Ground Truth Studies Teacher Handbook - Aspen Global Change ...

Sources for Remote Sensing Imagery (continued)
U.S. Department of Agriculture, Aerial Photography Field Office in Salt Lake City, part of the Agricultural Stabilization
and Conservation Service (Aerial Photography Field Office, P.O. Box 30010, Salt Lake City, UT 84130; 801-524-
5856), has thousands of aerial photographs covering most of the nation’s major cropland. USDA’s National Forest
Service has aerial photographs of the nation’s forests.
Department of Commerce, National Ocean Service (Distribution Branch, (N/CG33), National Ocean Service, Riverdale,
MD 20737; 301-436-6990) has aerial photographs of the nation’s coastline.
Landsat Images ❖
Landsat images are available for the 50 states and for most of the Earth’s land surface outside the U.S. There are several
products available for any given location, including:
• Single black-and-white images, available as film negatives, film positives, or paper prints.
• Complete sets of four black-and-white images and a false-color composite.
All false-color composites are available as film positives or paper prints.
• Computer tapes containing digital data.
Each Landsat image covers about 8 million acres. Images do not reveal outlines of small areas, like houses or small
towns and villages, but provide views of broad areas and large features, such as mountain ranges and the outlines of
major cities.
Landsat images within the past two years (very expensive— $2,750) are available through EOSAT offices located at the
EROS Data Center (USGS-Department of Interior, EROS Data Center, Sioux Falls, SD, 57198;
605-594-6151), where orders are processed. For images over two years old (much cheaper - $200), order directly from
EROS. When ordering, it is important to describe the exact area in which you are interested, including, if possible, the
geographic coordinates or a map marked with the specific area. You should also indicate:
• The type of product (black-and-white, false-color, or digital tape);
• The minimum image quality acceptable;
• The maximum percent of acceptable cloud cover (10 percent to 90 percent); and
• The preferred time of the year.
A useful brochure, “Landsat Products and Services” is available from the EROS Data Center. This brochure includes a
price list, order form, inquiry form, reference aids, and other information. To order specific images of the 48 contiguous
United States, you can use the form Selected Landsat Coverage (NOAA Form 34-1205, available free from EROS and
USGS Earth Science Information Centers), which includes a map of the U.S. showing the locations of individual Landsat
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© ASPEN GLOBAL CHANGE INSTITUTE 1995 GROUND TRUTH STUDIES