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GMTED2010 elevation data at different resolutions

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Elevation data sets at different resolutions have been compiled from the 15 arc-second resolution GMTED2010 global digital elevation model, aggregated into one file by the team assembling the datasets needed for the TROPOMI data processing, and correction for an error in the GMTED2010 dataset over the Caspian Sea (a large area of that sea has zero elevation instead of -27 m).
Note that there is no special value for ocean waters in these files; the elevation of the ocean water is simply 0 (zero) metres.

The data is given in two formats:

There are several programs around to read & view these datafile, e.g. hdfview (both file types), ncview (netCDF only), panoply (strangely enough does not work on the netCDF files). For data processing, the files can be read with programs such as IDL, Matlab, Maple. Information sources, with examples, tools and software at the The HDF Group:   HDF-5,   netCDF-4,   HDF-4

resolution * nlon nlat netCDF & HDF-4 data files
0.125 degrees 2880 1440 GMTED2010_15n030_0125deg.nc [7.2MB]

GMTED2010_15n030_0125deg.hdf [7.3MB]

0.250 degrees 1440 720 GMTED2010_15n060_0250deg.nc [2.1MB]

GMTED2010_15n060_0250deg.hdf [2.0MB]

0.500 degrees 720 360 GMTED2010_15n120_0500deg.nc [605kB]

GMTED2010_15n120_0500deg.hdf [568KB]

1.000 degrees 360 180 GMTED2010_15n240_1000deg.nc [206bK]

GMTED2010_15n240_1000deg.hdf [170KB]

*) a. A resolution of 0.5 degrees means about 50 kilometer at the equator.
    b. If other resolutions (multiples of 15 arc-seconds = 1/240-th degree)
        are needed, please contact Jos van Geffen.

Official citation of the GMTED2010 elevation data:

Danielson, J.J., and Gesch, D.B., 2011,
Global multi-resolution terrain elevation data 2010 (GMTED2010):
U.S. Geological Survey Open-File Report 2011-1073, 26 p.
[ http://pubs.usgs.gov/of/2011/1073/pdf/of2011-1073.pdf ]
See the official GMTED2010 webpage for more details and background information.


The netCDF and HDF-4 data files

The netCDF data file provides the elevation data in the form of 2-dimensional arrays with the longitude and latitude coordinates given in separate arrays. Since netCDF is based on the HDF-5 format, netCDF files can also be read with HDF-5 readers. The HDF-4 data files give the same data sets (variables), but is organised slightly differently.

The following table gives an overview of the data sets (variables) in a data file.

variable unit dimension(s) 1 description
longitude deg nlon longitude of grid cell centr
latitude deg nlat latitude of grid cell centre
longitude_bounds deg nlon,nbounds longitude of grid cell boundaries
latitude_bounds deg nlat,nbounds latitude of grid cell boundaries
elevation 2 m nlat,nlon altitude above the geoid
elevation_stddev 2 m nlat,nlon standard deviation of the altitude above the geoid
elevation_max 2 m nlat,nlon maximum elevation above the geoid in grid cell
elevation_min 2 m nlat,nlon minimum elevation above the geoid in grid cell
1) The dimensions nlat and nlon depend on the resolution;
    viz. the table at the top of the page.
    The dimension nbounds always equals 2.
2) These four evelation data sets have an attribute giving the
    minimum and maximum value found in the set.

Each of the variables has some attributes, while the file itself has some global attributes (the HDF-4 file has some extra global attributes, following earlier elevation data files provided via TEMIS).

The above data files have been created from a single high-resolution netCDF file created within the TROPOMI project. Attributes from that original input file, used to generate the above files, are given as attributes to a group 'Original_attributes' in the netCDF file and to an otherwise empty variable 'original_attributes' in the NDF-4 file.

The following image shows the map at 0.5 degree resolution (i.e 720x360).

[GMTED2010 elevation at 0.5 degree]


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Page last modified: 24 February 2016