NED (by Anders): 30 meter resolution, unprojected.
Identification_Information:
Citation:
Citation_Information:
Originator: U.S. Geological Survey (USGS), EROS Data Center
Publication_Date: 1999
Title: National Elevation Database
Edition: 1
Geospatial_Data_Presentation_Form: raster digital data
Publication_Information:
Publication_Place: Sioux Falls, SD
Publisher: U.S. Geological Survey
Online_Linkage: http://edcnts12.cr.usgs.gov/ned/ned.html
Description:
Abstract:
The U.S. Geological Survey has developed a National Elevation Database
(NED). The NED is a seamless mosaic of best-available elevation data.
The 7.5-minute elevation data for the conterminous United States are the
primary initial source data. In addition to the availability of
complete 7.5-minute data, efficient processing methods were developed
to filter production artifacts in the existing data, convert to the NAD83
datum, edge-match, and fill slivers of missing data at quadrangle seams.
One of the effects of the NED processing steps is a much-improved base
of elevation data for calculating slope and hydrologic derivatives.
Purpose:
Geospatial elevation data are utilized by the scientific and resource
management communities for global change research, hydrologic modeling,
resource monitoring, mapping, and visualization applications.
Supplemental_Information:
Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 19990201
Ending_Date: Unknown
Currentness_Reference: publication date
Status:
Progress: In work
Maintenance_and_Update_Frequency: As needed
Spatial_Domain:
Bounding_Coordinates: area1
West_Bounding_Coordinate: 121.000
East_Bounding_Coordinate: 117.000
North_Bounding_Coordinate: 38.000
South_Bounding_Coordinate: 35.000
Keywords:
Theme:
Theme_Keyword_Thesaurus: GCMD Parameter Keywords
Theme_Keyword: EARTH SCIENCE
Theme_Keyword: LAND SURFACE
Theme_Keyword: TOPOGRAPHY
Theme_Keyword: LANDFORMS
Theme_Keyword: TERRAIN ELEVATION
Theme_Keyword: 1-DEGREE DEM
Theme_Keyword: 2-ARC-SECOND DEM
Theme_Keyword: 7.5-MINUTE DEM
Theme_Keyword: CARTOGRAPHY
Theme_Keyword: DEM
Theme_Keyword: DIGITAL ELEVATION MODEL
Theme_Keyword: DIGITAL MAPPING
Theme_Keyword: EDC
Theme_Keyword: EROS
Theme_Keyword: GEODATA
Theme_Keyword: GIS
Theme_Keyword: MAPPING
Theme_Keyword: RASTER
Theme_Keyword: USGS
Place:
Place_Keyword_Thesaurus: GCMD Location Keywords
Place_Keyword: NORTH AMERICA
Place_Keyword: UNITED STATES
Place_Keyword: UNITED STATES OF AMERICA
Access_Constraints: None
Use_Constraints:
None. Acknowledgement of the originating agencies would be appreciated
in products derived from these data.
Spatial_Data_Organization_Information:
Direct_Spatial_Reference_Method: Raster
Distribution_Information:
Distributor:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Customer Services Representative
Contact_Organization: EROS Data Center
Contact_Address:
Address_Type: mailing and physical address
Address:
U.S. Geological Survey
EROS Data Center
City: Sioux Falls
State_or_Province: SD
Postal_Code: 57198
Country: USA
Contact_Voice_Telephone: 605-594-6151
Contact_Facsimile_Telephone: 605-594-6589
Contact_Electronic_Mail_Address: custserv@edcmail.cr.usgs.gov
Resource_Description: National Elevation Database (NED)
Distribution_Liability:
Although these data have been processed successfully on a computer
system at the U.S. Geological Survey, EROS Data Center, no warranty
expressed or implied is made by either regarding the utility of the
data on any system, nor shall the act of distribution constitute any
such warranty. The USGS will warrant the delivery of this product in
computer-readable format and will offer appropriate adjustment of
credit when the product is determined unreadable by correctly adjusted
computer peripherals, or when the physical medium is delivered in
damaged condition. Requests for adjustments of credit must be made
within 90 days from the date of this shipment from the ordering site.
Metadata_Reference_Information:
Metadata_Date: 19990211
Metadata_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Customer Services Representative
Contact_Organization: EROS Data Center
Contact_Address:
Address_Type: mailing and physical address
Address:
U.S. Geological Survey
EROS Data Center
City: Sioux Falls
State_or_Province: SD
Postal_Code: 57198
Country: USA
Contact_Voice_Telephone: 605-594-6151
Contact_Facsimile_Telephone: 605-594-6589
Contact_Electronic_Mail_Address: custserv@edcmail.cr.usgs.gov
Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata
Metadata_Standard_Version: FGDC-STD-001-1998
Description of source data:
NED tiles are stored as arc/info grids. Each tile covers a 1x1 degree area of
the earth's surface.
Example grid name: dem10148
10148 refers to the longitude (-101) and latitude (48) of the upper-left
(northwest) corner of the grid.
Example Grid information: dem10148
Cell size: one arc-second
Data type: Floating Point
Number of rows: 3600
Number of columns: 3600
Projection: Geographic
Datum: NAD83
Units: Decimal Degrees
Zunits: Meters
Contents of this CD:
The root directory of the CD contains one README text file and one or more
subdirectories. An example
CD root ----|
|---README - The readme ASCII text file.
|---area - Data directory.
|---demgrid - Arc/Info elevation grid.
|---info - Arc/Info "info" directory.
|---metadata - Arc/Info coverage of polygon-based metadata.
VIEWING Tiles:
No software for viewing NED tiles are included on this disc. Free software for
viewing other USGS digital cartographic data are available at the following
internet sites:
dlgv32 is Windows95/NT software for viewing a variety of USGS geospatial data
including GeoTIFF Tiles.
http://mcmcweb.er.usgs.gov/viewers/dlg_view.html
Arc Explorer is a free lightweight GIS data explorer developed by ESRI.
http://www.esri.com/software/arcexplorer/index.html
PCI Freeware Handler is an application for viewing, enhancing and examining
remotely sensed imagery such as LANDSAT, SPOT, RADARSAT, ERS-1, NOAA AVHRR,
aerial photography. The Freeware Handler is freeware, and is offered by PCI to
the remote sensing community as a public service.
http://www.pcigeomatics.com/downl.html#FREEWARE