Outputting individual cloud microphysics process rates (source/sink terms) for Thompson and WSM6 in MPAS-Atmosphere

[X1a0wu]

Dear MPAS developers and users,

I am running MPAS-Atmosphere [v7.1] to simulate a [heavy snowfall event], and I would like to diagnose the cloud microphysics budgets of cloud ice, snow, and graupel in detail — for example, the separate contributions from deposition/sublimation, riming, freezing, and melting, similar to the microphysical budget analysis in Ko et al. (2022, GMD). I have been using config_microp_scheme = 'mp_thompson' (and I would also like to do the same with 'mp_wsm6').

So far, I have found the following fields in the Registry, which give the net tendency for each hydrometeor species:

• rqimpten, rqsmpten, rqgmpten (tendency of cloud ice/snow/graupel mixing ratio due to cloud microphysics)
• rthmpten (potential temperature tendency)
• rnimpten, rnrmpten (number concentration tendencies, Thompson only)

These are very useful, but they combine all source and sink processes into a single value. What I need is the individual process terms (e.g., deposition growth of snow, riming growth of graupel, melting of snow/graupel), such as those listed in Table 4 of Ko et al. (2022).

From reading the source code, I understand that these process rates are already computed internally in module_mp_thompson.F (e.g., prs_sde, prg_gde, prs_scw, prg_gcw, ...) and in module_mp_wsm6.F, but they are local variables and are not written to the model output.

Could you please advise:

1. Is there any existing option in MPAS-Atmosphere (namelist, stream field, or compile flag) to output these individual microphysical process rates, or has anyone already implemented such a diagnostic?
2. If not, what would be the recommended (minimal) way to add them? My current plan is to modify the Registry, the microphysics scheme module, the microphysics driver, and the stream file — is that the right approach, and are there any pitfalls to be aware of (e.g., the sub-stepping of the microphysics call)?

Thank you very much for your time.

Best regards