天津城区秋冬季黑碳气溶胶观测与分析

利用天津大气边界层观测站2010年9月—2011年1月黑碳气溶胶、PM2.5质量浓度、大气能见度及常规气象观测数据,研究天津城区秋冬季黑碳气溶胶污染特征.结果表明,天津秋冬季黑碳气溶胶质量浓度均值7.24μg.m-3和6.46μg.m-3,分别占PM2.5质量的9.42%和7.98%,其吸收作用分别贡献大气消光的17.2%和17.6%;采用最大频数浓度法计算黑碳浓度本底值为2.50μg.m-3;黑碳浓度的日变化特征与天气过程有关,雾和霾天气下黑碳浓度较高,降水利于清除黑碳污染,秋季高浓度黑碳除局地源污染外,可能还与河北、山西、天津等地燃烧秸秆有关.

Observational and analysis of black carbon aerosol in the autumn and winter in Tianjin

Based on the data on the black carbon aerosol(BC),PM2.5 mass concentration,visibility and meteorological condition at Tianjin boundary layer station from September 2010 to January 2011,characteristics and influencing factors of BC concentration variation were analyzed.The results show that the average concentration of BC was 7.24 μg·m-3,and its mass percentage in PM2.5 was 9.42% in the autumn,while the average concentration was 6.46 μg·m-3,and mass percentage was 7.98% in the winter.The extinction proportion of BC was 17.2% in autumn and 17.6% in winter.BC diurnal variation of concentration related to the weather processes such as fog and haze with low visibility,while precipitation removed black carbon pollution.Burning of straws from the southwest and south region such as Hebei,Shanxi and Tianjin contributed to high concentrations BC in autumn.