USGS Landsat Analysis Ready Data (ARD) available for download EarthExplorer

Contributed By: Larry Biehl
IndianaView Coordinator
Purdue University, Young Hall 942
155 South Grant Street
West Lafayette, IN 47907-2108
Email: biehl@purdue.edu
Tel: (765) 494-3529

USGS Landsat Analysis Ready Data (ARD) for the conterminous United States are now available for download from EarthExplorer (https://earthexplorer.usgs.gov).  Eventually, Landsat 1-5 Multispectral Sensor (MSS) data will also be included in the ARD product suite once these data have been processed into the Landsat Collection 1 inventory structure.

Landsat ARD is a revolutionary new product that will make the Landsat archive more accessible, easier to analyze, and will reduce the amount of time users spend on data processing for time-series analysis. Landsat ARD are derived from Landsat Collection 1 Level-1 precision and terrain-corrected scenes, which are then processed and arranged in geospatially calibrated tiles and dense temporal stacks for immediate use in monitoring and assessing landscape change.  Each Landsat ARD tile consists of the following four data layers:

  • Top of atmosphere (TA) reflectance
  • Brightness temperature (BT)
  • Surface reflectance (SR)
  • Pixel quality assessment (QA)

Landsat ARD products are processed to a common tiling scheme. Each tile contains 5,000 x 5,000 30-meter pixels, and includes all the pixels acquired in a given day within its extents.

Landsat ARD documentation and other useful resources are located on the Landsat ARD webpage: https://landsat.usgs.gov/ard.

About the USGS/EROS EarthExplorer Imagery Data and Services:

USGS/EROS has digitized over 6.6 million frames of aerial film creating medium-resolution digital images (400 dpi) and associated browse files for on–line viewing and have scanned over 4 million of the same frames at 1,000 dpi. Both the medium and high resolution aerial TIFFs can be downloaded for free from the USGS EarthExplorer web site: https://earthexplorer.usgs.gov/

Film scan requests (for film not yet scanned):

Requests for film scans can be made through EarthExplorer after you identify the frame you need.  Customers can also order higher resolution aerial or Declassified image to be scanned for a $30.00 per frame service fee.

Georeferenced or Geocorrected Scans:

The USGS film scans are not georeferenced or geocorrected.  Film scans are faithful copies of the imagery from the source film. Distortions imposed by the scanners are removed, but no other correction work is done to geo-locate the image scans to ground truth.  The DOQ (digital ortho quad) and High-Resolution Ortho collections may be another data source to consider if you have this requirement.

FILM OPTIONS:

CIR (color infrared) film, originally referred to as camouflage-detection film, differs from conventional color film because its emulsion layers are sensitive to green, red, and near-infrared radiation (0.5 micrometers to 0.9 micrometers). Used with a yellow filter to absorb the blue light, this film provides sharp images and penetrates haze at high altitudes. Color infrared film also is referred to as false-color film.

Black-and-white panchromatic (B/W) film primarily consists of a black-and-white negative material with a sensitivity range comparable to that of the human eye. It has good contrast and resolution with low graininess and a wide exposure range.

Black-and-white infrared (BIR) film, with some exceptions, is sensitive to the spectral region encompassing 0.4 micrometers to 0.9 micrometers. It is sometimes referred to as near-infrared film because it utilizes only a narrow portion of the total infrared spectrum (0.7 micrometers to 0.9 micrometers).

Natural color (also referred to as conventional or normal color) film contains three emulsion layers which are sensitive to blue, green, and red (the three primary colors of the visible spectrum). This film replicates colors as seen by the human eye.

For more information:

USGS/EROS EarthExplorer Frequently Asked Questions (FAQs):  https://lta.cr.usgs.gov/aerialfaq

USGS/EROS EarthExplorer Help: https://lta.cr.usgs.gov/ee_help

Other sources for government film scans:

NASA’s Gateway to Astronaut Photography: http://eol.jsc.nasa.gov

Earth Data Analysis Center: http://edac.unm.edu/

National Archives and Records Administration (NARA): http://www.archives.gov/

Environmental Protection Agency (EPA): http://www.epa.gov/

Aerial Photography Field Office (APFO): http://www.fsa.usda.gov/FSA/apfoapp?area=apfohome&subject=landing&topic=landing

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