Component Tag:
cism-release-cesm2.1.2_04
HTML Created:
2024-09-20
Variable Namelist Group Category Entry Type Valid Values Possible Default Values Description and out-of-the-box Default
cism_debug cism_params cism logical ['.true.', '.false.'] .false.
Determines whether extra diagnostics are printed in the cism log file
Default: false
cisminputfile derived cism char*256 ['any char'] is glc/cism/gland20.input_c150415.nc for: {'glc_grid': 'gland20', 'cism_phys': 'cism1'}
is glc/cism/IceSheetData_UMontana/PresentDayGreenland/Greenland_5km_v1.1_SacksRev_c160720.nc for: {'glc_grid': 'gland5UM', 'cism_phys': 'cism1'}
is glc/cism/gland20.input_c150415.nc for: {'glc_grid': 'gland20', 'cism_phys': 'cism2'}
is glc/cism/Greenland/glissade/init/greenland_4km_epsg3413_c171126.nc for: {'glc_grid': 'gland4', 'cism_phys': 'cism2'}
Input file
Default: For startup runs or hybrid runs with CISM_OBSERVED_IC=TRUE, a resolution-dependent
         initial conditions file (e.g., gland20.input_c150415.nc).
         For branch/hybrid runs with CISM_OBSERVED_IC=FALSE, a restart file name
         built based on RUN_REFCASE and RUN_REFDATE.
ice_flux_routing cism_params cism char*64 ['ocn', 'ice'] ocn
Code describing how the solid ice runoff flux (i.e., calving) should
be routed.
ocn: all solid ice goes to the ocean component
ice: all solid ice goes to the sea ice component
Default: ocn
paramfile cism_params cism char*100 ['any char']
Name of top-level configuration file for CISM
(Determined by scripts -- cannot be set by user)
test_coupling cism_params cism logical ['.true.', '.false.'] .false.
If this is set to true, it sets the mass balance timestep to 1 day.
This means the ice dynamics is called after one day of climate simulation.
THIS IS ONLY FOR TESTING OF COUPLING PROCEDURES, NOT TO BE USED FOR SCIENCE.
zero_gcm_fluxes cism_params cism logical ['.true.', '.false.'] is .false. for: {'glc_two_way_coupling': 'TRUE', 'cism_evolve': 'TRUE'}
is .true. for: {'glc_two_way_coupling': 'FALSE', 'cism_evolve': 'TRUE'}
is .true. for: {'glc_two_way_coupling': 'TRUE', 'cism_evolve': 'FALSE'}
is .true. for: {'glc_two_way_coupling': 'FALSE', 'cism_evolve': 'FALSE'}
If true, zero out all fluxes sent to the GCM
Default: Depends on GLC_TWO_WAY_COUPLING xml variable
evolve_ice cism_config_climate cism_config_climate integer ['0', '1'] is 1 for: {'cism_evolve': 'TRUE'}
is 0 for: {'cism_evolve': 'FALSE'}
0: Do not let the ice sheet evolve (hold ice state fixed at initial condition)
1: Let the ice sheet evolve
Default: 1
ice_tstep_multiply cism_config_climate cism_config_climate integer ['any integer']
Ice time-step multiplier: allows asynchronous climate-ice coupling
Default: (use hard-coded default- currently 1)
dew cism_config_grid cism_config_grid real ['any real'] is 20000. for: {'glc_grid': 'gland20'}
is 5000. for: {'glc_grid': 'gland5UM'}
is 4000. for: {'glc_grid': 'gland4'}
Node spacing in x-direction (m)
Default: resolution-dependent
dns cism_config_grid cism_config_grid real ['any real'] is 20000. for: {'glc_grid': 'gland20'}
is 5000. for: {'glc_grid': 'gland5UM'}
is 4000. for: {'glc_grid': 'gland4'}
Node spacing in y-direction (m)
Default: resolution-dependent
ewn cism_config_grid cism_config_grid integer ['any integer'] is 76 for: {'glc_grid': 'gland20'}
is 301 for: {'glc_grid': 'gland5UM'}
is 416 for: {'glc_grid': 'gland4'}
Number of nodes in x-direction
Default: resolution-dependent
global_bc cism_config_grid cism_config_grid integer ['0', '1', '2'] is 0 for: {'cism_phys': 'cism1'}
is 1 for: {'cism_phys': 'cism2'}
Global boundary conditions
0: Doubly periodic
1: Free outflow; scalars in global halo set to zero
2: No penetration; outflow set to zero at global boundaries (only supported for Glissade dycore)
Default: 0 for cism1, 1 for cism2
nsn cism_config_grid cism_config_grid integer ['any integer'] is 141 for: {'glc_grid': 'gland20'}
is 561 for: {'glc_grid': 'gland5UM'}
is 704 for: {'glc_grid': 'gland4'}
Number of nodes in y-direction
Default: resolution-dependent
upn cism_config_grid cism_config_grid integer ['any integer'] 11
Number of nodes in z-direction
Default: 11
con cism_config_gthf cism_config_gthf real ['any real']
thermal conductivity of lithosphere (W m-1 K-1)
Only relevant if gthf = 2
Default: (use hard-coded default - currently 3.3)
nlayer cism_config_gthf cism_config_gthf integer ['any integer']
Number of vertical layers
Only relevant if gthf = 2
Default: (use hard-coded default - currently 20)
num_dim cism_config_gthf cism_config_gthf integer ['1', '3']
1: 1D calculations
3: 3D calculations
Only relevant if gthf = 2
Default: (use hard-coded default - currently 1)
numt cism_config_gthf cism_config_gthf integer ['any integer']
Number of time steps for spinning up GTHF calculations
Only relevant if gthf = 2
Default: (use hard-coded default - currently 0)
rho cism_config_gthf cism_config_gthf real ['any real']
Density of lithosphere (kg m-3)
Only relevant if gthf = 2
Default: (use hard-coded default - currently 3300.)
