In the 1940s and 1950s, many Western countries encountered air pollution thanks to decades of industrialization and modernization. In some notorious air pollution incidents – most notably the Meuse River Valley smog in Belgium in 1930, the Donora smog in Pennsylvania in 1948 and the smog in London in 1952 – many people died, leading to the promulgation of anti-pollution laws in those countries.

It wasn't until the 1980s that air quality in those countries was restored.

China's GDP expanded from about 365 billion yuan ($58.8 billion) in 1978 to 57 trillion yuan in 2013, making the country the world's second-largest economy. Behind the exponential expansion of economic output, however, is the lack of consciousness in protection of the environment and economical use of energy and resources, leading to problems ranging from serious air pollution to disappearance of rivers.

Admittedly, as its economy expanded at a fast pace, China has drafted a number of environmental protection laws and regulations. But they have either lacked teeth or have not been implemented seriously as policymakers have put economic growth at the top of their agenda.

Things are changing for the better in recent years, with environment protection laws becoming more forceful and implementation stricter. Based on Western experiences, if the trend can be continued, hopefully it may take 20 or 30 years for China to stop the environmental degradation and, in the best scenario, restore clean air, fresh water and fertile farm land.

The headwinds remain strong. As efforts to protect the environment and restructure the economy by lowering the weight of pollutant-producing industries are set to cost growth, it is tough for policymakers across the board to sincerely embrace the green drive, especially at a time when the economy is slowing and risks continuing to slow.

But if we do not seriously carry out our environmental protection and restructuring agenda, we will have to suffer from more smog if nature does not give us more wind. It is highly precarious for us to build our smog-eliminating drive on the favors of nature.