NASA Web-Enabled Landsat Alaska WELD Tile system over Alaska, United States.View full-size image
The NASA Web-Enabled Landsat Data (WELD) Alaska Latitude Longitude (LL) products are defined with 30 meter (m) composite pixel of the center latitude/longitude point. The NASA WELD data contain a range of values for the minimum/maximum latitude and longitude points. The LL products were created to account for the actual center pixel latitude and longitude points.
WELD systematically generated 30 m composited Landsat Enhanced Thematic Mapper Plus (ETM+) mosaics of the United States and Alaska from 2002 to 2012 to provide consistent data for deriving land cover as well as geophysical and biophysical products for regional assessments of surface dynamics for effective study of Earth system function. WELDAKLL is distributed in Hierarchical Data Format 4 (HDF4).
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).
Version 1.5 is the original version.
|Collection||MEaSUREs WELD and GWELD|
|File Size||~305 MB|
|Temporal Extent||2002-12-01 to 2012-12-31|
|Spatial Extent||Alaska (United States)|
|Coordinate System||Albers Equal Area|
|Datum||World Geodetic System (WGS84)|
|Geographic Dimensions||150 km x 150 km|
|Number of Science Dataset (SDS) Layers||2|
|Columns/Rows||5000 x 5000|
|Pixel Size||30 m|
|SDS Name||Description||Units||Data Type||Fill Value||No Data Value||Valid Range||Scale Factor|
|Longitude||Center Longitude of each 30 m pixel||Degree||64-bit floating point||N/A||N/A||N/A||N/A|
|Latitude||Center Latitude of each 30 m pixel||Degree||64-bit floating point||N/A||N/A||N/A||N/A|
WELD Version 1.5 product quality information can be found in section 6 of the WELD ATBD.
WELD Version 1.5 known issues can be found on the page 21 of the WELD Version 1.5 User Guide.