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Natural Earth. DEM2TOPO Generator. DEM2TOPO is a program to generate vector contour levels from freely available digital elevation model (DEM) data.

DEM2TOPO Generator

These contour vectors are ideally suited for upload to portable GPS units where commercial topographic maps are unavailable or inadequate. With a few simple steps and the appropriate software, topo maps can be uploaded to Garmin GPS units that support mapping (see the Using DEM2TOPO section, below). The program is designed for Canadian DEM files , but those for other countries using the ASCII version of the USGS DTED file format should work.

GeoTIFF files are also supported, but currently only those written by 3DEM have been tested. The Canadian Digital Elevation Data (CDED) consists of an ordered array of ground elevations at regularly spaced intervals. DEM2TOPO is written in IDL, which is a high level interpreted language for scientific data analysis. Download the prebuilt RT version. Using DEM2TOPO License agreement Send feedback The program is beerware. DEM Discovery Portal Map. ETOPO1 Global Relief. ETOPO1 is a 1 arc-minute global relief model of Earth's surface that integrates land topography and ocean bathymetry.

ETOPO1 Global Relief

It was built from numerous global and regional data sets, and is available in "Ice Surface" (top of Antarctic and Greenland ice sheets) and "Bedrock" (base of the ice sheets) versions. Historic ETOPO2v2 and ETOPO5 global relief grids are deprecated but still available. NCEI has utilized the ETOPO1 Global Relief Model to calculate the volumes of the world's oceans and to derive a hypsographic curve of Earth's surface. Color Image of Earth A color shaded-relief image of Earth from ETOPO1 Ice Surface, created by NGDC (now NCEI), is displayed above. Atlantic-centered and Pacific-centered wall posters of ETOPO1 are now available. Available Versions of the Grid ETOPO1 Ice Surface: Grid of Earth's surface depicting the top of the Antarctic and Greenland ice sheets.ETOPO1 Bedrock: Grid of Earth's surface depicting the bedrock underneath the ice sheets.

Horizontal Datum Custom Grids. DEM Global Multi-resolution Terrain Elevation Data 2010. The U.S.

DEM Global Multi-resolution Terrain Elevation Data 2010

Geological Survey (USGS) and the National Geospatial-Intelligence Agency (NGA) have released an updated and more accurate global elevation model that pulls data from Digital Terrain Elevation Data (DTED®) from the Shuttle Radar Topography Mission (SRTM); Canadian elevation data; SPOT 5 Reference 3D data; data from NASA’s Ice, Cloud, and land Elevation Satellite (ICESat); and updated Antarctica and Greenland terrain models. This new elevation data called Global Multi-resolution Terrain Elevation Data 2010 (GMTED2010), replaces the thirty year old GTOPO30 terrain model.

GMTED2010 is a suite of seven raster data products: minimum elevation, maximum elevation, mean elevation, median elevation, standard deviation of elevation, systematic subsample, and breakline emphasis. The spatial resolution of GMTED2010 ranges from 30, 15 and 7.5 arc-seconds (approximately 1 kilometer, 500 meters and 250 meters, respectively). DEM data. Sources and References Digital elevation data can now be obtained for any place on the earth, at several resolutions.

DEM data

The GTOPO30 global dataset has a 1 km resolution. This dataset is very good for working at the continental scale and with very large regions. SRTM data feature near global coverage at 90 m resolution. This provides consistent global coverage at higher resolution than had been previously available outside of the U.S. CGIAR-CSI SRTM 90m DEM Digital Elevation Database. Getting altitude data. NASA ASTER Data Products. SOSE - Real-Time Satellite Data. SRTM Data Search. Free Satellite Data - TERRAINMAP Satellite Image Analysis. Free Satellite Data, Satellite Imagery, Digital Elevation Models (DEMs), Topographic Maps and free software links.

Free Satellite Data - TERRAINMAP Satellite Image Analysis

Free DEM Data DEM Explorer DEM download site for SRTM, GTOPO and more. USGS Geographic Data Download This is the original USGS data format. Gisdatadepot.com SDTS DEM data format was the USGS attempt at creating a new file format specification. An SDTS DEM is comprised of 18 separate files, arranged in a most unfriendly structure from a processing standpoint. USGS Seamless Data Distribution The next attempt by the USGS took the existing SDTS data and reformatted it into a data structure that allowed the data to be selected by rubber-band box from a map GUI such that DEMs of any arbitrary size could be supplied to the user.