Study on Ozone Source and Its Generating Sensitivity in Northeastern Guangdong during Autumn
Ozone pollution in Guangdong Province was much more serious in autumn.In this paper,air pollution in Meizhou,a city in northeast Guangdong was simulated and evaluated by the 3-dimensional air quality model,ozonegenerating process and sensitivity were studied,and the source apportionment was quantified by a variety of comprehensive means.Influenced by northeast wind,despite its higher wind speed,ozone-generation became active due to the strong sunshine.In Meizhou City,major part of the ozone concentration in autumn,up to 60% in the afternoon was due to the local background ozone,and the local emissions contributed about 10%,the maximum was about 10 μg/m3 in the afternoon,on the other hand,the external emissions contributed 30%,of them the maximum contributions of Jiangxi and Fujian provinces were 23 and 11 μg/m3 respectively,while the contribution of other cities in Guangdong Province was less than 1 μg/m3.Regarding the sources categories,power plants and elevated industrial source as well as aircraft emissions constituted the largest contribution to autumn ozone concentration,ca 17~20 μg/m3.In autumn,the ozone-generating sensitivity shifted from NOx sensitive in the morning to VOCs sensitive at noon,and finally turned into NOx sensitive at sunset.As far as the daily average,ozone was mainly generated in the VOCs sensitive zone.In conclusion,to reduce ozone pollution in northeastern Guangdong,it was important to curb emissions from power plants and elevated industrial sources in the north,meanwhile to control VOCs pollution too.