Spatio-temporal Distribution Characteristics Of PM_2.5 And O₃ In Taiyuan

At present,the main pollutants in China are fine particulate matter(PM_2.5)and ozone（O₃）,which will harm human health when the pollution is serious.With the continuous deepening of air pollution prevention and control actions,the treatment of fine particulate matter(PM_2.5)in Taiyuan has achieved good results,but ozone（O₃）is found to be in a steady upward trend.Based on the data of Taiyuan ground monitoring station from 2016to 2020,this paper studies the spatiotemporal distribution characteristics of PM_2.5and O₃in Taiyuan.With the help of Arc GIS software,the inverse distance weight method is used to display the spatial visualization of PM_2.5and O₃mass concentrations,and the correlation between various pollutants is analyzed,and the negative correlation mechanism of PM_2.5and O₃is further analyzed.The main conclusions are as follows:（1）From 2016 to 2020,the concentration of PM_2.5in Taiyuan showed a downward trend,and the change of PM_2.5concentration had obvious seasonal characteristics,generally the highest in winter,the lowest in summer,and the concentration of PM_2.5increased significantly during the heating period.In terms of spatial performance,the pollution level of PM_2.5at Jinyuan and Xiaodian stations is higher than that at other stations in summer,and the overall pollution level of PM_2.5is higher in winter.The pollution problem in the urban center represented by Taoyuan station is prominent.At the same time,Jinyuan and Xiaodian stations are still the most polluted areas.（2）In 2016-2020,the concentration of O₃in Taiyuan showed an overall upward trend,and the daily average of ozone in the year was"single peak".The number of days of ozone exceeding the standard in 2016-2020 was 8 days,64 days,58 days,70 days and 65days respectively.At the same time,ozone had obvious seasonal variation characteristics,with the highest in summer and the lowest in winter.In terms of spatial distribution,Nanzhai and Jinsheng were the sites with the most serious ozone pollution in 2016.After2017,the ozone concentration rose as a whole,and Jiancaoping,Xiaodian and Jinsheng had the worst performance.（3）In the correlation analysis study,the correlation between PM_2.5and PM₁₀and CO reached 0.871（P<0.01）,and the homology of the three pollutants was the strongest compared with other pollutants.O₃has a negative correlation with other pollutants such as PM_2.5,and the concentration variation of O₃and PM_2.5shows a certain negative correlation under conditions of low temperature,low atmospheric oxidation,low radiation intensity,and high relative humidity.