气溶胶谱分布地基反演算法改进研究

项目名称： 气溶胶谱分布地基反演算法改进研究

项目编号： No.41301381

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 天文学、地球科学

项目作者： 蒋哲

作者单位： 中国科学院大气物理研究所

项目金额： 25万元

中文摘要： 研究气溶胶的光学物理特性是认识其对环境质量、气候变化和人体健康影响的基础。掌握气溶胶谱分布将有助于分析气溶胶的来源结构及其动力学过程,直接为治理颗粒物污染提供依据。目前利用地基遥感可见光、近红外的天空散射光和太阳直射光可以反演得到气溶胶谱分布信息，但往往基于单一地表反射率的假设，并且忽略了前向散射的贡献。本项目针对现有地基反演算法存在的不足开展不确定性分析和敏感性实验，并提出以下改进方案： 1）订正太阳直射光信号中的前向散射光的影响； 2）在可见光、近红外通道的基础上引入独立的短波红外光谱信息； 3）地表反射率的确定由先验预估方法改为根据MODIS地表反射率库计算。 基于改进后的算法，本项目拟采用北京地区的PREDE-POM02观测数据进行气溶胶谱分布反演实验，并将反演结果与AERONET、ELPI气溶胶谱分布产品进行对比分析。

中文关键词： 气溶胶；遥感；谱分布；地基反演；

英文摘要： In order to estimate the radiative effect of the atmospheric aerosols oin the climate system, it is of the upmost importance to accurately determine the optical and physical properties of aerosls in the atmosphere. Size distribution information is crucial for understanding the behavior and transformation of aerosols, as well as their influence on the atmosphere. Ground-based networks (such as AERONET and SKYNET) have been established worldwide for studying the columnar properties of aerosol using sun-sky radiometers. The optical depth and size distribution of aerosols can be retrieved by taking sun direct and sky diffuse radiation measurements in both visible and near-infrared bands. In addition, validating aerosol products obtained from various satellite sensors requires ground-based measurements of a variety of aerosol characteristics. Therefore, error analysis and quality assurance of ground-based products is of great importance. To overcome some problems existing in the current ground-based inversion algorithms, we propose to make the following improvement on the data retrieval method: 1) to adopt MODIS surface reflectance database instead of a priori estimates; 2) to add short-wave infrared band observation data; 3) to account for the solar radiation forward-scattered into the field of view of instruments.

英文关键词： aerosol；remote sensing；size distribution；ground-based inversion；