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LandSat Satellite ImageryOverview | Selecting Files | NCSU Landsat Data Holdings Overview
The US Geological Survey (USGS) now offers, at no cost, the entire Landsat archive online (as of December 2008). Orthorectified Landsat data are available for free download from the Global Visualization Viewer (GloVis) at http://glovis.usgs.gov and Earth Explorer at http://earthexplorer.usgs.gov. Additionally, a lot of Landsat and other satellite data may be downloaded for free from the Global Land Cover Facility (GLCF). For more information about the Landsat program and data, see: NCSU Libraries has a collection of select Landsat data as listed below. Unlike earlier Landsat data, there are no restrictions on redistribution. Selecting FilesThe image below shows how the twelve scenes that cover North Carolina overlap. Notice that some locations are covered by as many as four scenes - Stanly County for example.  Click here for a larger version of this image The North Carolina scene index is available as a shapefile in State Plane 1983 (meters) on the Geodata Server at ftp://gisdata.lib.ncsu.edu/landsat7/ or under \landsat7 by mapped drive. NCSU Landsat Data HoldingsNCSU Libraries' Landsat data holdings and may be considered organized into three different batches, some with overlapping dates: Batch 1 was purchased by NCSU Libraries and covers roughly 1999-2000 with both "leaf-on" and "leaf-off" time periods. Batch 2 was given to NCSU Libraries by UNC University Libraries, and includes data for 1984, 1999-2002, and 2004. Batch 3 are multiple scenes from Path 16, Row 35, which spans the Piedmont of North Carolina. One advantage of using these scenes, rather than searching for and downloading data from a data website, is that they have probably already been selected by someone as being cloud-free and of high quality. Also, they will be much easier to acquire than navigating the download websites. Batch 1:"Leaf-off" data is available for winter 1999-2000 and "leaf-on" data is available for 2000 (some 1999). The data is tiled in 12 scenes, identified by Path/Row in GeoTIFF format and in UTM (different zones). The images are radiometrically and geometrically corrected (level 1G product). Path/Row and image dates are indicated in the file name (e.g. L72017035_03520000306_B80.TIF is from Path 17, Row 35, and was taken March 6, 2000). Leaf-off data Leaf-on data Projection: All of these images are in UTM Zone 17 except: Zone 16: Path 19, Row 36 The WGS84 ellipsoid is employed as the Earth model for coordinate transformation. For each scene (path/row) there are 9 TIFF images--one for each band as indicated in the following table:
The last 3 characters of the filename stem (before .TIF) indicate the band. NOTE: Filenames are very long. It may be necessary to shorten the filename to use the data in some software. Batch 2:1984 Data There are 10 Thematic Mapper images from May 19 to August 4, 1984. This set is missing Path 016 Row 035 and Path 017 Row 036 in order to completely cover North Carolina. (There is a confirmed mid 1980s image available from the GLCF website for Path 017 Row 036 that can be downloaded). Spatial resolution-28.5 meters; Format-GeoTIFF; Projection-UTM; Datum-WGS 1984; Units-Meters.
1999-2000 Data There is a full set of 12 Landsat 7 images from 1999-2002 that covers North Carolina. Some of these data images were used to create the 2001 National Land Cover Database for the state. Spatial resolution-30 meters; Format-NLAPS, BSQ; Projection-Albers Conical Equal Area; Datum-NAD 1983; Units-Meters.
2004 Data There are 2 CDs of Landsat 7 ETM+ imagery from July 2004 for Path 16 Row 35, which covers roughly the central Piedmont area of NC excluding the southernmost counties. One image is a scan line corrector (SLC) off image, so it is gappy. Another image was used to fill the gaps. We have both the gappy and gapless images. Spatial resolution-28.5 meters; Format-GeoTIFF; Projection-UTM; Datum-WGS 1984; Units-Meters. Batch 3:This batch of Landsat images were purchased cooperatively by Duke, UNC, and NCSU Libraries. The scenes are all for Path 16, Row 35, which extends from West of the Triad to East of the Triangle, North into southern Virginia, and South into the NC Sandhills. The purpose of this acquisition was a land cover change study at Duke. The imagery is in standard National Land Archive Processing System (NLAPS) Data Format (NDF). Some are also in GeoTIFF format. Contact Data Services to discuss various options for converting these into other formats if needed. The following dates are available on the Geodata Server at ftp://gisdata.lib.ncsu.edu/landsat7/P16R35/ or path \landsat7\P16R35\ by mapped drive.
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