Development of the Adjoint Model of a Canopy Radiative Transfer Model for Sensitivity Study and Inversion of Leaf Area Index
Development of the Adjoint Model of a Canopy Radiative Transfer Model for Sensitivity Study and Inversion of Leaf Area Index
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DOI：
10.1109/tgrs.2008.916637
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发表时间：
2008-06
影响因子：
8.2
通讯作者：
J. Qin;S. Liang;Xiaowen Li;Jindi Wang
中科院分区：
文献类型：
--
作者：
J. Qin;S. Liang;Xiaowen Li;Jindi Wang
在过去的几十年里，许多冠层反射率模型已经被开发出来，并用于通过优化程序从卫星观测数据中估计陆面生态物理变量，如叶面积指数（LAI）。在大多数研究中，冠层反射率模型的导数信息没有得到有效利用，这限制了该方法的区域和全球应用。最终解往往收敛到局部极小值。为了解决这些问题，在这项研究中，通过自动微分技术的冠层辐射传输模式的伴随模式。开发的伴随模型用于敏感性研究，并结合伴随模型与信赖域全局优化方法进行检索LAI从增强型专题制图增强（ETM+）。本研究表明，该方法可以可靠地用于反演叶面积指数有效，是适合于全球应用。
Many canopy reflectance models have been developed in the last decades and used for estimating land surface biogeophysical variables, such as leaf area index (LAI), from satellite observations through optimization procedures. In most studies, the derivative information of the canopy reflectance model has not been used effectively, which limits this approach for regional and global applications. The final solutions are often converged to the local minima. To address these issues, the adjoint model of a canopy radiative transfer model is developed in this study through the automatic differentiation technique. The developed adjoint model is used for sensitivity study, and a combination of the adjoint model with the trust region global optimization method is performed to retrieve LAI from the Enhanced Thematic Mapper Plus (ETM+). This study demonstrates that this method can be reliably used for inverting LAI efficiently and is suitable for global applications.