乌鲁木齐市近地面O_3与前体物及颗粒物相关性分析

Correlation Analysis of Surface Ozone with Precursors and Particles in Urumqi

利用2016年10月~2018年2月乌鲁木齐市近地面O_3、PM_(2.5)、PM_(10)、NO_2、CO的连续观测资料,主要分析乌鲁木齐市O_3浓度的变化特征与部分前体物质、颗粒物之间的关系。结果表明:(1)2017年月分布:监测期间乌鲁木齐市O_3平均浓度为79.33μg/m^3,O_3浓度较高主要集中在6~9月份,其平均O_3浓度为121.14μg/m^3。O_3季平均浓度整体呈现出夏季>春季>秋季>冬季。(2)时间分布上:O_3小时浓度的日变化分布呈现"单峰型"特点,且日间浓度明显高于夜间。一般在15∶00~16∶00左右达到峰值浓度;空间分布上:对照点浓度>城区监测站点,城区外围站点浓度>城区监测站点的特征。(3)在O_3与前体物CO、NO_2及与OX之间的关系中,O_3与CO、NO_2均呈显著的负相关关系,相关系数分别为-0.789(P<0.01)、-0.871(P<0.01),与OX呈显著正相关关系(r=0.985,P<0.01)。(4)O_3与大气颗粒物PM_(2.5)、PM_(10)呈明显的负相关关系,其相关系数分别为-0.754(P<0.01)、-0.718(P<0.01)。

The characteristics of surface ozone concentration change and its relationship with some precursors and particulates such as PM10,PM2.5,O3,NO2and CO were analyzed by continuous observation at nine sites of Urumqi from October 2016 to February 2018.The results indicated that during the observation period,the monthly distribution analysis showed that the averaged concentration of ozone in Urumqi was 79.33μg/m^3in 2017.The higher concentration was averagely 121.14μg/m^3,mainly scattered from June to September.The seasonal average concentration generally presented as highest in summer,followed by spring,autumn and winter in a descending order.With regard to the daily distribution characteristics of ozone,hourly averaged concentration appeared＂unimodal＂,and the daytime concentration was significantly higher than that at night,with peak between 15∶00 and 16∶00 generally.With regard to the spatial distribution of O3,concentration in the central urban area was lower than that in the background station,and concentration in the periphery of the central urban area was higher than that in the central urban area.With regard to the relationship between ozone and some precursors such as CO,NO2and OX,concentration of ozone had a significantly negative correlation with that of CO and NO2,and the correlation coefficient was-0.789（P〈0.01）and-0.871（P〈0.01）.However,concentration of ozone had a significantly positive correlation with that of OX,and the correlation coefficient was 0.985（P〈0.01）.Concentration of ozone had a significantly negative correlation with that of PM10and PM2.5,and the correlation coefficient was-0.754（P〈0.01）and-0.718（P〈0.01）.