Does China Have an Ozone Problem?

China suffers from greater and more frequent concentrations of ozone in its airwaves than any other country with similar ozone monitoring capabilities, a recent study has found. Published in the journal Environmental Science and Technology Letters, the paper examines Chinese concentrations of ozone and the frequency of days which exceed recommended guidelines and compares them to other countries around the world.

The results reveal that humans, animals and plants in China are exposed to dangerous levels of ozone between two and six more times than in Europe, Japan, South Korea or the United States of America. The news is a blow to Chinese aspirations to shed its ignominious reputation as one of the world’s most polluted countries and strike out towards a greener tomorrow.

Chinese progress compromised by ozone

For decades, China has endured terrible levels of air quality and suffered a reputation as one of the most polluted places on the planet. As recently as 2011, the country’s power plants produced as much nitrogen oxides (NOx) as all the passenger vehicles in the world cumulatively. This led to grave implications for the health of China’s 1.38 billion people and regular red alerts for its biggest cities.

Concerned about the problem, the Chinese government entered a new era in air quality monitoring in 2013 and implemented its Action Plan on Air Pollution Prevention and Control (APAPPC) the same year. Since then, concentrations of major air pollutants like particulate matter 2.5 (PM2.5) have fallen by an average of 35% across 74 of its biggest urban metropoles.

Unfortunately, the same can’t be said for ozone. This invisible contaminant can be in abundance even on days with crystal clear blue skies and has such has flown under the radar somewhat. Moreover, Chinese policy has tended to focus on the wintry haze of pollution and smog which congregates in the colder months, while ozone is at its worst in summer.

New study quantifies the extent of the problem

Prior to 2012, there was a real scarcity of ozone monitoring stations in China. Thanks to the launch of the APAPPC the following year, the country now has access to substantial amounts of data about the contaminant’s presence, though until now a comprehensive study on ozone had not been carried out.

The latest study compiled data collected from 1,600 ozone monitors across the country over the last five years to gain an insight into how ozone concentrations have been affected in that time. In contrast to other pollutants, the levels of ozone in Chinese air has actually increased year-on-year since 2013. Perhaps more concerningly, these concentrations are far in excess of what is found in other countries with comparable monitoring capabilities.

The total number of days in which average ozone concentrations exceeded the daily “safe” limit of 70 parts per billion in China was over 60. That’s around twice as many as experienced in nearby Japan and South Korea, four times as many as the States and six times more than Europe. Indeed, present-day levels of ozone in many Chinese urban centres are comparable to those found in US and European cities in the 1980s and 90s, signalling that China still has a long way to go in terms of achieving satisfactory air quality across the board.