# `variables.nml`

The `variables` namelist defines the list of CMIP7 variables to be processed. In CMIP7, each entry is a branded variable name stored in the `compound_names` list, following the CMIP7 convention for variable identifiers and brand suffixes.

A typical entry has the form:

```text
<realm>.<variable_id>.<temporal_label>-<vertical_label>-<horizontal_label>-<area_label>.<frequency>.<region>
```

This is the CMIP7 version of the "compound name" used to identify a variable and its sampling/processing context, and it is the metadata basis for the final CMIP7 output naming and DRS.

```fortran
!
! --- --- --- --- --- ---
! list of variables to be cmorized;
! use Fortran comment to activate/deactivate any of themgc
!   'ocean.agessc.tavg-ol-hxy-sea.mon.glb'              ! add note here
! --- --- --- --- --- ---
!
&variables
mapfile         = '../recipes/template/mapping.json',
compound_names  = 
!
    'ocean.agessc.tavg-ol-hxy-sea.mon.glb'
    'ocean.areacello.ti-u-hxy-u.fx.glb'
!...
    'ocean.zos.tavg-u-hxy-sea.day.glb'
    'ocean.zos.tavg-u-hxy-sea.mon.glb'
    'ocean.zossq.tavg-u-hxy-sea.mon.glb'
    'ocean.zostoga.tavg-u-hm-sea.mon.glb'
!
    'ocnBgchem.calc.tavg-ols-hxy-sea.mon.glb'
    'ocnBgchem.chl.tavg-ols-hxy-sea.day.glb'
    'ocnBgchem.chl.tavg-ols-hxy-sea.mon.glb'
!...
    'ocnBgchem.zooc.tavg-ols-hxy-sea.mon.30S-90S'
    'ocnBgchem.zooc.tavg-ol-hxy-sea.mon.glb'
/
```

`mapfile` specify path to the variable mapping file that links model-specific output fields to the CMIP7 data request and target metadata definitions.

The list of compound names denotes the datasets to be CMORized:

| Example compound name | Meaning |
| --- | --- |
| `ocean.agessc.tavg-ol-hxy-sea.mon.glb` | Ocean age scalar with monthly means, using the `ol` vertical label, `hxy` horizontal sampling, `sea` masking, and global region. |
| `ocean.areacello.ti-u-hxy-u.fx.glb` | Fixed-field ocean cell area, with the `fx` frequency and global domain. |
| `ocean.zos.tavg-u-hxy-sea.day.glb` | Sea surface height (dynamic sea level) as daily means over the global ocean. |
| `ocean.zos.tavg-u-hxy-sea.mon.glb` | Same field but monthly mean output, following the CMIP7 branded-variable naming scheme. |
| `ocean.zostoga.tavg-u-hm-sea.mon.glb` | Global ocean steric sea-level anomaly or equivalent monthly mean diagnostic. |
| `ocnBgchem.chl.tavg-ols-hxy-sea.mon.glb` | Ocean biogeochemistry chlorophyll concentration, monthly mean, global ocean domain. |
| `ocnBgchem.zooc.tavg-ols-hxy-sea.mon.30S-90S` | Zooplankton concentration for a specified latitude band, monthly mean, Southern Ocean subset. |

:::{tip}
The entries can be commented out with `!` to disable individual variables without removing them from the file, which makes it easy to re-run only selected CMIP7 diagnostics.
:::