b.e30_beta08_dev_ncar.B1850C_MTso.ne30_t232_wgx3.336

Start with the case directory and the user_nl_mom settings listed in the issue, then review the related issue 335 before changing anything. Run or inspect case b.e30_beta08_dev_ncar.B1850C_MTso.ne30_t232_wgx3.336 and use the linked diagnostics and output locations to determine whether the requested parameter effects were evaluated.

Purpose:
Purpose:
Check the effects of setting the defaut values in four MOM6 parameters

BBL_EFFIC = 0.01 instead of 0.2
! The efficiency with which the energy extracted by bottom drag drives BBL
! diffusion. This is only used if BOTTOMDRAGLAW is true.

This change will reduce the tracer diffusion near the bottom and will enhance the ouvwrflows. This only affect the Nordic Seas overflwos and has a minum effect on the Antarctic overflows.

NU_ZERO = 0.005 instead of 0.0025
! Leading coefficient in KPP shear mixing

This change will double the shear-driven mixing. It improves the Equatorial Undercurrent in G cases and we want to see if that's also the case in coupled runs.

RI_ZERO = 0.8 instead of 0.5
! Critical Richardson for KPP shear mixing, NOTE this the internal mixing and
! this is not for setting the boundary layer depth.

This changes the treshold for when the interior mixing is activated. It improves the Equatorial Undercurrent in G cases and we want to see if that's also the case in coupled runs.

MLE_DENSITY_DIFF = 0.03 fro 0.02
!Density difference used to detect the mixed-layer depth used for the
! mixed-layer eddy parameterization.

This is a very small difference and we do not expect significnat changes from it.

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Description:
Same as 335 + reverting some MOM6 parameters to the default values.

• user_nl_mom:

BBL_EFFIC = 0.01
NU_ZERO = 0.005
RI_ZERO = 0.8
MLE_DENSITY_DIFF = 0.03

INPUTDIR = "/glade/derecho/scratch/hannay/b.e30_alpha08o.B1850C_MTso.ne30_t232_wgx3.330/run/INPUT"
GRID_FILE = "[ocean_hgrid_250930.nc](http://ocean_hgrid_250930.nc/)"
TOPO_FILE = "[ocean_topo_tx2_3v3_260305.nc](http://ocean_topo_tx2_3v3_260305.nc/)"
TOPO_EDITS_FILE = ""
TIDAL_ENERGY_FILE = "[tidal_energy_tx2_3v3_conserve_260306.nc](http://tidal_energy_tx2_3v3_conserve_260306.nc/)"
CHL_FILE = "[seawifs-clim-1997-2010-tx2_3v3_260305.nc](http://seawifs-clim-1997-2010-tx2_3v3_260305.nc/)"
CHANNEL_LIST_FILE = "channels_tx2_3v3_260304.txt"
GEOTHERMAL_FILE = "[geothermal_davies2013_tx2_3v3_260305.nc](http://geothermal_davies2013_tx2_3v3_260305.nc/)"
MLE%
CR_FILE = "[mle_cr_labsea_mask_tx2_3v3_260306.nc](http://mle_cr_labsea_mask_tx2_3v3_260306.nc/)"
%MLE

MEKE_GEOMETRIC_ALPHA = 0.07
SMAGORINSKY_KH = False
MAXTRUNC = 1.0E6

! Leith+E Settings
TAPER_LEITHY = True
LEITH_BI_CONST = 85.0
LEITHY_CK = 1.0
LEITHY_DEPTH = 1000.0
LEITHY_WIDTH = 500.0

! Background KH
USE_KH_BG_2D = True
KH_BG_2D_FILENAME = "KH_BG_2D_tx2_3v3_260306.nc"
KH_BG_2D_VARNAME = "KH"

! Resolution scaling:
!! GM & Redi the same
!! Don't apply scaling to Laplacian viscosity, which is the 2D background
RESOLN_SCALED_KH = False
RESOLN_SCALED_KHTH = True  ! Already using, here for clarity
RESOLN_SCALED_KHTR = True  ! Already using, here for clarity
KH_RES_SCALE_COEF = 0.5    ! Tighter around the equator
KH_RES_FN_POWER = 6        ! Already using, here for clarity
VISC_RES_SCALE_COEF = 0.5  ! Used for KHTR
VISC_RES_FN_POWER = 6      ! Used for KHTR
INTERPOLATE_RES_FN = True  ! Only computes resolution fn once, then interpolates

KHTR_MIN = 50.

CORRECT_BBL_BOUNDS = True
CHANNEL_DRAG_MAX_BBL_THICK = 5.0

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Case directory:

• Locally (if still available):
  /glade/campaign/cesm/cesmdata/cseg/runs/cesm2_0/b.e30_beta08_dev_ncar.B1850C_MTso.ne30_t232_wgx3.336

• On github:
  https://github.com/NCAR/cesm_dev/tree/b.e30_beta08_dev_ncar.B1850C_MTso.ne30_t232_wgx3.336

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Sandbox:

• Locally (if still available): /glade/work/gmarques/cesm.sandboxes/cesm3_0_beta08_dev_ncar/

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Diagnostics:

• Diags (if available):
  https://webext.cgd.ucar.edu/BMT1850/b.e30_beta08_dev_ncar.B1850C_MTso.ne30_t232_wgx3.336/

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Output:

• Raw output on derecho (if still available): /glade/derecho/scratch/hannay/archive/b.e30_beta08_dev_ncar.B1850C_MTso.ne30_t232_wgx3.336/
• CAM Climos: /glade/campaign/cgd/amp/amwg/climo/b.e30_beta08_dev_ncar.B1850C_MTso.ne30_t232_wgx3.336

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Contacts:
@cecilehannay @dlawrenncar @adamrher @PeterHjortLauritzen @JulioTBacmeister @swrneale @slevis-lmwg @wwieder @olyson @gustavo-marques @iangrooms @fobryan3 @klindsay28 @dabail10 @duvivier @tilmes @mbramberger @gunterl

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Extra details: