A dense fog, reducing visibility to under 500 meters in some places, hit China's capital Beijing yesterday, causing flight cancellations and the closing of several sections of highway, Beijing Daily Messenger reports today.

Visibility began falling from 5:00 PM yesterday until 6:40 PM, 16 flights in Beijing Capital International Airport were delayed, and 9 were canceled. The airport quickly activated rapid response measures, informing passengers of the weather and flight schedules. Additional staff members were drafted in to appease and serve the stranded passengers.

Beijing Meteorological Bureau issued a Yellow Alert for heavy fog at 7: 40 PM. Street lamps were tuned on 20 minutes ahead of scheduled time. Information from the Beijing Traffic Management Bureau headquarters showed that traffic flow on the city's ring roads, trunk roads and liaison roads was within normal parameters. For safety concerns, traffic authorities shut the bidirectional Beijing-Tianjin-Tangshan Highway from 11:00 AM yesterday, before further closing the Beijing-Shenyang and Beijing-Shijiazhuang Highways from 4:10 PM. Road information was also quickly displayed through outdoor electronic screens.

"The fog will drop away today," a meteorological expert predicted, "A moderate north wind will sweep Beijing today and blow away the vapor gathered above the city."

Beijing's air quality was the day before yesterday, rising to slightly polluted, and yesterday to Grade 4 of moderate heavy pollution, for the first time this month. Experts from the Beijing Environmental Protection Bureau said pollutant discharges and emissions in Beijing were relatively high and vulnerable due to the meteorological conditions.

Meteorologists said crowds of middle and high clouds gathered above Beijing in recent days. Bad air flow and the low diffusivity of the pollutants caused the dense fog.

As of yesterday, the number of days with an air quality index equal or higher than grade II has reached 230, eight days away from Bejing's goal of 238 this year.

(China.org.cn by Zhang Yunxing December 12, 2006)