BEIJING • The air quality in Beijing deteriorated to the worst in a year-and-a-half yesterday, with the authorities forecasting it would be at least another day before conditions improve.
Levels of the most hazardous, tiny particulate matter - known as PM2.5, which can lodge deep in a person's lungs - soared to 288 as of noon in the Chinese capital, according to data published by the US Embassy in Beijing.
That is 11 times higher than what the World Health Organisation says is the average level of healthy exposure in a 24-hour period.
It is also higher than PM2.5 levels recorded in several Californian cities where the air has been affected by local wildfires. The reading was 188 in Sacramento and 164 in San Francisco as of 11am Beijing time, the US government's AirNow website showed.
Beijing's PM2.5 level went down to 229 in the early evening.
The city's pollution levels, though high yesterday, are still significantly below heights reached earlier in the decade. The gauge reached 761 on March 22, 2010, before a government campaign to curb pollution by cutting down on the use of coal and fuel oil.
Officials are particularly focused on improving air quality in the winter heating season, which runs from November through March, when energy demand is at its peak.
PM2.5 level in Beijing yesterday, 11 times higher than the average level of healthy exposure in a 24-hour period, according to the World Health Organisation.
Many Beijing residents responded by posting pictures on social media with the tag "gone are the buildings", a practice that has spread as the air worsens during the winter. Some areas of Beijing and nearby Hebei province experienced visibility of less than 50m.
"The only motivation to go to work this morning is that my office has a much better ventilation system and hundreds of air purifiers to ensure the air quality is better than at home," quipped one person on social media.
Mr Chai Fahe, deputy director of the National Joint Research Centre on Air Pollution Causes and Control, said weak wind from the south and high humidity in the region are to blame for the heavy smog. Cold fronts were expected to gradually clear the smog.
BLOOMBERG, CHINA DAILY/ASIA NEWS NETWORK