Research Opportunities in Geography at the U.S. Geological Survey (2002) / Chapter Skim
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4 Priorities for Geographic Information Science
4 Priorities for Geographic Information Science
Pages 65-82
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From page 65... ...
Second, these general GIScience topics must be addressed if the USGS is to successfully produce an entire range of map products in new digital formats. PRIMARY PRIORITIES The National Map Developing The National Map is the most important single initiative in the Geography Discipline at the USGS (USGS, 2001b)
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From page 66... ...
. Creation of The National Map involves much more than simply digitizing the current topographic maps; it requires a seamless geospatial database that has information from individual topographic maps restructured to achieve the goal of a map without edges.
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From page 67... ...
: · high-resolution digital orthorectified imagery; high-resolution surface elevation (topographic) digital data; vector feature data including hydrographic data, transportation data, structures, and boundaries.
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From page 68... ...
The committee observes that there is no well-developed tradition of such interdisciplinary cooperation involving geography on large projects such as The National Map, but these intra-agency connections will be vital to a successful product. The Cooperative Topographic Mapping program should have primary responsibility for the implementation and maintenance of The National Map, both challenging tasks that require research and development of new GIScience.
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From page 69... ...
as a platform for the compilation and orientation of information from other datasets. Traditionally the USGS has produced Orthorectified imagery of much of the United States from 1 :80,000-scale National High Altitude Photography program imagery, 1 :40,000-scale National Aerial Photography program imagery, or high-resolution imagery from satellites (Figure 4.1~.
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From page 70... ...
The USGS's current National Elevation Dataset (NED) is one of the most important datasets required for producing The National Map.
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From page 71... ...
Improvement and refinement of a comprehensive national elevation dataset should be a high priority, and research is needed to guide this effort. GIScience research is also needed to improve data integration algorithms for fusing the data from multiple agencies and for cleaning existing digital terrain data, which are prone to error accumulation during compilation.
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From page 72... ...
land cover dataset for assessing water quality, ecosystem health, wildlife habitat, land cover, and land management issues (Figure 4.31. The NLCD was derived from 30m Landsat Thematic Mapper imagery and other ancillary data from the early 1 990s, but significant research needs remain to be addressed.
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From page 73... ...
Ice and Snow ~ Bare Ft~kJSand/Ctay 3_ Deciduous Forest _ Evergmen forest Mixed Forest ~ Sh~bland Q;~; Grass~ndlide~aceous O Pasture ~ Hay Row Crops _ Small Grains _ Orchar~Vineyard _ Fat ow _ Quarries |_ Urban Recreational Grasses Woody Wetlands [Emergent Herbaceous Wetlands Low uneasily Resi~nt~al jj~jj High Intens ty Residential _ CommencalllndustriallTransps~tat~n Transitional FIGURE 4.3 An example map created Dom data in the USGS National Elevation Dataset: a three-dimensional image of the Colorado Central Front Range near Denver, land use and land cover. SOURCE: USGS Front Range InDastructure Resources Project; Data Source: USGS National Landcover Database (30 meter resolution)
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From page 74... ...
Other types of supportive research required for land cover contributions to The National Map include improving change detection methods, developing error assessment mechanisms for the various classes of land cover, and making the data more accessible for general users by improving reporting. Biogeographic Data Data on flora and fauna along with their distributions should be included in The National Map.
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From page 75... ...
These data are among the most needed components of the nation's data infrastructure. Linkage of geospatial transportation data to GPSs has stimulated automation and increased efficiency in emergency response, freight and mail delivery, and many other commercial routing applications.
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From page 76... ...
As a result of rapid changes such as high-way modification and load-bearing capacity, it is unlikely that the USGS will be able to update its own transportation database quickly enough to provide real-time data but will depend on acquisition of these data from other agencies or from private sources. For these reasons, the USGS should begin developing partnerships and promoting data standards for the transportation data needed in The National Map.
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From page 77... ...
One example is the National Land Cover Dataset (NLCD) , which must use the most appropriate resolution for each region of the nation rather than a uniform resolution for all regions regardless of complexity.
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From page 78... ...
Transmitting geospatial data via the Internet has become commonplace, usually using raster data that is efficient for imagery, orthophotography, and satellite data products. Transmission proceeds incrementally: transmitting ll
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From page 79... ...
Standards for GIS Products Standards for geospatial products address data lineage, accuracy, the compilation sources, the processing methods, and the chronology of processing, as well as error and uncertainty. The elements of standards for geospatial data are positional and attribute accuracy, completeness, logical consistency, and lineage.
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From page 80... ...
The USGS should conduct research on how to model spatial variation in error, how error is introduced into geographic information during data processing, and under what circumstances error may be reduced by particular computations. Research underlying the development of data standards includes many components of data production that at first seem unimportant.
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From page 81... ...
Second, USGS personnel must possess substantial analytical capability to address the Survey's vision and mission, both heavily reliant on spatial data. Spatial analysis uses transformations and statistical manipulations to identify trends, reveal patterns, and detect outliers or extreme values.
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From page 82... ...
The National Map is expected to be the flagship product of the Geography Discipline in the next decade. However the accomplishment of this worthy goal is not assured with present knowledge.
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