C $Header: /u/gcmpack/MITgcm/pkg/seaice/SEAICE_OPTIONS.h,v 1.81 2017/04/28 17:20:33 mlosch Exp $ C $Name: $ C *==========================================================* C | SEAICE_OPTIONS.h C | o CPP options file for sea ice package. C *==========================================================* C | Use this file for selecting options within the sea ice C | package. C *==========================================================* #ifndef SEAICE_OPTIONS_H #define SEAICE_OPTIONS_H #include "PACKAGES_CONFIG.h" #include "CPP_OPTIONS.h" #ifdef ALLOW_SEAICE C Package-specific Options & Macros go here C-- Write "text-plots" of certain fields in STDOUT for debugging. #undef SEAICE_DEBUG C-- Allow sea-ice dynamic code. C This option is provided to allow use of TAMC C on the thermodynamics component of the code only. C Sea-ice dynamics can also be turned off at runtime C using variable SEAICEuseDYNAMICS. #define SEAICE_ALLOW_DYNAMICS C-- By default, the sea-ice package uses its own integrated bulk C formulae to compute fluxes (fu, fv, EmPmR, Qnet, and Qsw) over C open-ocean. When this flag is set, these variables are computed C in a separate external package, for example, pkg/exf, and then C modified for sea-ice effects by pkg/seaice. #define SEAICE_EXTERNAL_FLUXES C-- Exclude Wind-Stress common block (in SEAICE.h). This option C should ALWAYS been left undef (just listed here for the record) #undef SEAICE_EXCLUDE_WIND_STRESS C-- This CPP flag has been retired. The number of ice categories C used to solve for seaice flux is now specified by run-time C parameter SEAICE_multDim. C Note: be aware of pickup_seaice.* compatibility issues when C restarting a simulation with a different number of categories. c#define SEAICE_MULTICATEGORY C-- run with sea Ice Thickness Distribution (ITD); C set number of categories (nITD) in SEAICE_SIZE.h #undef SEAICE_ITD C-- Since the missing sublimation term is now included C this flag is needed for backward compatibility #undef SEAICE_DISABLE_SUBLIM C-- Suspected missing term in coupled ocn-ice heat budget (to be confirmed) #undef SEAICE_DISABLE_HEATCONSFIX C-- Default is constant seaice salinity (SEAICE_salt0); Define the following C flag to consider (space & time) variable salinity: advected and forming C seaice with a fraction (=SEAICE_saltFrac) of freezing seawater salinity. C- Note: SItracer also offers an alternative way to handle variable salinity. #undef SEAICE_VARIABLE_SALINITY C-- Tracers of ice and/or ice cover. #undef ALLOW_SITRACER #ifdef ALLOW_SITRACER C-- To try avoid 'spontaneous generation' of tracer maxima by advdiff. # define ALLOW_SITRACER_ADVCAP #endif C-- Enable grease ice parameterization C The grease ice parameterization delays formation of solid C sea ice from frazil ice by a time constant and provides a C dynamic calculation of the initial solid sea ice thickness C HO as a function of winds, currents and available grease ice C volume. Grease ice does not significantly reduce heat loss C from the ocean in winter and area covered by grease is thus C handled like open water. C (For details see Smedsrud and Martin, 2014, Ann.Glac.) C Set SItrName(1) = 'grease' in namelist SEAICE_PARM03 in data.seaice C then output SItr01 is SItrNameLong(1) = 'grease ice volume fraction', C with SItrUnit(1) = '[0-1]', which needs to be multiplied by SIheff C to yield grease ice volume. Additionally, the actual grease ice C layer thickness (diagnostic SIgrsLT) can be saved. #undef SEAICE_GREASE C-- grease ice uses SItracer: #ifdef SEAICE_GREASE # define ALLOW_SITRACER # define ALLOW_SITRACER_ADVCAP #endif C-- By default the seaice model is discretized on a B-Grid (for C historical reasons). Define the following flag to use a