中国地区气溶胶散射对短波近红外CO2遥感探测影响研究

项目名称： 中国地区气溶胶散射对短波近红外CO2遥感探测影响研究

项目编号： No.41501373

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： 范萌

作者单位： 中国科学院遥感与数字地球研究所

项目金额： 20万元

中文摘要： 短波近红外波段由于对近地层CO2浓度的变化更为敏感而成为CO2探测的首选。然而，由于短波近红外通道观测数据受气溶胶和卷云的散射影响显著，而我国又是颗粒物污染较为严重的区域，因此，研究中国地区这种复杂的高浓度复合型污染大气情况下的气溶胶散射对CO2遥感探测的影响具有十分重要的意义和实际参考价值。针对气溶胶粒子的复杂性，本研究基于已有的气溶胶粒子电镜扫描分析结果对中国地区气溶胶粒子进行分类建模，并利用T矩阵、GMM等方法计算每类气溶胶粒子的散射特性参数。为解决高颗粒物浓度情况下导致的气溶胶多次散射加剧问题，本研究基于蒙特卡洛随机方法构建气溶胶多次散射模型，然后将其与LBLRTM进行耦合作为大气辐射传输正向模型，并结合气溶胶粒子的散射特性参数研究气溶胶散射对短波近红外CO2浓度遥感探测的影响。

中文关键词： 气溶胶；散射；蒙特卡洛；CO2探测

英文摘要： For the application of remote sensing techniques to monitor CO2 concentrations, measurements using short wave infrared (SWIR) band are more sensitive to the changes of CO2 concentrations in boundary layer of atmosphere compared with data using thermal infrared (TIR) band. Therefore, SWIR channels (~1.6 μm) are selected for space-based remote sensing of CO2. However, one challenge for the satellite measurements of CO2 using this SWIR wavelength range is the impact of multiple scattering by aerosols and cirrus. Since the rapid economic growth and associated increase in fossil fuel consumption have caused serious particulate pollution in many regions of China, remote sensing of CO2 using SWIR band in China needs to pay more attention to the scattering properties of aerosol particles and the multiple scattering. Considering the complexity of morphological and chemical properties, aerosol particles are grouped based on a large number of TEM/SEM images, and then their scattering properties at 1.6 μm band are calculated by the T-matrix method and GMM method. The Monte Carlo method is used to solve the multiple scattering problem by simulating photons transport in the scattering media. We combined this multiple scattering model with the LBLRTM as a forward radiative transfer model for studying the impact of aerosol scattering on the satellite observations of CO2 using SWIR band.

英文关键词： Aerosol;Scattering;Monte Carlo;Remote sensing of CO2