Large-scale air pollution strikes Beijing, Tianjin and Hebei

At present, 34 cities at or above the prefecture level, including Beijing, Tianjin, Shijiazhuang, Taiyuan, Zhengzhou and Jining, have issued orange warnings, timely taken emission reduction measures and reminded the public to do a good job in health protection.

Experts organized by the National Joint Center for tackling key problems in air pollution control predicted and analyzed that in late March, the atmospheric circulation situation in North China was active. With the rise of the subtropical high in the north, the temperature continued to rise. The warm and humid air flow dominated by southerly winds and easterly winds sent a large amount of water vapor to Beijing, Tianjin, Hebei and the surrounding areas, which was prone to adverse meteorological conditions such as static stability and high humidity.

In terms of pollutant emission, with the end of the heating period, various industrial enterprises with staggered peak production in autumn and winter began to resume production. While the emission of civil heating was reduced, the emission of industrial production and cargo transportation was significantly increased. Due to the industrial structure of Beijing, Tianjin, Hebei and surrounding areas, which is dominated by heavy chemical industry, and the transportation structure characterized by highways, the emission intensity of major pollutants is still at a high level.

For this pollution process, the forecast results show that from March 25, the upper atmospheric circulation situation is stable, the middle layer is heating up, the regional diffusion conditions are unfavorable, and the pollutants will gradually accumulate in the central part of Beijing, Tianjin and Hebei, the central and northern cities of Bohai Bay and the urban agglomeration of central Liaoning due to the influence of the near surface southerly wind and the early morning temperature inversion. On the 27th, the diffusion conditions further deteriorated, and it is expected that the pollution area will continue and may expand to cities along the east side of Taihang Mountain. On the 29th, affected by the cold air in the northeast, the pollution process in the central part of Beijing, Tianjin and Hebei ended. The downwind cities in the southern part of Beijing, Tianjin and Hebei and Henan were affected by the pollution transit, and short-term medium to heavy pollution may occur. Experts said that the pollution mitigation situation in the later stage needs to be further tracked, studied and judged.