Knowledge Base
How to import the sea ice trends data into ArcGIS
The following are instructions describing how to import Sea Ice Trends and Climatologies from SMMR and SSM/I-SSMIS binary files into ArcGIS. These instructions were tested with ArcMap 10.5 and 10.6.
1. Rename the Data File.
In order to be able to import a Polar Stereographic sea ice trends and climatology file into ArcGIS, you will need to:
Rename the file extension, changing it from .n to .bil
Example: mean.apr.1979-2011.n to mean.apr.1979-2011.n.bil
2. Create a Header File.
In a text editor, create a new file with the content below. You will need to give the file the same name as the data file, but with a .hdr extension. Make sure that the .bil file and the .hdr file are saved in the same folder and are accessible to ArcGIS.
Content of the header file for Northern Hemisphere data:
nrows 448
ncols 304
nbands 1
nbits 8
layout bil
byteorder I
ulxmap -3837500
ulymap 5837500
xdim 25000
ydim 25000
Content of the header file for Southern Hemisphere data:
nrows 332
ncols 316
nbands 1
nbits 8
layout bil
byteorder I
ulxmap -3937500
ulymap 4337500
xdim 25000
ydim 25000
3. Convert the .bil File to an ESRI Compatible Grid Format.
Start ArcMap and open the ArcToolbox. Select Conversion Tools > To Raster > Raster to Other Format (multiple).
In the dialogue box that opens, select your .bil file as the Input Raster.
In the Output Workspace field, select the location to store the new data file. Choose ESRI Grid, ERDAS Imagine, or TIFF as the output raster format.
Click OK. The program will use your .hdr file to define your input raster and create a new, ESRI-compatible file.
4. Define the Projection.
In ArcToolbox, navigate to Data Management Tools > Projections and Transformations > Define Projection.
In the dialogue box that opens, choose your .bil file as the Input Dataset or Feature Class.
Locate Projected Coordinate System > Polar > NSIDC Sea Ice Polar Stereographic [North/South].
Run the tool.
Last Updated December 2019