How climate change complicates China’s ‘battle for blue skies’

Air pollution in China rebounds as economic activity picks up, while climate change is bringing new challenges for air quality management
<p>A hazy day in Beijing, March 2023. Despite China&#8217;s progress on improving air quality, 99.9% of the population lives in areas where the air quality is deemed unsafe by the World Health Organisation. Globally, the figure is 99%. (Image: Andy Wong / Alamy)</p>

A hazy day in Beijing, March 2023. Despite China’s progress on improving air quality, 99.9% of the population lives in areas where the air quality is deemed unsafe by the World Health Organisation. Globally, the figure is 99%. (Image: Andy Wong / Alamy)

Air pollution levels in China fell a “remarkable” 42.3% between 2013 and 2021, according to this year’s Air Quality Life Index from the University of Chicago’s Energy Policy Institute (EPIC).

The report found that, if sustained, this pollution reduction will extend the average Chinese citizen’s life expectancy by 2.2 years. “That is outstanding, rapid progress over a single decade,” Christa Hasenkopf, director of air quality programmes at EPIC, told China Dialogue.

Autumn 2013 was a turning point for air pollution in China, when the State Council released its “Air pollution prevention and control action plan”. The following year, then-premier Li Keqiang told the National People’s Congress: “We must be as resolute in the war on pollution as we are in the war on poverty”. In 2018, the action plan was succeeded by the “Three-year plan on defending the blue sky”, which brought more cities under air quality management targets.

The progress on air pollution is well illustrated by the Beijing-Tianjin-Hebei region, which has been China’s most polluted since 1998. Between 2013 and 2021, control measures achieved a 53% drop in airborne particulate concentrations. Following such success, the region’s leading group on air pollution control was disbanded in October this year.

Curbing air pollution remains a daunting challenge

While China has made rapid progress over the past decade, the Air Quality Life Index still rates its air quality as 13th-worst in the world. The annual average concentration of PM2.5 (particulate matter less than 2.5 microns wide) in China is six times the World Health Organisation (WHO) guideline of five micrograms per cubic metre. Only 0.1% of China’s population lives in areas where this guideline is not exceeded.

Particulate pollution is now the fifth-biggest factor limiting life expectancy in China, after cardiovascular disease, tumours, high blood pressure and tobacco. The index notes that even though China’s own particulate pollution standard is relatively weak (35 micrograms per cubic metre), around 30% of the population lives in areas where this is not met either. Life expectancy would increase by six months in those areas if air pollution was brought within national standards. Reducing air pollution to the WHO guideline across the whole country would increase China’s average life expectancy by 2.5 years.

At a recent conference, the Ministry of Ecology and Environment (MEE) revealed that air quality in nearly a third of China’s cities fell short of standards at the end of 2022. In general, pollutant emissions are still high and air quality continues to depend heavily on pollution dispersing in the atmosphere.

As the Air Quality Life Index states: “Despite China’s progress in reducing pollution, more progress is necessary to reach the air pollution concentrations that the WHO considers a safe level.”

Pollution rebounds amid economic recovery

It is yet to be seen if China built upon its air-quality improvements during 2023, a year in which pressure for steady economic growth has grown. The government has refocused on economic development since adjusting its Covid response measures at the end of last year, which is often at odds with efforts to combat air pollution.

On 20 February, inspection teams headed by the environment minister Huang Runqiu descended unannounced on seven businesses in the Henan cities of Pingdingshan and Xuchang. These visits were prompted by a protracted haze event that had affected much of southern Henan since the turn of the year. Problems identified by inspectors included: improper operation of pollution-management installations; emissions exceeding standards; failure to implement emergency emissions-abatement measures during heavy pollution conditions; and falsified production and monitoring data.

At a regular MEE press briefing in March, Liu Bingjiang, director of the ministry’s department of atmospheric environment, outlined the factors that have increased air pollution: the resumption of typical transit levels since Covid measures were relaxed; modernisation projects in the steel, aluminium, cement and glass manufacturing sectors; and the launching of new “high energy, high pollution” programmes by local governments that are primarily designed to boost economies, without adequate environmental considerations.

Chinese worker processes steel parts at the plant of Shandong Iron Steel Group
Processing steel at a factory in Laiwu, Shandong province. State-mandated expansion of polluting industries like steel and cement, intended to stimulate local economies, has resulted in an uptick in air pollution this year (Image: Alamy)

According to MEE data for January to September this year, the national average PM2.5 concentration was 28 micrograms per cubic metre, up 3.7% year-on-year. The average PM10 concentration was 51 micrograms per cubic metre, up 6.2%.

China Dialogue spoke to Ruan Qingyuan, who leads the air quality programme for the non-profit Institute of Public and Environmental Affairs (IPE) in Beijing. Ruan believes the main reason for this year’s rebound in air pollution is that control measures have been cancelled out by the recovery of social and economic activity.

“The pandemic had a huge impact on social and economic activity in China over the past three years, so there has indeed been a rebound in pollution compared with last year in many cities,” said Ruan. “If we compare with the same period in 2019, however, there has actually been a drop in PM2.5 concentrations.”

MEE data confirms this: China’s average PM2.5 concentration between January and September was down 17.6% on the same period in 2019.

“I think China remains as determined to manage air pollution this year as in the past decade, and overall environmental quality continues moving in the right direction,” Ruan said.

