Global GIS Raster Warning:

For the Global GIS product to make use of this dataset some processing was done to the original raster data. ArcView Data Publisher cannot query image pixel values. To overcome this problem a compromise was made. We created a 0.1 by 0.1 point file to store the image pixel values. Thus any values obtained from this method are approximate. For example, you may wish to query the exact top of a mountain peak for its' elevation. If this point does not fall exactly at a 0.1 x 0.1 degree point the value returned back to the user will be from the closest point. The value will not be as precise as the original dataset. The Shaded Relief was created by merging the GTOPO30 and Bathymetry from SCRIPPS digital elevation models (DEM), shading the DEM, and adding color based on the elevation values. Thus in a few areas, water maybe shown for land and land for water. This process was done in Arc/Info by Paul Schruben and Trent Hare from the U.S. Geological Survey.

(Inserted by Trent Hare)

Global 30-Arc-Second Elevation Data Set

More Information: GTOPO30 Readme

Bathymetry from SCRIPPS

Table of Contents

Identification Information
Spatial Reference Information
Distribution Information
Metadata Reference Information

1. IDENTIFICATION INFORMATION


CITATION Publication Date:1996 Title:Global 30-Arc-Second Elevation Data Set Geospatial Data Presentation Form:Model Publication Information
Publication Place:Sioux Falls, South Dakota Publisher:U.S. Geological Survey 

DESCRIPTION
     Abstract:     

     Digital elevation model (DEM) data are sampled arrays of surface
     elevations in raster form.  A DEM provides elevation values in
     rows and columns, corresponding to a regular grid of points on
     the Earth's surface.  The Global 30-Arc-Second Elevation Data Set
     (GTOPO30) is so named, because the spacing between adjacent elevation
     points is 30 arc-seconds (approximately 1 kilometer) of latitude and
     longitude.
     
     Completed in 1997, the GTOPO30 data set was developed at the
     U.S. Geological Survey's EROS Data Center over a 3-year period
     with support from several national and international cooperators.
     Using eight data sources, a global 30-arc-second DEM resulted from
     this cooperative effort.
     
     The GTOPO30 data are suitable for many regional and continental
     applications, including climate modeling; continental-scale land
     cover mapping; extraction of drainage features for hydrologic
     modeling; and geometric and atmospheric correction of medium- and
     coarse-resolution satellite image data.
     
     The Global Land Information System (GLIS) and the EOSDIS Information
     Management System (IMS) are interactive query systems providing
     information on this data set and on a variety of other data sets.
     These systems also support data visualization and ordering services.
     For more information about these systems, see the following home pages:
     
     GLIS Home Page:  http://edcwww.cr.usgs.gov/
     EDC DAAC Home Page:  http://edcdaac.usgs.gov/

     References:
     
     Gesch, D.B., and Larson, K.S., in press, Techniques for
     development of global 1-kilometer digital elevation models,
     in Pecora Thirteen, Human Interactions with the
     Environment--Perspectives from Space, 13th, Sioux Falls, South
     Dakota, August 20-22, 1996, Proceedings:  Bethesda, Maryland,
     American Society of Photogrammetry and Remote Sensing.
     
     Verdin, K.L., and Jenson, S.K., 1996, Development of
     continental scale DEMs and extraction of hydrographic
     features, in National Center for Geographic Information
     and Analysis (NCGIA) International Conference/Workshop on
     Integrating GIS and Environmental Modeling, Third, Sante Fe,
     New Mexico, January 21-25, 1996, Proceedings, CD-ROM,
     1 disc. [Disc contains a Readme file.]


