Changes Of Spatiotemporal Dynamics Of Atmospheric Aerosol In Ling’an And Tianmu Mountain Of Zhejiang

In this paper,CE-318 instruments are used to obtain AOD data of Ling’an,Zhejiang,the foot of Mount Tianmu and the peak of Tianmu Mountain from January 2015 to December 2016.The instruments are made by the French company and tracked automatically.And combined with the meteorological data of PM_2.5 and NOAA,and simulated the trajectory of airflow during fog and haze.the combination of two phases are draw a backward trajectory chart to analyze the pollutant composition and the source area.To show that atmospheric aerosol characteristics in Ling’an and Tianmu Mountain.Innovation is the study of forest and urban differences in a small area.Different from the previous large-scale regional research.During the haze period,using the HYSPLIT backward trajectory model to explore the correlation between AOD and PM_2.5.the source apportionment of pollutants was carried out.It is helpful to understand the climate conditions,the pollutant sources and can accomplish scientific prediction to predict the concentration of atmospheric particulate matter,and to take effective measures to control and make human preventive work.You can also get effective reference in controlling the wanton pollution of atmospheric particulates.In addition to the protection of the security problem of life of human beings.Therefore,the accurate prediction of the concentration of atmospheric particles is of far-reaching practical significance.The main research results are as follows:a)The results of AOD show that the the highest month of AOD value was July,AOD（550nm）=1.2004,the minimum month is October,AOD（550nm）=0.3553,in the study area of Ling’an.The AOD of Tianmu Mountain shows the bimodal curve,both in June and September.According to the season,the monthly average value of Ling’an was 0.8162,and the monthly average value of the foot of Mount Tianmu was0.929,and the highest monthly average value of the peak of Tianmu Mountain was 0.6378.The AOD value of the foot of Ling’an and Tianmu Mountain are larger in winter and summer than in spring and autumn.The AOD value of the peak of the Tianmu Mountain is larger in spring and autumn than in summer and winter.b)（?）ngstr（?）m Index a（between 0.7 to 1.8）is a mixture of continental aerosol.Seasonal variation and the change of AOD was negatively correlated.For 2015-2016 years,aerosols in Ling’an mainly came from urban industrial aerosols or biomass burning aerosols.In January,February and July,the peak of Tianmu Mountain is an urban industrial aerosol,aerosol for biomass burning in August,in November and December,it was controlled by sand dust weather.More than half of the month at the foot of Mount Tianmu is industrial aerosol.The （?）ngstr（?）m Index a of Ling’an and the foot of Tianmu Mountain is smaller in winter and summer than in spring and autumn,and the peak age of Tianmu Mountain is smaller in spring and autumn than in winter and summer.c)Turbidity coefficient b（the highest value in three places,respectively）appeared in Ling’an in June,Tianmu Mountain peak in September and the foot of Tianmu Mountain in November,respectively0.3646,0.7029,0.1932.The highest values of turbidity coefficient in the three place were found inLing’an in June,the peak of Tianmu Mountain in September and the foot of Tianmu Mountain in June,respectively,0.3646,0.7029 and 1.3051.The seasons in Ling’an and Tianmu Mountain are consistent with AOD.The AOD value of the foot of Ling’an and Tianmu Mountain are larger in winter and summer than in spring and autumn.The AOD value of the peak of the Tianmu Mountain is larger in spring and autumn than in summer and winter.d)The average valley value in 2015 PM_2.5 was 31 μg/m3 in July,and the peak value was 86.5μg/m3 in January.In 2016,the average valley value of Ling’an PM_2.5 in July was 25.2 μg/m3,the peak value was 65.4 mu g/m3 in March,and the second high month was 63.1 μg/m3 in January.Within two years,PM_2.5 was the smallest in July,and AOD reached its highest in June and July,and reached its minimum in May and July.e)According to the analysis of air trajectory: during the haze period,in 2015 December 19-24 th Ling’an’s first pollutants came from local emissions and dust in the northwest.The second time in December 19-31 th,the haze generated particulate sources: long-range particles,,dust particles in the north and West,and the neighboring region of exogenous transmission.In 2016,the first 10-11 to 10-12,the haze event pollutants mainly long-distance transmission,mainly from the northwest dust particles,the trend of the three elevation is basically the same.Ling’an.October 1,2016,during the haze occurred,most of the sources of particulate matter in Ling’an come from sea salt particles in the Yellow Sea and the East China Sea.,near the ground pollution mainly in Ling’an and other surrounding areas.