Simulation And Analysis Of Heavy Pollution Prcess In Winter In Shenyang Based On WRF-Chem

In recent years,Shenyang has witnessed frequent heavy pollution weather in winter.In this paper,numerical model WRF-Chem simulation results and actual observation data are used to analyze the two heavy pollution processes in the winter of 2019 in Shenyang.The source of pollutants is analyzed by HYSPLIT model.And verify the accuracy of WRF-Chem model for the simulation of heavy pollution weather process in Shenyang.The following are some conclusions:（1）The results show that the simulation effect of the WRF-Chem model is better.good on meteorological elements.When the correlation coefficient between the observed and simulated values of temperature and air pressure is above 0.85,the simulation effect is the best,the simulation effect of wind direction is low.The simulation results of PM2.5 and PM10 are lower than that of actually observed,and the simulation effect of PM2.5 is higher than that of PM10.The simulation results are basically consistent in the high number area and low number area,and the time of peak number.（2）The time distribution of particulate matter（PM）in Shenyang is mainly due to the long heating time in winter,which makes the concentration of PM in spring and winter is greater than that in summer and autumn.The concentration of PM during peak hours in the morning and evening is greater than in other periods.The high concentrations of PM are mainly distributed in Hunnan District and Tiexi District where there are more industrial parks.（3）The temporal distribution of particulate matter in Shenyang is mainly due to the longer heating time in winter,which makes the concentration of particulate matter in spring and winter greater than that in summer and autumn.In terms of hourly changes,the concentration of particulate matter during peak hours in the morning and evening is greater than in other periods.In terms of spatial distribution,areas with high concentrations of particulate matter are mainly distributed in Hunnan District and Tiexi District where there are more industrial parks.（4）The air masses in Shenyang are mainly from the Beijing-Tianjin-Hebei region in the southwest（carrying a large amount of PM2.5）,the Inner Mongolia Autonomous Region in the northwest and the Hulunbuir Prairie in the northwest（carrying a large amount of PM10）.The main potential sources of PM2.5 are the Beijing-Tianjin-Hebei region and southern Hebei Province,and the main potential sources of PM10 are the northwest of Jilin Province,the Inner Mongolia Autonomous Region and the northwest of Heilongjiang Province.Under the influence of airflow,pollutants will move to Shenyang.What’s more the local emission source in Shenyang is also an important cause of heavy pollution weather.