Contact: Michael Winton (mw)
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Sea Ice Simulator (SIS) is a dynamics/thermodynamic sea ice model for use in coupled models
under FMS. SIS calculates the concentration, thickness, temperature, brine content, and snow
cover of an arbitrary number of ice thickness categories (including open water) as well as
the motion of the complete pack.
SIS employs a three layer scheme similar to Semtner's for the vertical thermodynamics.
Multiple ice thickness categories are maintained. A simple scheme moves ice between
categories when category thickness bounds are transgressed due to thermodynamic or dynamic
changes. The model contains full dynamics with internal ice forces calculated using an
elastic-viscous-plastic rheology. For more details see the technical document. Within FMS
coupled models, the ocean and atmosphere models never interact directly with each other.
The sea ice model plays the role of a general interface between the two. The ocean surface
albedo and roughnesses are provided by the sea ice model.
Modules external to SIS:
use ice_model_mod, only : ice_model_init, ice_bottom_to_ice_top, update_ice_model_fast,
update_ice_model_slow, ice_model_end, ice_data_type
Reads ice_model_nml namelist input. Sets up ice grid configuration. Initializes prognostic variables (from restart file, if available). Initializes diagnostics.
Supplies surface albedo and roughnesses.
Calculates ice temperature changes. Accumulates heat and water fluxes for use in update_ice_model_slow.
Calculates ice and snow mass changes. Calculates ice motion. Transports ice and snow. Adjusts thickness distribution. Prepares fluxes for ocean surface.
Writes prognostic variables to restart file.
Contains the state of the ice model including fields used for coupling.
type(domain2D) Ice%Domain The coupler uses the ice domain for mapping between grids and processors real, dimension(:,:,:) Ice%part_size fractional area of each partition of a temperature grid box the following fields are for communication from the ice to the atmosphere Ice%t_surf surface temperature (deg k) Ice%albedo surface albedo (fraction) Ice%rough_mom surface roughness for momentum (m) Ice%rough_heat surface roughness for heat (m) Ice%rough_moist surface roughness for moisture (m) Ice%u_surf zonal (ocean/ice) current at the surface (m/s) Ice%v_surf meridional (ocean/ice) current at the surface (m/s) the following fields are for communication from the ice to the ocean Ice%flux_u zonal wind stress (Pa) Ice%flux_v meridional wind stress (Pa) Ice%p_surf pressure of overlying ice and atmosphere on ocean surface (Pa) Ice%flux_t sensible heat flux (w/m2) Ice%flux_q specific humidity flux (kg/m2/s) Ice%flux_sw net (down-up) shortwave flux (w/m2) Ice%flux_lw net (down-up) longwave flux (w/m2) Ice%lprec mass flux of liquid precipitation (Kg/m2/s) Ice%fprec mass flux of frozen precipitation (Kg/m2/s) Ice%runoff mass flux of liquid runoff (Kg/m2/s) Ice%calving mass flux of frozen runoff (Kg/m2/s)
A detailed description of public routines (all arguments
must be described including their units, type, and dimensions).
kmelt 5.8e-5*4.2e6 ocean/ice heat flux constant heat_rough_ice 1.0e-4 heat roughness length mom_rough_ice 1.0e-4 momentum same, cd10=(von_k/ln(10/z0))^2 alb_sno 0.80 snow albedo (0.05 less if melting) alb_ice 0.65 ice albedo (0.05 less if melting) pen_ice 0.3 part unreflected solar penetrates ice opt_dep_ice 0.67 ice optical depth ice_bulk_salin 0.0 ice bulk salinity (for ocean salt flux) p0 2.75e4 ice strength parameter c0 20.0 another ice strength parameter cdw 3.24e-3 water/ice drag coefficient wd_turn 25.0 water/ice drag turning angle nsteps_dyn 432 dynamics steps per slow timestep nsteps_adv 8 advection steps per slow timestep atmos_winds .true. wind stress from atmosphere model over t points and has wrong sign slab_ice .false. do old-style GFDL slab ice? spec_ice .false. old-style GFDL slab ice with SST, ice thickness and conc. from data num_part 6 number of ice grid partitions (partition 1 is open water)
MOI ice modeled 0 or 1 MI ice mass Kg/m^2 CN ice concentration 0-1 HS snow thickness m-snow HI ice thickness m-ice T1 upper ice layer temperature C T2 lower ice layer temperature C TS surface temperature C SH sensible heat flux W/m^2 LH latent heat flux W/m^2 SW short wave heat flux W/m^2 LW long wave heat flux over ice W/m^2 SNOWFL rate of snow fall Kg/m^2/s RAIN rate of rain fall Kg/m^2/s RUNOFF liquid runoff Kg/m^2/s CALVING frozen runoff Kg/m^2/s EVAP evaporation Kg/m^2/s SALTF ice to ocean salt flux Kg/m^2/s SN2IC rate of snow to ice conversion Kg/m^2/s TMELT upper surface melting energy flux W/m^2 BMELT bottom surface melting energy flux W/m^2 BHEAT ocean to ice heat flux W/m^2 E2MELT heat needed to melt ice J/m^2 FRAZIL energy flux of frazil formation W/m^2 ALB surface albedo 0-1 XPRT frozen water transport convergence Kg/m^2/yr LSRC frozen water local source Kg/m^2/yr LSNK frozen water local sink Kg/m^2/yr BSNK frozen water local bottom sink Kg/m^2/yr STRAIN_ANGLE strain angle none SIGI first stress invariant none SIGII second stress invariant none STRENGTH ice strength Pa*m UI ice velocity - x component m/s VI ice velocity - y component m/s FA_X air stress on ice - x component Pa FA_Y air stress on ice - y component Pa FI_X ice internal stress - x component Pa FI_Y ice internal stress - y component Pa FC_X coriolis force - x component Pa FC_Y coriolis force - y component Pa FW_X water stress on ice - x component Pa FW_Y water stress on ice - y component Pa UO surface current - x component m/s VO surface current - y component m/s
Data sets used.
Revision history
A list of error messages by routine and what it means.
A list of references.
A list of compiler recommendations (might include recommended
compiler version or optimization options for a particular
system).
A list of precompiler options.
A list of loader options (e.g., libraries) and/or
recommendations (note that this may be machine dependent).
A list of known bugs.
Developer notes.
Future plans.