Many Britons enjoy cycling to reduce car exhaust emissions
Recently, the PM2.5 levels in several cities across China have exceeded warning thresholds, with the most severely affected area being the Beijing-Tianjin-Hebei region, shrouded in smog and suffering from serious air pollution. In fact, countries with good air quality today have also experienced severe air pollution. So how did they manage to achieve blue skies and white clouds? What lessons can be learned?
The United Kingdom
The pain of pollution
"The Foggy City" — tens of thousands die from respiratory diseases
After the UK was among the first to undergo the Industrial Revolution, the London area became densely packed with factory chimneys that burned coal day and night, producing huge amounts of dust and toxic gases. This resulted in one-quarter of the year being shrouded in heavy fog, earning it the nickname "the Foggy City." In December 1952, large accumulations of carbon monoxide, sulfur dioxide, and dust within the fog led to 12,000 deaths from respiratory diseases within two months, with many more suffering from bronchitis, coronary heart disease, tuberculosis, and even cancer. This prompted the traditionally conservative British to resolve firmly and take action.
Measures: Bicycles replacing cars
In 1956, the UK enacted the Clean Air Act, which primarily aimed at reducing coal usage. To this end, the British government carried out large-scale renovations of traditional household stoves, implemented centralized heating in winter, and relocated major coal-consuming power plants and heavy industries to the suburbs. They also issued regulations requiring factories to build taller chimneys that met higher standards.
By the 1980s, the UK's focus in pollution control shifted to tackling vehicle exhaust emissions. The government mandated that all new vehicles must be equipped with catalytic converters to reduce nitrogen oxide emissions. They also imposed sky-high congestion charges and parking fees on private cars to curb car usage. At the same time, the government strongly promoted new energy vehicles, public transportation, and green transport. London planned to establish 25,000 electric vehicle charging points by 2015, with buyers of electric cars receiving substantial rebates, exemption from car carbon emission taxes, and even free parking. Bicycle transport was also prioritized by the government, with plans to build 12 bicycle superhighways. Senior British officials led by example in controlling the use of official vehicles. One day in 2009, Prime Minister David Cameron rode his bicycle to work, while Deputy Prime Minister Nick Clegg took the subway.
Measures: Green belts three times the size of the city
In addition, strengthening greening has been an important measure to combat air pollution. In densely populated London, the per capita green space reaches as high as 24 square meters, and large circular green belts have been established on the outskirts of the city, covering thousands of square kilometers—almost three times the size of the urban area. Today, the number of foggy days in London has decreased from 90 per year over 100 years ago to fewer than 10.
Measures: Pollution levels available via mobile phones
The UK government also emphasizes real-time reporting of air quality information to the public. The official website not only publishes real-time air quality data for Greater London and the hourly concentration and weekly trend charts of various pollutants but also has developed a special Google Earth layer. Once users download the relevant software, they can intuitively view the values and trends of all pollutants at monitoring sites across the UK. The public can access this information either through PCs or mobile applications.
The UK’s experience in pollution control to some extent represents the stance of European countries. For example, replacing car travel with bicycles has also been advocated and implemented in countries such as the Netherlands and Denmark.
The United States
The pain of pollution
Hundreds of elderly deaths in just a few days
As the most developed country, the US once suffered from severe air pollution due to industrial emissions and car exhaust. In the mid-20th century, the ozone concentration in the Los Angeles area was very high, and photochemical smog (a light blue smoke produced by the photolysis of pollutants) was a prominent issue. In 1952 and 1955, this resulted in tragic incidents where hundreds of elderly people died within just a few days.
Measures: Zonal management
The US adopted a regional environmental management framework, breaking state boundaries and dividing the nation into ten major geographic regions based on geography and socio-economic factors. Regional offices were established to implement unified management. Environmental agencies had the authority to legislate, enforce laws, impose penalties, and coordinate efforts through a combination of mandatory measures, monitoring, and technological improvements. For instance, environmental authorities in the California area formulated and implemented air quality management plans, using tools such as emission permits, public information disclosure, and public participation to promote emission reductions, eventually reducing ozone concentrations in Los Angeles in the 1980s.
In 1990, amendments to the Clean Air Act were passed. At the same time, states with severe ozone pollution jointly established the "Ozone Transport Commission," setting relevant emission reduction standards and overseeing their implementation. These efforts covered more than 20 US states and eastern provinces of Canada, achieving significant results.
Measures: Real-time monitoring of fine particles
In 1997, based on the Clean Air Act, the US Environmental Protection Agency (EPA) established specific standards for PM2.5 levels in the atmosphere to better detect these previously overlooked fine particles. The US focuses on strict monitoring, real-time disclosure, and legislative regulation for PM2.5 management.
