"The U.S. Geological Survey (USGS) and the National
Geospatial-Intelligence Agency (NGA) have collaborated on the
development of a notably enhanced global elevation model named the
Global Multi-resolution Terrain Elevation Data 2010 (GMTED2010) that
replaces GTOPO30 as the elevation dataset of choice for global and
continental scale applications. Since the time GTOPO30 was completed, the
availability of higher-quality elevation data over large geographic areas
has improved markedly. New data sources include global Digital Terrain
Elevation Data (DTED®) from the Shuttle Radar Topography Mission (SRTM),
Canadian elevation data, Spot 5 Reference3D data, and data from the Ice,
Cloud, and land Elevation Satellite (ICESat). GMTED2010 provides a new
level of detail in global topographic data. The GMTED2010 product suite
contains seven new raster elevation products for each of the 30-, 15-,
and 7.5-arc-second spatial resolutions and incorporates the current best
available global elevation data..."
GMTOPO30 is my processed version of the GMTED2010 30" mean-elevation
dataset. The original monolithic DEM is in the proprietary (and horrible)
ESRI Arc/Info Grid format, so I have broken it up into the same 33 tiles as
GTOPO30, formatted as plain 16-bit integer rasters and using the same names,
making it a drop-in replacement. The only notable difference (aside from
improved data) is that the oceans of GMTED2010 have 0 elevation value,
whereas GTOPO30 had NODATA value.
See the data page for unpacking instructions.