动态气溶胶模型的PARASOL多角度偏振卫星气溶胶光学厚度反演算法  

Dynamic model in retrieving aerosol optical depth from polarimetric measurements of PARASOL

作　　者：陈澄[1,2] 李正强[1] 侯伟真[1] 李东辉[1] 张玉环[1,2] 

机构地区：[1]中国科学院遥感与数字地球研究所国家环境保护卫星遥感重点实验室,北京100101 [2]中国科学院大学,北京100049

出　　处：《遥感学报》2015年第1期25-33,共9页NATIONAL REMOTE SENSING BULLETIN

基　　金：中国科学院科技创新重点部署项目(编号:KGFZD-125-13-006);中国科学院创新团队项目(编号:KZZD-EW-TZ-09)

摘　　要：在卫星气溶胶反演中,如何确定研究区域的气溶胶模型直接影响目前大多数卫星遥感算法的气溶胶光学厚度反演精度。本文基于气溶胶自动观测网(AERONET)典型类型的动态气溶胶模型,提出了一种基于动态气溶胶模型的气溶胶光学厚度反演算法,并将其运用到PARASOL(Polarization and Anisotropy of Reflectance for Atmospheric Science coupled with Observations from Lidar)卫星的反演中。针对华北地区2012年的PARASOL卫星观测数据,应用动态气溶胶模型反演算法反演气溶胶光学厚度,并与地面观测站点进行对比验证,结果显示通过气溶胶模型选取与反演结果的迭代约束,在865 nm反演的气溶胶光学厚度与地基观测的相关程度(R2)达到0.71,均方根误差(RMSE)为0.15,与PARASOL气溶胶产品相比一定程度提高了反演结果的精度。In the satellite aerosol retrieval scheme, determining the aerosol model directly affects the accuracy of most of the current aerosol optical depth retrieval algorithms. The dynamic aerosol models determined based on the extensive analysis of aerosol optical properties obtained from AErosol RObotic NETwork （AERONET） sun-photometer observations are introduced to a new aerosol retrieval algorithm to derive the Aerosol Optical Depth （AOD） using the PARASOL （Polarization and Anisotropy of Reflectance for Atmospheric Science coupled with Observations from LiDAR） multi-angular and polarimetric measurements. The rationale of our algorithm is to initially establish LUTs （Look Up Tables） using dynamic aerosol models in ten different AOD conditions： Model AODE[0.0, 0.1], [0.1, 0.2], [0.2, 0.3], [0.3, 0.5], [0.5, 0.8], [0.8, 1.0], [1.0, 1.23, E1.2, 1.53, 1.5, 1.8 ], and [ 1.8, 2.0 ]. The retrieved AOD and selected aerosol model must meet two requirements successively ： （ 1 ） combination of the retrieved AOD and Model that leads to the best mimic of the TOA （ Top Of Atmosphere） polarized reflectance measurements; （2） the retrieved AOD in the Model AOD intervals, otherwise the retrieved AOD and the Model will be rejected. The accuracy of this algorithm is guaranteed by the iterative constraint between the aerosol model selection and the retrieved AOD, as well as the simultaneous use of two bands （670 nm and 865 nm）, multiangular, and polarimetric measurements to constrain the retrievals. By applying this algorithm to a whole year of the 2012 PARASOL measurements in the North China Plain, typical cases, such as clean and polluted days, were analyzed to test this algorithm. The validation of the retrieved PARASOL AOD with those of AERONET in Beijing showed reasonable agreement （matched pairs N = 101, square correlation coefficient R2 = 0.71, root mean square error RMSE =0.15, and 91% of all the samples lie within 0.2 AOD thresholds）. To validate the regional suitability of this algorithm,

关 键 词：AERONET 动态气溶胶模型 多角度 偏振 气溶胶反演 

分 类 号：X513[环境科学与工程—环境工程] X87