rock_base cism_config_gthf cism_config_gthf real ['any real']
Depth below sea-level at which geothermal heat gradient is applied (m)
Only relevant if gthf = 2
Default: (use hard-coded default - currently -5000.)
shc cism_config_gthf cism_config_gthf real ['any real']
Specific heat capacity of lithosphere (J kg-1 K-1)
Only relevant if gthf = 2
Default: (use hard-coded default - currently 1000.)
surft cism_config_gthf cism_config_gthf real ['any real']
Initial surface temperature (degrees C)
Only relevant if gthf = 2
Default: (use hard-coded default - currently 2.)
glissade_maxiter cism_config_ho_options cism_config_ho_options integer ['any integer'] 50
Maximum number of nonlinear iterations to be used by the Glissade velocity solver
Default: 50
which_ho_approx cism_config_ho_options cism_config_ho_options integer ['-1', '0', '1', '2', '3', '4'] 4
Flag that indicates which Stokes approximation to use with the Glissade dycore.
Not valid for other dycores.
-1: Shallow-ice approximation, Glide-type calculation (uses glissade_velo_sia)
0: Shallow-ice approximation, vertical-shear stresses only (uses glissade_velo_higher)
1: Shallow-shelf approximation, horizontal-plane stresses only (uses glissade_velo_higher)
2: Blatter-Pattyn approximation with both vertical-shear and horizontal-plane stresses (uses glissade_velo_higher)
3: Vertically integrated 'L1L2' approximation with vertical-shear and horizontal-plane stresses (uses glissade_velo_higher)
4: Depth-integrated viscosity approximation based on Goldberg (2011) (uses glissade_velo_higher)
Default: 4
which_ho_assemble_beta cism_config_ho_options cism_config_ho_options integer ['0', '1'] 1
Flag that describes how beta terms are assembled in the Glissade finite-element calculation
0: Standard finite-element calculation (which effectively smooths beta)
1: Apply local value of beta at each vertex
Default: 1
which_ho_assemble_bfric cism_config_ho_options cism_config_ho_options integer ['0', '1'] 1
Flag that describes how the basal friction heat flux is computed in the Glissade finite-element calculation
Not valid for other dycores
0: Standard finite-element calculation summing over quadrature points
1: Apply local value of beta*(u^2 + v^2) at each vertex
Default: 1
which_ho_assemble_taud cism_config_ho_options cism_config_ho_options integer ['0', '1'] 1
Flag that describes how driving-stress terms are assembled in the Glissade finite-element calculation
Not valid for other dycores
0: Standard finite-element calculation (which effectively smooths the driving stress)
1: Apply local value of driving stress at each vertex
Default: 1
which_ho_babc cism_config_ho_options cism_config_ho_options integer ['0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '10', '11', '12', '13', '14'] 3
Basal boundary condition for higher order dynamical core
0: spatially uniform value (low value of 10 Pa yr-1 by default)
1: large value for frozen bed, lower value for bed at pressure melting point
2: treat beta value as a till yield stress (in Pa) using Picard iteration 
3: pseudo-plastic basal sliding law; can model linear, power-law or plastic behavior
4: very large value for beta to enforce no slip everywhere 
5: beta field passed in from .nc input file as part of standard i/o
6: no slip everywhere (using Dirichlet BC rather than large beta)
7: treat beta value as till yield stress (in Pa) using Newton-type iteration (in development)
8: beta field as prescribed for ISMIP-HOM test C (serial only)
9: power law
10: Coulomb friction law using effective pressure, with flwa from lowest ice layer
11: Coulomb friction law using effective pressure, with constant basal flwa
12: basal stress is the minimum of Coulomb and power-law values, as in Tsai et al. (2015)
13: power law based on effective pressure
14: simple hard-coded pattern (useful for debugging)
Default: 3
which_ho_bwat cism_config_ho_options cism_config_ho_options integer ['0', '1', '2'] 2
Basal water depth
0: Set to zero everywhere
1: Set to constant everywhere, to force T = Tpmp.
2: Local basal till model with constant drainage
Default: 2
which_ho_calving_front cism_config_ho_options cism_config_ho_options integer ['0', '1'] 0
Flag that indicates whether to use a subgrid calving front parameterization
0: No subgrid calving front parameterization
1: Use subgrid calving front parameterization
Default: 0
which_ho_disp cism_config_ho_options cism_config_ho_options integer ['-1', '0', '1'] 1
Method for computing the dissipation during the temperature calculation
-1: no dissipation
0: 0-order SIA approx.
1: 1st order solution (e.g., Blatter-Pattyn)
Default: 1
which_ho_effecpress cism_config_ho_options cism_config_ho_options integer ['0', '1', '2', '3', '4'] 4
Flag that describes effective pressure calculation for higher order dynamical core
0: N = overburden pressure, rhoi*grav*thck
1: N is reduced where the bed is at or near the pressure melting point
2: N is reduced where there is melting at the bed
3: N is reduced due to the connection of subglacial water to the ocean
4: N is reduced where basal water is present
Default: 4
which_ho_efvs cism_config_ho_options cism_config_ho_options integer ['0', '1', '2'] 2
How effective viscosity is computed for higher-order dynamical core
0: constant value
1: multiple of flow factor
2: compute from effective strain rate
Default: 2
which_ho_gradient cism_config_ho_options cism_config_ho_options integer ['0', '1', '2'] 0
Which gradient operator to use in the Glissade dycore.
