Abstract:
This paper analyzed the pollution characteristics and current situation of pollutants by collecting realtime monitoring data of SO
2,NO
2,CO,O
3,PM
10,PM
2.5 in seven cities of Tibet Autonomous Region from 2015 to 2021.The results showed that the annual average concentrations of PM
2.5,PM
10,SO
2,NO
2 and CO were relatively stable,and the concentrations of O
3 and NO
X showed an upward trend.The average concentration of O
3-8h increased from 105 μg/m
3 in 2015 to 124 μg/m
3 in 2021.O
3 concentration over the standard mainly occurred from May to August.The monthly average concentration of PM
2.5 showed significant seasonal difference.The content of PM
2.5 was low in summer (July-September) and high from November to March of the next year.The comprehensive air pollution index was less than 5,and the ratio of excellent days was 98.5%~99.7%.In the statistical years,the annual average concentration of O
3 and PM
2.5 in 2015 and 2016 reached the standard II,and the annual average concentration of the other four evaluation indicators reached the standard I,and the ambient air quality in the whole region remained good.The ratio of NO
2/SO
2 in Lhasa City and Changdu City was larger than the ratio in Naqu City and Ali City.The research results would provide reference for air pollution control in Tibet Autonomous Region.