[BUG/ISSUE] Incorrect units for ProdLoss diagnostic output in GEOS-Chem 13.0.0+

[msulprizio]

@ltmurray wrote:

The units output by default into the ProdLoss NetCDF diagnostics for the family and individual species production and loss rates have recently changed from molecules cm-3 s-1 to kg s-1.
The model documentation indicates that these units should still be molecules cm-3 s-1 and the values themselves appear to still be in those units.
Was there a conscious attempt to change the units, or is this is a typo introduced into the diagnostics code?

This is a bug in the diagnostics code. The units of the ProdLoss diagnostic are still in molecules cm-3 s-1. In routine Get_Metadata_State_Diag in Headers/state_diag_mod.F90 there is a check for isFullChem using a logical from Headers/diaglist_mod.F90. The bug is in the code that determines the value of isFullChem:

       ! Find out if this is a full-chemistry simulation
       IF ( INDEX( Line, 'Simulation name' ) > 0 ) THEN
          CALL StrSplit( Line, ':', SubStrs, N )
          SELECT CASE( To_UpperCase( ADJUSTL( SubStrs(2) ) ) )
             CASE( 'ACIDUPTAKE', 'APM',              'BENCHMARK',            &
                   'COMPLEXSOA', 'COMPLEXSOA_SVPOA', 'HEMCO',                &
                   'MARINEPOA',  'RRTMG',            'STANDARD',             &
                   'TROPCHEM',   'TOMAS12',          'TOMAS15',              &
                   'TOMAS30',    'TOMAS40'                                  )
                IsFullChem = .TRUE.
             CASE DEFAULT
                IsFullChem = .FALSE.
          END SELECT
       ENDIF

In GEOS-Chem 13.3.0, the input files for all full-chemistry simulations were consolidated so that the simulation names listed above were replaced with a single "fullchem" option but this code was not updated so isFullChem was always false. To fix the units saved out to the netCDF file, we need to change those lines to:

       ! Find out if this is a full-chemistry simulation
       IF ( INDEX( Line, 'Simulation name' ) > 0 ) THEN
          CALL StrSplit( Line, ':', SubStrs, N )
          SELECT CASE( To_UpperCase( ADJUSTL( SubStrs(2) ) ) )
             CASE( 'FULLCHEM' )
                IsFullChem = .TRUE.
             CASE DEFAULT
                IsFullChem = .FALSE.
          END SELECT
       ENDIF

This bug impacts ProdLoss diagnostic files saved out by GEOS-Chem 13.3.0-13.3.0. We will fix it in 13.3.1.

[msulprizio]

This bug is now fixed in commit b1f0206, which will be included in 13.3.1.

[yantosca]

Also see PR #978