Not valid in other dycores.
NOTE: Upstream may be better for ice evolution because it damps checkerboard noise.
0: Centered gradient
1: First-order accurate upstream gradient
2: Second-order accurate upstream gradient
Default: 0
which_ho_gradient_margin cism_config_ho_options cism_config_ho_options integer ['0', '1', '2'] 1
How to compute the gradient at the ice margin in the Glissade dycore.
Not valid for other dycores.
Note: Gradients are always computed at edges with ice on both sides.
The methods differ in whether gradients are computed when an ice-covered cell
lies above an ice-free cell (land or ocean).
0: Compute edge gradient when either cell is ice-covered
1: Compute edge gradient for ice-covered cell above ice-free land (not ocean)
2: Compute edge gradient only when both cells have ice
Default: 1
which_ho_ground cism_config_ho_options cism_config_ho_options integer ['0', '2'] 0
Flag that indicates how the grounded ice fraction is computed in the Glissade dycore
Not valid for other dycores
0: fground = 0 in floating cells (based on flotation condition), else fground = 1 
1: [NOT SUPPORTED] fground between 0 and 1 (inclusive), based on a grounding line parameterization
2: fground = 1 in all cells
Default: 0
which_ho_ground_bmlt cism_config_ho_options cism_config_ho_options integer ['0', '1'] 0
Flag that indicates how to compute bmlt_float in partly grounded cells
0: Apply bmlt_float in all floating cells, including partly grounded cells
1: Do not apply bmlt_float in partly grounded cells
Default: 0
which_ho_nonlinear cism_config_ho_options cism_config_ho_options integer ['0', '1'] is 1 for: {'dycore': '1'}
is 0 for: {'dycore': '2'}
Method for solving the nonlinear iteration when solving the first-order momentum balance
0: use the standard Picard iteration
1: use Jacobian Free Newton Krylov (JFNK) method [GLAM only]
Default: 1 for dycore = 1, 0 for dycore = 2
which_ho_precond cism_config_ho_options cism_config_ho_options integer ['0', '1', '2'] 1
Flag that indicates which Stokes preconditioner to use in the Glissade dycore.
Not valid for other dycores.
0: No preconditioner
1: Diagonal preconditioner
2: Physics-based shallow-ice preconditioner
Default: 1
which_ho_resid cism_config_ho_options cism_config_ho_options integer ['0', '1', '2', '3', '4'] 4
Method for computing residual in Payne/Price dynamical core
0: maxval
1: maxval ignoring basal velocity
2: mean value
3: L2 norm of system residual, Ax-b=resid
4: L2 norm of system residual relative to rhs, |Ax-b|/|b|
Default: 4
which_ho_sparse cism_config_ho_options cism_config_ho_options integer ['-1', '0', '1', '2', '3', '4'] is 3 for: {'dycore': '2'}
is 1 for: {'dycore': '1', 'cism_use_trilinos': 'FALSE'}
is 4 for: {'dycore': '1', 'cism_use_trilinos': 'TRUE'}
Method for solving the sparse linear system that arises from the higher-order solver
-1: SLAP (serial) Preconditioned conjugate gradient, incomplete Cholesky preconditioner
0: SLAP (serial) Biconjugate gradient, incomplete LU preconditioner
1: SLAP (serial) GMRES, incomplete LU preconditioner
2: Native PCG, parallel-enabled, standard solver
3: Native PCG, parallel-enabled, Chronopoulos-Gear solver
4: standalone interface to Trilinos
The use of trilinos is NOT SUPPORTED in CESM runs.
Default: 3 if dycore = 2, 1 if dycore = 1 and cism_use_trilinos = FALSE
which_ho_thermal_timestep cism_config_ho_options cism_config_ho_options integer ['0', '1', '2'] 2
0: vertical thermal solve before transport solve
1: vertical thermal solve after transport solve
2: vertical thermal solve split; both before and after transport solve
Default: 2
asthenosphere cism_config_isostasy cism_config_isostasy integer ['0', '1']
0: fluid mantle, isostatic adjustment happens instantaneously
1: relaxing mantle, mantle is approximated by a half-space
Only relevant if isostasy = 1
Default: (use hard-coded default - currently 1)
flexural_rigidity cism_config_isostasy cism_config_isostasy real ['any real']
Flexural rigidity of the lithosphere
Only relevant if 'lithosphere' is set to 1
Default: (use hard-coded default - currently 0.24e25)
lithosphere cism_config_isostasy cism_config_isostasy integer ['0', '1']
0: local lithosphere, equilibrium bedrock depression is found using Archimedes' principle
1: elastic lithosphere, flexural rigidity is taken into account
Only relevant if isostasy = 1
Default: (use hard-coded default - currently 1)
lithosphere_period cism_config_isostasy cism_config_isostasy real ['any real']
Lithosphere update period (years)
Only relevant if isostasy = 1
Default: (use hard-coded default - currently 100.)
relaxed_tau cism_config_isostasy cism_config_isostasy real ['any real']
Characteristic time constant of relaxing mantle (years)
Only relevant if isostasy = 1
Default: (use hard-coded default - currently 4000.) 
