How much has the national average concentration of PM2.5 decreased in five years?

On February 1 1 day, China Meteorological Bureau issued the Bulletin of Atmospheric Environment Meteorology for 20 17 (hereinafter referred to as the Bulletin). The communique mentioned that since 2000, China's atmospheric environment as a whole has shown a trend of "early deterioration and late improvement", especially since the implementation of the 20 13 Air Pollution Prevention Action Plan, China's atmospheric environment has been continuously improved, and emission reduction measures have achieved remarkable results.

According to the communique, in 20 17, there were six large-scale haze weather processes in China, which was less than in previous years. Among them, the average number of haze days in China is 27.5 days, which is 10.5 days lower than that in 20 16 years and 19.4 days lower than that in 20 13 years.

In 20 17, the average number of haze days in Beijing-Tianjin-Hebei, Yangtze River Delta and Pearl River Delta regions was 42.3 days, 53.3 days and 17.9 days, respectively, which decreased by 18. 1 day, 17.6 days and 3.2 days compared with 2006.

According to the data from the Environmental Monitoring Center of the Ministry of Environmental Protection, the national average concentrations of PM 10 and PM2.5 in 20 17 were 75 μ g/m3 and 43 μ g/m3, respectively, which were 5. 1% and 6.5% lower than that in 20 16, respectively.

Zhang Hengde, a senior engineer of the Central Meteorological Observatory of China Meteorological Bureau, said that there are two main reasons for the improvement of the national atmospheric environment. One is that the emission reduction effect has been remarkable since the implementation of the Action Plan for Air Pollution Prevention and Control, and the other is the general preference of meteorological conditions for air pollution diffusion in 20 17 heating season.

According to the meteorological numerical simulation results, the average concentration of PM2.5 in China, Beijing-Tianjin-Hebei, Yangtze River Delta and Pearl River Delta decreased by 45.3%, 38.7%, 32.4% and 30.2% respectively in 20 17, and by 7.5% and 16 respectively in 20 16.

The communique also mentioned that from 20 14 to 20 16, the national average concentration of PM2.5 decreased by 23.8%, 38.5% and 40.2% respectively compared with 20 13.

Zhang Hengde said that the meteorological conditions of air pollution diffusion in the heating season of 20 17 (1, February and1,12) are generally better than that of 20 13 ~20 16.

Specifically, the number of windy days in Beijing, Tianjin and Hebei is 3.1%less than that in 20 16 years; Compared with the same period of 20 16, the static weather index of Beijing-Tianjin-Hebei region in June 5438+0 1 0 and February16 decreased by 4.4% and 13.5% respectively, and that of Beijing region decreased by 8. 1% and16 respectively. Zhang Hengde said that the reduction of windy days and static weather is conducive to the diffusion of atmospheric pollutants and the improvement of the atmospheric environment.