UKCA stash diangostics unavailable in this model version (UKCA not CLASSIC)

Unified Model
1

Hello,

I have requested some section 3, 4 and 5 stash diagnostics in my suite u-ce369 which are not being output because they are ‘not available in this model version’ according to the suite logs. The diagnostics are related to aerosol species removal through dry and wet deposition. I followed cms trac ticket #3172
http://cms.ncas.ac.uk/ticket/3172
which suggests running stashtestmask.STASHTstmskValidate on my suite to identify the cause.

Apprarently the diagnostics are not available because of logical switches that are embedded in the CLASSIC aerosol model component (section 17). But, my suite does not use CLASSIC aerosols, it uses modal aerosol (l_ukca_mode=TRUE) with i_mode_setup=2 and offline-odiant chemistry scheme (i_ukca_chem=Offline Oxidants (BE) (14)) in section 34.

The specific logical switches that prevent the diagnostics from being available are:
l_sulpc_so2
l_soot
l_ocff
l_biomass

and the associated diagnostics are:
3-270 to 3-273
3-396 to 3-398
3-407 to 3-409
4-216
4-219
4-220
4-228
4-229
5-238 to 5-244

I have checked the code for use of l_sulpc_so2 for example, and the only use is associated with the CLASSIC aerosol scheme, including the run_aerosols.F90 subroutine, which is associated with section 17 (CLASSIC).

I think there are logical checks in ukca_set1defs.F90 which assume only CLASSIC aerosols will be used. For example:
UkcaD1Codes(j+13)%item=103 ! SO4 Aitken Mode
UkcaD1Codes(j+13)%len_dim1=row_length
UkcaD1Codes(j+13)%len_dim2=rows
UkcaD1Codes(j+13)%len_dim3=tr_levels
IF ((.NOT. l_sulpc_so2) .OR. l_use_arclsulp) &
UkcaD1Codes(j+13)%required=.FALSE.
UkcaD1Codes(j+14)%item=104 ! SO4 accumulation Mode

If I have followed this through correctly, I think I could add an additional logical option for l_ukca_mode to ukca_set1defs.F90, with additional checks for the value of i_mode_setup to make sure the aerosol species associated with the diagnostic is being emitted. Is that a sensible approach?

Thanks and sorry for the long message!

Leighton

2

Hi Leighton,

As these are CLASSIC diagnostics, not UKCA ones, they won’t be available. Even if you edit the logicals the pipework to make use of them won’t exist. UKCA has its own dry & wet removal diagnostics in section 38 - have you checked there that it has what you need?

The code you’ve found is for use when CLASSIC or the CLASSIC aerosol climatology is on - in this case the heterogeneous chemistry can use the CLASSIC aerosols.

Thanks,
Luke

3

Thanks Luke.

I made a problem out of nothing it seems. I’ll try the section 38 diagnostics.

Cheers,

Leighton