Ruan explained that much work has been done in recent years to fine-tune pollutant management in many parts of the country. This has included grading different industries to better target emitters with customised regulatory approaches. These grades consider the industry processes, the level of an emitter’s pollution, and the related control measures being taking.

New challenges posed by climate change

The marginal gains made by the end-of-pipe treatment of pollutants are diminishing, however, as the management of air pollution enters a new phase. “The downward curve in pollutant concentrations of the past few years is less steep than it was, and it’s getting harder to prise the next microgram of reduction,” said Ruan.

The effects of climate change are worsening these challenges by adding air pollutants and weakening the necessary conditions for the atmosphere to disperse them.

‘Atmospheric stagnation’?

When low wind speeds at ground level cause air pollutants to concentrate in an area. Over time, it can lead to haze.

Northern China was hit by a series of sandstorms this spring, causing pollution levels to rise off the scale; the increased frequency of sandstorms is inextricably linked with desertification in Mongolia, which is driven by climate change.

Regarding pollution dispersion, climate change will likely mean more frequent atmospheric stagnation in China. This phenomenon, characterised by low wind speeds near ground level, hinders the diffusion of pollutants. Over time atmospheric stagnation can give rise to haze conditions.

A study from Tsinghua University considered future atmospheric stagnation events in China under a “medium-emissions” scenario (carbon emissions peak around the year 2040 and the average global temperature rise likely exceeds 2C by the end of the century). In this case, China’s average number of atmospheric stagnation days between 2046 and 2050 would be 57.4 per year. Between 2006 and 2010, it was 54. The biggest increases would take place in China’s north-east, northern Inner Mongolia, the North China Plain and the Sichuan Basin.

If pollutant emissions in China remain at current levels, the number of winter days with PM2.5 concentrations above 150 micrograms per cubic metre (heavy pollution) and 250 micrograms (severe pollution) in 74 key cities will increase by 1.8 and 1.1 days respectively. This would primarily be due to atmospheric stagnation events becoming more common.

Pollution by particulate matter is not the only concern. Comparing the same 2006 to 2010 and 2046 to 2050 periods, the Tsinghua study predicts climate change will increase heatwave days in the 74 cities from 2.7 to 8.8 per year. This will make urban ozone pollution more frequent: the number of summer days when maximum one-hour ozone concentrations exceed national standards will increase by 3.8 days per year.

The overall situation is not optimistic
Ruan Qingyuan, Beijing-based Institute of Public and Environmental Affairs

Moreover, around 14% of those high-ozone days will occur during heatwaves when high temperatures contribute to the photochemical reactions that give rise to ozone. This “climate penalty” reflects the amplifying effect of climate change on ozone production at ground level. It will exacerbate ozone pollution events and bring adverse health effects for hundreds of millions of people.

As the authors of the Tsinghua study state: “Managing air quality in China will become more challenging under a changing climate.”

Ruan Qingyuan said: “Effort has gone into managing ozone continuously in the past few years in China, but the overall situation is not optimistic. Climate change will indeed bring new challenges to the managing of ozone in the future.”

“There are several ways in which the climate could make air pollution worse,” added Christa Hasenkopf, “from increased ozone levels, to increased wildfires producing PM2.5 pollution, to worse health outcomes when high temperatures and high PM2.5 levels combine. These reasons provide even more incentive toward lowering our carbon emissions as soon as possible.”

Next steps: structural transformation and market trading?

As well as mitigating climate change, cutting carbon emissions also reduces air pollutant emissions. Li Gao, director of the MEE’s climate change response department, pointed out in 2018 that China’s energy consumption is dominated by coal, which is its main source of air pollution. In terms of targets and approaches, he noted synergies between managing air pollution and dealing with climate change.

In 2020, Xi Jinping announced China’s dual goals of carbon-peaking before 2030 and carbon neutrality before 2060. For Ruan, realising this would enable China to more effectively reduce pollution at source, via the necessary transformation of electricity generation and industrial production.

The “Synergetic road map for carbon neutrality and clean air in China” was released earlier this year, co-sponsored by five organisations including Tsinghua University. It notes the benefits of jointly reducing greenhouse gas and air pollutant emissions: if China reaches peak carbon by 2030, it can expect to reduce major air pollutant emissions by more than a third of current levels. The proportion of Chinese cities meeting air quality standards would rise to more than 80%.

“With the ‘dual carbon’ goals leading the way, I believe there will be added momentum in the future for further reducing pollutant emissions at a deep level,” said Ruan.

Hasenkopf suggests establishing a trading market for air pollutant emissions, inspired by China’s carbon market, which promotes reductions by issuing firms with emission quotas that they can trade. In her view, China is still over-reliant on administrative orders for cutting pollution that impose significant social and economic costs. “It is an open question on whether or not political appetite will be maintained for using those same measures to further ratchet down air pollution,” she said.

A regional trading market for air pollutant emissions in India is a testament to the feasibility of this concept. In an effort to curb particulate pollution in the industrial city of Surat, the Gujarat state government set up the world’s first emissions trading market for particulate pollution in 2019. Michael Greenstone, the director of EPIC, told Indian media in 2022 that participating factories had reduced their emissions by 24%, with little cost to industry.

“China maintains the world’s largest national carbon market, which could also position the country well for the adoption of more market-based approaches for further improving air quality,” said Hasenkopf. “Air pollution-based markets could more efficiently and sustainably reduce pollution at a lower cost than previous command-and-control style policies.”