What are the human factors for the formation of apec Blue?

APEC Blue refers to the blue sky that appeared in Beijing during the 22nd APEC Economic Leaders' Informal Meeting. There are five factors contributing to the formation of APEC Blue, namely:

1. Motor vehicle restriction control: China, Beijing, Hebei, Tianjin and more than 8 cities adopt the policy of restricting the number of cars with single and even numbers, and 70% of the buses of government agencies and units are sealed.

Due to the implementation of measures such as motor vehicle single and even number restriction and muck truck restriction, foreign vehicles go to Beijing to bypass transit vehicles, the number of motor vehicles on the road decreases, the average speed of the road network increases, the total amount of motor vehicle pollutants decreases obviously, and the role of "agitator" decreases, thus reducing the generation of road dust. Based on the above calculations, the local contribution of motor vehicle emission reduction to the decline of PM2.5 during the session is 39.5%. Among them, foreign vehicles (especially heavy trucks and buses) bypass, motor vehicles in the city are restricted to single and even numbers, and muck trucks are prohibited from driving, which contributes greatly to the emission reduction of nitrogen oxides and VOCs.

2. Coal-burning and industrial enterprises stopped production: more than 2,000 enterprises in Hebei temporarily stopped production, 1.900 enterprises stopped production, and 1.700 construction sites stopped production. Forty-six five-level supervision teams in Hebei Province went to various places to supervise the implementation of various measures.

According to estimates, due to the measures taken by key industrial enterprises in Beijing to reduce the production load of coal-fired power plants, stop production and limit production, during the APEC meeting, the emissions of SO2, nitrogen oxides, PM 10, PM2.5 and VOCs decreased by about 207,374,97 and 495 tons respectively. Among them, the contribution of emission reduction is that key enterprises stop production and limit production, reducing nitrogen oxides and VOCs by 202 and 493 tons respectively. The local contribution of these measures to the decline of PM2.5 during the meeting was 17.5%.

3. Construction site shutdown: During the APEC meeting, all construction sites (except emergency repair works) in the administrative area of Beijing were shut down. The Beijing Municipal Commission of Housing and Urban-Rural Development requested that the dust control work during the shutdown should be done well.

Due to the measures taken by Beijing to stop the construction site and stop using some construction machinery, it is estimated that during the APEC meeting, the emissions of nitrogen oxides, PM 10, PM2.5 and VOCs will be reduced by about 375, 1693, 36 1 and 273 tons respectively. Among them, the shutdown of the construction site contributed greatly to the emission reduction of particulate matter, reducing the emission of PM 10 and PM2.5 to 1674 tons and 346 tons respectively, and the effect of off-road machinery on the emission reduction of nitrogen oxides was also obvious, reducing the emission by 375 tons. The local contribution of these measures to the decline of PM2.5 during the meeting was 19.9%.

4, strengthen the city road cleaning:

During the meeting, the key roads in Beijing were encrypted with "sucking, sweeping, flushing and collecting" operations, and daily washing was basically realized. According to the measured results, the road dust load decreased by about 40% on average. According to the emission factor method, after taking the above measures, the emission of PM 10 and PM2.5 decreased by about 1587 tons and 303 tons respectively, which was basically equivalent to the contribution of site shutdown. The local contribution of these measures to the decline of PM2.5 during the meeting was 10.7%.

Step 5 go on holiday

Vacation in Beijing involves a wide range, and changes in production and lifestyle can directly reduce the emission of air pollutants. According to the statistics of traffic flow in and out of Beijing and the number of mobile phones on the Internet, some citizens left Beijing during the holidays, which reduced the permanent population of the city by about10%; Due to the holiday of going to work and going to school, the city's traffic flow decreased by about 20% compared with that before the holiday; There are also some industrial enterprises that stop production during holidays, such as coal-fired boilers that run all the year round in Chengliu District and Huairou District. The local contribution of these measures to the decline of PM2.5 during the meeting was 12.4%.

20 14 During the APEC meeting in Beijing, Beijing, Tianjin and Hebei implemented measures such as road restrictions and the closure of polluting enterprises to ensure that the air quality reached a good level.