Shanghai's Pollution Problem: A City's Battle

Shanghai, like many large cities, struggles with air pollution. Since China's economic reform in 1979, the country has been the world's fastest-growing economy, and its cities have rapidly urbanized. Shanghai's air pollution stems from industrial blocks in suburban areas, human emissions, and natural sources. The city's pollution levels reached a peak in 2013, with dangerously high levels of fine particulate matter. While Shanghai has made significant progress in reducing air pollution in recent years, it still faces challenges in meeting international health standards.

Shanghai has fine particulate matter (PM2.5) levels above WHO health guidelines

Shanghai, like many large cities, has air pollution levels above the WHO's recommended guidelines. Fine particulate matter (PM2.5) is a major component of this pollution. PM2.5 is composed of liquid droplets and solid particles found in the air, often a result of human activity such as car emissions and coal burning.

Shanghai's air pollution levels have been a cause for concern for some time. NASA's Landsat satellites captured the expansion of the city between 2013 and 2017, during which there was a striking loss of greenery, mainly cropland. This was accompanied by degraded water quality, contaminated soil, insufficient housing and sanitation, traffic congestion, local climate alterations, and air pollution.

Shanghai's worst episode of air pollution was during the 2013 Eastern China smog, when dangerously high levels of fine particulate matter blanketed the city. Readings crossed the 300 µg/m3 mark on December 2, 2013, far exceeding the recommended WHO guideline of 10 µg/m3. This prompted the Chinese government to take action, and they unveiled the $284.2 billion “Airborne Pollution Prevention and Control Action Plan”, with a target to reduce PM2.5 in Greater Shanghai by 20%.

Shanghai has made significant progress in reducing air pollution since then. By 2016, the city had reduced air pollution by 26% compared to 2015 levels. In 2017, the local government released a master plan for 2040, calling for PM2.5 to be reduced to about 20 µg/m3. While the city has been exceeding targets, standing at an average of 35 µg/m3, this still remains above the recommended WHO guideline and harmful to health.

The main sources of PM2.5 in Shanghai are industrial blocks and vehicle emissions. Coal combustion was previously the worst source of pollution but has been reduced steadily over the years. Other pollutants in Shanghai's air include PM10 (respirable particulate matter), NO2 (nitrogen dioxide), SO2 (sulfur dioxide), CO (carbon monoxide), and O3 (ozone).

Shanghai's worst air pollution episode was during the 2013 Eastern China smog

Shanghai, China's largest city, has long experienced poor air quality compared to other megacities in North America and Western Europe. The city's air pollution can be traced back to China's economic reform in 1979, which saw the country become the world's fastest-growing economy. This rapid economic development came at the expense of environmental degradation.

The high levels of air pollution had a significant impact on public health. Studies have shown that day-to-day variations in ambient air pollution are positively associated with mortality and hospitalizations for cardiopulmonary diseases. During the 2013 Eastern China smog, authorities ordered children to stay indoors, pulled government vehicles off the road, and halted construction in an attempt to reduce the smog. Additionally, outpatient visits for coronary heart diseases (CHD) in a typical hospital in Shanghai were examined to understand the impact of the extreme air pollution event on cardiovascular health.

In recent years, Shanghai has made significant improvements in reducing air pollution. By 2016, the city had reduced air pollution by 26% below 2015 levels. These improvements can be attributed to emission control measures for industries, reductions in coal use, and cleaner car technologies. Despite these efforts, air pollution remains a challenge, and the city continues to exceed the recommended PM2.5 levels set by the WHO.

Shanghai's air pollution is caused by industrial blocks and car emissions

Shanghai, like many large cities, struggles with air pollution. This is mainly due to industrial emissions and vehicle exhaust, which are worsened by the dense traffic conditions in the city.

The combustion of gasoline or diesel fuel in vehicle engines produces a variety of harmful chemical emissions, including carbon monoxide (CO), nitrogen oxides (NOx), hydrocarbons (HC), volatile organic compounds (VOCs), and particulate matter (PM). Vehicle emissions are a significant source of air pollution in Shanghai, contributing to the formation of secondary pollution such as photochemical smog, visibility reduction, and haze. The annual average concentration of NO2 in the troposphere over China was much higher than that in the USA and most European countries in 2014.

