Description
This DEM was processed from the GTOPO30 dataset available at ftp://edcftp.cr.usgs.gov:21/pub/data/gtopo30/global. It is part of the W100N40 tile.
DescriptionThis DEM was processed from the GTOPO30 dataset available at ftp://edcftp.cr.usgs.gov:21/pub/data/gtopo30/global. It is part of the W100N40 tile.
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| The GTOPO30 data provide estimated elevations, in meters, at the centers of unprojected square cells 30 minutes on each side. Using Spatial Analyst this tile was clipped, warped with an order-three polynomial to approximate an Equidistant Conic projection (Clarke 1866 spheroid, central meridian 71 degrees west, reference latitude 19 degrees north, standard parallels at 21 and 17 degrees north), resampled to approximately the same cell size using bilinear interpolation, and rounded to the nearest meter. The resulting grid has 840 rows of 929 columns and a cell size of 927.94 meters. | |
The processed grid was saved in "binary" (single precision floating point file plus a header file) format using Spatial Analyst and zipped. Download the file here.
Unzip the downloaded file into any directory. If you are using Spatial Analyst, choose the File|Import data source option from a View. Select "binary raster" format.
When asked for "output grid," navigate to the folder where you want this grid to be stored. Provide a short DOS name for the grid: that is, choose a name with eight or fewer letters (or numbers--but don't begin the name with a number) and no spaces or special characters.
Spatial Analyst will add the grid to the current view if you choose. Later, you can add it to any view in any ArcView project using the Add Theme button--just make sure to specify a grid data source (see the bottom left corner of the dialog).
If you want to integrate other data with this DEM, you will need to use the same projection used to create it (see description).
