温州城区大气污染特征数值模拟与来源解析

摘要

文章以位于温州城区的瓯海区为例,在建立大气污染源清单的基础上,利用WRF-CMAQ、CALPUFF模型分析了外来污染物区域输送对瓯海区的影响,模拟了瓯海区主要大气污染物浓度分布,解析了区域大气污染物排放来源.WRF-CMAQ模型模拟结果表明,区域大气污染物SO2、NO2、PM10和PM2.5的输送对瓯海区的贡献影响均呈现冬季(1月)>春季(4月)>秋季(10月)>夏季(7月)的变化规律,这可能与大气污染物来源有关.CALPUFF模型模拟结果显示,瓯海区SO2和PM10的年平均浓度达标,但NO2和PM2.5出现超标现象.除SO2均能达标外,部分敏感目标处NO2、PM10和PM2.5年平均浓度有不同程度的超标现象.来源分析结果表明,瓯海区大气污染物SO2和NO2主要来自本地源排放,而PM10和PM2.5本地源与外来源的排放贡献相当.%In this study, Ouhai District in the urban areas of Wenzhou City was taken as the example. On the basis of air pollution emission inventory, WRF-CMAQ and CALPUFF models were used to analyze the influences of regional transportation of external pollutants on Ouhai District, simulate the concentration distribution of major air pollutants in Ouhai District and resolve the regional sources of air pollutant emission. The results showed that the effects of regional transportation of SO2, NO2, PM10 and PM2.5 on Ouhai presented the maximal in winter (January), followed by spring (April), fall (October) and summer (July) in a descending order, indicating possible relation to the sources of air pollutants. The results from CALPUFF model simulation showed that the annual average concentration of SO2 and PM10 in Ouhai complied with the air standard, but that of NO2 and PM2.5 exceeded the limits regulated in the air standard. All the data related to SO2concentration in the sensitive targets was in compliance with the air standard, but that of the concentrations of NO2, PM10 and PM2.5 in some sensitive targets exceeded the limits in the air standard. The results from source analysis demonstrated that SO2 and NO2 in Ouhai were mainly from local pollution emission sources, while PM10 and PM2.5 were both from local and external pollution sources.