成都市大气水汽与空气质量关系的研究

为深入分析大气水汽对空气质量的影响,基于2016年成都温江国家气候观象台的气象观测资料和成都市环境监测中心的环境空气质量指数(AQI),首先利用地面气象要素估算出逐时的大气可降水量(PWV),继而结合空气质量指数资料研究了成都地区降水、静稳天气、太阳辐射强度等气象条件对空气质量及其与大气水汽关系的影响.结果表明:在降水条件下,臭氧(O_3)浓度随着PWV的增大而显著减小,PWV与PM_(2.5)、PM_(10)浓度的正相关系数减小,其中对PWV与PM_(10)浓度的相关性影响最大,相关系数减小47.62%.PWV与O_3的负相关系数在春季增大、夏季减小;PWV与PM_(2.5)的正相关系数在秋、冬季减小.当天气处于高静稳指数时,PWV变化对污染物浓度变化的影响更为显著.不同太阳辐射强度下,PWV与O_3的相关性也不同,随着太阳辐射增强,PWV与PM_(2.5)、PM_(10)的相关性从正相关转变为负相关.

Study on the relationship between the water vapor and the air quality in Chengdu

In order to further analyze the impacts of the water vapor on the air quality, based on the meteorological observation data of the National Climate Observatory at Wenjiang, Chengdu in 2016 and the Environmental Air Quality Index (AQI) of the Chengdu Environmental Monitoring Center, the ground meteorological elements are firstly used to estimate the hourly atmospheric state. Precipitation (PWV), combined with the air quality index data, is used to study the impacts of the meteorological conditions such as precipitation, the static stability atmosphere and the solar radiation intensity on air quality and their relationships with the water vapor. The results show that under the precipitating conditions, the concentration of ozone (O₃) decreases significantly with the increase of PWV, and the positive correlation coefficient between PWV and PM_2.5, PM₁₀, which has been impacted the most with the correlation coefficient decreasing by 47.62%. The negative correlation coefficient between PWV and O₃ is enhanced in spring and weakened in summer and the positive correlation coefficient between PWV and PM_2.5 is weakened in autumn and winter. When the atmosphere is at a high static stability state, the PWV change is more significant with the variations of the AQI and other pollutant concentrations. The correlation between PWV and O₃ is different under different solar radiation intensity. With the increase of the solar radiation, the correlation between PWV and PM_2.5/PM₁₀ changes from positive correlation to negative correlation.