whichrelaxed cism_config_isostasy cism_config_isostasy integer ['0', '1', '2']
0: relaxed topography is read from a separate variable
1: first time slice of input topography is assumed to be relaxed
2: first time slice of input topography is assumed to be in isostatic equilibrium with ice thickness
Default: (use hard-coded default - currently 0)
basal_mass_balance cism_config_options cism_config_options integer ['0', '1'] 1
0: not in continuity equation
1: in continuity equation
Default: 1
basal_water cism_config_options cism_config_options integer ['0', '1', '2', '3']
Determines the treatment of basal water
Only valid for Glide dycore (cism1)
0: Set to zero everywhere
1: Calculated from local water balance
2: Compute the basal water flux, then find depth via calculation
3: Set to constant everywhere (10m), to force T = Tpmp
Default: (use hard-coded default - currently 0)
bmlt_float cism_config_options cism_config_options integer ['0', '1', '2', '3', '4'] 0
Basal melt rate for floating ice
0: Basal melt rate = 0 for floating ice
1: Depth-dependent basal melt rate for floating ice as prescribed for MISMIP+
2: Basal melt rate = constant for floating ice (with option to selectively mask out melting)
3: Depth-dependent basal melt rate for floating ice
4: External basal melt rate field (from input file or coupler)
5: [NOT SUPPORTED] Basal melt rate for floating ice from MISOMIP ocean forcing with plume model
Default: 0
calving_domain cism_config_options cism_config_options integer ['0', '1'] 1
0: Calve only at ocean edge
1: Calve wherever the calving criterion is met
Default: 1
calving_init cism_config_options cism_config_options integer ['0', '1'] 1
0: Do not calve at initialization
1: Calve at initialization
Default: 1
cull_calving_front cism_config_options cism_config_options logical ['.true.', '.false.']
Expert setting.
If true, then cull calving_front cells at initialization.
This can make the run more stable by removing long, thin peninsulas.
If this is set, then also need to set ncull_calving_front.
Default: (use hard-coded default - currently .false.)
diag_minthck cism_config_options cism_config_options integer ['0', '1']
How to determine minimum thickness for diagnostic
0: global diagnostics include all cell with H > 0
1: global diagnostics include all cells with H > thklim
This change only affects log files, not output .nc files
Default: (use hard-coded default - currently 1)
dm_dt_diag cism_config_options cism_config_options integer ['0', '1'] 1
Switch units from kg/s to Gt/yr in the log file
0: use kg/s unit in log file
1: use Gt/yr unit in log file
This change only affects log files, not output .nc files
Default: 1
dycore cism_config_options cism_config_options integer ['0', '2'] is 0 for: {'cism_phys': 'cism1'}
is 2 for: {'cism_phys': 'cism2'}
Which dycore to use
0: Glide dycore (SIA, serial only)
1: NOT SUPPORTED: glam dycore (HO, FDM, serial or parallel)
   Note that this option is not allowed within CESM, because it is buggy
2: Glissade dycore (HO, FEM, serial or parallel)
Default: 0 for cism1, 2 for cism2
evolution cism_config_options cism_config_options integer ['0', '2', '3', '4', '5'] is 0 for: {'cism_phys': 'cism1'}
is 3 for: {'cism_phys': 'cism2'}
0: pseudo-diffusion
1: ADI scheme [CANNOT BE USED: RESTARTS ARE NOT EXACT]
2: diffusion
3: remap thickness
4: 1st order upwind
5: no thickness evolution
Options 0, 1 and 2 are for Glide dycore only
Options 3, 4 and 5 are for Glissade dycore only
Default: 0 for cism1, 3 for cism2
flow_law cism_config_options cism_config_options integer ['0', '1', '2', '3'] 2
0: Constant value, taken from default_flwa
1: Uniform value equal to the Paterson-Budd value at -10 deg C
2: Paterson-Budd temperature-dependent relationship
3: Read flwa/flwastag from file
Default: 2
gthf cism_config_options cism_config_options integer ['0', '1', '2'] is 0 for: {'cism_phys': 'cism1'}
is 1 for: {'cism_phys': 'cism2'}
0: prescribed uniform geothermal heat flux
1: read 2D geothermal flux field from input file, if present
   (if absent, fall back to prescribed uniform geothermal heat flux)
2: calculate geothermal flux using 3d diffusion
Default: 0 for cism1, 1 for cism2
isostasy cism_config_options cism_config_options integer ['0', '1'] 0
0: no isostasy
1: compute isostasy
Default: 0
limit_marine_cliffs cism_config_options cism_config_options logical ['.true.', '.false.'] .true.
If true, then thin marine-based cliffs based on a thickness threshold
Default: .true.
marine_margin cism_config_options cism_config_options integer ['0', '1', '2', '3', '4', '5', '6', '7', '8', '9'] 1
Calving
0: No calving
1: Set thickness to zero if floating
2: Lose a fraction of floating ice at marine margin
3: Set thickness to zero if relaxed bedrock is more than a certain water depth (marine_limit)
4: Set thickness to zero if present bedrock topography lies below a certain water depth (marine_limit)
5: Set thickness to zero based on grid location (field 'calving_mask')
6: Set thickness to zero if ice at marine margin is thinner than a certain value (calving_minthck)
7: Set thickness to zero based on stress (eigencalving) criterion
8: [NOT SUPPORTED] Calve ice that is sufficiently damaged
9: [NOT SUPPORTED] Huybrechts grounding line scheme for Greenland initialization
Default: 1
periodic_ew cism_config_options cism_config_options integer ['0', '1']
0: no periodic EW boundary conditions
1: periodic EW boundary conditions
(This is a Glimmer serial option. The parallel code enforces periodic
EW and NS boundary conditions by default.)
Default: (use hard-coded default - currently 0)
remove_icebergs cism_config_options cism_config_options logical ['.true.', '.false.'] .true.
If true, then identify and remove icebergs after calving.
These are connected regions with zero basal traction and no connection to grounded ice.
Safer to make it true (and this is needed for stability when allowing floating ice
with more advanced calving options), but not necessary for all applications.
Default: .true.
restart cism_config_options cism_config_options integer ['0', '1']
Restart the model if set to 1. 
