How to import the Digital SAR Mosaic of Greenland into ArcGIS

These are directions for importing the grnlnd_dem_wgs84.dat (a flat binary with a 2-byte integer) into ArcGIS.

1. Rename the above file to include a .bsq (band-sequential) file extension (Ex. grnlnd_dem_wgs84.bsq).

2. In the same file directory as the bsq in Step 1, use the following .hdr file:

nrows 1226
ncols 1084
nbands 1
nbits 16
layout bsq
byteorder I
ulxmap -75.00000000
ulymap 84.00000000
xdim 0.06
ydim 0.02

Make sure to name the header file, the same as the bsq file from Step 1 (Ex. grnlnd_dem_wgs84.hdr)

3. Start ArcMap and open ArcToolbox. Select Conversion Tools > To Raster > Raster to Other Format. The Raster to Other Format window will appear. In the Input Raster box, browse and select an EASE-Grid data file with a .bsq extension (Refer to Step 1.). In the Output Workspace box, select the location to store the new data set. In the Output Format box, select the format to create the new data set; this can be one of three formats: ESRI Grid, ERDAS Imagine, or TIFF. Click OK.

4. In ArcToolbox, under Data Management Tools select Projections and Transformations > Define Projection. In the window that appears, select the newly created grid (Refer to Step 3.) as the input data set. Next, select the button next to the coordinate system box. In the window that appears select Select... > Geographic Coordinate System > World > WGS_1984.prj and finally click Add.

5. The data will range from 0-65527. Since the DEM data is a 16 bit-signed integer, the data needs to be formatted that way. In ArcGIS, open up the ArcToolBox > Go to Spatial Analyst Tools > Map Algebra >Multi Output Map Algebra. In the new input box, type the following command in the Map Algebra Expression box (Please use filename from Step 3 and use the full path name for where the file is stored):

newfilename = con(filename >= 32768, filename - 65536, filename)

Click OK.

***New for ArcMap 10 - you do not need to do the map algebra step any longer.  Modify the header file to include "pixeltype signedint" and the data will be formatted correctly.

nrows 1226
ncols 1084
nbands 1
nbits 16
pixeltype signedint
layout bsq
byteorder I
ulxmap -75.00000000
ulymap 84.00000000
xdim 0.06
ydim 0.02 

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The following changes should be made to the above directions, when trying to import the grnlnd_dem_osu91a.dat into ArcGIS.

*User the following header file:

nrows 1251
ncols 1301
nbands 1
nbits 16
layout bsq
byteorder I
ulxmap -75.00000000
ulymap 84.00000000
xdim 0.05
ydim 0.02

* Use the following projection file:

In ArcToolbox, under Data Management Tools select Projections and Transformations > Define Projection. In the window that appears, select the newly created grid (Refer to Step 3.) as the input data set. Next, select the button next to the coordinate system box. In the window that appears select Select... > Geographic Coordinate System > Spheriod_based > OSU 1991 geoidal model.prj and finally click Add.