# GRASS Help System

## SOURCES OF DIGITAL DATA

(Information for this section is extracted from the USACERL Technical Report "Sources of Digital Spatial Data," USACERL Technical Report N-88/01/ADA189788).

As applications for GRASS have increased, the ability to develop useful, accurate, and up-to-date digital map layers has become very important. Legal boundaries, roads, hydrography, soils, watersheds, and elevation data are among the map layers commonly developed for GRASS databases.

In this section, major sources of national and/or global digital landscape data, and status, coverage and aquisition information about those sources, are identified. Information is provided on data: format, scale/resolution, coverage, media, costs, and textural descriptions and comments.

This information is needed to assess the cost and time requirements of building a digital database for any specific geographic region. Use of existing digital data sources, rather than construction of new digital data, can result in tremendous savings in both time and money. Also, use of standard sources insures minimum standards for accuracy and quality.

Only national sources are covered. More sources may be available at state agencies such as transportion, environmental, and natural resource management departments. Local planning offices, university geography, urban planning, and civil engineering departments may also provide data.

Further information about specific data sources can be accessed by selecting one of the topic areas listed below:

Defense Mapping Agency data -- DMA data
Earth Observation Satellite Co. data -- EOSAT data
Environmental Protection Agency data -- EPA data
National Climatic Data Center data -- NCDC data
National Cartographic Information Center data -- NCIC data
National Geophyiscal Data Center data -- NGDC data
National Geodetic Information Center data -- NGIC data
National Oceanographic Data Center data -- NODC data
National Technical Information Service data -- NTIS data
Oak Ridge National Laboratory data -- ORNL data
Soil Conservation Service data -- SCS data
Satellite pour l'Observation de la Terre data -- SPOT data
EPA STORET (Water Quality) data -- STORET data
U.S. Bureau of the Census data -- USBC data
U.S. Geological Survey-1 data -- USGS data
U.S. Geological Survey-2 data -- USGS data
U.S. Geological Survey-3 data -- USGS data
U.S. Geological Survey-4 data -- USGS data

Digital Data Cross-Reference
Tabular Data Cross-Reference

GRASS Help

GRASS Documentation

GRASS WWW Home

Please use your browser buttons to navigate this documentation!
Automatically created on: Fri Oct 20 10:09:59 2006