China's dramatic decrease of particulate matter has triggered a rise in ground-level ozone pollution.
China has managed to reduce levels of fine particulate matter emissions by roughly 40 percent in just four years.
However, research from Harvard's School of Engineering and Applied Sciences and the Nanjing University of Information Science and Technology shows this quick fall has triggered a rise in ground-level ozone pollution.
According to the paper published in PNAS, researchers studied roughly 1,000 sites in China over the past five years. Their findings showed an increase of surface ozone levels in urban clusters of China, particularly Beijing and Shanghai.
According to the Environmental Protection Agency, ground-level ozone is one of the main components of smog.
Ground-level ozone is created by chemical reactions between oxides of nitrogen, known as NOX, and volatile organic compounds, or VOCs, under the presence of heat and sunlight.
The study indicates that particulate matter, known as PM 2.5, acts as an absorbing agent of the radicals that make up ozone pollution.
Its sharp decrease has left more radicals available to generate ground-level ozone. Researchers said in an article on the Harvard school's website that "extra efforts are needed to reduce NOx and VOC emissions in order to stem the tide of ozone pollution."
According to the U.S. Centers for Disease Control and Prevention, ground-level ozone is linked to aggravation of pulmonary diseases, lung and throat irritation, and higher probabilities of contracting a respiratory illness. (Next Animation via Reuters)
|Shanghai Financial Center and modern skyscraper city in misty gold lighting sunrise behind pollution haze, view from the bund in Shanghai, China. GettyimagesBank|