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Interpretation, compilation and field verification procedures in the CARETS project

January 1, 1975

The production of the CARETS map data base involved the development of a series of procedures for interpreting, compiling, and verifying data obtained from remote sensor sources. Level II land use mapping from high-altitude aircraft photography at a scale of 1:100,000 required production of a photomosaic mapping base for each of the 48, 50 x 50 km sheets, and the interpretation and coding of land use polygons on drafting film overlays. CARETS researchers also produced a series of 1970 to 1972 land use change overlays, using the 1970 land use maps and 1972 high-altitude aircraft photography. To enhance the value of the land use sheets, researchers compiled series of overlays showing cultural features, county boundaries and census tracts, surface geology, and drainage basins. In producing Level I land use maps from Landsat imagery, at a scale of 1:250,000, interpreters overlaid drafting film directly on Landsat color composite transparencies and interpreted on the film. They found that such interpretation involves pattern and spectral signature recognition. In studies using Landsat imagery, interpreters identified numerous areas of change but also identified extensive areas of "false change," where Landsat spectral signatures but not land use had changed.

Publication Year 1975
Title Interpretation, compilation and field verification procedures in the CARETS project
DOI 10.3133/70039600
Authors Robert H. Alexander, Peter W. De Forth, Katherine A. Fitzpatrick, Harry F. Lins, Herbert K. McGinty
Publication Type Report
Publication Subtype USGS Unnumbered Series
Series Title Final Report
Series Number Volume 5
Index ID 70039600
Record Source USGS Publications Warehouse
USGS Organization Geography Program