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Writing new EROD to geogrid

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New member
I have produced new EROD grids from soil surveys via GEOTIFF. I have used gdal_translate, but since erod as three bands, I run into issues. I can either get one band in and the file is okay (but still unacceptable to geogrid, maybe because it lacks a Z dimension?), or using -b 1 -b 2 -b 3, I get a file that is not anything close to what it should be, usually checkered (I used all the banding options [BSQ/BIP/BIL]). What is the best way to write new binary files for geogrid that have a z dimension?
I assume that you have already read about, and tried to follow the procedure described in the WRF Users' Guide (, but I just want to verify.

When you say that with one band the file is unacceptable to geogrid, what type of error are you getting? Can you send attach the namelist.input file you're using, along with your geogrid.log, and let me know which version of the WPS you are using?
Yes. I am using WPSV4.1.2. I guess the single band data did work through WPS, but it does fail in WRF (again, likely because the data it is overriding is three-dimensional, not two). I don't see much in the way of any documentation anywhere about how to handle three-dimensional data when writing to the binaries for input to geogrid, and this is what I am after. EROD data appears to have three dimensions, unlike any other WPS input data I have found (two of which appear to be duplicates of data which already exists in higher resolution within wrf/wps already!). I guess before we dive into my log files at any specific problems I have, I am more interested to know how one is supposed to generate the 3D input binaries.
When writing 3-d fields for ingest by the geogrid program, you'll essentially write each of the layers (months of the year, physical layers, parameters for the field, etc.) one after another, writing each to the file as you would write a 2-d field. So, for example, if you had a field with two layers (A and B) that looked like the following in memory:
A[4,1] A[4,2] A[4,3] A[4,4]
A[3,1] A[3,2] A[3,3] A[3,4]
A[2,1] A[2,2] A[2,3] A[2,4]
A[1,1] A[1,2] A[1,3] A[1,4]
B[4,1] B[4,2] B[4,3] B[4,4]
B[3,1] B[3,2] B[3,3] B[3,4]
B[2,1] B[2,2] B[2,3] B[2,4]
B[1,1] B[1,2] B[1,3] B[1,4]
in which A[1,1] and B[1,1] were at the south-west corner of your dataset, you would write the values A[1,1] ... A[4,4] B[1,1] ... B[4,4] to the file, which in this example might be named 00001-00004.00001-00004.
Hello, I am also trying to do similar work with you. I have tested and modified EROD in many areas, but the EDUST changes in the results are not obvious. May I ask whether your modification of EROD has a great impact on the results?
Haopeng Zhang
We didn't run such test cases, and I am sorry that I don't have an immediate answer yo your question.
But wold you please clarify that with the changes you made, you did see some impacts on the model results?
if you make some radical changes in erod, can you see significant impacts on the result? Thanks.