典型污染天气黑碳气溶胶混合形态、表面结构、光吸收性质及其关系

气溶胶的气候效应是当前大气化学及相关领域的研究热点和前沿课题。本项目以典型雾、霾污染天气为背景，以长江三角洲为例，基于气溶胶飞行时间质谱（ATOFMS）、单颗粒黑碳测量仪（SP2）、电子显微镜（TEM/SEM）等先进技术表征单颗粒气溶胶，理解黑碳气溶胶及关键成分在不同类型污染天气的粒径、浓度、形态、结构等分布特征。利用光腔衰荡激光光谱仪（CRDs）、三波长浊度计（Nephelometer）在线测量气溶胶消光和散射系数，准确计算光吸收系数、单次散射反照率和折射指数。在此基础上，综合单颗粒物表征、总颗粒物相信息及气溶胶光学参数，分析污染大气气溶胶光学特性，阐明黑碳气溶胶质量浓度、混合态、表面结构对气溶胶光吸收强度的影响规律。本项目的顺利实施，有助于准确评估长三角地区气溶胶直接辐射强迫值，全面剖析长三角地区气溶胶、气候变化及区域大气污染之间的本质联系，可为预测全球气候变化提供新的理论线索和依据。

The study on the climate effects of aerosols is focused currently in the forefront fields of atmospheric chemistry and the related areas. This project will take the typical fog-haze pollution of atmosphere as the research background, and take the Yangtze River delta as an example. Single-particle aerosols will be characterized though the coupling of aerosol time-of-flight mass spectrometer (ATOFMS), single particle soot photometer (SP2), and electron microscope (TEM/SEM), to understand distribution characteristics of particle sizes, mixing states, chemical compositions, and surface structures of black carbon aerosols, as well as key components in the different types of atmospheric pollution. Aerosol extinction and scattering coefficient will be measured online with a cavity ring-down laser spectrometer (CRDs) coupled with a nephelometer. Absorption coefficient, single scattering albedo (SSA), and ångström exponent (å) of aerosols can be then calculated precisely. On this basis, single-particle characterization, the information of total particle phase and optical parameters will be considered synthetically, to analyze light absorption properties of aerosols in the pollutant days, and to clarify the influence laws of mass concentrations, mixing states and surface structures of black carbon aerosols on light absorption intension. The smooth implementation of this project will help to assess direct radiation force value of aerosols in the Yangtze River delta region, and to clarify comprehensively the essential relations among aerosols, climate change and regional atmospheric pollution in this region, both of which will provide new clues and evidences for forecasting climate change on the globe.