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C $Header: /u/gcmpack/MITgcm/pkg/shelfice/shelfice_thermodynamics.F,v 1.38 2014/11/02 21:23:51 gforget Exp $ |
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C $Name: $ |
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|
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#include "SHELFICE_OPTIONS.h" |
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#ifdef ALLOW_AUTODIFF |
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# include "AUTODIFF_OPTIONS.h" |
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#endif |
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#ifdef ALLOW_CTRL |
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# include "CTRL_OPTIONS.h" |
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#endif |
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#ifdef ALLOW_STREAMICE |
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# include "STREAMICE_OPTIONS.h" |
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#endif |
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|
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|
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CBOP |
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C !ROUTINE: SHELFICE_THERMODYNAMICS |
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C !INTERFACE: |
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SUBROUTINE SHELFICE_THERMODYNAMICS( |
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I myTime, myIter, myThid ) |
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C !DESCRIPTION: \bv |
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C *=============================================================* |
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C | S/R SHELFICE_THERMODYNAMICS |
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C | o shelf-ice main routine. |
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C | compute temperature and (virtual) salt flux at the |
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C | shelf-ice ocean interface |
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C | |
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C | stresses at the ice/water interface are computed in separate |
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C | routines that are called from mom_fluxform/mom_vecinv |
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C *=============================================================* |
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|
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C !USES: |
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IMPLICIT NONE |
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|
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C === Global variables === |
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#include "SIZE.h" |
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#include "EEPARAMS.h" |
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#include "PARAMS.h" |
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#include "GRID.h" |
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#include "DYNVARS.h" |
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#include "FFIELDS.h" |
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#include "SHELFICE.h" |
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#include "SHELFICE_COST.h" |
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#ifdef ALLOW_AUTODIFF |
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# include "CTRL_SIZE.h" |
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# include "ctrl.h" |
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# include "ctrl_dummy.h" |
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#endif /* ALLOW_AUTODIFF */ |
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#ifdef ALLOW_AUTODIFF_TAMC |
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# ifdef SHI_ALLOW_GAMMAFRICT |
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# include "tamc.h" |
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# include "tamc_keys.h" |
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# endif /* SHI_ALLOW_GAMMAFRICT */ |
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#endif /* ALLOW_AUTODIFF_TAMC */ |
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#ifdef ALLOW_STREAMICE |
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# include "STREAMICE.h" |
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#endif |
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|
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|
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C !INPUT/OUTPUT PARAMETERS: |
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C === Routine arguments === |
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C myIter :: iteration counter for this thread |
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C myTime :: time counter for this thread |
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C myThid :: thread number for this instance of the routine. |
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_RL myTime |
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INTEGER myIter |
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INTEGER myThid |
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CEOP |
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|
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#ifdef ALLOW_SHELFICE |
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C !LOCAL VARIABLES : |
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C === Local variables === |
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C I,J,K,Kp1,bi,bj :: loop counters |
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C tLoc, sLoc, pLoc :: local in-situ temperature, salinity, pressure |
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C theta/saltFreeze :: temperature and salinity of water at the |
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C ice-ocean interface (at the freezing point) |
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C freshWaterFlux :: local variable for fresh water melt flux due |
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C to melting in kg/m^2/s |
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C (negative density x melt rate) |
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C convertFW2SaltLoc:: local copy of convertFW2Salt |
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C cFac :: 1 for conservative form, 0, otherwise |
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C rFac :: realFreshWaterFlux factor |
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C dFac :: 0 for diffusive heat flux (Holland and Jenkins, 1999, eq21) |
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C 1 for advective and diffusive heat flux (eq22, 26, 31) |
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C fwflxFac :: only effective for dFac=1, 1 if we expect a melting fresh |
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C water flux, 0 otherwise |
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C auxiliary variables and abbreviations: |
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C a0, a1, a2, b, c0 |
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C eps1, eps2, eps3, eps3a, eps4, eps5, eps6, eps7, eps8 |
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C aqe, bqe, cqe, discrim, recip_aqe |
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C drKp1, recip_drLoc |
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INTEGER I,J,K,Kp1 |
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INTEGER bi,bj |
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_RL tLoc(1:sNx,1:sNy) |
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_RL sLoc(1:sNx,1:sNy) |
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_RL pLoc(1:sNx,1:sNy) |
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_RL uLoc(1:sNx,1:sNy) |
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_RL vLoc(1:sNx,1:sNy) |
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_RL thetaFreeze, saltFreeze, recip_Cp |
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_RL freshWaterFlux, convertFW2SaltLoc |
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_RL a0, a1, a2, b, c0 |
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_RL eps1, eps2, eps3, eps3a, eps4, eps5, eps6, eps7, eps8 |
