in the electricity mix, are projected to increase the climate benefits of China’s EVs relative to conventional vehicles, even as the latter improve in fuel economy. Trends towards smart charging and aggregation of EV charging will also help reduce lifecycle CO2 emissions from electric vehicles, by shifting EV charging to off-peak times when carbon emissions are lower. 40

Finally, some technologies for controlling local air pollution are counterproductive when it comes to global warming. Scrubbers on coal plants have important local air pollution benefits, but increase CO2 emissions slightly since scrubbers require energy to operate. More significantly, synthetic natural gas can help reduce local air pollution by moving coal combustion from urban to rural areas but it significantly increases CO2 emissions. Policies to promote synthetic natural gas are counterproductive when it comes to China’s climate goals. 41


In Chinese: “空气末日.” Qingqing He et al., “Satellite-derived 1-km estimates and long-term trends of PM2.5 concentrations in China from 2000 to 2018,” Environment International (November 2021).
Qiang Zhang et al., “Drivers of improved PM2.5 air quality in China from 2013 to 2017,” Proceedings of the National Academies of Science (December 3, 2019).
Lauri Myllyvirta, “Analysis: Coronavirus temporarily reduced China’s CO2 emissions by a quarter,” Carbon Brief (February 19, 2020 and updated March 30, 2020).
Robert A. Rohde and Richard A. Muller, “Air Pollution in China: Mapping of Concentrations and Sources,” PLOS ONE (August 2015).
Yuyu Chen, Avraham Ebenstein, Michael Greenstone and Hongbin Li, “Evidence on the Impact of Sustained Exposure to Air Pollution on Life Expectancy from China’s Huai River Policy,” Proceedings of the National Academy of Sciences of the United States (August 2013).
Liwen Fang et al., “Chronic Obstructive Pulmonary Disease in China: a Nationwide Prevalence Study,” Lancet Respiratory Medicine (June 2018).
American Thoracic Society, “Chinese Air Pollution Linked to Respiratory and Cardiovascular Deaths,”, ScienceDaily (February 10, 2017); Yaohua Tian et al., “Fine Particulate Air Pollution and Hospital Visits for Asthma in Beijing, China,” Environmental Pollution (November 2017); Lei Zhao et al., “Association Between Air Pollution and Cardiovascular Mortality in China: a systematic review and meta-analysis,” Oncotarget (September 12, 2017).
Zhang, X, “The Reemerging Concern over Air Pollution in China: the Smog of the State’s Efforts to Guide Public Opinion,” Journal of Chinese Political Science (2018) at pp. 519–536; George Gao, “As Smog Hangs Over Beijing, Chinese Cite Air Pollution As Major Concern,”, Pew Research Center (December 2015). See also: Cunningham, Edward, Tony Saich and Jessie Turiel, “Understanding CCP Resilience: Surveying Chinese Public Opinion Through Time,” Ash Center for Democratic Governance and Innovation (2020); Li, X., & Tilt, B, “Public engagements with smog in urban China: Knowledge, trust, and action,” Environmental Science & Policy (2019) at pp.220–227; Associated Press, “As Incomes Rise in China, So Does Concern About Pollution,” (October 2016); Richard Wike and Bridget Parker, “Corruption, Pollution, Inequality Are Top Concerns in China,” Pew Research Center (September 2015).
U.S. Embassy, Beijing, data available for download.
President Xi spoke about air pollution at the 19th Party Congress in October 2017 and 13th National People’s Congress in March 2018). For remarks by Premier Li, see China Daily, “李克强对话夏季达沃斯论坛中外企业家代表 [Premier Li Keqiang’s Dialogues with Chinese and Foreign Entrepreneurs in Summer Davos Forum],” (in Chinese) (September 2013); ABC News, “China’s Premier Li Keqiang Vows to Tackle Chronic Air Pollution,” (March 2017); Ministry of Foreign Affairs, “Transcript of Premier Li Keqiang’s Meeting with the Press at the Fifth Session of the 12th National People’s Congress” (in Chinese) (March 2017).
Yana Jin, Henrik Andersson and Shiqiu Zhang, “Air Pollution Control Policies in China: A Retrospective and Prospect,” International Journal of Environment Research and Public Health (December 2016); Rob Schmitz, “China’s Fight for Cleaner Air,” Marketplace (July 2014); Colgate University, “The History of Air Pollution in China.”
China’s State Council, “National Action Plan on Prevention and Control of Air Pollution” (in Chinese) (2013).
Yana Jin, Henrik Andersson and Shiqiu Zhang, “Air Pollution Control Policies in China” (December 2016); China News, “环保部:2014年8458名环境案件犯罪嫌疑人被抓捕 [Ministry of Environmental Protection: 8458 Suspects Arrested in Environmental Criminal Actions in 2014],” (in Chinese) (June 2015); Christopher Beam, “China Tries a New Tactic to Combat Pollution: Transparency,” The New Yorker (February 2015).
NDRC, “13th Five Year Plan for Economic and Social Development of the People’s Republic of China” (2016) at pp.19 and 127; China’s State Council, “十三五”生态环境保护规划》主要内容 [Key Components of the Five-Year Plan for Nationwide Ecological Protection],” (2016); Barbara Finamore, “Tackling Pollution in China’s 13th Five Year Plan: Emphasis on Enforcement,” NRDC (March 2016); Beth Gardiner, “China’s Surprising Solutions to Clear Killer Air,” National Geographic (May 5, 2017); “Environmental Damages: 1,140 Chinese Officials Held Accountable,” China Daily (November 2017).
Ministry of Ecology and Environment, “Circular on the Final Assessment of the Implementation Plan of the Air Pollution Prevention Action Plan” (May 17, 2018); Chloe Wong, “Air Pollution in China: Are China’s Policies Working?,” Earth.org (December 23, 2021).
Damien Sharkov, “China Issues First National Smog Red Alert,” Newsweek (2017).
See Mark Dwortzan, “Tackling Air Pollution in China,” MIT News (May 2017).
Yue Qin, Ryan Edwards, Fan Tong and Denise L. Mauzerall, “Can Switching from Coal to Shale Gas Bring Net Carbon Reductions to China?,” ACS Publications (February 2017).
Methane breaks down more quickly than carbon dioxide in the atmosphere. Experts consider methane to be roughly 84 times more powerful than carbon dioxide as a heat-trapping gas over a 20-year period and 28 times more powerful over a 100-year period. See Intergovernmental Panel on Climate Change, Climate Change 2014: Synthesis, Fifth Assessment Report (2014) at p.87; Daniel Raimi, “The Fracking Debate,” Columbia University Press (2017) at p.111.
Yu Gan et al., “Carbon footprint of global natural gas supplies to China,” Nature Communications (2020).
China Automotive Technology & Research Center (CATARC), “中国汽车低碳行动计划研究报告2021 [China Automotive Low-Carbon Program 2021 Research Report],” (in Chinese) (2021); George Bieker, A global comparison of the life-cycle greenhouse gas emissions of combustion engine and electric passenger cars,” International Council on Clean Transportation (July 2021); Jiahui Chen et al., “Emission mitigation potential from coordinated charging schemes for future private electric vehicles,” Applied Energy (February 15, 2022). See Chapter 16 of this Guide.
Haijun Zhao, Weichun Ma, Hongjia Dong and Ping Jiang, “Analysis of Co-Effects on Air Pollutants and CO2 Emissions Generated by End-of-Pipe Measures of Pollution Control in China’s Coal-Fired Power Plants,” Sustainability (2017). See discussion in Chapter 14 of this Guide.

Guide to Chinese Climate Policy