Prosed Plan:
The mass mixing ratios (mmr) in SCREAM atmospheric driver(AD) are “wet” mmr[units: kg-of-specie/kg-of-moist-air]. For each parameterization called by AD, it is the responsibility of the parameterization to convert wet mmr to dry mmr [units: kg-of-specie/kg-of-dry-air](if needed) for its use. The tendencies computed by the parameterization should be converted back to wet mmr before they are passed on to AD. For parameterizations which exclusively use wet mmr, there is no need for any conversion however, for parameterizations which use dry mmr, following steps must be followed:
Interface layer of parameterization should convert wet mmr to dry mmr
Parameterization computes tendencies using the dry mmr internally
Interface layer of the parameterization will then convert the dry mmr tendencies to wet mmr
These wet mmr tendencies are then passed on to AD
SCREAM provide following methods for converting dry mmr to wet mmr and vice versa via functions:
calculate_drymmr_from_wetmmr
calculate_wetmmr_from_drymmr
Volume Mixing ratios (vmr)[units: kmol-of-specie/kmol-of-(dry or moist)-air]:
Some parameterizations may use vmr. For these parameterizations, SCREAM provide the following functions to convert between mmr and vmr (and vice versa):
calculate_mmr_from_vmr
calculate_vmr_from_mmr
vmr can be dry or wet, appropriate conversion should be made based on parameterization requirements. Tendencies computed by the parameterization should be converted back to wet mmr before passing these back to AD.
Type of mixing ratios used by SCREAM parameterization:
P3 - Dry mmr
SCREAM - Dry mmr
HOMME - Wet mmr
RRTMGP - Wet vmr
Tasks:
P3 (uses dry mmr):
- Ensure that P3 converts wet mmr to dry mmr for all constituents in its interface layer
- Ensure that tendencies from P3 are converted back to wet mmr
SHOC [uses dry mmr]:
- Ensure that SHOC converts wet mmr to dry mmr for all constituents in its interface layer
- Ensure that tendencies from SHOC are converted back to wet mmr
RRTMGP [uses wet vmr]:
- Ensure that RRTMGP converts wet mmr to wet vmr
- Ensure that tendencies from RRTMGP are converted back from wet vmr to wet mmr