Extended Abstract (308K)P5.21
Land Surface Albedo, Nadir BRDF-Adjusted Reflectance, and BRDF Products from the MODerate Resolution Imaging Spectroradiometer (MODIS)
Crystal B. Schaaf, Boston University, Boston, MA; and F. Gao, A. H. Strahler, W. Lucht, X. Li, X. Zhang, Y. Jin, E. Tsvetsinskaya, J. -. P. Muller, P. Lewis, M. Barnsley, G. Roberts, C. Doll, S. Liang, D. Roy, and J. L. Privette
Provisional albedo and bidirectional reflectance products of the Earth's land surfaces from the MODerate resolution Imaging Spectroradiometer (MODIS) on board NASA's Terra spacecraft have been available since November 2000. Atmospherically corrected, cloud cleared, surface reflectances are used to produce MODIS Bidirectional Reflectance Distribution Function (BRDF), Nadir BRDF-Adjusted surface Reflectance (NBAR), and Albedo Products (MOD43B1, MOD43B3 and MOD43B4) every 16 days. The operational MODIS BRDF/Albedo algorithm relies on multidate data and a semiempirical kernel-driven bidirectional reflectance model (RossThickLiSparseReciprocal) to determine a global set of parameters describing the BRDF of the land surface. These one kilometer gridded parameters are then used to determine global directional hemispherical reflectance ("black-sky albedo"), and bihemispherical reflectance ("white-sky albedo") for the first seven spectral bands of MODIS and three broad bands of interest to modelers. The parameters are also used to obtain the Nadir BRDF-Adjusted surface Reflectances (NBAR) for the seven spectral bands (at the mean solar zenith angle of the period). Due to their stability, the NBAR data are subsequently used to serve as the primary input for the MODIS Land Cover Product (MOD12Q1). The BRDF, NBAR and Albedo Products are all being evaluated by the science team and and a number of validation field exercises are now underway. These provisional data sets are publically available from the EDC DAAC.
Supplementary URL: http://geography.bu.edu/brdf/userguide/index.html
Poster Session 5, New Technology and Methods
Wednesday, 17 October 2001, 2:15 PM-4:00 PM
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