Blue skies in Beijing have become an increasingly common sight, a far cry from the days when roads had to be closed and planes grounded because of severe smog..
Blue skies in Beijing have become an increasingly common sight, a far cry from the days when roads had to be closed and planes grounded because of severe smog.
The striking change stems from China’s efforts to fight air pollution, a fight that has brought about a drastic nationwide decrease in PM2.5 particulates – pollutants so fine they can enter a person’s lungs and bloodstream.
But a new study by American and Chinese researchers has shown that China’s progress in cleaning up its air might not be all it is made out to be, throwing up lessons for other cities battling smog.
The study, published in the Proceedings of the National Academy of Sciences journal in the United States earlier this month, was carried out by Harvard University’s John A. Paulson School of Engineering and Applied Sciences and Nanjing University of Information Science and Technology.
It showed that even as PM2.5 levels plunged by as much as 40 per cent, ground-level ozone has spiked.
Researchers say there is a causeand- effect link between the two.
