河西走廊干旱区气溶胶粒子光吸收特征

 利用2008年4—6月在张掖气候观象台的黑碳仪观测资料,结合同时期的PM10浓度和气象要素观测结果,分析了河西走廊干旱区的气溶胶吸收系数变化特征。讨论了气溶胶总体特征、日变化特征、局地风对吸收性气溶胶的输送以及沙尘天气下气溶胶吸收系数变化特征,并估算了沙尘气溶胶的质量吸收系数。结果表明,观测期间气溶胶吸收系数（532 nm）的平均值（标准差）为11.9 Mm-1（10.1 Mm-1）。一日内气溶胶吸收系数有明显的日变化,早（08:00）晚（21:00）有两个峰值,且夜间的气溶胶吸收系数值较白天要高。风向的昼夜转换是影响气溶胶吸收系数日变化的一个重要原因。沙尘气溶胶也有一定的吸收性,其质量吸收系数估算为0.016 m2·g-1。

Light Absorption Properties of Aerosol Particles in Arid Area of Hexi Corridor

The aerosol absorption coefficient(σap) was measured with an aethalometer at Zhangye observatory from March to June in 2008,in combining with the mass concentration of PM10 and the routine weather observation data,and a comprehensive analysis was conducted.We analyzed the general and diurnal variation features of σap.Also we discussed absorptive aerosol transported by local wind and the variation feature of σap during a dust event.It is found that aerosol absorption coefficient at 532 nm had a mean value of 11.9 Mm-1,with standard deviation of 10.1 Mm-1.The diurnal variation of σap was significant,with two peaks at morning(08:00) and at night(21:00),and σap was higher in the night than in the daytime.The diurnal variation of wind direction was one of the main impact factors causing diurnal variation of σap.The dust aerosol also absorbed light,and its mass absorption efficiency was estimated to be 0.016 m2·g-1.