5. Index of primary variables and parameters

This index defines many (but not all) of the symbols used frequently in the CICE model code. All quantities in the code are expressed in MKS units (temperatures may take either Celsius or Kelvin units). Deprecated parameters are listed at the end.

Namelist variables are partly included here, but they are fully documented in section Tables of Namelist Options.

Alphabetical Index

A
a11,a12	structure tensor components
a2D	history field accumulations, 2d
a3Dz	history field accumulations, 3D vertical
a3Db	history field accumulations, 3D bio grid
a3Dc	history field accumulations, 3D categories
a3Df	history field accumulations, 3D fsd
a4Di	history field accumulations, 4D categories, vertical ice
a4Db	history field accumulations, 4D categories, vertical bio grid
a4Ds	history field accumulations, 4D categories, vertical snow
a4Df	history field accumulations, 4D categories, fsd
a_min	minimum area concentration for computing velocity	0.001
a_rapid_mode	brine channel diameter
add_mpi_barriers	turns on MPI barriers for communication throttling
advection	type of advection algorithm used (‘remap’ or ‘upwind’)	remap
afsd(n)	floe size distribution (in category n)
ahmax	thickness above which ice albedo is constant	0.3m
aice_extmin	minimum value for ice extent diagnostic	0.15
aice_init	concentration of ice at beginning of timestep
aice0	fractional open water area
aice(n)	total concentration of ice in grid cell (in category n)
albedo_type	type of albedo parameterization (‘ccsm3’ or ‘constant’)
albcnt	counter for averaging albedo
albice	bare ice albedo
albicei	near infrared ice albedo for thicker ice
albicev	visible ice albedo for thicker ice
albocn	ocean albedo	0.06
albpnd	melt pond albedo
albsno	snow albedo
albsnowi	near infrared, cold snow albedo
albsnowv	visible, cold snow albedo
algalN	algal nitrogen concentration	mmol/m\(^3\)
alv(n)dr(f)	albedo: visible (near IR), direct (diffuse)
alv(n)dr(f)_ai	grid-box-mean value of alv(n)dr(f)
amm	ammonia/um concentration	mmol/m\(^3\)
ANGLE	for conversions between the POP grid and latitude-longitude grids	radians
ANGLET	ANGLE converted to T-cells	radians
aparticn	participation function
apeff_ai	grid-cell-mean effective pond fraction
apondn	area concentration of melt ponds
arlx1i	relaxation constant for dynamics (stress)
araftn	area fraction of rafted ice
aredistrn	redistribution function: fraction of new ridge area
ardgn	fractional area of ridged ice
aspect_rapid_mode	brine convection aspect ratio	1
astar	e-folding scale for participation function	0.05
atmiter_conv	convergence criteria for ustar	0.00
atm_data_dir	directory for atmospheric forcing data
atm_data_format	format of atmospheric forcing files
atm_data_type	type of atmospheric forcing
atmbndy	atmo boundary layer parameterization (‘similarity’, ‘constant’, or ‘mixed’)
avail_hist_fields	type for history field data
awtidf	weighting factor for near-ir, diffuse albedo	0.36218
awtidr	weighting factor for near-ir, direct albedo	0.00182
awtvdf	weighting factor for visible, diffuse albedo	0.63282
awtvdr	weighting factor for visible, direct albedo	0.00318
B
bfbflag	for bit-for-bit reproducible diagnostics, and reproducible outputs when using the VP solver
bgc_data_dir	data directory for bgc
bgc_data_type	source of silicate, nitrate data
bgc_flux_type	ice–ocean flux velocity
bgc_tracer_type	tracer_type for bgc tracers
bgrid	nondimensional vertical grid points for bio grid
bignum	a large number	\(10^{30}\)
block	data type for blocks
block_id	global block number
block_size_x(y)	number of cells along x(y) direction of block
blockGlobalID	global block IDs
blockLocalID	local block IDs
blockLocation	processor location of block
blocks_ice	local block IDs
bphi	porosity of ice layers on bio grid
brlx	relaxation constant for dynamics (momentum)
bTiz	temperature of ice layers on bio grid
C
c<n>	real(\(n\))
rotate_wind	if true, rotate wind/stress components to computational grid	T
calc_dragio	if true, calculate dragio from iceruf_ocn and thickness_ocn_layer1	F
calc_strair	if true, calculate wind stress	T
calc_Tsfc	if true, calculate surface temperature	T
capping	parameter associated with capping method of viscosities	1.0
capping_method	namelist to specify capping method	hibler
Cdn_atm	atmospheric drag coefficient
Cdn_ocn	ocean drag coefficient
Cf	ratio of ridging work to PE change in ridging
cgrid	vertical grid points for ice grid (compare bgrid)
char_len	length of character variable strings	80
char_len_long	length of longer character variable strings	256
check_step	time step on which to begin writing debugging data
check_umax	if true, check for ice speed \(>\) umax_stab
cldf	cloud fraction
cm_to_m	cm to meters conversion	0.01
coldice	value for constant albedo parameterization	0.70
coldsnow	value for constant albedo parameterization	0.81
conduct	conductivity parameterization
congel	basal ice growth	m
conserv_check	if true, check conservation
cosw	cosine of the turning angle in water
coszen	cosine of the zenith angle
Cp	proportionality constant for potential energy	kg/m\(^2\)/s\(^2\)
cpl_frazil	\(\bullet\) type of frazil ice coupling
cp_air	specific heat of air	1005.0 J/kg/K
cp_ice	specific heat of fresh ice	J/kg/K
cp_ocn	specific heat of sea water	J/kg/K
cp_wv	specific heat of water vapor	1.81x\(10^3\) J/kg/K
cp063	diffuse fresnel reflectivity (above)	0.063
cp455	diffuse fresnel reflectivity (below)	0.455
Cs	fraction of shear energy contributing to ridging	0.25
Cstar	constant in Hibler ice strength formula
cxm	combination of HTN values
cxp	combination of HTN values
cym	combination of HTE values
cyp	combination of HTE values
D
d_afsd_[proc]	change in FSD due to processes
daice_da	data assimilation concentration increment rate
daidtd	ice area tendency due to dynamics/transport	1/s
daidtt	ice area tendency due to thermodynamics	1/s
dalb_mlt	[see icepack_shortwave.F90]	-0.075
dalb_mlti	[see icepack_shortwave.F90]	-0.100
dalb_mltv	[see icepack_shortwave.F90]	-0.150
darcy_V	Darcy velocity used for brine height tracer
dardg1(n)dt	rate of fractional area loss by ridging ice (category n)	1/s
dardg2(n)dt	rate of fractional area gain by new ridges (category n)	1/s
daymo	number of days in one month
daycal	day number at end of month
days_per_year	number of days in one year	365
day_init	the initial day of the month
dbl_kind	definition of double precision	selected_real_kind(13)
debug_blocks	write extra diagnostics for blocks and decomposition	.false.
