中高分辨率陆地上空大气气溶胶光学厚度与地表二向性反射率卫星遥感反演研究

项目名称： 中高分辨率陆地上空大气气溶胶光学厚度与地表二向性反射率卫星遥感反演研究

项目编号： No.41501358

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： 李英杰

作者单位： 江苏师范大学

项目金额： 20万元

中文摘要： 地气解耦问题一直是影响陆地光学卫星遥感信息定量化的重点和难点。早期的陆地气溶胶遥感反演算法大都针对浓密植被等暗地表，且忽略了地表的二向性反射特性（BRDF），其结果是反演得到的气溶胶产品的空间分辨率较低，覆盖范围有限，并且存在较大误差。本研究将以30 m分辨率的国产环境卫星CCD数据为主要数据源，充分考虑大气气溶胶和地表二向性反射参数的时空变化特征，通过合理假设来减少未知数的个数，进而利用多天多角度的卫星遥感数据构建大气AOD和地表BRDF联合反演算法。同时，为了提高反演精度，将建立气溶胶模型先验知识库，并对反演结果进行后期处理，以获得具有较高空间分辨率和质量控制的AOD和地表BRDF产品。其中，AOD可用于区域空气质量监测研究，而BRDF则可以精确刻画地物的方向性反射特征，进而可应用于其他地表参数的建模与反演，提高陆地定量遥感应用水平。

中文关键词： 气溶胶；光学厚度；多角度遥感；多光谱遥感；可见光-近红外遥感

英文摘要： It is difficult to separate the contributions of atmosphere and land surface from the satellite optical remote sensing signal, which is the key to improve the level of remote sensing information quantification. The early aerosol retrieval algorithms over land are based on the dark surface covered by the dense vegetation. The surface bidirectional reflectance properties, which are usually described as the bidirectional reflectance distribution functions (BRDF), are ignored. The disadvantages of the algorithms include that the spatial resolution of AOD are very low, the feasibility of the algorithm is so weak over the bright surface such as desert and urban area that the AOD retrieval is much uncertain. In this study, a new synchronous retrieval algorithm will be proposed of the higher spatial resolution (about 30 m) aerosol optical depth over land and the surface bidirectional reflectance distribution function parameters from the multi angular dataset sourced from the China HJ-1A/1B of the Environment and Disasters Monitoring Microsatellite. The basic assumptions are the different spatio-temporal change features of the atmospheric aerosol and the land surface BRDF parameters. Normally, atmospheric aerosols have great changes in the time dimension but little changes in the spatial dimension, which is opposite to the land surface BRDF. According to the assumptions, the time series satellite observations of 30m HJ-1A/1B CCD data over the same area are applied to reduce the number of unknowns and retrieve the AOD and BRDF synchronously by solving the radiative transfer equations with the look-up table. To improve the AOD retrieval accuracy, a prior knowledge database of aerosol model will be established and some post processing will be applied. The AOD with higher spatial resolution and better quality control can be used for the regional environment monitoring and the BRDF can be used for other parameters remote sensing modeling and inversion, in order to improve the level of the land quantitative remote sensing applications.

英文关键词： aerosol;optical depth;muliti-angle remote sensing;muliti-spectral remote sensing;visible and near infrared remote sensing