How to import the Bamber Greenland DEM into ArcGIS
Directions for Importing Bamber Greenland DEM, Ice Thickness (thick_5km_corrected), and / or Bedrock Thickness (bed_5km_corrected) into ArcGIS. In this example, we'll bring the Bamber Greenland DEM (surface_5km_corrected) into ArcGIS, but the same methodology applies for importing the Ice Thickness (thick_5km_corrected), or Bedrock Thickness (bed_5km_corrected) files into ArcGIS.
Data product: Greenland 5 km DEM, Ice Thickness, and Bedrock Elevation Grids
1. Download the surface_5km_corrected file for the Bamber Greenland DEM.
2. Open surface_5km_corrected with any text editor (Notepad, TextEdit, VI, etc.) and add the following header to the top of the file:
ncols 301
nrows 561
xllcorner -802500
yllcorner -3402500
cellsize 5000
Save the file as *.txt (e.g., surface_5km_corrected.txt).
3. Open ArcGIS and open ArcToolBox then: expand Conversion Tools → expand To Raster → choose ASCII to Raster. In the ASCII to Raster input box do the following:
Input ASCII raster file: Browse to and select surface_5km_corrected.txt
Output Raster: Rename or use default name
Output Data Type: click the drop down menu and choose Float
Click OK. An upside-down image of Greenland will be added to your map layers.
4. To flip this right-side-up, back in ArcToolBox, expand Data Management Tools → expand Projections and Transformations → expand Raster → choose Flip and populate the following:
Input Raster : Select Output Raster from Step 3
Output Raster : Rename or use default name
Click OK. Your new, properly oriented raster DEM should be added to your map layers.
5. This new raster needs to be assigned a customized North Pole Stereographic Projection. In ArcToolBox, expand Data Management → expand Projections and Transformations → choose Define Projection, and do the following:
Input Dataset or Feature Class: browse to your raster output from Step 4
Coordinate System → click the button to the right of the empty text box which opens the Spatial Reference Properties dialogue box.
- On the (default) XY Coordinate System tab, click the Add Coordinate System button, a globe icon
- Choose New → Projected
- At the top Name field, give this projection a name (e.g. BamberThickness)
- In the Projection section, at the Name dropdown, scroll and choose Stereographic_North_Pole
- Edit the Central_Meridian and Standard_Parallel fields:
- Central_Meridian: -39.00
- Standard_Parallel_1: 71.00
Leave everything else as-is. Click OK to close and save the New Projected Coordinate System dialogue box.
Then, click OK to close and save the Spatial Reference Properties box, and OK to close and save the Define Projection dialogue box. The raster layer now has the correct customized Stereographic North Pole projection defined.