Heavy Fog Normal Phenomenon This Season: Expert

Experts with the Central Meteorological Station said the heavy fog that blanketed north China including Beijing Thursday morning is a natural weather phenomenon in this season.

The heavy fog will gradually disperse starting from Friday afternoon, said the specialists.

Wednesday's Beijing was full of mild spring breeze and much sunshine.

According to the experts, the heavy fog has not only appeared in most areas of north China plain, but also in the southern tip of northeast China. Visibility in some areas of Beijing and Tianjin municipalities, and Hebei, Shandong and Henan provinces is just 500 meters.

The meteorological cloud chart also shows that the heavy fog weather have also occurred in areas like Siberia, said the experts.

The experts explained that at present, as the weather is becoming warmer in north China, coupled with more rainfall and bigger humidity of the air, it is prone to the formation of foggy weather when a slight drop in temperature is available.

In Beijing, it drizzled in some districts around eight o'clock in the morning. Last night, it blew northeastern wind, carrying warm, humid air current from Bohai Bay and Yellow Sea to north China, which has further increased the humidity in the air. So when the temperature went down at night, the condition for a heavy fog was ready, the experts noted.

Gong Xuezhong, a senior engineer with Beijing Municipal Meteorological Observatory, also held that heavy fog most easily occurs in Beijing in spring and autumn and the main reason behind the heavy fog is the result of suitable climatic conditions.

In the early hours of last night, Gong said it was clear with few clouds in Beijing and areas around it, and a drop in the temperature and the increase in humidity from radiation were obvious. But at that time, in the sky below 1,500 meters, a stronger, warm and humid air current slowly moved northwards, which has caused the humidity of the air in Beijing to reach saturation, resulting in the heavy fog Thursday morning.

Weather forecast from the China Central Meteorological Station predicted that there would be a cold air current from the northeast Friday afternoon, and with the wind, the heavy fog that blanketed Beijing would gradually disappear from south to north.

Fog Affects Traffic

A heavy fog that emerged at dawn Thursday has caused delays of air and highway traffic in north China and the southern tip of northeast China.

According to sources with the Beijing International Airport, visibility at the airport's runway was less than 300 meters early Thursday morning, far less than the sight range necessary for take- offs and landings.

As a result, by 9 a.m., 25 flights had been canceled, the airport sources said.

More than 5,000 air travelers are stranded at the terminal building, while vehicular traffic on the airport expressway was limited to a maximum speed of 40 kilometers per hour.

Meanwhile, the Beijing-Tianjin-Tanggu Expressway and the Beijing-Shijiazhuang Expressway were closed to traffic at 4 a.m. and 6 a.m., respectively.

According to an expert with the Central Meteorological Station, the fog was caused by a mixture of dense humidity, light wind, and relatively high temperatures.

Air traffic is expected to return to normal around noon, when the fog is expected to disperse. About 200 flights are expected to be delayed during the period, said an airport official.

Key Highway to Beijing Closed

The Shengyang-Shanhaiguan highway, a trunk road linking Beijing with China's northeast region, was closed Thursday due to the severe fog in this capital of Liaoning Province.

The visibility is less than 200 meters on the road, according to the local meteorological bureau.

The rainy and foggy weather has caused a traffic accident Wednesday morning on one section of the highway, causing the death of three people and injuring 24.

Local traffic management departments have began to restrict the passing of vehicles on several highway routes between key cities in the province.






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