debug_forcing	write extra diagnostics for forcing inputs	.false.
debug_model	Logical that controls extended model point debugging.
debug_model_i	Local i gridpoint that defines debug_model point output.
debug_model_iblk	Local iblk value that defines debug_model point output.
debug_model_j	Local j gridpoint that defines debug_model point output.
debug_model_task	Local mpi task value that defines debug_model point output.
debug_model_step	Initial timestep for output from the debug_model flag.
Delta	function of strain rates (see Section Dynamics)	1/s
deltaminEVP	minimum value of Delta for EVP (see Section Dynamics)	1/s
deltaminVP	minimum value of Delta for VP (see Section Dynamics)	1/s
default_season	Season from which initial values of forcing are set.	winter
denom1	combination of constants for stress equation
depressT	ratio of freezing temperature to salinity of brine	0.054 deg/ppt
dhbr_bt	change in brine height at the bottom of the column
dhbr_top	change in brine height at the top of the column
dhsn	depth difference for snow on sea ice and pond ice
diag_file	diagnostic output file (alternative to standard out)
diag_type	where diagnostic output is written	stdout
diagfreq	how often diagnostic output is written (10 = once per 10 dt)
distrb	distribution data type
distrb_info	block distribution information
distribution_type	method used to distribute blocks on processors
distribution_weight	weighting method used to compute work per block
divu	strain rate I component, velocity divergence	1/s
divu_adv	divergence associated with advection	1/s
DminTarea	deltamin * tarea	m\(^2\)/s
dms	dimethyl sulfide concentration	mmol/m\(^3\)
dmsp	dimethyl sulfoniopropionate concentration	mmol/m\(^3\)
dpscale	time scale for flushing in permeable ice	\(1\times 10^{-3}\)
drhosdwind	wind compaction factor for snow	27.3 kg s/m\(^{4}\)
dragio	drag coefficient for water on ice	0.00536
dSdt_slow_mode	drainage strength parameter
dsnow	change in snow thickness	m
dt	thermodynamics time step	s
dt_dyn	dynamics/ridging/transport time step
dT_mlt	\(\Delta\) temperature per \(\Delta\) snow grain radius	deg
dte	subcycling time step for EVP dynamics (\(\Delta t_e\))	s
dte2T	dte / 2(damping time scale)
dtei	1/dte, where dte is the EVP subcycling time step	1/s
dump_file	output file for restart dump
dumpfreq	dump frequency for restarts, y, m, d, h or 1
dumpfreq_base	reference date for restart output, zero or init
dumpfreq_n	restart output frequency
dump_last	if true, write restart on last time step of simulation
dwavefreq	widths of wave frequency bins	1/s
dxE	width of E cell (\(\Delta x\)) through the middle	m
dxN	width of N cell (\(\Delta x\)) through the middle	m
dxT	width of T cell (\(\Delta x\)) through the middle	m
dxU	width of U cell (\(\Delta x\)) through the middle	m
dxhy	combination of HTE values
dyE	height of E cell (\(\Delta y\)) through the middle	m
dyN	height of N cell (\(\Delta y\)) through the middle	m
dyT	height of T cell (\(\Delta y\)) through the middle	m
dyU	height of U cell (\(\Delta y\)) through the middle	m
dyhx	combination of HTN values
dvidtd	ice volume tendency due to dynamics/transport	m/s
dvidtt	ice volume tendency due to thermodynamics	m/s
dvirdg(n)dt	ice volume ridging rate (category n)	m/s
E
e11, e12, e22	strain rate tensor components
earea	area of E-cell	m\(^2\)
ecci	yield curve minor/major axis ratio, squared	1/4
eice(n)	energy of melting of ice per unit area (in category n)	J/m\(^2\)
emask	land/boundary mask, T east edge (E-cell)
emissivity	emissivity of snow and ice	0.985
eps13	a small number	10\(^{-13}\)
eps16	a small number	10\(^{-16}\)
esno(n)	energy of melting of snow per unit area (in category n)	J/m\(^2\)
etax2	2 x eta (shear viscosity)	kg/s
evap	evaporative water flux	kg/m\(^2\)/s
ew_boundary_type	type of east-west boundary condition
elasticDamp	coefficient for calculating the parameter E, 0\(<\) elasticDamp \(<\)1	0.36
e_yieldcurve	yield curve minor/major axis ratio	2
e_plasticpot	plastic potential minor/major axis ratio	2
F
faero_atm	aerosol deposition rate	kg/m\(^2\)/s
faero_ocn	aerosol flux to the ocean	kg/m\(^2\)/s
fbot_xfer_type	type of heat transfer coefficient under ice
fcondtop(n)(_f)	conductive heat flux	W/m\(^2\)
fcor_blk	Coriolis parameter	1/s
ferrmax	max allowed energy flux error (thermodynamics)	1x \(10^{-3}\) W/m\(^2\)
ffracn	fraction of fsurfn used to melt pond ice