This allows for exact restarts from previous initial conditions
Default: 0 for startup or hybrid with CISM_OBSERVED_IC=TRUE, 1 for hybrid/branch with CISM_OBSERVED_IC=FALSE
sigma cism_config_options cism_config_options integer ['0', '2', '3', '4'] 0
How to determine sigma values
0: compute standard Glimmer sigma coordinates
1: sigma coordinates are given in external file [NOT ALLOWED WHEN RUNNING CISM IN CESM]
2: read sigma coordinates from config file (from sigma_levels)
3: evenly spaced levels, as required for glam dycore
4: compute Pattyn sigma coordinates
Default: 0
slip_coeff cism_config_options cism_config_options integer ['0', '1', '2', '3', '4', '5'] 0
Basal traction parameter
Glide or Glissade local SIA (which_ho_approx = -1) only.
0: no basal sliding
1: constant basal traction coefficient
2: constant coefficient where basal water is present, else no sliding
3: constant coefficient where the basal temperature is at the pressure melting point, else no sliding
4: coefficient is proportional to basal melt rate
5: coefficient is a linear function of basal water depth
Default: 0
temp_init cism_config_options cism_config_options integer ['0', '1', '2', '3', '4'] is 2 for: {'cism_phys': 'cism1'}
is 3 for: {'cism_phys': 'cism2'}
Temperature initialization method
0: Initialize temperature to 0 C
1: Initialize temperature to surface air temperature
2: Initialize temperature with a linear profile in each column
3: Initialize temperature with an advective-diffusive balance in each column
4: Initialize temperature from external file
Default: 3 for cism2; 2 for cism1
temperature cism_config_options cism_config_options integer ['0', '1', '2', '3'] 1
Determines the temperature solution method
0: isothermal: set column to surface air temperature
1: prognostic temperature solution
2: do NOTHING: hold temperatures steady at initial value
3: prognostic enthalpy solution
Default: 1
vertical_integration cism_config_options cism_config_options integer ['0', '1'] 0
Method of integration used to obtain vertical velocity
0: standard vertical integration
1: vertical integration constrained to obey an upper kinematic boundary condition
Default: 0
basal_tract_const cism_config_parameters cism_config_parameters real ['any real'] 1.e-4
(m yr-1 Pa-1)
Relevant only when slip_coeff is relevant (Glide or Glissade local SIA)
Default: 1.e-4
basal_tract_max cism_config_parameters cism_config_parameters real ['any real']
(m yr-1 Pa-1)
(Only used for slip_coeff = BTRC_LINEAR_BMLT)
Default: (use hard-coded default - currently 0.)
basal_tract_slope cism_config_parameters cism_config_parameters real ['any real']
(Pa-1)
(Only used for slip_coeff = BTRC_LINEAR_BMLT)
Default: (use hard-coded default - currently 0.)
basal_tract_tanh cism_config_parameters cism_config_parameters real(5) ['any real(5)']
5-element list of values
(Only used for slip_coeff = BTRC_TANH_BWAT)
Default: (use hard-coded default - currently 0.2d0, 0.5d0, 0.0d0 ,1.0d-2, 1.0d0)
beta_grounded_min cism_config_parameters cism_config_parameters real ['any real'] 100.
Minimum value of beta for grounded ice (Pa yr m-1)
(Applies only to Glissade higher-order dycore)
Default: 100.
bmlt_float_depth_frzmax cism_config_parameters cism_config_parameters real ['any real'] 0.
Parameter for bmlt_float=3 (depth-dependent basal melt rate for floating ice):
Max freezing rate near surface (m/yr).
(Ignored for other bmlt_float options.)
Default: 0.
bmlt_float_depth_meltmax cism_config_parameters cism_config_parameters real ['any real'] 10.
Parameter for bmlt_float=3 (depth-dependent basal melt rate for floating ice):
Max melt rate at depth (m/yr).
(Ignored for other bmlt_float options.)
Default: 10.
bmlt_float_depth_zfrzmax cism_config_parameters cism_config_parameters real ['any real'] -100.
Parameter for bmlt_float=3 (depth-dependent basal melt rate for floating ice):
Depth (m) above which bmlt_float = -frzmax.
(Ignored for other bmlt_float options.)
Default: -100.
bmlt_float_depth_zmelt0 cism_config_parameters cism_config_parameters real ['any real'] -200.
Parameter for bmlt_float=3 (depth-dependent basal melt rate for floating ice):
Depth (m) where bmlt_float = 0.
(Ignored for other bmlt_float options.)
Default: -200.
bmlt_float_depth_zmeltmax cism_config_parameters cism_config_parameters real ['any real'] -500.
Parameter for bmlt_float=3 (depth-dependent basal melt rate for floating ice):
Depth (m) below which bmlt_float = meltmax.
(Ignored for other bmlt_float options.)
Default: -500.
bmlt_float_h0 cism_config_parameters cism_config_parameters real ['any real'] 75.
Scale for sub-shelf cavity thickness (m)
Default: 75.
bwat_till_max cism_config_parameters cism_config_parameters real ['any real'] 2.0
Parameter for local till model: Maximum water depth in till (m)
Relevant only for which_ho_bwat = 2
Default: 2.0
c_drainage cism_config_parameters cism_config_parameters real ['any real'] 1.e-3
Parameter for local till model: Uniform drainage rate (m/yr)
Relevant only for which_ho_bwat = 2
Default: 1.e-3
calving_fraction cism_config_parameters cism_config_parameters real ['any real']
Fraction of ice lost to calving (marine_margin = 2 only)
Default: (use hard-coded default - currently 0.2)
calving_minthck cism_config_parameters cism_config_parameters real ['any real'] 100.