SUPPLEMENTAL INFORMATION:
     Sources:
          DEM > Digital Elevation Model






SPATIAL DOMAIN
     Bounding Coordinates:
          West Bounding Coordinate:180W
          East Bounding Coordinate:180E
          South Bounding Coordinate:90S
          North Bounding Coordinate:90N

STATUS
Dataset Progress: COMPLETE 

KEYWORDS
     Theme Keyword Thesaurus:
          GCMD Parameter Keywords
     Theme Keywords:

          EARTH SCIENCE  >LAND SURFACE  >TOPOGRAPHY  >CONTOURS  >

          EARTH SCIENCE  >LAND SURFACE  >TOPOGRAPHY  >LANDFORMS  >

          EARTH SCIENCE  >LAND SURFACE  >TOPOGRAPHY  >RELIEF  >

          EARTH SCIENCE  >LAND SURFACE  >TOPOGRAPHY  >SURFACE ROUGHNESS  >

          EARTH SCIENCE  >LAND SURFACE  >TOPOGRAPHY  >TERRAIN ELEVATION  >
          ANALYSIS
          DAAC
          DEM
          DIGITAL ELEVATION MODEL
          DIGITAL MAPPING
          DIGITAL TERRAIN ELEVATION DATA
          DTED
          EARTH
          EDC
          ELEVATION DATA
          EOSDIS
          EROS
          MODEL
          RASTER DATA
          SCAR
          SLOPE
          TOPOGRAPHY
          USGS
     Place Keyword Thesaurus:
          GCMD Location Keywords

     Place Keywords:
          AFRICA
          ANTARCTICA
          ASIA
          AUSTRALIA
          EUROPE
          GLOBAL
          NORTH AMERICA
          SOUTH AMERICA


ACCESS CONSTRAINTS
  
  None


USE CONSTRAINTS
  
  None


POINT OF CONTACT
     Contact Person:INFORMATION SYSTEMS MANAGEMENT,PLEASE CONTACT
     Contact Position: DIF Author

     Address:
     
     Information Systems Management
     U.S. Geological Survey
     EROS Data Center
     47914 252nd Street
     Sioux Falls, SD  57198-0001
     USA
     

     Telephone:605-594-6594
     Electronic Mail Address:CUSTSERV@EDCMAIL.CR.USGS.GOV

6. DISTRIBUTION

DISTRIBUTOR
     Contact Organization Primary:EDC_DAAC > EROS Data Center Distributed Active Archive Center
     Contact Person:EDC DAAC USER SERVICES,PLEASE CONTACT
     Address:
     
     EDC DAAC User Services
     U.S. Geological Survey
     EROS Data Center
     47914 252nd Street
     Sioux Falls, SD  57198-0001
     USA
     
     Telephone:605-594-6116
     Electronic Mail Address:EDC@EOS.NASA.GOV
DISTRIBUTOR
     Contact Organization Primary:EROS > Earth Resources Observation Systems Data Center
     Contact Person:CUSTOMER SERVICES,PLEASE CONTACT
     Address:
     
     Customer Services
     U.S. Geological Survey
     EROS Data Center
     47914 252nd Street
     Sioux Falls, SD  57198-0001
     USA
     
     Telephone:605-594-6151
     Electronic Mail Address:CUSTSERV@EDCMAIL.CR.USGS.GOV

STANDARD ORDER PROCESS:

 
     Digital Form:CD-ROM
          Digital Transfer Information:
               Format Name: ISO 9660
               Transfer Size:.5 gigabyte uncompressed
          Fees:$0

     Digital Form:File Transfer Protocol
          Digital Transfer Information:
               Format Name: Raw
               Transfer Size:25 megabyte maximum, compressed
          Fees:$0

     Digital Form:Tape
          Digital Transfer Information:
               Format Name: 8 mm, Tar High Density
               Transfer Size:3 gigabyte maximum
          Fees:$0

     Online Transfer Option:
          Network Address:
               Network Resource Name: http://edcdaac.usgs.gov/
     Offline Medium:Magnetic Tape

7. METADATA REFERENCE INFORMATION

METADATA REVIEW DATE:1997-07-03

[EMAIL ICON]

Responsible NASA Official: Lola Olsen, Code 902, olsen@gcmd.gsfc.nasa.gov
Need Help? Contact: GCMD User Support
Last Updated June 1999