fhocn	net heat flux to ocean	W/m\(^2\)
fhocn_ai	grid-box-mean net heat flux to ocean (fhocn)	W/m\(^2\)
field_loc_center	field centered on grid cell	1
field_loc_Eface	field centered on east face	4
field_loc_NEcorner	field on northeast corner	2
field_loc_Nface	field centered on north face	3
field_loc_noupdate	ignore location of field	-1
field_loc_unknown	unknown location of field	0
field_loc_Wface	field centered on west face	5
field_type_angle	angle field type	3
field_type_noupdate	ignore field type	-1
field_type_scalar	scalar field type	1
field_type_unknown	unknown field type	0
field_type_vector	vector field type	2
first_ice	flag for initial ice formation
flat	latent heat flux	W/m\(^2\)
floediam	effective floe diameter for lateral melt	m
floeshape	floe shape constant for lateral melt	0.66
floe_rad_l	lower bounds for FSD size bins (radius)	m
floe_rad_c	centers of FSD size bins (radius)	m
floe_binwidth	width of FSD size bins (radius)	m
flux_bio	all biogeochemistry fluxes passed to ocean
flux_bio_ai	all biogeochemistry fluxes passed to ocean, grid cell mean
flw	incoming longwave radiation	W/m\(^2\)
flwout	outgoing longwave radiation	W/m\(^2\)
fmU	Coriolis parameter * mass in U cell	kg/s
formdrag	calculate form drag
fpond	fresh water flux to ponds	kg/m\(^2\)/s
fr_resp	bgc respiration fraction	0.05
frain	rainfall rate	kg/m\(^2\)/s
frazil	frazil ice growth	m
fresh	fresh water flux to ocean	kg/m\(^2\)/s
fresh_ai	grid-box-mean fresh water flux (fresh)	kg/m\(^2\)/s
frz_onset	day of year that freezing begins
frzmlt	freezing/melting potential	W/m\(^2\)
frzmlt_init	freezing/melting potential at beginning of time step	W/m\(^2\)
frzmlt_max	maximum magnitude of freezing/melting potential	W/m\(^2\)
frzpnd	Stefan refreezing of melt ponds	‘hlid’
fsalt	net salt flux to ocean	kg/m\(^2\)/s
fsalt_ai	grid-box-mean salt flux to ocean (fsalt)	kg/m\(^2\)/s
fsens	sensible heat flux	W/m\(^2\)
fsnow	snowfall rate	kg/m\(^2\)/s
fsnowrdg	snow fraction that survives in ridging	0.5
fsurf(n)(_f)	net surface heat flux excluding fcondtop	W/m\(^2\)
fsloss	rate of snow loss to leads	kg/m\(^{2}\) s
fsw	incoming shortwave radiation	W/m\(^2\)
fswabs	total absorbed shortwave radiation	W/m\(^2\)
fswfac	scaling factor to adjust ice quantities for updated data
fswint	shortwave absorbed in ice interior	W/m\(^2\)
fswpenl	shortwave penetrating through ice layers	W/m\(^2\)
fswthru	shortwave penetrating to ocean	W/m\(^2\)
fswthru_vdr	visible direct shortwave penetrating to ocean	W/m\(^2\)
fswthru_vdf	visible diffuse shortwave penetrating to ocean	W/m\(^2\)
fswthru_idr	near IR direct shortwave penetrating to ocean	W/m\(^2\)
fswthru_idf	near IR diffuse shortwave penetrating to ocean	W/m\(^2\)
fswthru_ai	grid-box-mean shortwave penetrating to ocean (fswthru)	W/m\(^2\)
fyear	current forcing data year
fyear_final	last forcing data year
fyear_init	initial forcing data year
G
gravit	gravitational acceleration	9.80616 m/s\(^2\)
grid_atm	grid structure for atm forcing/coupling fields, ‘A’, ‘B’, ‘C’, etc
grid_atm_dynu	grid for atm dynamic-u forcing/coupling fields, ‘T’, ‘U’, ‘N’, ‘E’
grid_atm_dynv	grid for atm dynamic-v forcing/coupling fields, ‘T’, ‘U’, ‘N’, ‘E’
grid_atm_thrm	grid for atm thermodynamic forcing/coupling fields, ‘T’, ‘U’, ‘N’, ‘E’
grid_file	input file for grid info
grid_format	format of grid files
grid_ice	structure of the model ice grid, ‘B’, ‘C’, etc
grid_ice_dynu	grid for ice dynamic-u model fields, ‘T’, ‘U’, ‘N’, ‘E’
grid_ice_dynv	grid for ice dynamic-v model fields, ‘T’, ‘U’, ‘N’, ‘E’
grid_ice_thrm	grid for ice thermodynamic model fields, ‘T’, ‘U’, ‘N’, ‘E’
grid_ocn	grid structure for ocn forcing/coupling fields, ‘A’, ‘B’, ‘C’, etc
grid_ocn_dynu	grid for ocn dynamic-u forcing/coupling fields, ‘T’, ‘U’, ‘N’, ‘E’
grid_ocn_dynv	grid for ocn dynamic-v forcing/coupling fields, ‘T’, ‘U’, ‘N’, ‘E’
grid_ocn_thrm	grid for ocn thermodynamic forcing/coupling fields, ‘T’, ‘U’, ‘N’, ‘E’
grid_type	‘rectangular’, ‘displaced_pole’, ‘column’ or ‘regional’
gridcpl_file	input file for coupling grid info
grow_net	specific biogeochemistry growth rate per grid cell	s \(^{-1}\)
Gstar	piecewise-linear ridging participation function parameter	0.15
H
halo_info	information for updating ghost cells
hfrazilmin	minimum thickness of new frazil ice	0.05 m
hi_min	minimum ice thickness for thinnest ice category	0.01 m
hi_ssl	ice surface scattering layer thickness	0.05 m