Minimum thickness of floating ice at marine edge before it calves (m)
Default: 100.
calving_timescale cism_config_parameters cism_config_parameters real ['any real'] 0.
Timescale for calving (yr) (Glissade only)
calving_thck = thck*max(dt/calving_timescale,1)
If calving_timescale = 0, then the full column calves at once
Default: 0.
cliff_timescale cism_config_parameters cism_config_parameters real ['any real'] 0.
Time scale (yr) for limiting marine cliffs (Glissade only)
Default: 0.
damage_constant cism_config_parameters cism_config_parameters real ['any real']
Damage rate (1/yr) per unit stress (Pa)
[NOT SUPPORTED]
Default: (use hard-coded default - currently 1.e-7)
damage_threshold cism_config_parameters cism_config_parameters real ['any real']
Damage threshold for calving
[NOT SUPPORTED]
Default: (use hard-coded default - currently 0.75)
default_flwa cism_config_parameters cism_config_parameters real ['any real']
Glen's A to use in isothermal case, i.e, when temperature = 0
Default: (use hard-coded default - currently 1.e-16)
effecpress_bmlt_threshold cism_config_parameters cism_config_parameters real ['any real']
Basal melting range over which N ramps from a small value to full overburden (m/yr)
Relevant only for which_ho_effecpress = 2
Default: (use hard-coded default - currently 1.0d-3)
effecpress_bpmp_threshold cism_config_parameters cism_config_parameters real ['any real']
Parameter for reducing the effective pressure where the bed is warm, saturated or connected to the ocean:
Temperature range over which N ramps from a small value to full overburden (deg C)
Only applies for which_ho_effecpress = 1.
Default: (use hard-coded default - currently 0.1)
effecpress_delta cism_config_parameters cism_config_parameters real ['any real'] 0.02
Parameter for reducing the effective pressure where the bed is warm, saturated or connected to the ocean:
Multiplier for effective pressure N where the bed is saturated and/or thawed (unitless)
Default: 0.02
eigen2_weight cism_config_parameters cism_config_parameters real ['any real']
Weight that can increase lateral calving rate (eigencalving_constant).
Used only with marine_margin = 7 and 8
Default: (use hard-coded default - currently 1.)
eigencalving_constant cism_config_parameters cism_config_parameters real ['any real']
Lateral calving rate (m/yr) per unit stress (Pa)
Used only with marine_margin = 7 and 8
Default: (use hard-coded default - currently 0.01)
flow_factor cism_config_parameters cism_config_parameters real ['any real'] is 3. for: {'cism_phys': 'cism1'}
is 1. for: {'cism_phys': 'cism2'}
Flow enhancement parameter for the Arrhenius relationship;
typically used in SIA model to speed up the ice.
Default: 3.0 for cism1, 1.0 for cism2
flow_factor_float cism_config_parameters cism_config_parameters real ['any real'] 1.
Flow enhancement parameter for floating ice.
Default is 1.0, but for marine simulations a smaller value
may be needed to match observed shelf speeds.
Default: 1.0
geothermal cism_config_parameters cism_config_parameters real ['any real'] -5.e-2
Constant geothermal heat flux (W m-2; sign convention is positive down)
(May be overwritten by a spatially-varying field in input file [bheatflx])
Default: -0.05
ho_beta_const cism_config_parameters cism_config_parameters real ['any real']
Only relevant for which_ho_babc = 0 
Spatially uniform beta for higher-order dycores (Pa yr m-1)
Default: (use hard-coded default - currently 1000.)
hydro_time cism_config_parameters cism_config_parameters real ['any real']
Time scale for basal water to drain (yr-1)
Only relevant for cism1 (Glide dycore)
(Not relevant for basal_water=2)
Default: (use hard-coded default - currently 1000.)
ice_limit cism_config_parameters cism_config_parameters real ['any real'] is 100. for: {'cism_phys': 'cism1'}
is 1. for: {'cism_phys': 'cism2'}
Thickness below which ice dynamics is ignored (m)
Below this limit, ice is only accumulated
Default: 100 for cism1, 1 for cism2
log_level cism_config_parameters cism_config_parameters integer ['0', '1', '2', '3', '4', '5', '6'] 6
Set to a value between 0 (no messages) and 6 (all messages)
Default: 6
marine_limit cism_config_parameters cism_config_parameters real ['any real']
All ice is assumed lost once water depths reach this value (for marine_margin=3 or 4) (m)
Note that water depth is negative
Default: (use hard-coded default - currently -200.)
max_slope cism_config_parameters cism_config_parameters real ['any real'] 0.1
Maximum surface slope used in the Glissade driving-stress calculation (unitless)
Not valid for other dycores
Default: 0.1
ncull_calving_front cism_config_parameters cism_config_parameters integer ['any integer']
Number of times to cull calving_front cells at initialization
Set to a larger value to remove thicker peninsulas
To use this, also set cull_calving_front to .true.
Default: (use hard-coded default - currently 0)
periodic_offset_ew cism_config_parameters cism_config_parameters real ['any real']
Optional periodic offset for ismip-hom and similar tests
May be needed to ensure continuous ice geometry at the edges of the
global domain
Default: (use hard-coded default - currently 0.)
periodic_offset_ns cism_config_parameters cism_config_parameters real ['any real']
Optional periodic offset for ismip-hom and similar tests
May be needed to ensure continuous ice geometry at the edges of the
global domain
Default: (use hard-coded default - currently 0.)
pmp_offset cism_config_parameters cism_config_parameters real ['any real'] 5.
Offset of initial Tbed from pressure melting point temperature (deg C)
Default: 5.
pseudo_plastic_bedmax cism_config_parameters cism_config_parameters real ['any real'] 700.
