b.e30_alpha08b.B1850C_LTso.ne30_t232_wgx3.328

[gustavo-marques]

Purpose:

Same as 327, but with a longer time step for ocean thermodynamics and tracers. The goal is to assess the impact of this change on key climate metrics.

Because of CESM’s load-balancing strategy, this change will not improve overall performance in B compsets without BGC. The ocean component is already faster than the rest of the model and often waits idle. Taking a longer time step for ocean thermodynamics and tracers would just increase this idle time without speeding up the full system. Carefully reducing ocean resource usage (NTASKS_OCN) could reduce idle time and save compute resources.

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Description:
Same as 327 (#311) except:

• MOM_interfaces @ aa948d4fd

• MOM6 @ b15bc9780

• user_nl_mom

THERMO_SPANS_COUPLING = True 
DT_THERM = 7200
DT_TRACER_ADVECT = 7200

INPUTDIR = "INPUT"
GRID_FILE = "ocean_hgrid_250930.nc"
TOPO_FILE = "ocean_topo_tx2_3v3_260305.nc"
TOPO_EDITS_FILE = ""
TIDAL_ENERGY_FILE = "tidal_energy_tx2_3v3_conserve_260306.nc"
CHL_FILE = "seawifs-clim-1997-2010-tx2_3v3_260305.nc"
CHANNEL_LIST_FILE = "channels_tx2_3v3_260304.txt"
GEOTHERMAL_FILE = "geothermal_davies2013_tx2_3v3_260305.nc"
MLE%
CR_FILE = "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


THICKNESS_CONFIG = thickness_file
VELOCITY_CONFIG = file
TS_CONFIG = file

INIT_LAYERS_FROM_Z_FILE = False

THICKNESS_FILE = "/glade/derecho/scratch/gmarques/archive/g.e30_a08g.GW_JRA.TL319_t232_wgx3_hycom1_N75.2026.006/rest/0008-01-01-00000/g.e30_a08g.GW_JRA.TL319_t232_wgx3_hycom1_N75.2026.006.mom6.r.0008-01-01-00000.nc"

TS_FILE = "/glade/derecho/scratch/gmarques/archive/g.e30_a08g.GW_JRA.TL319_t232_wgx3_hycom1_N75.2026.006/rest/0008-01-01-00000/g.e30_a08g.GW_JRA.TL319_t232_wgx3_hycom1_N75.2026.006.mom6.r.0008-01-01-00000.nc"
VELOCITY_FILE = "/glade/derecho/scratch/gmarques/archive/g.e30_a08g.GW_JRA.TL319_t232_wgx3_hycom1_N75.2026.006/rest/0008-01-01-00000/g.e30_a08g.GW_JRA.TL319_t232_wgx3_hycom1_N75.2026.006.mom6.r.0008-01-01-00000.nc"

TEMP_IC_VAR = "Temp"
SALT_IC_VAR = "Salt"

• change runoff

./xmlchange ROF2OCN_ICE_RMAPNAME=/glade/u/home/igrooms/runoff_mapping/map_r05_to_tx2_3_nnsm_e100r100sh_e250r250nh_merged_modified_260317.nc
./xmlchange ROF2OCN_LIQ_RMAPNAME=/glade/work/gmarques/cesm/tx2_3/runoff_mapping/map_r05_to_tx2_3_nnsm_e100r100_260306.nc

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Case directory:

• Locally (if still available):
  /glade/campaign/cesm/cesmdata/cseg/runs/cesm2_0/b.e30_alpha08b.B1850C_LTso.ne30_t232_wgx3.328

• On github:
  https://github.com/NCAR/cesm_dev/tree/b.e30_alpha08b.B1850C_LTso.ne30_t232_wgx3.328

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Sandbox:

• Locally (if still available): /glade/work/hannay/cesm_tags/cesm3_0_alpha08b

• On github: https://github.com/ESCOMP/cesm/tree/cesm3_0_alpha08b

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Diagnostics:

• Diags (if available):
  https://webext.cgd.ucar.edu/BLT1850/b.e30_alpha08b.B1850C_LTso.ne30_t232_wgx3.328/

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Output:

• Raw output on derecho (if still available): /glade/derecho/scratch/gmarques/archive/b.e30_alpha08b.B1850C_LTso.ne30_t232_wgx3.328/
• CAM Climos: /glade/campaign/cgd/amp/amwg/climo/b.e30_alpha08b.B1850C_LTso.ne30_t232_wgx3.328

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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:

[cecilehannay]

CUPiD [327 vs 328] from Dylan
(https://webext.cgd.ucar.edu/BLT1850/b.e30_alpha08b.B1850C_LTso.ne30_t232_wgx3.327/cupid_327_v_328/infrastructure/index.html)

[wwieder]

The land diagnostics didn't seem to work from CUPID. Is it hard to redo these?

[cecilehannay]

I will ask Dylan.

[cecilehannay]

@wwieder: I think it is fixed now.

[wwieder]

Thanks, as mentioned today 328 gets pretty cold and snowy in the Arctic. A longer run would be helpful, but at this point my preference is for 327

[dabail10]

Sea ice diagnostics. 328 definitely has a larger area and volume in the SH. A bit higher in the Arctic.

https://webext.cgd.ucar.edu/BLT1850/b.e30_alpha08b.B1850C_LTso.ne30_t232_wgx3.327/ice/html/infrastructure/index.html

[cecilehannay]

ADF for 328 vs 327: https://webext.cgd.ucar.edu/BLT1850/b.e30_alpha08b.B1850C_LTso.ne30_t232_wgx3.328/atm/