ETOPO2 Global 2-Minute Gridded Elevations

ETOPO2 is a gridded database of bathymetry and land topography covering the entire surface of the earth. Grid cell spacing is 2 arc-minutes. The grids on the GEODAS ETOPO2 CD/DVD set are in the GEODAS Gridded Data Format - GRD98. The GEODAS Software can be used to create custom grids. See Step By Step Instructions for details. The ETOPO2 CD/DVD contains a series of grids covering the entire globe. Each of these CD/DVD grids is a block of 15 degrees by 15 degrees. The files are named according to a NGDC Id file naming scheme.

For more information please see our ETOPO2 web site at www.ngdc.noaa.gov/mgg/fliers/01mgg04.html

Major Sources of Data:

  1. The seafloor data between latitudes 70° North and 72° South are from the work of Smith and Sandwell (1997). These data were derived from satellite altimetry observations combined with carefully, quality-assured shipboard echo-sounding measurements, by Dr. Walter H.F. Smith, of the NOAA Laboratory for Satellite Altimetry and Dr. David T. Sandwell, of the Institute of Geophysics and Planetary Physics at the University of California, San Diego.
    For reference on generation of these data, consult:
    W.H.F. Smith and D.T. Sandwell, "Global Sea Floor Topography from Satellite Altimetry and Ship Depth Soundings," Science Magazine, vol. 277, issue 5334, 1997.
  2. Seafloor data southward of 72° South are from the US Naval Oceanographic Office's (NAVOCEANO) Digital Bathymetric Data Base 5-minute (DBDB5). Seafloor data northward from 70° North are from the new International Bathymetric Chart of the Arctic Ocean (IBCAO).
    For reference on generation of the IBCAO data, consult:
    Jakobsson,M., N.Z. Cherkis, J. Woodward, R.Macnab, and B. Coakley. New grid of Arctic bathymetry aids scientists and mapmakers; Eos,Transactions, American Geophysical Union, v.81, no.9, p. 89,93,96.
  3. Land topography is from the GLOBE Project, an internationally designed, developed, and independently peer-reviewed global digital elevation model (DEM), at a latitude-longitude grid spacing of 30 arc-seconds (30"). The GLOBE Task Team was established by the Committee on Earth Observation Satellites (CEOS). It is part of Focus I of the International Geosphere-Biosphere Programme - Data and Information System. Primary contributors to the GLOBE database are:

Also see our products page offering data on CD/DVDs, posters, slides, and other media.

Or try our on-line viewer showing the same data set as globes from different views

NGDC can produce custom images, on request, for many of our databases. Please contact Dr. Peter W. Sloss (Peter.W.Sloss@noaa.gov), NOAA/NGDC Mail Code E/GC3, 325 Broadway, Boulder, CO USA 80305, Phone 303-497-6119, fax 303-497-6513, for details.

ETOPO2 images were generated from digital data bases of seafloor and land elevations on a 2-minute latitude/longitude grid (1 minute of latitude = 1 nautical mile, or 1.852 km). Assumed illumination is from the west; shading is computed as a function of the east-west slope of the surface with a nonlinear exaggeration favoring low-relief areas. A Cylindrical Equidistant projection was used for the world image, which spans 360 degrees of of longitude from 180 West eastward to 180 East; latitude coverage is from 90 degrees North to 90 degrees South. The resolution of the gridded data varies from true 2-minute for the Atlantic, Pacific, and Indian Ocean floors and all land masses to 5 minutes for the Arctic Ocean floor. Clicking on a square above brings up a 512 x 512 pixel color relief image of the 45 degree area selected, clicking on the 512 x 512 image brings up the full-resolution 1350 x 1350 pixel (roughly 3 mb) color image of the area.