摘要
利用京津冀中南部10个城市环境监测国控站点的2014~2016年PM_(10)、PM_(2.5)浓度逐小时资料和中国气象局地面观测逐小时国家站降水资料,进行对比统计分析,探讨降水对PM_(10)、PM_(2.5)的湿清除作用。结果表明,京津冀中南部降水对PM_(10)、PM_(2.5)湿清除效果随降雨总量、平均雨强、降水持续时间的增加而加强。当降雨总量大于10mm、平均雨强大于1mm、降水持续时间超过10h时,降水对PM_(10)、PM_(2.5)湿清除效果最佳。降水前PM_(10)、PM_(2.5)浓度与清除率呈非线性正相关关系,随浓度的增加,清除率将趋于稳定。
In this paper,we analyzed the effect of precipitation scavenging PM_(10) and PM_(2.5),based on the hourly data of PM_(10) and PM_(2.5) in 10 cities in central and south of Beijing-Tianjin-Hebei region,and the hourly precipitation data of the ground observation of China Meteorological Bureau. The results showed that the effect of precipitation on PM_(10) and PM_(2.5) was strengthened with the increase of rainfall amount,average rainfall intensity and duration of precipitation. When the total amount of rainfall was greater than 10 mm,the average rainfall was stronger than 1 mm,and the precipitation duration exceeded 10 h,the precipitation had the best effect for PM_(10) and PM_(2.5) removal. Pre-precipitation PM_(10) and PM_(2.5) concentration and clearance rate did not showed linear relation. With the increase of concentration,the clearance rate tended to be stable.
引文
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