This data set provides a 100 meter resolution surface topography Digital Elevation Model (DEM) of the Antarctic Peninsula. The DEM is based on Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Global Digital Elevation Model (GDEM) data.
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Antarctic Peninsula 100 m Digital Elevation Model Derived from ASTER GDEM, Version 1
|Temporal Resolution:||Not specified|
|Data Contributor(s):||Allison Cook|
|Metadata XML:||View Metadata Record|
As a condition of using these data, you must cite the use of this data set using the following citation. For more information, see our Use and Copyright Web page.Cook, A. J. 2012. Antarctic Peninsula 100 m Digital Elevation Model Derived from ASTER GDEM, Version 1. [Indicate subset used]. Boulder, Colorado USA. NSIDC: National Snow and Ice Data Center. doi: http://dx.doi.org/10.7265/N58K7711. [Date Accessed].
Detailed Data Description
This data set provides a high-resolution Digital Elevation Model (DEM) of the Antarctic Peninsula.
The DEM is provided in GeoTIFF format and as an ASCII text file.
Table 1 contains the descriptions of the files in the data set.
Final GeoTIFF file.
Ancillary GeoTIFF files
DEM in ASCII text format.
Files are named according to the following convention and as described in Table 2.
File name example:
Digital Elevation Model
Resolution (100 meter)
Data files range in size from 1 KB to 209 MB.
The entire data set is approximately 600 MB.
Northernmost Latitude: 70°S
Southernmost Latitude: 63°S
Westernmost Longitude: 70° W
Easternmost Longitude: 55° W
Projection and Grid Description
Projection: WGS84 Antarctic Polar Sterographic, Standard Parallel -71 deg South.
Grid: Surface elevation model, 1 Band, Continuous, Floating point, 32 Bit, 6164 columns, 8918 rows.
This DEM is based on the ASTER GDEMv1, which uses scenes dating from 2000 to 2009. The dates of all scenes used to generate the GDEM in this region are not specified.
Elevation in meters above the EGM96 Geoid. The EGM96 Geoid is a DEM consisting of elevations above the WGS84 Ellipsoid.
0 to 3172 meters
Software and Tools
Data are readable using standard image processing software.
Data Acquisition and Processing
Data used to created this DEM were modified from the ASTER Global Digital Elevation Model (GDEM).The ASTER GDEM is the most recently released nearly global elevation data set and is based upon a composition of automatically generated DEMs from ASTER stereo scenes acquired from 2000 to the present. It was produced by the Ministry of Economy, Trade and Industry (METI) of Japan and the United States National Aeronautics and Space Administration (NASA). Full details of the methodology for this data set are to be published in Cook, et. al., 2012.
No formal ASTER GDEM validation has been performed over Antarctica, but it is evident that there are significant errors within the tiles throughout the Antarctic Peninsula region, introduced as a direct result of high reflectance and lack of features on snow-covered plateaus. Since conventional data correction techniques do not work in this region, a new approach was used to significantly improve the data set. Processing for the new DEM converted the GDEM into contours and removed the erroneous contours, producing a smooth and realistic new DEM from the remaining contours. This method was applied only to poor-quality regions of the GDEM, and the resulting DEMs were merged with the unaltered high-quality GDEM regions. See Figure 2 for the edited regions. The method is made possible by the fact that the high-artefact regions are those where the real-surface (as observed on the Landsat Image Mosaic of Antarctica [LIMA]) is smooth and has a low slope angle.
ASTER GDEM tiles were downloaded from ASTER GDEM site and mosaicked according to each latitudinal degree across the Antarctic Peninsula. Each mosaic was projected onto a reference system suitable for minimizing distortions in scale and for preserving angles locally. In this case, Lambert Conformal Conic (LCC) projection was used with standard parallels and other parameters according to latitude. The subsequent methodology was then applied separately to each latitudinal degree raster between 63 degrees and 70 degrees South.
Using a Geographic Information System (GIS), contours were generated automatically from the GDEM at 20 m intervals. A new file was then created by digitizing around regions of erroneous contours, based on the GDEM stacking number file and manual corrections using visible band imagery. These "noisy" regions of the DEM were then resampled to 200 m to simplify and remove gross errors, and sinks in the DEM were filled and smoothed. Contours at 20 m intervals were then created for this generalized DEM.
In order to correct these contours a slope model was created and contours that fell within a slope angle of greater than 20 degrees were removed. Secondly, contours less than 1 km in length were deleted, as these came from spikes or pits in the DEM. The surface topography was reconstructed by interpolation between the remaining contours, which represented consistent elevation values between the anomalies. The corrected regions of the DEM were then mosaicked with the remaining high-quality regions to create a topographically consistent DEM. The final step of the process involved reprojecting all tiles to a common reference system (Polar Stereographic projection with a standard latitude of 71 degrees South and a central meridian of 0 degrees), mosaicking all tiles and clipping to remove any remaining artifacts along the coast. The outer limit is based on the LIMA coastline with a 500 m buffer.
The new DEM has a mean elevation difference of - 4 m (±25 m Root Mean Square Error [RMSE]) from ICESat, and a horizontal error of less than 2 pixels, although elevation accuracies are lower on mountain peaks and steep-sided slopes. Some anomalies along the coast have been removed, resulting in small gaps, and the DEM has a small number of remaining artifacts. It only covers regions included in ASTER GDEM, in which there are inherent gaps and some missing islands.
Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) nadir and backward looking sensors. The data set was based on the ASTER Global Digital Elevation Model (GDEM) data.
References and Related Publications
Contacts and Acknowledgments
Alison Cook, Tavi Murray, and Adrian Luckman
Department of Geography
Swansea, SA2 8PP
David G. Vaughan and Nicholas E. Barrand
British Antarctic Survey
High Cross, Madingley Road
Cambridge, CB3 0ET
DOCUMENT CREATION DATE
April 18, 2012