Dynamic analysis of particulate pollution in haze in Harbin city, Northeast China

Abstract

Abstract Based on the air quality data of Harbin in winter from 2015 to 2017, the national winter straw combustion data from 2016 to 2017 and the mixed single particle Lagrange comprehensive track model, Hybrid Single-Particle Lagrangian Integrated Trajectory Model (HYSPLIT), dynamic analysis of Harbin’s winter air quality status and influencing factors. The air quality data were analyzed; it was found that the main pollutants in winter in Harbin were SO2, NO2, PM10 (particles with aerodynamic diameter ≤10 µm), and PM2.5 (particles with aerodynamic diameter ≤2.5 µm); the annual air pollution situation deteriorated sharply from November and continued until March of the following year. Through the research on straw fire prevention points in Harbin, the spatial pattern characteristics and causes of persistent haze in Harbin from 2015 to 2017 were dynamically analyzed. Combining the backward trajectory model to trace the source and trend of air mass in pollution, it is found that the air mass trend is consistent with the distribution of straw-burning points. The research results show that (1) during the winter from 2015 to 2017, the overall air quality situation in Harbin improved, the number of serious pollution days decreased year by year, and the main atmospheric pollutants were PM10 and PM2.5. In October and November, the pollution concentration peaked, and after December, the pollution concentration showed a downward trend until the next spring reached the valley and (2) the most obvious time of haze in Harbin is from November to December, and it is concluded that haze events are closely related to the large number of pollutants caused by the burning of straw around Harbin, and because the northwest monsoon climate affects the air quality, the transportation of fine particles caused by the burning of straw in winter in the surrounding areas of Harbin is the main cause of serious pollution in Harbin.