作者: Daniel A. Sims , Abdullah F. Rahman , Eric F. Vermote , Zuoning Jiang
DOI: 10.1016/J.RSE.2011.06.018
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摘要: Abstract The bi-directional reflectance distribution function (BRDF) has been widely studied across different vegetation types. However, these studies generally report values for only one point in time. We were interested the potential seasonal and inter-annual variation BRDF parameters. NASA's Moderate Resolution Imaging Spectroradiometer (MODIS) sensor on board EOS satellites now collecting data 10 years. Since parameters are reported individual spectral bands, can be used to examine intra-annual variation. MODIS not calculated various indices which derived from bands. Our objective this study was use 10 years of available view angle sensitivity three indices; normalized difference index (NDVI), enhanced (EVI), photochemical (PRI) at 3 flux tower sites (Harvard Forest, Howland Forest Morgan Monroe State Forest). For sites, EVI significantly affected by angle. There also a substantial seasons backscatter vs. forward scatter data. It is possible that differences scattering radiation between spring fall responsible sensitivity. complimentary variations years. greater EVI, as opposed NDVI, suggests care must taken correct effects when using index.