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NASA Web-Enabled Landsat Data CONUS 30m Composites over Annual Periods V001

NASA’s Web-Enabled Landsat Data (WELD) are generated from composited 30 meter (m) Landsat Enhanced Thematic Mapper Plus (ETM+) mosaics of the United States and Alaska from 2002 to 2012. These products provide consistent data to derive land cover, geophysical, and biophysical products for regional assessments of surface dynamics for effective study of Earth system function. The WELD Conterminous (CONUS) United States Annual (WELDUSYR) products include Top of Atmosphere (TOA) Reflectance and Brightness Temperature, along with the Normalized Difference Vegetation Index (NDVI) generated from Band 3 and Band 4 TOA Reflectance. WELDUSYR is distributed in Hierarchical Data Format 4 (HDF4) ( The WELDUSYR products include the preceding year’s December through the current year’s November. For example, for the year 2007, the product includes data from December 1, 2006 through November 30, 2007. The WELD project is funded by the National Aeronautics and Space Administration (NASA) and is a collaboration between the United States Geological Survey (USGS) Earth Resources Observation and Science (EROS) Center and the South Dakota State University (SDSU) Geospatial Sciences Center of Excellence (GSCE).

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