成都市区夏季臭氧污染特征及与气象因子的关系研究

Characteristics of Ozone Pollution and Its Relationship with Meteorological Factors in Urban Chengdu during Summer

利用成都市区2019年6-8月臭氧浓度数据和同时期地面气象观测资料分析表明(1)8月臭氧浓度最大,超标时数最多,6月次之,7月最小;(2)臭氧浓度和超标时数日变化呈“单峰单谷”型,峰值在16时,臭氧浓度滑动8 h平均值较小时平均值推后3 h;(3)臭氧浓度与气温、日最高气温、日照时数显著正相关,与相对湿度显著负相关;(4)风速小于1.5 m/s时,臭氧浓度随风速增加而增大,盛行西风和南风时,易出现臭氧浓度高值,盛行北风时臭氧浓度较低。

The characteristics of ozone pollution and its relationship with meteorological factors were studied by using the hourly ozone concentration data and national meteorological observation data in Chengdu from June to August 2019 in urban Chengdu.The results showed that:(1)the average concentrations and over standard hours of hourly ozone in August was the highest,followed by that in June,and the lowest was in July.(2)The daily variation of ozone concentrations and over standard hours was“single peak single valley”type,with the peak at 16:00 BST,and the sliding eight-hour average ozone concentration was three hours after the hourly ozone concentration.(3)The concentration of ozone was positively related to temperature,daily maximum temperature and sunshine duration,and negatively related to relative humidity during summer.(4)When the wind speed was less than 1.5 m/s,the ozone concentration increased with wind speed.When the wind speed was greater than 1.5 m/s,the ozone concentration decreased with wind speed.Urban Chengdu mainly had higher ozone concentration in the west and south wind direction,while the ozone concentration was low under the influence of northerly winds.