They have set up thousands of particulate matter monitoring stations nationwide. The EPA’s official website informs the public of measured air quality indexes, with PM2.5 parameters updated hourly. To make it more intuitive, the website typically uses six colors to indicate air pollution levels. Green means “good,” followed by yellow, orange, red, purple, with maroon indicating “hazardous.” The public can also request the EPA to send air quality information for specified areas via email.
Measures: Exercise advice for the public
When pollution is relatively severe, the US official website advises the public to control the intensity and duration of outdoor activities to reduce health risks. Additionally, the media advises people not to exercise near busy roads, not to smoke indoors, and to reduce the use of candles and wood-burning stoves to control indoor pollution.
The Philippines
The pain of pollution
2,000 people die from pollution every year
More than 2,000 people in the Philippines die from air pollution each year, and its capital, Manila, is one of the most air-polluted cities in Asia. Vehicle exhaust is the main culprit, accounting for 80% of the air pollution.
Measures: The government launches a "people's war"
Due to the large urban population and chaotic management, the authorities lack sufficient technical equipment and manpower to monitor and regulate vehicle exhaust emissions. Under these circumstances, the government was forced to launch a "people's war."
On one hand, they widely publicized the threats of vehicle exhaust to the environment and human health. On the other hand, they launched an SMS platform, calling on tech-savvy young people to report vehicles with excessive emissions via text messages. Once a vehicle is reported by five or more people, traffic authorities will test it and order rectification within a set period. Of course, this reporting system can only treat the symptoms. The Philippine government has also invested in equipping Metro Manila with natural gas-powered vehicles and building natural gas refueling stations. Tax and loan incentives are provided for natural gas vehicles.
Japan
The pain of pollution
A surge in respiratory diseases
In the early stages of industrialization, Japan also suffered greatly from pollution. Among the "Eight Great Pollution Disasters of the World," four occurred in Japan during the 1950s and 1960s. One of them was in 1961, when Yokkaichi City experienced severe air pollution due to emissions from oil refining and industrial fuel, leading to a sharp increase in respiratory diseases among residents, especially a significant rise in asthma cases. Tokyo, one of the world’s largest metropolises, was also shrouded in smog and had foul-smelling rivers in the 1960s.
Measures: New buildings must have green spaces
In the 1980s, Japan began to tackle pollution through multiple channels, placing great emphasis on the environment and achieving miraculous results on its small, densely populated land. One of Japan’s pollution control methods was urban greening. Authorities in Tokyo mandated that new buildings must include green spaces and rooftop gardens. Tokyo’s greening efforts rarely involve grass but focus on planting trees, not only aiming for green coverage but also green volume. The air-purifying effect of numerous trees in the city is naturally significant.
Measures: Lawsuits lead to legislation
Another method was controlling vehicles, which was tied to a long-running lawsuit. In 1999, over 600 respiratory disease patients along Tokyo’s national highways collectively sued local governments and seven diesel car manufacturers, claiming that vehicle exhaust had harmed their health. Expert verification confirmed that PM2.5 from vehicle exhaust is highly carcinogenic.
As a result, in 2003, Tokyo introduced new legislation requiring vehicles to be equipped with filters and banning diesel engine vehicles from entering the city. On the first day of the new regulation, traffic police conducted thorough inspections at major intersections inside and outside Tokyo. Drivers were asked to start their engines, and a white towel was placed over the exhaust pipe. If the towel turned black, the vehicle was not allowed into Tokyo. Five years later, the lawsuit concluded, and the defendant car companies paid 1.2 billion yen to settle with 633 plaintiffs.
Today, all cars manufactured in Japan come equipped with filters, meeting Euro III emission standards. Tens of thousands of taxis in Tokyo run on natural gas. These efforts have made Tokyo’s skies blue and visibility clear. Even meticulous Japanese people compare it to rural areas, saying Tokyo’s air quality still isn’t good enough. Yang Yi J172
Annual PM2.5 standards around the world
Region PM2.5 (micrograms/cubic meter)
Canada, many parts of Australia Below 5
USA, many parts of Russia Between 5–15
Central and South American countries Mostly between 5–15, some regions 15–20
UK, Germany, France, Spain Between 5–20, with London at 15
Italy Southern regions 10, northern regions 30
Japan, North Korea, South Korea 10–20
Singapore 2–18
Experience in managing pollution in major foreign cities shows that to truly tackle PM2.5, efforts must focus on two aspects: strengthening the management of PM2.5 sources by reducing demand for fossil fuels, and tightening emission controls to strictly limit total discharge. Managing PM2.5 is a systematic project that requires mobilizing the strength of the entire society and finding a governance path suited to the urban socio-economic and geographical environment.