Parameter for pseudo-plasting sliding law:
Bed elevation above which phi = phimax (m)
Default: 700.
pseudo_plastic_bedmin cism_config_parameters cism_config_parameters real ['any real'] -700.
Parameter for pseudo-plasting sliding law:
Bed elevation below which phi = phimin (m)
Default: -700.
pseudo_plastic_phimax cism_config_parameters cism_config_parameters real ['any real'] 40.
Parameter for pseudo-plasting sliding law:
max(phi) in pseudo-plastic law, for topg >= bedmin (degrees)
0 < phi < 90
Default: 40.
pseudo_plastic_phimin cism_config_parameters cism_config_parameters real ['any real'] 5.
Parameter for pseudo-plasting sliding law:
min(phi) in pseudo-plastic law, for topg <= bedmin (degrees)
0 < phi < 90
Default: 5.
pseudo_plastic_q cism_config_parameters cism_config_parameters real ['any real'] 0.5
Parameter for pseudo-plasting sliding law:
Exponent for pseudo-plastic law (unitless)
0 <= q <= 1
q = 1: linear sliding law
q = 0: plastic
Intermediate values: power law
Default: 0.5
pseudo_plastic_u0 cism_config_parameters cism_config_parameters real ['any real'] 100.
Parameter for pseudo-plasting sliding law:
Threshold velocity for pseudo-plastic law (m yr-1)
Default: 100.
taumax_cliff cism_config_parameters cism_config_parameters real ['any real'] 1.e6
Yield stress (Pa) for marine-based ice cliffs (Glissade only)
Default: 1.e6
thck_gradient_ramp cism_config_parameters cism_config_parameters real ['any real'] 50.
Thickness scale (in meters) over which gradients increase from zero to full value (HO only)
This parameter does not exist in CISM1 thus CISM2 only.
Default: 50.
sigma_levels cism_config_sigma cism_config_sigma real(20) ['any real(20)'] 0.00 0.15 0.30 0.45 0.60 0.75 0.83 0.90 0.95 0.98 1.00
List of sigma levels, in ascending order, separated by spaces
These run between 0.0 (at top surface) and 1.0 (at lower surface)
Only relevant if sigma = 2
Default: 0.00 0.15 0.30 0.45 0.60 0.75 0.83 0.90 0.95 0.98 1.00
adaptive_cfl_threshold cism_config_time cism_config_time real ['any real'] is 0.0 for: {'cism_phys': 'cism1'}
is 0.5 for: {'cism_phys': 'cism2'}
Adaptively subcycle the advection when advective CFL exceeds this value (Glissade only)
(Zero value means no adaptive subcycling.)
A nonzero value makes it possible for CISM to run with large velocities
that otherwise would violate the advective CFL limit. Results are
generally more accurate and stable, however, if the model is run with a
time step short enough to avoid subcycling.
Default: 0.5 for cism2
dt cism_config_time cism_config_time real ['any real'] is 0.1 for: {'glc_grid': 'gland20', 'cism_phys': 'cism1'}
is 0.05 for: {'glc_grid': 'gland5UM', 'cism_phys': 'cism1'}
is 0.5 for: {'glc_grid': 'gland20', 'cism_phys': 'cism2'}
is 0.1 for: {'glc_grid': 'gland4', 'cism_phys': 'cism2'}
Ice sheet timestep (years)
Must translate into an integer number of hours
Default: Depends on resolution and physics option
dt_diag cism_config_time cism_config_time real ['any real'] is 0.1 for: {'glc_grid': 'gland20', 'cism_phys': 'cism1'}
is 0.05 for: {'glc_grid': 'gland5UM', 'cism_phys': 'cism1'}
is 0.5 for: {'glc_grid': 'gland20', 'cism_phys': 'cism2'}
is 0.1 for: {'glc_grid': 'gland4', 'cism_phys': 'cism2'}
Diagnostic frequency (years)
Set to 0 for no diagnostic output; set to dt for diagnostic output every time step
Default: Same as dt
idiag cism_config_time cism_config_time integer ['any integer'] is 19 for: {'glc_grid': 'gland20'}
is 76 for: {'glc_grid': 'gland5UM'}
is 134 for: {'glc_grid': 'gland4'}
x coordinate of point for diagnostic output
Default: resolution-dependent
jdiag cism_config_time cism_config_time integer ['any integer'] is 57 for: {'glc_grid': 'gland20'}
is 228 for: {'glc_grid': 'gland5UM'}
is 280 for: {'glc_grid': 'gland4'}
y coordinate of point for diagnostic output
Default: resolution-dependent
ntem cism_config_time cism_config_time integer ['any integer']
Multiplier of ice sheet timestep, dt
(in theory, can be real-valued, but values less than 1 are not handled properly, so restricted to being an integer)
Default: (use hard-coded default: 1)
profile cism_config_time cism_config_time integer ['any integer']
Profile period (number of time steps between profiles)
Option for Glide dycore only
Default: 100
subcyc cism_config_time cism_config_time integer ['any integer']
Subcycling for Glissade
Default: 1
cesm_history_vars cism_history history char*1024 ['any char'] is 'smb artm thk usurf topg uvel vvel uflx vflx temp bmlt bwat' for: {'cism_phys': 'cism1', 'cism_evolve': 'TRUE'}
is 'smb artm thk usurf topg' for: {'cism_phys': 'cism1', 'cism_evolve': 'FALSE'}
is 'smb artm thk usurf topg uvel vvel temp bmlt bwat beta_internal floating_mask grounded_mask bpmp acab_applied bmlt_applied calving_rate iareaf iareag imass imass_above_flotation total_smb_flux total_bmb_flux total_calving_flux total_gl_flux' for: {'cism_phys': 'cism2', 'cism_evolve': 'TRUE'}
is 'smb artm thk usurf topg' for: {'cism_phys': 'cism2', 'cism_evolve': 'FALSE'}
Space-delimited list of variables output to history file
Default: Depends on physics and ice evolution options
history_frequency cism_history history integer ['any integer'] 1
History frequency
e.g., if history_option=nyears, then 1 = annual, 2 = every two years, etc.
