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file on tape. The resulting colors replicate those other
wise achieved at USGS using open-window plate negatives,
conventional mechanical screens, and the same four process
ink colors. These differences in the two dot systems are
visible only under a hand lens. Other differences are
more easily detected, but result chiefly from cosmetic
changes. The square-dot version in brighter colors on
coated paper was printed by the contractor in time for use
in the preliminary EIS, but it lacks the area measurement
table in the later version. The conventionally angled dot
version in somewhat softer colors on conventional USGS map
paper does contain the area measurement table, and is more
nearly to scale. It is the version used in the final EIS
and the CRREL report, and is the only one distributed by
the USGS Western Distribution Branch. Black-and-white
versions at scales of 1:250,000 and 1:1,000,000 have also
been produced as byproducts of the laser printer without
further reprocessing of the data base in the computer.
The data file can also be viewed and further analyzed on
interactive video display equipment in a research labora
tory at USGS.
The production of this map demonstrates a succession of
five stages of automated thematic cartography applied in a
problem-solving context: (1) capture of spatial data in
multispectral format by sensors aboard Earth-orbiting
satellite; (2) interpretation and classification of spatial
data; (3) geometric transformation of the spatial data;
(4) area measurement of classes by areas specified by the
user; and (5) conversion of the spatial data to yet another
multispectral format for map publication by four-color
process printing.
Preparation of the Arctic NWR Vegetation and Land Cover
Map was made possible by the collaboration of three
agencies. The results appear in their separate publica
tions. Authorship of the vegetation and field review are
by William Acevedo (Technicolor Government Services,
serving the National Aeronautics and Space Administration
Ames Research Center) and Donald Walker (University of
Colorado, Institute of Arctic and Alpine Research, under
the sponsorship of the U.S. Army Corps of Engineers Cold
Regions Research and Engineering Laboratory). Design of
map and statistical products is by Leonard Gaydos and
James R. Wray (U.S. Geological Survey). The USGS effort
was augmented by staff and facilities of the Eastern
Mapping Center, the Western Mapping Center, the EROS Data
Center, one contractor, and the headquarters staff of the
National Mapping Division's Office of Geographic and
Cartographic Research.
The arctic map is one more step in a continuing effort to
apply emerging technologies to pressing environmental
problems and the need for increasingly responsive ways to
manage Earth resources. Foreseeable future operational
and developmental efforts include the following: (1)
preparation of interim maps of vegetation and land cover
by standard map quad in northern Alaska as part of a
nationwide inventory; (2) preparation of a larger scale
special vegetation map of a drilling site area west of