[Analysis of Characteristics and Causes of a Typical Haze Pollution in Beijing in the Winter of 2019].

In order to study the pollution characteristics and causes of winter haze pollution in Beijing, a typical PM pollution process in Beijing in December 2019 was used as the analysis object using aerosol vertical detection data, boundary layer meteorological field and near-ground turbulence data, and the difference in haze. The characteristics of the pollution stage and the evolution of the physical and chemical characteristics of the boundary layer were comprehensively analyzed. The results showed that ① the pollution process in Beijing during the observation period lasted 5 d and experienced two generations and eliminations.