地面和机载多角度观测数据的反照率反演及对MODIS反照率产品的初步验证

Initial Validation of MODIS Albedo Product by Using Field Measurements and Airborne Multiangular Remote Sensing Observations

MODIS的反照率产品采用半经验的二向性反射核驱动模型算法(AMBRALS),对16天累积观测的多角度遥感数据进行反演。产品的应用需要相关研究的地面观测数据进行验证。主要研究基于地面气象台站用反照率表观测的反照率数据、地面和机载多角度遥感数据通过AMBRALS算法反演得到的反照率,与MODIS相应的地面反照率产品做比较的降尺度验证方法,并提供对MODIS反照率产品的初步验证结果。

With the launch of NASA’s Terra satellite and Moderate Resolution Imaging Spectroradiometer (MODIS),operational Bidirectional Reflectance Distribution Function (BRDF) and albedo products are now providing new opportunity to scientific community.The MODIS BRDF/Albedo algorithm makes use of a semiempirical kernel-driven bi-directional reflectance model to lnverse the albedo by multiangle remote sensing data acquired within 16 days. These products include directional hemispherical albedo (black-sky albedo),bihemispherical albedo (white-sky albedo), Nadir BRDF-Adjusted surface Reflectance (NBAR), model parameters describing the BRDF,and extensive quality assurance information. There has been some validation result for this work,but further validation based on field measurement is also needed to widen application.This work aim to compare the albedo acquired by albedo meter in meteorological station and inverted by field measurement and air-borne MAR data using Kernel-driven model with that of MODIS.The initial validation result is also given in this paper.