f.e30_cam6_4_127.FHISTC_LTso.ne30.dust_DGLC.001

[cecilehannay]

Purpose:
Testing new dust tunings + lower seasalt emission factor

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Description:

Same as #761 except

• user_nl_cam

dust_emis_fact = 3.4
seasalt_emis_scale = 1.0

• sourcemods

/glade/work/dleung/derecho_cases/dust_tuning/251027_tuning_FHIST_LT_SPmode_asphericalDAODdrydep_newPSD/SourceMods/src.cam/
aero_model.F90  
aerosol_optics_cam.F90  
dust_model.F90  
modal_aero_wateruptake.F90

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Case directory:

• Locally (if still available):
  /glade/campaign/cesm/cesmdata/cseg/runs/cesm2_0/f.e30_cam6_4_127.FHISTC_LTso.ne30.dust_DGLC.001

• On github:
  https://github.com/NCAR/amwg_dev/tree/f.e30_cam6_4_127.FHISTC_LTso.ne30.dust_DGLC.001

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Sandbox:

• Locally (if still available):
  /glade/work/hannay/cesm_tags/cam6_4_127

• On github:
  https://github.com/ESCOMP/CAM/tree/cam6_4_127

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Diagnostics:

• ADF diags (if available)
  https://webext.cgd.ucar.edu/FLTHIST/f.e30_cam6_4_127.FHISTC_LTso.ne30.dust_DGLC.001/atm/

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Output:

• Raw output on derecho (if still available)
  /glade/derecho/scratch/hannay/archive/f.e30_cam6_4_127.FHISTC_LTso.ne30.dust_DGLC.001/
• CAM Climos: /glade/campaign/cgd/amp/amwg/climo/f.e30_cam6_4_127.FHISTC_LTso.ne30.dust_DGLC.001

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Contacts:
@cecilehannay @adamrher @dmleung

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Extra details:

[adamrher]

@cecilehannay can you run the ADF diags on this one compared to the CNTL #761 ?

[adamrher]

@dmleung I did an analysis of the TOA budget for this run here: https://docs.google.com/presentation/d/1ZoDdhePRLnItWOBJ0ScPbyxpUvL40Eo8wmg9jXviG9w/edit?usp=sharing.

It indicates that the dust changes have very little impact on the radiative fluxes. There is a large 1 W/m2 increase in absorbed clear-sky SW, but that is primarily due to the reduced sea salt emissions. I believe the trivial impact of the new dust on radiative fluxes was intended (changed dust optical properties to support the same AOD, but with a smaller burden). However, you have since revised dust_emis_fact = 3.4 -> 4.0. Is that still your latest recommendation? Separately, have you made any science changes as a result of the code review? We should do another run if any thing has changed since we started this run.

[cecilehannay]

ADF:
https://webext.cgd.ucar.edu/FLTHIST/f.e30_cam6_4_127.FHISTC_LTso.ne30.dust_DGLC.001/atm/

[dmleung]

Hi @adamrher, it looks good that including the dust changes didn't really purturb the aerosol radiative effect. Yes, this is expected as you said, because we increased dust extinction efficioncy and reduced dust emission/burden to maintain a similar level of dust AOD and radiative effect. It's good that your results verified that. I agree that from the plot it looks like that the major changes in the radiation comes from seasalt.
No, I didn't do any more science change in the PR ESCOMP/CAM#1426 and will unlikely do that further. I think the science change for the PR is pretty much done. I still need to edit the namelist_defaults in the PR.
Yes, I would like to further reduce global dust burden by ~ 10 % by enhancing dust_emis_fact a bit. Doing this, CAM7 Leung_2023 global mean dust AOD in the 2000s is reduced from ~0.03 to ~0.027. I hope that doesn't affect your aerosol forcings too much.