On January 27, 2013, smog was widespread over 1 million square kilometers in the mid eastern area of China. For the first time, China’s Central Meteorological Station issued a smog alert (blue level), which is separate from a fog alert. Visibility on some sections of road in Beijing was under 500 meters. The air quality across Beijing was in a state of “serious pollution.”
Source: Reprint from Beijing News by China Gate, January 28, 2013
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