On December 7, 2015, Beijing, China, took the historic action of issuing a red alert for air pollution, the first time it had ever done so. The city was responding to a heavy smog event that was expected to last for several days, endangering the health of Beijing’s 23 million residents.
In 2013, China developed a four-step air smog grading system, increasing in severity from blue to yellow to orange to red. The system uses a number of criteria for judging severity, including visibility, humidity and the concentration of small particles, known as PM 2.5. PM 2.5 are combustion particles smaller than 2.5 microns in diameter, small enough to enter lungs and in some cases the blood stream. China also has a more general air-quality alert system that uses the concentration of major pollutants (sulphur dioxide, nitrogen dioxide, carbon monoxide and ozone) to create an AQI—air quality index.
The AQI on December 7 exceeded 450, prompting the first ever red alert. Levels of PM 2.5 also sky-rocketed. The World Health Organization considers PM 205 levels lower than 10 to be acceptable; the U.S. classifies PM 2.5 levels over 200 particles as “very unhealthy” and over 300 as “hazardous.” Concentrations in Beijing on December 7 reached 253, prompting the first ever red alert. Environmental groups have termed this and other serious air pollution events as “airpocalypses.”
A red alert requires schools to close and reduces car traffic by 50%, allowing only vehicles with even or odd license plates to drive. The alert lasted for several days, until weather conditions changed and disbursed the pollutants.
PM 2.5 concentrations in Beijing had exceeded those on December 7 many times in the past, but the government only issued orange alerts, the level below red. Observers suspected that this first red alert was a response to public pressure, as China and the world’s other nations were actively negotiating the Paris climate accords at the same time. Since then, Beijing has issued several other red alerts.
Air pollution in China is a major environmental issue in the world’s largest country. China produces more air pollution than any other nation, much of it the result of heavy industrial manufacturing and electricity generation that relies substantially on burning coal. The U.S. embassy in Beijing monitors air pollution at the embassy. From 2008 to 2015, the embassy recorded unhealthy, very unhealthy or hazardous air quality on two-thirds of all days; air quality was good on only 2% of days.
China continues to make major commitments to improving air quality. More than half of all new electricity generation in China is based on renewable energy; China installs new renewable energy at the highest level of any country in the world. Despite these actions, turning around the devastating air pollution in China’s main cities will take many decades.
BBC News. 2015. China pollution: First ever red alert in effect in Beijing. BBC News, 8 December 2015. Available at: http://www.bbc.com/news/world-asia-china-35026363. Accessed December 6, 2017.
Phillips, Tom. 2015. Beijing issues first pollution red alert as smog engulfs capital. The Guardian, 7 December 2015. Available at: https://www.theguardian.com/environment/2015/dec/07/beijing-pollution-red-alert-smog-engulfs-capital. Accessed December 6, 2017.
Wong, Edward. 2015. Beijing Issues Red Alert Over Air Pollution for the First Time. New York Times, Dec. 7, 2015. Available at: https://www.nytimes.com/2015/12/08/world/asia/beijing-pollution-red-alert.html. Accessed December 6, 2017.
Yaoti, Ren. 2016. A guide to China’s smog alert colors. GB Times, Jan. 15, 2016. Available at: https://gbtimes.com/guide-chinas-smog-alert-colours. Accessed December 6, 2017.