南京北郊气溶胶粒子的光学散射特征

摘要

Measurements of atmospheric aerosol scattering coefficient (ASC) over the northern suburbs of Nanjin from 2009 to 2010 are carded out by the Integrating Nephelometer. Analysis results show that ASC has obvious seasonal variations with the lowest in spring, the highest in fall, and little difference between summer and winter. The ASC ranges from 51.6 Mm-1 to 2 748.3 Mm-1 with the average of 478.6 Mm-1 in different seasons. The diurnal variation of ASC shows a bimodal distribution. The ASC has a positive correlation with air relative humidity. It also has a close correlation with surface wind direction, and it is the highest when the wind is blowing easterly, followed by the southey and westerly wind. Aerosol can be significantly removed by precipitation. There is a negative correlation between the visibility and ASC when the visibility higher than 5 km. The ASC shows the biggest positive correlation with SO2 (0. 68 ) in autumn and NO2 (0.62) in spring which is significant at the 95% confidence level.%利用三波段积分浊度仪对南京北郊2009-2010年四季气溶胶散射系数进行观测和分析。结果表明：气溶胶散射系数具有明显的季节变化特征，春季最低，秋季最高，冬夏季差别不大；气溶胶散射系数变化范围为51．6～2748．3Mm-1，平均值为478．6Mm-1。气溶胶散射系数的日变化特征为双峰型。空气相对湿度与气溶胶散射系数呈正相关关系：地面风向与气溶胶散射系数关系密切，偏东风时气溶胶散射系数最大，偏南风和偏西风时气溶胶散射系数较小。降水对气溶胶有明显的清除作用。能见度大于5km时，能见度与散射系数呈负相关关系。四季大气中SO2和NO2与气溶胶散射系数存在一定相关性，其中秋季SO，与气溶胶散射系数的相关系数最大（0．68），春季NO2与散射系数的相关系数最大（0．62），均通过0．05信度的显著性检验。