JP3.28
Daily Albedo and Reflectance Anisotropy Products
Crystal B. Schaaf, Center for Remote Sensing, Boston University, Boston, MA; and M. Román, Q. Zhang, Y. Shuai, A. Strahler, D. Roy, G. Anderson, and J. L. Privette
Global albedo and reflectance anisotropy products have now been operationally available from the MODIS instruments on board the Terra and Aqua satellite platforms for almost nine years. Intrinsic Albedo measures, Bidirectional Reflectance Distribution Function (BRDF) model parameters, and Nadir BRDF-Adjusted Reflectances (NBAR) are provided every 8 days at a 500m resolution for seven spectral bands and three broadbands. They are based on all high-quality, multi-spectral, cloud-free, atmospherically-corrected, directional surface reflectances which are available over a multi-day period and which adequately model the surface anisotropy.
These products are used by a number of environmental monitoring and modeling efforts and a daily version of the algorithm has also been implemented for regional use with direct broadcast data. The daily algorithm relies on frequent periodic multi-date retrievals of the surface BRDF in combination with the directional surface reflectances available on any particular day. The daily NPOESS albedo algorithm is partially based on this heritage and with the advent of expanded multi-spectral GOES-R data, the opportunity will exist to utilize directional data (with varying solar and view angles) from both the national polar orbiting and geostationary platforms. Use of data from multiple platforms (as is currently achieved with Aqua and Terra) increases the opportunity for sufficient cloud-free observations and thus results in more high-quality retrievals of the surface anisotropy. Several field validation efforts and satellite product intercomparisons have been accomplished to date under the auspices of the CEOS/WGCV/Land Product Validation (LPV) Albedo Subgroup. Results from validations of the daily algorithm using MODIS and MSG data (as surrogates for NPOESS and GOES-R) will be presented.
Joint Poster Session 3, Npoess
Tuesday, 13 January 2009, 9:45 AM-11:00 AM, Hall 5
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