hicen	ice thickness in category n	m
highfreq	high-frequency atmo coupling	F
hin_old	ice thickness prior to growth/melt	m
hin_max	category thickness limits	m
hist_avg	if true, write averaged data instead of snapshots	T,T,T,T,T
histfreq	units of history output frequency: y, m, w, d or 1	m,x,x,x,x
histfreq_base	reference date for history output, zero or init
histfreq_n	integer output frequency in histfreq units	1,1,1,1,1
history_chunksize	history chunksizes in x,y directions (_format=’hdf5’ only)	0,0
history_deflate	compression level for history (_format=’hdf5’ only)	0
history_dir	path to history output files
history_file	history output file prefix
history_format	history file format
history_iotasks	history output total number of tasks used
history_precision	history output precision: 4 or 8 byte	4
history_rearranger	history output io rearranger method
history_root	history output io root task id
history_stride	history output io task stride
hist_time_axis	history file time axis interval location: begin, middle, end	end
hist_suffix	suffix to history_file in filename. x means no suffix	x,x,x,x,x
hm	land/boundary mask, thickness (T-cell)
hmix	ocean mixed layer depth	m
hour	hour of the year
hp0	pond depth at which shortwave transition to bare ice occurs	0.2 m
hp1	critical ice lid thickness for topo ponds (dEdd)	0.01 m
hpmin	minimum melt pond depth (shortwave)	0.005 m
hpondn	melt pond depth	m
hs_min	minimum thickness for which \(T_s\) is computed	1.\(\times\)10\(^{-4}\) m
hs0	snow depth at which transition to ice occurs (dEdd)	m
hs1	snow depth of transition to pond ice	0.03 m
hs_ssl	snow surface scattering layer thickness	0.04 m
Hstar	determines mean thickness of ridged ice	m
HTE	length of eastern edge (\(\Delta y\)) of T-cell	m
HTN	length of northern edge (\(\Delta x\)) of T-cell	m
HTS	length of southern edge (\(\Delta x\)) of T-cell	m
HTW	length of western edge of (\(\Delta y\)) T-cell	m
I
i(j)_glob	global domain location for each grid cell
i0vis	fraction of penetrating visible solar radiation	0.70
iblkp	block on which to write debugging data
i(j)block	Cartesian i,j position of block
ice_data_conc	ice initialization concentration, used mainly for box tests
ice_data_dist	ice initialization distribution, used mainly for box tests
ice_data_type	ice initialization mask, used mainly for box tests
ice_hist_field	type for history variables
ice_ic	choice of initial conditions (see Ice Initialization)
ice_stdout	unit number for standard output
ice_stderr	unit number for standard error output
ice_ref_salinity	reference salinity for ice–ocean exchanges
icells	number of grid cells with specified property (for vectorization)
iceruf	ice surface roughness at atmosphere interface	5.\(\times\)10\(^{-4}\) m
iceruf_ocn	under-ice roughness (at ocean interface)	0.03 m
iceEmask	dynamics ice extent mask (E-cell)
iceNmask	dynamics ice extent mask (N-cell)
iceTmask	dynamics ice extent mask (T-cell)
iceUmask	dynamics ice extent mask (U-cell)
idate	the date at the end of the current time step (yyyymmdd)
idate0	initial date
ierr	general-use error flag
igrid	interface points for vertical bio grid
i(j)hi	last i(j) index of physical domain (local)
i(j)lo	first i(j) index of physical domain (local)
incond_dir	directory to write snapshot of initial condition
incond_file	prefix for initial condition file name
int_kind	definition of an integer	selected_real_kind(6)
integral_order	polynomial order of quadrature integrals in remapping	3
ip, jp	local processor coordinates on which to write debugging data
istep	local step counter for time loop
istep0	number of steps taken in previous run	0
istep1	total number of steps at current time step
Iswabs	shortwave radiation absorbed in ice layers	W/m\(^2\)
J
K
kalg	absorption coefficient for algae
kappav	visible extinction coefficient in ice, wavelength\(<\)700nm	1.4 m\(^{-1}\)
kcatbound	category boundary formula
kdyn	type of dynamics (1 = EVP, 2 = EAP, 3 = VP, 0,-1 = off)	1
kg_to_g	kg to g conversion factor
kice	thermal conductivity of fresh ice ([4])	2.03 W/m/deg
kitd	type of itd conversions (0 = delta function, 1 = linear remap)	1
kmt_file	input file for land mask info
kmt_type	file, default, channel, wall, or boxislands	file
krdg_partic	ridging participation function	1
krdg_redist	ridging redistribution function	1
krgdn	mean ridge thickness per thickness of ridging ice
ksno	thermal conductivity of snow	0.30 W/m/deg
