安徽寿县黑碳气溶胶浓度观测分析研究

Observational study of black carbon at Shouxian in Anhui Province

为了研究中国东部典型乡村黑碳气溶胶浓度变化特征,利用2015年11月-2018年11月安徽寿县国家观象台污染物浓度及常规气象观测数据对该地区黑碳气溶胶浓度变化特征及其影响因子进行讨论.结果表明,3年间寿县黑碳气溶胶年平均浓度逐年递减,分别为2.84、2.10和1.31μg·m^-3.季节变化特征显示,该地区冬季观测结果最高,为3.95μg·m^-3,是夏季的2.9倍.日变化特征显示,日最大浓度值在春、夏、秋三季通常出现在6:00-10:00,而冬季则出现在20:00.从观测结果的日变化幅度来看,冬季的日变化幅度最大,日较差为1.53μg·m^-3,春、夏两季次之,秋季最小,为0.48μg·m^-3.由于人为活动影响小,寿县地区黑碳气溶胶的周末效应不明显.此外,统计结果表明,风向风速对该地黑碳气溶胶浓度的影响最大,西北风天气条件下观测结果通常较高,而其余气象因子的影响相对较小.

In this study, we have conducted the measurements of atmospheric black carbon(BC) with the Aethalometer(Model AE-33) to study their characteristics over a rural area, Shouxian in Anhui Province of Eastern China. Further, the atmospheric BC data measured at Shouxian National Station was made to investigate and establish the correlation with the related air pollutants and meteorological data during the period from November 2015 to November 2018. The results revealed that the continuous and real-time atmospheric BC data observed at Shouxian over a period of 3 years showed a declining trend, with an average annual mean BC concentration of 2.84, 2.10 and 1.31 μg·m^-3 during 2016, 2017 and 2018, respectively. The mass concentration of atmospheric BC presented an obvious characteristics during different seasons. In winter, the BC mass concentration was found the highest with 3.95 μg·m^-3 which is almost 3 fold larger than that notice during summer(1.36 μg·m^-3).The diurnal pattern of BC mass concentration showed two peaks with significant changes varied in all four seasons which was more dominant during winter. We noticed maximum peaks between 6:00 and 10:00 local time(morning) and at 20:00 in winter during the entire study period. Additionally, the daily variation in BC concentration during winter was the largest, with a daily difference of 1.53 μg·m^-3 followed by spring and summer seasons, with the smallest depicted in autumn of 0.48 μg·m^-3. The weekend effect of BC was observed rather insignificant at Shouxian, indicating that the local anthropogenic emissions were relatively weaker. In addition, surface measured meteorological data such as wind direction and wind speed had substantial effect on the atmospheric BC concentrations. High concentration of atmospheric BC was found more frequently appended with the northerly winds. Whereas, the atmospheric BC concentrations were influenced weakly with the other meteorological factors.