China’s air quality has been particularly bad so far this winter. Severe smog or haze episodes have occurred one after another with short breaks in between, affecting many parts of the world’s second largest economy, including some remote cities in the far west Xinjiang Uyghur Autonomous Region. Northern China has been hit hardest, with much of the national and international attention focusing in the Beijing-Tianjin-Hebei region.
Last week, Beijing issued its first-ever red alert for “fog” due to extremely low visibility caused by haze. The warning is the most severe pollution warning in the country’s four-tier system, resulting in school closures and flight cancellations and delays.
Haze and PM2.5 are perhaps the most commonly used words in China nowadays. PM2.5 is a term for tiny particles that can cause respiratory, cardiovascular, reproductive, and other health problems. High concentrations of agglomerated fine particles in the atmosphere are directly translated to decreased visibility or grey-ish sky. Hence, China counts the number of blue-sky days per year to assess progress made toward improved air quality.
Since China’s Premier Li Keqiang declared a war on air pollution in 2014, the Chinese Government released a set of aggressive air quality control regulations that aimed to reduce PM2.5 by 20% in five years. Annual average concentrations of PM2.5 have declined in the last three years. And this past summer, Beijing and other cities in China had more “blue sky” days than previous years. China’s government was pleased to see the effectiveness of its stricter emission standards on power plants and industrial facilities, but that sentiment quickly changed when a series of negative reports of haze emerged in the Fall of 2016.
It is, of course, convenient to blame the weather. No one knows better than Beijing residents about the importance of having northerly wind or a good rain to clean a sky filled with PM2.5 and gaseous pollutants. It is true that the atmospheric conditions, with less precipitation and wind, are less favorable for pollutant dispersion in the winter than in the summer in the Beijing-Tianjin-Hebei region. This is an important contributor to worsened air quality in winter months in this region. However, this factor alone does not explain the frequent reoccurrence and very wide spread of haze episodes across China. Blaming weather for the problem may exasperate an already angry audience who might consider this an irresponsible excuse to the real cause of the problem.
The reality is that new regulations to curb pollution aren’t enough, and the latest alert signals that China’s government needs to do more. The January 4th 2017 issue of The Economist presented data showing a hike in production output of crude steel, cement, and coke in the Beijing-Tianjin-Hebei region in the second half of 2016 compared to the same time period in 2015. The question remains whether the more stringent emission controls of these large industrial facilities are enough to offset the emissions resulting from increased industrial production.
As China’s economy grows in tandem with growing demands for energy, coal is still unfortunately the principal fuel for keeping homes and buildings warm in many parts of China beyond Beijing. Small-scale coal boilers and residential coal stoves in general have very poor combustion efficiency, emitting PM2.5, carbon monoxide, and other pollutants into the atmosphere, which can be visually seen as soot-laden smoke. These numerous and individually-owned combustion devices are hard to regulate for their emissions. In addition, as China continues to experience growth in the number of privately-owned automobiles, there is every reason to believe that vehicular emissions have contributed to the air pollution problem as residents drive more.
Qualifying contributions of various sources to each haze episode has never been easy. While scientists are busy figuring out how water vapours from combustion sources, including natural gas and petroleum combustions, enhance the formation of PM2.5 and how emission-altered climate and weather conditions can in turn affect air quality, the message for policy actions is clear. It is a burning issue! Burning coal and other fossil fuels is the origin of the problem. There is a limit on how far today’s technology can go in terms of reducing emissions from coal. Without a significant reduction in coal consumption, especially when atmospheric conditions are unfavourable for pollutant dispersion, it would not be possible to see blue skies.
Although China has been increasingly investing in the production of renewable energy and cleaner energy, this winter’s severe haze problem sends a strong signal that the pace for replacing dirty energy is not fast enough. If all the efforts were targeted to large industrial facilities while leaving numerous small sources unchecked, one could only just sit and wait for mother nature’s power to blow away or wash out the dirty stuff pumped into the atmosphere by burning dirty fuels. China’s haze is truly a burning “burning issue.” Every effort should be made to reduce the burning of dirty fuels.
Junfeng “Jim” Zhang is professor of Global and Environmental Health at Duke University and Duke Kunshan University. He is also a visiting professor at Peking University.