kstrength	ice stength formulation (1= [52], 0 = [15])	1
ktherm	thermodynamic formulation (-1 = off, 1 = [4], 2 = mushy)
L
l_brine	flag for brine pocket effects
l_fixed_area	flag for prescribing remapping fluxes
l_mpond_fresh	if true, retain (topo) pond water until ponds drain
latpnt	desired latitude of diagnostic points	degrees N
latt(u)_bounds	latitude of T(U) grid cell corners	degrees N
lcdf64	if true, use 64-bit  format
Lfresh	latent heat of melting of fresh ice = Lsub - Lvap	J/kg
lhcoef	transfer coefficient for latent heat
lmask_n(s)	northern (southern) hemisphere mask
local_id	local address of block in current distribution
log_kind	definition of a logical variable	kind(.true.)
lonpnt	desired longitude of diagnostic points	degrees E
lont(u)_bounds	longitude of T(U) grid cell corners	degrees E
Lsub	latent heat of sublimation for fresh water	2.835\(\times\) 10\(^6\) J/kg
ltripole_grid	flag to signal use of tripole grid
Lvap	latent heat of vaporization for fresh water	2.501\(\times\) 10\(^6\) J/kg
M
m_min	minimum mass for computing velocity	0.01 kg/m\(^2\)
m_to_cm	meters to cm conversion
m1	constant for lateral melt rate	1.6\(\times\)10\(^{-6}\) m/s deg\(^{-m2}\)
m2	constant for lateral melt rate	1.36
m2_to_km2	m\(^2\) to km\(^2\) conversion	1\(\times\)10\(^{-6}\)
maskhalo_bound	turns on bound_state halo masking
maskhalo_dyn	turns on dynamics halo masking
maskhalo_remap	turns on transport halo masking
master_task	task ID for the controlling processor
max_blocks	maximum number of blocks per processor
max_ntrcr	maximum number of tracers available	5
maxraft	maximum thickness of ice that rafts	m
mday	model day of the month
meltb	basal ice melt	m
meltl	lateral ice melt	m
melts	snow melt	m
meltsliq	snow melt mass	kg/m\(^{2}\)
meltsliqn	snow melt mass in category n	kg/m\(^{2}\)
meltt	top ice melt	m
min_salin	threshold for brine pockets	0.1 ppt
mlt_onset	day of year that surface melt begins
mmonth	model month number
monthp	previous month number
month_init	the initial month
mps_to_cmpdy	m per s to cm per day conversion	8.64\(\times\)10\(^6\)
msec	model seconds elasped into day
mtask	local processor number that writes debugging data
mu_rdg	e-folding scale of ridged ice
myear	model year
myear_max	maximum allowed model year
my_task	task ID for the current processor
N
n_aero	number of aerosol species
narea	area of N-cell	m\(^2\)
natmiter	number of atmo boundary layer iterations	5
nblocks	number of blocks on current processor
nblocks_tot	total number of blocks in decomposition
nblocks_x(y)	total number of blocks in x(y) direction
nbtrcr	number of biology tracers
ncat	number of ice categories	5
ncat_hist	number of categories written to history
ndte	number of subcycles	120
ndtd	number of dynamics/advection steps under thermo	1
new_day	flag for beginning new day
new_hour	flag for beginning new hour
new_month	flag for beginning new month
new_year	flag for beginning new year
nfreq	number of wave frequency bins	25
nfsd	number of floe size categories	12
nghost	number of rows of ghost cells surrounding each subdomain	1
ngroups	number of groups of flux triangles in remapping	5
nhlat	northern latitude of artificial mask edge	30\(^\circ\)S
nilyr	number of ice layers in each category	7
nit	nitrate concentration	mmol/m\(^3\)
nlt_bgc_[chem]	ocean sources and sinks for biogeochemistry
nmask	land/boundary mask, T north edge (N-cell)
nml_filename	namelist file name
nprocs	total number of processors
npt	total run length values associate with npt_unit
npt_unit	units of the run length, number set by npt
ns_boundary_type	type of north-south boundary condition
nslyr	number of snow layers in each category
nspint	number of solar spectral intervals
nstreams	number of history output streams (frequencies)
nt_<trcr>	tracer index
ntrace	number of fields being transported
ntrcr	number of tracers
nu_diag	unit number for diagnostics output file
nu_dump	unit number for dump file for restarting
nu_dump_eap	unit number for EAP dynamics dump file for restarting
nu_dump_[tracer]	unit number for tracer dump file for restarting
nu_forcing	unit number for forcing data file
nu_grid	unit number for grid file
nu_hdr	unit number for binary history header file
nu_history	unit number for history file
nu_kmt	unit number for land mask file
nu_nml	unit number for namelist input file
nu_restart	unit number for restart input file
