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ETOPO5 or Terrain Base, 5' data spacing,
which covers the world in about 20 MB. This data
set covers the entire world with both topography and
bathymetry. It shows only the largest features, and is
suited for looked at continental size regions. There is now a 1'
version of this data, which is 25 times larger, or 460 MB. |
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DTED Level 0 or GTOPO30 or GLOBE or SRTM-30, 30" data spacing.
This covers only elevations over land over the entire
world. This data sets shows moderate sized features, and
is best for looking a large areas within a continent. |
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DTED Level 1 or USGS 1:250,000 DEM, 3" data
spacing. SRTM-3,
similar in scale, in now available anywhere in the world below 60N. |
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USGS 1:24,000 DEM, 30 m spacing. This data set approximates DTED Level 2 with 1"
spacing,
SRTM-1 now available
in the United States, and 1" NED. The
ASTER G-DEM
, available world wide, is this scale. |
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USGS 1:24,000 DEM, 10 m spacing. 1/3" NED is roughly the same scale. |
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1 m LIDAR DSM |