我国东部沿海春季主要大气污染物垂直分布及来源模拟研究

Simulation about Vertical Distribution of Main Air Pollutants and Sources in the Atmosphere in China′s East Coast in Spring

利用2011年3月22日—4月26日在青岛沿海地区及青岛—济南—西安转场航测数据和CMAQ(4.7.1)模式分析了不同航次我国东部沿海春季大气污染物浓度的垂直分布。结果表明,模拟值与监测值有较好的一致性;污染物浓度呈现明显的空间分布特征和时间变化特征;垂直方向上污染物浓度随高度的增加呈下降趋势,污染物主要集中在3000m以下;水平方向上污染物浓度分布与污染源位置相对应,呈现出由城市边缘向城市中心推移递增的趋势及区域性特征。通过后向轨迹聚类及情景模拟分析发现,春季我国东部近海大气污染物主要来自山东省、京津冀、江苏省和辽宁省,且随着高度增加京津冀地区污染物的分担率及背景、边界条件对各受体点污染物贡献率逐渐升高。

CMAQ （4.7.1） model was employed, in data from China＇s east coastal areas as well as from April 26th 2011, to analyze the vertical distribution data were in well consistent with the observed data combination with gaseous pollutants data of aircraft observation Qingdao city, Jinan city and Xi＇an city from March 22th to of gaseous pollutants. The results showed that the simulated and there existed obvious vertical distribution and temporal variation characteristics. Concentrations of pollutants in the vertical direction decreased with height on the whole and mainly concentrated at below 3 000 m; the distribution of pollutant concentration in horizontal direction coincided well with that of polluting sources, both increased from edges to centers of the cities. The analysis of trajectory clusters and source receptor apportionment found that pollutants in the east coast in spring mainly came from Shandong, Beijing-Tianjin-Hebei, Jiangsu and Liaoning provinces/municipalities; the contribution rate of contaminants from Beijing-Tianjin-Hebei region and background, boundary conditions gradually increased as the altitude increased at different receptor sites.