To control air pollution from vehicle emissions, Shanghai implemented the "one car and one license number" policy in 2014. This policy aimed to control the number of vehicles by limiting auto licensing. As a result, there has been a gradual decrease in the number of ordinary cars and an increase in the proportion of new energy vehicles on the road. In addition, the city has been promoting the adoption of electric vehicles (EVs) to reduce emissions and improve air quality. Studies have shown that the health impacts of EVs are about 20 times lower than those of internal combustion engine vehicles (ICEVs).

Shanghai has also been working to reduce industrial emissions. Emission control measures for industry, combined with steady reductions in coal use, have helped the city make significant improvements in air quality. For example, between 1990 and 2017, the average PM2.5 exposure in China dropped by 9% from 57.8 to 52.7 µg/m3. However, it is important to note that even with these improvements, the PM2.5 levels in Shanghai still exceed the World Health Organization's guideline of 10 µg/m3.

Coal combustion was Shanghai's worst source of pollution in the 80s and 90s

Shanghai, like most large cities, has fine particulate matter (PM2.5) levels above WHO health guidelines. China's economic reform in 1979 kickstarted the country's rapid economic growth, with GDP growth averaging 9.5% through 2018. This economic growth was accompanied by accelerated urbanization, with the proportion of the urban population rising from 18% in 1978 to 59% in 2018. This urbanization came at the cost of environmental degradation, with NASA's Landsat satellites capturing the loss of greenery and the expansion of the Shanghai megalopolis.

In the 90s, regulatory bodies and a national air pollution monitoring system were implemented, but they failed to significantly improve air quality. Shanghai's air pollution problem persisted well into the 2010s, with the city experiencing dangerously high levels of fine particulate matter during the 2013 Eastern China smog episode. However, local authorities have made efforts to reduce air pollution in recent years, and by 2016, Shanghai had reduced air pollution by 26% below 2015 levels. These improvements can be attributed to emission control measures for industries, reductions in coal use, and the adoption of cleaner car technologies.

While Shanghai's air quality has improved, it still falls short of meeting the WHO guideline of 10 ?µg / m3, with the city's PM2.5 levels standing at an average of 35 ?µg / m3. The problem of air pollution in Shanghai is not unique, as most large cities in developing countries or highly urbanized areas face similar challenges. However, it is important to recognize that even fully developed countries struggle to eliminate air pollution entirely.

Environmental regulations in China seem to be less enforced post-COVID

Shanghai, China's largest and most populous city, has long struggled with air pollution. The city's rapid urbanisation and economic growth have come at an environmental cost, with fine particulate matter (PM2.5) levels well above World Health Organization (WHO) guidelines. While Shanghai has made notable progress in reducing air pollution in recent years, it continues to face significant challenges.

In the past, regulatory bodies, national air pollution monitoring systems, and pollution control research and development were implemented in China, but they failed to significantly improve air quality. The average PM2.5 exposure in China only dropped by 9% between 1990 and 2017, and Shanghai experienced its worst air pollution episode during the 2013 Eastern China smog.

Shanghai has since taken steps to improve its air quality, and by 2016, the city had reduced air pollution by 26% below 2015 levels. This was achieved through emission control measures for industries, reductions in coal use, and the adoption of cleaner car technologies. However, even with these improvements, Shanghai's air quality still falls short of international standards, with PM2.5 levels exceeding the recommended guidelines.

Post-COVID, the Chinese economy has faced challenges, and environmental regulations seem to have taken a back seat. While there has been a slight decline in emissions in recent years, driven by a shift towards renewable energy sources, the use of coal and natural gas in various industries continues to contribute to China's overall emissions. The environmental rebound effect post-pandemic has raised concerns, with a shift in priorities away from environmental protection and towards economic recovery.

Shanghai's air pollution is a complex issue with deep-rooted causes. While efforts have been made to improve air quality, the balance between economic development and environmental protection remains a challenge. As China navigates the post-COVID era, it is crucial to prioritise environmental regulations and sustainable practices to ensure a healthier future for its citizens.

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