nu_restart_eap	unit number for EAP dynamics restart input file
nu_restart_[tracer]	unit number for tracer restart input file
nu_rst_pointer	unit number for pointer to latest restart file
num_avail_hist_fields_[shape]	number of history fields of each array shape
nvar	number of horizontal grid fields written to history
nvarz	number of category, vertical grid fields written to history
nx(y)_block	total number of gridpoints on block in x(y) direction
nx(y)_global	number of physical gridpoints in x(y) direction, global domain
O
ocean_bio	concentrations of bgc constituents in the ocean
oceanmixed_file	data file containing ocean forcing data
oceanmixed_ice	if true, use internal ocean mixed layer
ocn_data_dir	directory for ocean forcing data
ocn_data_format	format of ocean forcing files
ocn_data_type	source of surface temperature, salinity data
omega	angular velocity of Earth	7.292\(\times\)10\(^{-5}\) rad/s
opening	rate of ice opening due to divergence and shear	1/s
P
p001	1/1000
p01	1/100
p025	1/40
p027	1/36
p05	1/20
p055	1/18
p1	1/10
p111	1/9
p15	15/100
p166	1/6
p2	1/5
p222	2/9
p25	1/4
p333	1/3
p4	2/5
p5	1/2
p52083	25/48
p5625m	-9/16
p6	3/5
p666	2/3
p75	3/4
phi_c_slow_mode	critical liquid fraction
phi_i_mushy	solid fraction at lower boundary
phi_sk	skeletal layer porosity
phi_snow	snow porosity for brine height tracer
pi	\(\pi\)
pi2	\(2\pi\)
pih	\(\pi /2\)
piq	\(\pi /4\)
pi(j,b,m)loc	x (y, block, task) location of diagnostic points
plat	grid latitude of diagnostic points
plon	grid longitude of diagnostic points
pndaspect	aspect ratio of pond changes (depth:area)	0.8
pointer_file	input file for restarting
potT	atmospheric potential temperature	K
PP_net	total primary productivity per grid cell	mg C/m\(^2\)/s
precip_units	liquid precipitation data units
print_global	if true, print global data	F
print_points	if true, print point data	F
processor_shape	descriptor for processor aspect ratio
Pstar	ice strength parameter	2.75\(\times\)10\(^4\)N/m\(^2\)
puny	a small positive number	1\(\times\)10\(^{-11}\)
Q
Qa	specific humidity at 10 m	kg/kg
qdp	deep ocean heat flux	W/m\(^2\)
qqqice	for saturated specific humidity over ice	1.16378\(\times\)10\(^7\)kg/m\(^3\)
qqqocn	for saturated specific humidity over ocean	6.275724\(\times\)10\(^6\)kg/m\(^3\)
Qref	2m atmospheric reference specific humidity	kg/kg
R
R_C2N	algal carbon to nitrate factor	mole/mole
R_gC2molC	mg/mmol carbon	12.01 mg/mole
R_chl2N	algal chlorophyll to nitrate factor	mg/mmol
R_ice	parameter for Delta-Eddington ice albedo
R_pnd	parameter for Delta-Eddington pond albedo
R_S2N	algal silicate to nitrate factor	0.03 mole/mole
R_snw	parameter for Delta-Eddington snow albedo
r16_kind	definition of quad precision	selected_real_kind(26)
Rac_rapid_mode	critical Rayleigh number	10
rad_to_deg	degree-radian conversion	\(180/\pi\)
radius	earth radius	6.37\(\times\)10\(^6\) m
rdg_conv	convergence for ridging	1/s
rdg_shear	shear for ridging	1/s
real_kind	definition of single precision real	selected_real_kind(6)
refindx	refractive index of sea ice	1.310
rep_prs	replacement pressure	N/m
revp	real(revised_evp)
restart	if true, initialize ice state from file	T
restart_age	if true, read age restart file
restart_bgc	if true, read bgc restart file
restart_chunksize	restart chunksizes in x,y directions (_format=’hdf5’ only)	0,0
restart_deflate	compression level for restart (_format=’hdf5’ only)	0
restart_dir	path to restart/dump files
restart_file	restart file prefix
restart_format	restart file format
restart_iotasks	restart output total number of tasks used
restart_rearranger	restart output io rearranger method
restart_root	restart output io root task id
restart_stride	restart output io task stride
restart_[tracer]	if true, read tracer restart file
restart_ext	if true, read/write halo cells in restart file
restart_coszen	if true, read/write coszen in restart file
restore_bgc	if true, restore nitrate/silicate to data
restore_ice	if true, restore ice state along lateral boundaries
restore_ocn	restore sst to data
revised_evp	if true, use revised EVP parameters and approach
rfracmin	minimum melt water fraction added to ponds	0.15
rfracmax	maximum melt water fraction added to ponds	1.0
rhoa	air density	kg/m\(^3\)
rhofresh	density of fresh water	1000.0 kg/m\(^3\)
rhoi	density of ice	kg/m\(^3\)
rhos	density of snow	kg/m\(^3\)
rhos_cmp	density of snow due to wind compaction	kg/m\(^3\)