new C (not thoroughly) test version on a C-grid #define SEAICE_CGRID C-- Only for the C-grid version it is possible to #ifdef SEAICE_CGRID C enable advection of sea ice momentum # undef SEAICE_ALLOW_MOM_ADVECTION C enable JFNK code by defining the following flag # define SEAICE_ALLOW_JFNK C enable Krylov code by defining the following flag # define SEAICE_ALLOW_KRYLOV C enable LSR to use global (multi-tile) tri-diagonal solver # undef SEAICE_GLOBAL_3DIAG_SOLVER C enable EVP code by defining the following flag # define SEAICE_ALLOW_EVP # ifdef SEAICE_ALLOW_EVP C-- When set use SEAICE_zetaMin and SEAICE_evpDampC to limit viscosities C from below and above in seaice_evp: not necessary, and not recommended # undef SEAICE_ALLOW_CLIPZETA # endif /* SEAICE_ALLOW_EVP */ C smooth regularization (without max-function) of delta for C better differentiability # undef SEAICE_DELTA_SMOOTHREG C regularize zeta to zmax with a smooth tanh-function instead C of a min(zeta,zmax). This improves convergence of iterative C solvers (Lemieux and Tremblay 2009, JGR). No effect on EVP # undef SEAICE_ZETA_SMOOTHREG C allow the truncated ellipse rheology (runtime flag SEAICEuseTEM) # undef SEAICE_ALLOW_TEM C Use LSR vector code; not useful on non-vector machines, because it C slows down convergence considerably, but the extra iterations are C more than made up by the much faster code on vector machines. For C the only regularly test vector machine these flags a specified C in the build options file SUPER-UX_SX-8_sxf90_awi, so that we comment C them out here. # undef SEAICE_VECTORIZE_LSR C Use zebra-method (alternate lines) for line-successive-relaxation C This modification improves the convergence of the vector code C dramatically, so that is may actually be useful in general, but C that needs to be tested. Can be used without vectorization options. # undef SEAICE_LSR_ZEBRA C Use parameterisation of grounding ice for a better representation C of fastice in shallow seas # undef SEAICE_ALLOW_BOTTOMDRAG #else /* not SEAICE_CGRID, but old B-grid */ C-- By default for B-grid dynamics solver wind stress under sea-ice is C set to the same value as it would be if there was no sea-ice. C Define following CPP flag for B-grid ice-ocean stress coupling. # define SEAICE_BICE_STRESS C-- By default for B-grid dynamics solver surface tilt is obtained C indirectly via geostrophic velocities. Define following CPP C in order to use ETAN instead. # define EXPLICIT_SSH_SLOPE C-- Defining this flag turns on FV-discretization of the B-grid LSOR solver. C It is smoother and includes all metric terms, similar to C-grid solvers. C It is here for completeness, but its usefulness is unclear. # undef SEAICE_LSRBNEW #endif /* SEAICE_CGRID */ C-- When set limit the Ice-Loading to mass of 1/5 of Surface ocean grid-box #undef SEAICE_CAP_ICELOAD C-- When set use SEAICE_clipVelocties = .true., to clip U/VICE at 40cm/s, C not recommended #undef SEAICE_ALLOW_CLIPVELS C-- When set cap the sublimation latent heat flux in solve4temp according C to the available amount of ice+snow. Otherwise this term is treated C like all of the others -- residuals heat and fw stocks are passed to C the ocean at the end of seaice_growth in a conservative manner. C SEAICE_CAP_SUBLIM is not needed as of now, but kept just in case. #undef SEAICE_CAP_SUBLIM C-- Enable free drift code #undef SEAICE_ALLOW_FREEDRIFT C-- pkg/seaice cost functions compile flags c >>> Sea-ice volume (requires pkg/cost) #undef ALLOW_COST_ICE c >>> Sea-ice misfit to obs (requires pkg/cost and ecco) #undef ALLOW_SEAICE_COST_SMR_AREA #endif /* ALLOW_SEAICE */ #endif /* SEAICE_OPTIONS_H */ CEH3 ;;; Local Variables: *** CEH3 ;;; mode:fortran *** CEH3 ;;; End: ***