Title
Assessment of MODIS BRDF/Albedo Model Parameters (MCD43A1 Collection 6) for Directional Reflectance Retrieval.
Abstract
Measurements of solar radiation reflected from Earth's surface are the basis for calculating albedo, vegetation indices, and other terrestrial attributes. However, the bi-directional geometry of illumination and viewing (i.e., the Bi-directional Reflectance Distribution Function (BRDF)) impacts reflectance and all variables derived or estimated based on these data. The recently released MODIS BRDF/Albedo Model Parameters (MCD43A1 Collection 6) dataset enables retrieval of directional reflectance at arbitrary solar and viewing angles, potentially increasing precision and comparability of data collected under different illumination and observation geometries. We quantified the ability of MCD43A1 Collection 6 for retrieving directional reflectance and compared the daily Collection 6 retrievals to those of MCD43A1 Collection 5, which are retrieved on an eight-day basis. Correcting MODIS-based estimates of surface reflectance from the illumination and viewing geometry of the Terra satellite (MOD09GA) to that of the MODIS Aqua (MYD09GA) overpass, as well as MCD43A4 Collection 6 and Landsat-5 TM images show that the BRDF correction of MCD43A1 Collection 6 results in greater consistency among datasets, with higher R-2 (0.63-0.955), regression slopes closer to unity (0.718-0.955), lower root mean squared difference (RMSD) (0.422-3.142), and lower mean absolute error (MAE) (0.282-1.735) compared to the Collection 5 data. Smaller levels of noise (observed as high-frequency variability within the time series) in MCD43A1 Collection 6 in comparison to Collection 5 corroborates the improvement of BRDF parameters time series. These results corroborates that the daily MCD43A1 Collection 6 product represents the anisotropy of surface features and results in more precise directional reflectance derivation at any solar and viewing geometry than did the previous Collection 5.
Year
DOI
Venue
2017
10.3390/rs9111123
REMOTE SENSING
Keywords
Field
DocType
directional reflectance,BRDF correction,Moderate Resolution Imaging Spectroradiometer (MODIS),MCD43A1 Collection 6
Bidirectional reflectance distribution function,Meteorology,Satellite,Anisotropy,Remote sensing,Mean absolute error,Albedo,Root mean square,Reflectivity,Directional reflectance,Geology
Journal
Volume
Issue
ISSN
9
11
2072-4292
Citations 
PageRank 
References 
2
0.39
9
Authors
6
Name
Order
Citations
PageRank
Xianghong Che141.44
Min Feng220420.90
Joseph O. Sexton312213.35
Saurabh Channan413614.96
Yaping Yang5175.99
qing sun6487.22