基于光学遥测技术的合肥市气溶胶参数观测

Aerosol Properties by Optical Remote Sensing Techniques in Hefei City

为了解合肥市气溶胶光学特性参数,采用太阳光度计CE318对雾霾期间气溶胶进行监测并分析了气溶胶光学厚度(AOD)、Angstorm波长指数(α)、体积谱函数等气溶胶光学特性参数。同时采用多轴差分吸收光谱技术(MAX-DOAS)反演了雾霾期间二次气溶胶前体物NO2柱浓度并和固定点测量的颗粒物(PM)浓度进行了对比。分析表明,雾霾期间的气溶胶光学厚度比晴天高,且随波长的增加而减少。Angstorm波长指数在雾霾天气时平均值较高,表明合肥雾霾天气期间气溶胶粒子以细粒子为主。气溶胶前体物NO2浓度变化与雾霾天气空气中颗粒物含量(PM10、PM2.5等)变化一致性较好,表明二次气溶胶可能对气溶胶颗粒浓度有一定影响。

In order to get knowledge of aerosol optical properties, such as aerosol optical depth （AOD）, Angstorm wavelength exponent（ct） ,single scattering albeo（to） , during the haze-fog period, a sunphotometer CE-318 was operated in Hefei from 2012 to 2013. Simultaneously we retrieved tropospheric differential slant column density （SCD） of NO：, which is secondary aerosol precursor, by muti-axis differential optical absorption spectroscopy （MAX-DOAS） and made some comparisons with PM10 acquired from point monitoring station. It is found that mean Angstorm wavelength exponent is relative high during haze-fog period, which indicates fine panicles is predominant. The well consistency of NO2 concentration variation with PM changing indicates secondary aerosol may have some contributions to total aerosol particle concentration.