rhos_cnt	density of ice and liquid content of snow	kg/m\(^3\)
rhosi	average sea ice density (for hbrine tracer)	kg/m\(^3\)
rhosmax	maximum snow density	450 kg/m\(^{3}\)
rhosmin	minimum snow density	100 kg/m\(^{3}\)
rhosnew	new snow density	100 kg/m\(^{3}\)
rhow	density of seawater	kg/m\(^3\)
rnilyr	real(nlyr)
rside	fraction of ice that melts laterally
rsnw	snow grain radius	10\(^{-6}\) m
rsnw_fall	freshly fallen snow grain radius	\(\times\) 10\(^{-6}\) m
rsnw_mlt	melting snow grain radius	\(\times\) 10\(^{-6}\) m
rsnw_nonmelt	nonmelting snow grain radius	\(\times\) 10\(^{-6}\) m
rsnw_sig	standard deviation of snow grain radius	\(\times\) 10\(^{-6}\) m
rsnw_tmax	maximum snow radius	\(\times\) 10\(^{-6}\) m
runid	identifier for run
runtype	type of initialization used
S
s11, s12, s22	stress tensor components
saltmax	max salinity, at ice base ([4])	3.2 ppt
scale_factor	scaling factor for shortwave radiation components
seabed_stress	if true, calculate seabed stress	F
seabed_stress_method	method for calculating seabed stress (‘LKD’ or ‘probabilistic’)	LKD
secday	number of seconds in a day
sec_init	the initial second
shcoef	transfer coefficient for sensible heat
shear	strain rate II component	1/s
shlat	southern latitude of artificial mask edge	30\(^\circ\)N
shortwave	flag for shortwave parameterization (‘ccsm3’ or ‘dEdd’ or ‘dEdd_snicar_ad’)
sig1(2)	principal stress components \(\sigma_{n,1}\), \(\sigma_{n,2}\) (diagnostic)
sigP	internal ice pressure	N/m
sil	silicate concentration	mmol/m\(^3\)
sinw	sine of the turning angle in water
Sinz	ice salinity profile	ppt
sk_l	skeletal layer thickness	0.03 m
snoice	snow–ice formation	m
snowpatch	length scale for parameterizing nonuniform snow coverage	0.02 m
skl_bgc	biogeochemistry on/off
smassice	mass of ice in snow from smice tracer	kg/m\(^2\)
smassliq	mass of liquid in snow from smliq tracer	kg/m\(^2\)
snowage_drdt0	initial rate of change of effective snow radius
snowage_rhos	snow aging parameter (density)
snowage_kappa	snow aging best-fit parameter
snowage_tau	snow aging best-fit parameter
snowage_T	snow aging parameter (temperature)
snowage_Tgrd	snow aging parameter (temperature gradient)
snw_aging_table	snow aging lookup table
snw_filename	snowtable filename
snw_tau_fname	snowtable file tau fieldname
snw_kappa_fname	snowtable file kappa fieldname
snw_drdt0_fname	snowtable file drdt0 fieldname
snw_rhos_fname	snowtable file rhos fieldname
snw_Tgrd_fname	snowtable file Tgrd fieldname
snw_T_fname	snowtable file T fieldname
snwgrain	activate snow metamorphosis
snwlvlfac	fractional increase in snow depth for redistribution on ridges	0.3
snwredist	type of snow redistribution
spval	special value (single precision)	\(10^{30}\)
spval_dbl	special value (double precision)	\(10^{30}\)
ss_tltx(y)	sea surface in the x(y) direction	m/m
sss	sea surface salinity	ppt
sst	sea surface temperature	C
Sswabs	shortwave radiation absorbed in snow layers	W/m\(^2\)
stefan-boltzmann	Stefan-Boltzmann constant	5.67\(\times\)10\(^{-8}\) W/m\(^2\)K\(^4\)
stop_now	if 1, end program execution
strairx(y)U	stress on ice by air in the x(y)-direction (centered in U cell)	N/m\(^2\)
strairx(y)T	stress on ice by air, x(y)-direction (centered in T cell)	N/m\(^2\)
strax(y)	wind stress components from data	N/m\(^2\)
strength	ice strength	N/m
stress12	internal ice stress, \(\sigma_{12}\)	N/m
stressm	internal ice stress, \(\sigma_{11}-\sigma_{22}\) (\(\sigma_2\) in the doc)	N/m
stressp	internal ice stress, \(\sigma_{11}+\sigma_{22}\) (\(\sigma_1\) in the doc)	N/m
strintx(y)U	divergence of internal ice stress, x(y)	N/m\(^2\)
strocnx(y)U	ice–ocean stress in the x(y)-direction (U-cell)	N/m\(^2\)
strocnx(y)T	ice–ocean stress, x(y)-dir. (T-cell)	N/m\(^2\)
strtltx(y)U	surface stress due to sea surface slope	N/m\(^2\)
swv(n)dr(f)	incoming shortwave radiation, visible (near IR), direct (diffuse)	W/m\(^2\)
T
Tair	air temperature at 10 m	K
tarea	area of T-cell	m\(^2\)
tarean	area of northern hemisphere T-cells	m\(^2\)
tarear	1/tarea	1/m\(^2\)
tareas	area of southern hemisphere T-cells	m\(^2\)
tcstr	string identifying T grid for history variables
Tf	freezing temperature	C
Tffresh	freezing temp of fresh ice	273.15 K
tfrz_option	form of ocean freezing temperature
saltflux_option	form of coupled salt flux
thinS	minimum ice thickness for brine tracer
timer_stats	logical to turn on extra timer statistics	.false.
