Black carbon (BC) aerosols influence climate by absorbing incoming solar radiation resulting in a war ming effect with large uncertainties. To better understand the anthropogenic BC pollution and its transport in the region of Shanghai, the BC mass concentrations are measured at Pudong (the urban site) and Dong tan (the suburban wetland site), during a one-year period from December of 2007 to November of 2008.The diurnal and seasonal variations of BC mass concentration and the wind-concentration relationships at two sites are compared. According to the Aethalometers, the hourly BC mass concentration of Pudong is 1.2-7.6 μg · m-3 (10％-90％ percentiles), with an average value of 3.8μg · m-3, which is significantly higher than that of Dongtan (0. 1-4.3 μg · m-3 , with an average of 1.7 μg · m-3). The BC concentrations show similar variation patterns at both sites in seasonal scale, with the highest concentrations usually observed in winter and the lowest concentrations in summer. However, different diurnal patterns are usually observed at different sites. The average diurnal variation measured at the urban (Pudong) site revealed a dual-peak pattern, with peaks between 09:00 and 10:00 and between 20:00 and 21:00, while the minimum values generally appear in the afternoon and midnight. The morning peaking is attributed to enhanced traffic during rush hour, while the evening rush hour combined with the collapse of convective boundary layer result in the evening peak. Additionally, pronounced "weekend effect" is observed at the urban (Pudong) site, when the average BC concentration of non-workdays is about 13％ lower than that of workdays. These results indicate that the BC concentration at Pudong site is mainly influenced by the local anthropogenic emissions. In contrast, neither significant diurnal variation nor significant "weekend effect" is observed at the suburban (Dongtan) site, indicating that the local anthropogenic emissions at Dongtan are relatively weaker. Surface wind direction and wind speed has substantial effects on the BC concentrations.Wind could either dilute BC aerosols or transport them from other places and contribute to the measured concentration, depending on different wind directions and speeds. Different characteristics of wind-concentration relationships are observed for urban and suburban areas in which the BC concentrations are mainly influenced by the local emissions and by the regional pollutant transport, respectively.%为了探讨上海市区和郊区黑碳气溶胶质量浓度、分布以及来源和输送等特征,利用上海浦东(市区)和东滩(郊区河口湿地)2007年12月-2008年11月的黑碳气溶胶小时平均质量浓度数据,对比分析了两地黑碳气溶胶浓度在不同时间尺度上的变化特征以及气象要素对黑碳质量浓度的影响.结果表明:观测期间浦东和东滩两地黑碳气溶胶小时质量浓度平均值分别为3.8μg·m-3,1.7μg·m-3.两地黑碳气溶胶浓度具有类似的季节变化特征,均为冬季较高、夏季较低;同时浦东黑碳气溶胶浓度日变化呈现出明显的双峰结构,并具有显著的周末效应,体现了局地人为源排放的影响.受源排放影响为主的市区与受输送影响为主的郊区,黑碳气溶胶浓度在不同风向上与风速的关系表现出不同特征.
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