气溶胶光学有效复折射率的数值模拟闭合反演与应用研究

项目名称： 气溶胶光学有效复折射率的数值模拟闭合反演与应用研究

项目编号： No.41505127

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 天文学、地球科学

项目作者： 张小林

作者单位： 南京信息工程大学

项目金额： 21万元

中文摘要： 气溶胶复折射率是计算气溶胶气候辐射效应的必须物理参量，而当前气溶胶-气候模式使用的基于体积混合规律近似的化学有效复折射率，会导致内混合气溶胶辐射特性模拟有很大的不确定性。而基于实际探测光学特性的闭合实验反演的气溶胶光学有效复折射率，由于其与成分、混合态等特征参量的关系及其物理含义的认识仍不足，还没有应用于气溶胶-气候模式。本项目拟对混合态复杂的实际气溶胶粒子进行探测和建模，基于精确计算的散射和吸收特性来闭合反演气溶胶光学有效复折射率，消除粒子形状和探测仪器误差干扰后，探讨其反演规律及其真实物理含义，建立其与粒子谱分布、成分比例和混合方式等特征参量的定量关系；在此基础上构建参数化的典型成分内混合气溶胶光学有效复折射率数据库，并耦合进当前气溶胶-气候模式。该项工作不仅具有重要的学术意义，而且对优化气溶胶-气候模式模拟能力、激光大气传输和辐射传输模式的改善等研究都有重要的应用价值。

中文关键词： 气溶胶；复折射率；闭合反演；数值模拟；气候模式

英文摘要： Aerosol complex refractive index (ACRI) is a must for modeling aerosol radiative effects. The uncertainties in simulating radiative properties of internal-mixed aerosol by aerosol-climate models may stem from the chemically effective ACRI based on volume weighted average approximation. The optically effective ACRI can be determined from closure experiment on the basis of measured aerosol optical properties. However, the optically effective ACRI has not been utilized in aerosol-climate models, since its physically-based meanings and relations with other parameters, such as composition and mixing state, still need to be addressed. The research proposed here simulates complex-mixed aerosols, determines their optically effective ACRI from exactly calculated scattering and absorption properties, with uncertainties in aerosol shapes and property measurements being eliminated. This will describe the theoretical retrieval mechanism and physical meaning of optically effective ACRI, and construct quantitative relations between ACRI and size distribution, composition, and mixing state. The parameterized optically effective ACRI database for internal-mixed particles will also be established for aerosol-climate models. This work is beneficial not only for improving the simulation of aerosol radiative properties by aerosol-climate models, but for studies of laser atmospheric propagation and radiative transfer.

英文关键词： aerosol;complex refractive index;closure study;numerical simulation;climate model