timesecs	total elapsed time in seconds	s
time_beg	beginning time for history averages
time_bounds	beginning and ending time for history averages
time_end	ending time for history averages
time_forc	time of last forcing update	s
Timelt	melting temperature of ice top surface	C
Tinz	Internal ice temperature	C
TLAT	latitude of cell center	radians
Tliquidus_max	maximum liquidus temperature of mush	C
TLON	longitude of cell center	radians
tmask	land/boundary mask, thickness (T-cell)
tmass	total mass of ice and snow	kg/m\(^2\)
Tmin	minimum allowed internal temperature	-100. C
Tmltz	melting temperature profile of ice
Tocnfrz	temperature of constant freezing point parameterization	-1.8 C
tr_aero	if true, use aerosol tracers
tr_bgc_[tracer]	if true, use biogeochemistry tracers
tr_brine	if true, use brine height tracer
tr_FY	if true, use first-year area tracer
tr_iage	if true, use ice age tracer
tr_lvl	if true, use level ice area and volume tracers
tr_pond_lvl	if true, use level-ice melt pond scheme
tr_pond_topo	if true, use topo melt pond scheme
trcr	ice tracers
trcr_depend	tracer dependency on basic state variables
Tref	2m atmospheric reference temperature	K
trestore	restoring time scale	days
tripole	if true, block lies along tripole boundary
tripoleT	if true, tripole boundary is T-fold; if false, U-fold
Tsf_errmax	max allowed \(T_{\mathit sf}\) error (thermodynamics)	5.\(\times\)10\(^{-4}\)deg
Tsfc(n)	temperature of ice/snow top surface (in category n)	C
Tsnz	Internal snow temperature	C
Tsmelt	melting temperature of snow top surface	C
TTTice	for saturated specific humidity over ice	5897.8 K
TTTocn	for saturated specific humidity over ocean	5107.4 K
U
uarea	area of U-cell	m \(^2\)
uarear	1/uarea	m \(^{-2}\)
uatm	wind velocity in the x direction	m/s
ULAT	latitude of U-cell centers	radians
ULON	longitude of U-cell centers	radians
umask	land/boundary mask, velocity corner (U-cell)
umax_stab	ice speed threshold (diagnostics)	m/s
umin	min wind speed for turbulent fluxes	m/s
uocn	ocean current in the x-direction	m/s
update_ocn_f	if true, include frazil ice fluxes in ocean flux fields
use_leap_years	if true, include leap days
use_restart_time	if true, use date from restart file
use_smliq_pnd	use liquid in snow for ponds
ustar_min	minimum friction velocity under ice
ucstr	string identifying U grid for history variables
uvel	x-component of ice velocity	m/s
uvel_init	x-component of ice velocity at beginning of time step	m/s
uvm	land/boundary mask, velocity (U-cell)
V
vatm	wind velocity in the y direction	m/s
vice(n)	volume per unit area of ice (in category n)	m
vicen_init	ice volume at beginning of timestep	m
viscosity_dyn	dynamic viscosity of brine	\(1.79\times 10^{-3}\) kg/m/s
visc_method	method for calculating viscosities (‘avg_strength’ or ‘avg_zeta’)	avg_zeta
vocn	ocean current in the y-direction	m/s
vonkar	von Karman constant	0.4
vort	vorticity	1/s
vraftn	volume of rafted ice	m
vrdgn	volume of ridged ice	m
vredistrn	redistribution function: fraction of new ridge volume
vsno(n)	volume per unit area of snow (in category n)	m
vvel	y-component of ice velocity	m/s
vvel_init	y-component of ice velocity at beginning of time step	m/s
W
warmice	value for constant albedo parameterization	0.68
warmsno	value for constant albedo parameterization	0.77
wave_sig_ht	significant height of waves	m
wave_spectrum	wave spectrum	m\(^2\)/s
wavefreq	wave frequencies	1/s
wind	wind speed	m/s
windmin	minimum wind speed to compact snow	10 m/s
write_history	if true, write history now
write_ic	if true, write initial conditions
write_restart	if 1, write restart now
X
Y
ycycle	number of years in forcing data cycle
yday	day of the year, computed in the model calendar
yield_curve	type of yield curve	ellipse
yieldstress11(12, 22)	yield stress tensor components
year_init	the initial year
Z
zetax2	2 x zeta (bulk viscosity)	kg/s
zlvl	atmospheric level height (momentum)	m
zlvs	atmospheric level height (scalars)	m
zref	reference height for stability	m
zTrf	reference height for \(T_{ref}\), \(Q_{ref}\), \(U_{ref}\)	m
zvir	gas constant (water vapor)/gas constant (air) - 1	0.606
Deprecated options and parameters
heat_capacity	if true, use salinity-dependent thermodynamics	T
kseaice	thermal conductivity of ice for zero-layer thermodynamics	2.0 W/m/deg
ktherm	thermodynamic formulation (0 = zero-layer, 1 = [4], 2 = mushy)
tr_pond_cesm	if true, use CESM melt pond scheme