Impact of Sea-land Breeze on Air Quality and Compositions of Particulate Matters in Qinhuangdao
To study the impact of sea-land breeze on atmospheric pollution in Qinhuangdao,a research was conducted based on meteorological and atmospheric pollution observations.Backward trajectories and aerosol lidar were used to investigate the differences in horizontal transport and vertical conveying of particulate matters under sea-land breeze and non-sea-land breeze conditions.The findings revealed that high PM2.5 and O3 concentrations were present in the southwest wind direction.On days with sea-land breeze,the PM2.5 concentration was higher than that on days without sea-land breeze.Furthermore,the concentration of PM2.5 components significantly increased on days with sea-land breeze.In autumn,the O3 concentration on days with sea-land breeze was notably higher than that on days without sea-land breeze.The removal of air pollutants by sea-land breeze in Qinhuangdao depended on the paths of air masses.On days with sea-land breeze,if the air masses passed through the polluted region south of Qinhuangdao,they could transport air pollutants,leading to enhanced secondary transformation and an increase in particulate matter concentrations.To tackle atmospheric pollution in Qinhuangdao,it is crucial to strengthen forecast and early warning of pollution transmission in the southern region.