Like :file:`geoschem_config.yml`, information about the :file:`HEMCO_Config.rc` file is the same as for GEOS-Chem Classic with a few exceptions. Refer to the HEMCO documentation for an overview of the file.
Some content of the :file:`HEMCO_Config.rc` file is ignored by GCHP. This is because MAPL ExtData handles file input rather than HEMCO in GCHP.
Items at the top of the file that are ignored include:
- ROOT data directory path
- METDIR path
- DiagnPrefix
- DiagnFreq
- Wildcard
In the BASE EMISSIONS section and beyond, columns that are ignored include:
- sourceFile
- sourceVar
- sourceTime
- C/R/E
- SrcDim
- SrcUnit
All of the above information is specified in file :file:`ExtData.rc` instead with the exception of diagnostic prefix and frequency. Diagnostic filename and frequency information is specified in :file:`HISTORY.rc`.