Ignored for history_option = 'coupler'
Default: 1
history_option cism_history history char*64 ['nyears', 'coupler'] nyears
How history frequency is specified
nyears: Write history every N years
coupler: Get history frequency from coupler (HIST_OPTION/HIST_N xml variables)
         WARNING: SHOULD NOT BE USED IN PRODUCTION RUNS - frequency metadata not set properly
Default: nyears
decrease_frac glc_override_nml overrides real ['any real'] 0.0
Fractional decrease in glacier area, per day (should be positive).
(days_elapsed * decrease_frac) determines the elevation threshold below which ice_covered is set to 0.
When this factor reaches 1, all elevations below 3500 m are set to non-ice-covered.
Default: 0 (no decrease)
decrease_override_delay glc_override_nml overrides integer ['any integer'] 0
Time delay before beginning decrease_frac overrides (days).
Default: 0 (start overrides at beginning of run)
enable_frac_overrides glc_override_nml overrides logical ['.true.', '.false.'] .false.
Whether to enable overrides of the glc fraction sent to the coupler.
If this is false, the other settings in this namelist group are ignored.
ONLY MEANT FOR TESTING - SHOULD NOT BE USED FOR SCIENCE RUNS.
Default: .false.
increase_frac glc_override_nml overrides real ['any real'] 0.0
Fractional increase in glacier area, per day.
(days_elapsed * increase_frac) determines the elevation threshold above which ice_covered is set to 1.
When this factor reaches 1, all elevations >= 0 m are set to ice-covered.
Default: 0 (no increase)
increase_override_delay glc_override_nml overrides integer ['any integer'] 0
Time delay before beginning increase_frac overrides (days).
Default: 0 (start overrides at beginning of run)
rearrange_freq glc_override_nml overrides integer ['any integer'] 0
Frequency (days) at which we rearrange elevation classes.
Default: 0 (no flips ever)
rearrange_override_delay glc_override_nml overrides integer ['any integer'] 0
Time delay before beginning rearrange_freq overrides (days).
Default: 0 (start overrides at beginning of run)
allow_leapyear time_manager_nml time logical ['.true.', '.false.'] .true.
is .false. for: {'calendar': 'NO_LEAP'}
Whether leap years are enabled in the GLC time manager.
CAUTION: Leap years don't work correctly with GLC time steps longer than a few months.
Default: .false. for NO_LEAP calendar, .true. otherwise
date_separator time_manager_nml time char*1 ['any char'] -
Character to separate date values
Default: '-'
dt_count time_manager_nml time real ['any real']
Time step, in units given by dt_option
This generally should not be changed
Default: set based on NCPL_BASE_PERIOD and GLC_NCPL in env_run.xml,
so that there is one GLC time step per coupling period
dt_option time_manager_nml time char*80 ['steps_per_year', 'steps_per_day', 'seconds', 'hours']
GLC time-step units
This generally should not be changed
Valid values: steps_per_year, steps_per_day, seconds, hours
Default: set based on NCPL_BASE_PERIOD and GLC_NCPL in env_run.xml,
so that there is one GLC time step per coupling period
iday0 time_manager_nml time integer ['1', '2', '3', '4', '5', '6', '7', '8', '9', '10', '11', '12', '13', '14', '15', '16', '17', '18', '19', '20', '21', '22', '23', '24', '25', '26', '27', '28', '29', '30', '31']
Starting day number in month
Default: comes from RUN_STARTDATE or RUN_REFDATE
ihour0 time_manager_nml time integer ['0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '10', '11', '12', '13', '14', '15', '16', '17', '18', '19', '20', '21', '22', '23']
Starting hour of the day
Default: 0
iminute0 time_manager_nml time integer ['0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '10', '11', '12', '13', '14', '15', '16', '17', '18', '19', '20', '21', '22', '23', '24', '25', '26', '27', '28', '29', '30', '31', '32', '33', '34', '35', '36', '37', '38', '39', '40', '41', '42', '43', '44', '45', '46', '47', '48', '49', '50', '51', '52', '53', '54', '55', '56', '57', '58', '59']
Starting minute of the day
Default: 0
imonth0 time_manager_nml time integer ['1', '2', '3', '4', '5', '6', '7', '8', '9', '10', '11', '12']
Starting month number
Default: comes from RUN_STARTDATE or RUN_REFDATE
isecond0 time_manager_nml time integer ['0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '10', '11', '12', '13', '14', '15', '16', '17', '18', '19', '20', '21', '22', '23', '24', '25', '26', '27', '28', '29', '30', '31', '32', '33', '34', '35', '36', '37', '38', '39', '40', '41', '42', '43', '44', '45', '46', '47', '48', '49', '50', '51', '52', '53', '54', '55', '56', '57', '58', '59']
Starting second of the minute
Default: 0
iyear0 time_manager_nml time integer ['any integer']
Starting year number
Default: comes from RUN_STARTDATE or RUN_REFDATE
runid time_manager_nml time char*128 ['any char']
Simulation identifier (ie case name)
Default: case name set by create_newcase
stop_option time_manager_nml time char*80 ['never'] never
Stop option -- always let the coupler stop the model so use 'never'.
Default: 'never'
Variable Namelist Group Category Entry Type Valid Values Possible Default Values Description and out-of-the-box Default