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刘强、梁顺林与合作者在IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING发表论文
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Direct-Estimation Algorithm for Mapping Daily Land-Surface Broadband Albedo from MODIS Data
Ying Qu, Qiang Liu, Shunlin Liang, Fellow, IEEE, Lizhao Wang, Nanfeng Liu, and Suhong Liu
School of Geography, Beijing Normal University, Beijing 100875, China; State Key Laboratory of Remote Sensing Science, Jointly Sponsored by Beijing Normal University and Institute of Remote Sensing Applications of Chinese Academy of Sciences, Beijing 100875, China; College of Global Change and Earth System Science, Beijing Normal University, Beijing 100875, China; Institute of Remote Sensing Applications, Chinese Academy of Sciences, Beijing 100875, China; Department of Geography, University of Maryland, College Park, Maryland, USA.
ABSTRACT Land surface albedo is a critical parameter in surface-energy budget studies. Over the past several decades, many albedo products are generated from remote-sensing data sets. The Moderate Resolution Imaging Spectroradiometer (MODIS) bidirectional reflectance distribution function (BRDF)/Albedo algorithm is used to routinely produce eight day (16-day composite), 1-km resolution MODIS albedo products. When some natural processes or human activities occur, the land-surface broadband albedo can change rapidly, so it is necessary to enhance the temporal resolution of albedo product. We present a direct-estimation algorithm for mapping daily land-surface broadband albedo from MODIS data. The polarization and directionality of the Earth's reflectance-3/polarization and anisotropy of reflectances for atmospheric sciences coupled with observations from a Lidar BRDF database is employed as a training data set, and the 6S atmospheric radiative transfer code is used to simulate the top-of-atmosphere (TOA) reflectances. Then a relationship between TOA reflectances and land-surface broadband albedos is developed using an angular bin regression method. The robustness of this method for different angular bins, aerosol conditions, and land-cover types is analyzed. Simulation results show that the absolute error of this algorithm is ~ 0.009 for vegetation, 0.012 for soil, and 0.030 for snow/ice. Validation of the direct-estimation algorithm against in situ measurement data shows that the proposed method is capable of characterizing the temporal variation of albedo, especially when the land-surface BRDF changes rapidly.
KEY WORDS: Angular bin regression, direct-estimation algorithm, land-surface broadband albedo, Moderate Resolution Imaging Spectroradiometer (MODIS), polarization and directionality of the Earth’s reflectance (POLDER) bidirectional reflectance distribution function (BRDF) database
PUBLISHED BY: IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING, 2014, 52 (2): 907-919.
SOURCE: http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=6514500&tag=1 |
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