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New member
I'm trying to run core_sw. I successfully built it but, when I try to run it, I get the error:

CRITICAL ERROR: Dimension 'nTracers' required by field 'tracers' was neither read nor defined.

I can''t find how to set nTracers but for now I would be happy to just turn tracers off if that's an option.

Any suggestions?


The MPAS shallow water model hasn't been updated or maintained for some time, and it's generally not supported. However, I think a quick work-around in this case would be to simply hard-wire the 'nTracers' dimension to a value of 1 in the Registry.xml file. In src/core_sw/Registry.xml, you can try changing the definition of the nTracers dimension to look like the following:
                <dim name="nTracers"           definition="1"/>
Then, you will need to completely clean the build of the shallow water core before recompiling.