This data set includes a selection of urban areas in the United States derived from the urban areas layer of the Digital Chart of the World (DCW). This is a revised version of the 1998 data set. Only minor corrections have been made.
These data are intended for geographic display and analysis at the national level, and for large regional areas. The data should be displayed and analyzed at scales appropriate for 1:2,000,000-scale data. No responsibility is assumed by the U.S. Geological Survey in the use of these data. For use with the GEOSTAC database, this data set has been compiled in order to simplify pesticide risk assessment and to provide a common data set for interested parties.
publication date
None. Acknowledgment of the National Atlas of the United States of America and (or) the U.S. Geological Survey would be appreciated in products derived from these data.
897 B Harrison St SE
National Atlas of the United States of America and the U.S. Geological Survey <http://nationalatlas.gov/atlasftp.html>
No additional checks for topological consistency were performed on this data set.
This data set contains urban areas for the 50 United States.
spatial and attribute information
spatial information
spatial and attribute information
spatial information
spatial information
Urban polygons from the Digital Chart of the World (DCW) CD-ROM were extracted and converted to Arc/INFO format. Where the urban boundaries extended beyond the shoreline of ATLAS-STATES, the shoreline was matched to the ATLAS-STATES shoreline. Names of the urban areas were added using names in ATLAS-CITIES98. In large metropolitan areas many smaller areas were labeled as part of the metropolitan area. The State in which the urban area is located was also added. Several areas were modified to conform to the 1:2,000,000-scale hydrography (ATLAS-HY) layer. Some smaller polygons that represent undeveloped areas within the urban area were removed and merged with the larger urban area. Military reservations were also removed. Finally, the attribute for State FIPS was added.
The spellings for San Francisco, CA and Bismarck, ND were corrected.
Data set projected to NAD 83 and Albers Equal Area.
Data set converted to geodatabase feature class format.
Data aggregated using the ArcGIS geoprocessing Tool, DISSOLVE, in which all non-ArcGIS assigned attribute fields were used, in order to reduce duplicate data.
Dataset copied.
The 2-digit FIPS code of the State or State equivalent. Where the urban area falls in more than one State, the codes are separated by dashes: 11-51-24.
U.S. Geological Survey
The representation of the entity in the data.
U.S. Geological Survey
A 2-dimensional element.
ESRI GIS software
Internal feature number.
ESRI
Length of feature in internal units.
ESRI
The name of the urban area.
U.S. Geological Survey
The 2-character FIPS code of the State or State equivalent. Where the urban area falls in more than one State, the codes are separated by dashes: DC-VA-MD.
U.S. Geological Survey
Area of feature in internal units squared.
ESRI
1500 Research Parkway, Suite B223
In addition to the address above, there are other ESIC offices throughout the country. A full list of these offices is at <http://mapping.usgs.gov/esic/esic_index.html>.
None
Data can be downloaded from www.geostac.org with a registered user ID and password provided by the Spatial Sciences Laboratory.
Not Applicable
897-B Harrison Street, SE