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E3SM-Project / v3atm

Fork of E3SM for testing v3 atm changes
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add flag for stratosphere wateruptake treatment #31

Closed keziming closed 1 year ago

keziming commented 1 year ago

This PR contain two targets: Firstly, set a name list variable as a flag to turn on/off the treatment for stratospheric H2SO4 water uptake. This treatment is a new future as part of MAM5 but it may contribute to up to 3% of the total computational cost. For production run in general, this function can be turned off. The impact on longterm simulation is minor. For studies related to stratospheric chemistry, this feature may be useful. The default setting is to turn off stratospheric H2SO4 water uptake treatment and treat water uptake in the whole atmosphere same.

Secondly, set a automatic switch between MAM5 and prescribed cmip6 volcanic treatment. MAM5 is the new feature for the V3 and it treats volcanic emission interactively. If MAM5 is chosen in the configuration, the prescribed cmip6 volcanic treatment can be turned off automatically. This can let the atm_in setting easier. Currently, we need to manually set prescribed volcanic data path to "" to avoid that function activated, which could be an issue for people outside aerosol area.

I hope this PR can be merged into NGD_v3atm to let model run faster and easier to setup. The additional tests are on the way and the change of model output should be minor.

mingxuanwupnnl commented 1 year ago

@keziming For the change in prescribed_volcaero.F90, it seems hard wired to me. I would suggest setting a flag in namelist. Or just setting them to null as we do for now.

keziming commented 1 year ago

@mingxuanwu For people outside of aerosol, it is likely to forget 'null' the prescribed_volcaero, when using MAM5. At least this setting automatically turn it off while has no impact on any setting without MAM5. You are right, I can change it to a namelist, such as "volcanic SO2 emission flag" latter.

wlin7 commented 1 year ago

Merged to NGD_v3atm.