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_RL cFac, rFac, dFac, fwflxFac |
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_RL aqe, bqe, cqe, discrim, recip_aqe |
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_RL drKp1, recip_drLoc |
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_RL tmpFac |
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|
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#ifdef SHI_ALLOW_GAMMAFRICT |
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_RL shiPr, shiSc, shiLo, recip_shiKarman, shiTwoThirds |
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_RL gammaTmoleT, gammaTmoleS, gammaTurb, gammaTurbConst |
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_RL ustar, ustarSq, etastar |
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PARAMETER ( shiTwoThirds = 0.66666666666666666666666666667D0 ) |
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#endif |
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|
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#ifndef ALLOW_OPENAD |
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_RL SW_TEMP |
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EXTERNAL SW_TEMP |
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#endif |
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|
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#ifdef ALLOW_SHIFWFLX_CONTROL |
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_RL xx_shifwflx_loc(1-olx:snx+olx,1-oly:sny+oly,nsx,nsy) |
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#endif |
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C---+----1----+----2----+----3----+----4----+----5----+----6----+----7-|--+----| |
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|
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#ifdef SHI_ALLOW_GAMMAFRICT |
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#ifdef ALLOW_AUTODIFF |
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C re-initialize here again, curtesy to TAF |
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DO bj = myByLo(myThid), myByHi(myThid) |
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DO bi = myBxLo(myThid), myBxHi(myThid) |
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DO J = 1-OLy,sNy+OLy |
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DO I = 1-OLx,sNx+OLx |
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shiTransCoeffT(i,j,bi,bj) = SHELFICEheatTransCoeff |
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shiTransCoeffS(i,j,bi,bj) = SHELFICEsaltTransCoeff |
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ENDDO |
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ENDDO |
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ENDDO |
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ENDDO |
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#endif /* ALLOW_AUTODIFF */ |
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IF ( SHELFICEuseGammaFrict ) THEN |
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C Implement friction velocity-dependent transfer coefficient |
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C of Holland and Jenkins, JPO, 1999 |
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recip_shiKarman= 1. _d 0 / 0.4 _d 0 |
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shiLo = 0. _d 0 |
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shiPr = shiPrandtl**shiTwoThirds |
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shiSc = shiSchmidt**shiTwoThirds |
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cph shiPr = (viscArNr(1)/diffKrNrT(1))**shiTwoThirds |
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cph shiSc = (viscArNr(1)/diffKrNrS(1))**shiTwoThirds |
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gammaTmoleT = 12.5 _d 0 * shiPr - 6. _d 0 |
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gammaTmoleS = 12.5 _d 0 * shiSc - 6. _d 0 |
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C instead of etastar = sqrt(1+zetaN*ustar./(f*Lo*Rc)) |
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etastar = 1. _d 0 |
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gammaTurbConst = 1. _d 0 / (2. _d 0 * shiZetaN*etastar) |
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& - recip_shiKarman |
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#ifdef ALLOW_AUTODIFF |
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DO bj = myByLo(myThid), myByHi(myThid) |
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DO bi = myBxLo(myThid), myBxHi(myThid) |
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DO J = 1-OLy,sNy+OLy |
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DO I = 1-OLx,sNx+OLx |
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shiTransCoeffT(i,j,bi,bj) = 0. _d 0 |
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shiTransCoeffS(i,j,bi,bj) = 0. _d 0 |
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ENDDO |
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ENDDO |
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ENDDO |
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ENDDO |
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#endif /* ALLOW_AUTODIFF */ |
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ENDIF |
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#endif /* SHI_ALLOW_GAMMAFRICT */ |
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|
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C are we doing the conservative form of Jenkins et al. (2001)? |
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recip_Cp = 1. _d 0 / HeatCapacity_Cp |
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cFac = 0. _d 0 |
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IF ( SHELFICEconserve ) cFac = 1. _d 0 |
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C with "real fresh water flux" (affecting ETAN), |
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C there is more to modify |
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rFac = 1. _d 0 |
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IF ( SHELFICEconserve .AND. useRealFreshWaterFlux ) rFac = 0. _d 0 |
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C heat flux into the ice shelf, default is diffusive flux |
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C (Holland and Jenkins, 1999, eq.21) |
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dFac = 0. _d 0 |
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IF ( SHELFICEadvDiffHeatFlux ) dFac = 1. _d 0 |
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fwflxFac = 0. _d 0 |
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C linear dependence of freezing point on salinity |
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a0 = -0.0575 _d 0 |
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a1 = 0.0 _d -0 |
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a2 = 0.0 _d -0 |
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c0 = 0.0901 _d 0 |
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b = -7.61 _d -4 |
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#ifdef ALLOW_ISOMIP_TD |
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IF ( useISOMIPTD ) THEN |
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C non-linear dependence of freezing point on salinity |
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a0 = -0.0575 _d 0 |
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a1 = 1.710523 _d -3 |
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a2 = -2.154996 _d -4 |
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b = -7.53 _d -4 |
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c0 = 0. _d 0 |
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ENDIF |
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convertFW2SaltLoc = convertFW2Salt |
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C hardcoding this value here is OK because it only applies to ISOMIP |
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C where this value is part of the protocol |
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IF ( convertFW2SaltLoc .EQ. -1. ) convertFW2SaltLoc = 33.4 _d 0 |
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#endif /* ALLOW_ISOMIP_TD */ |
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|
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DO bj = myByLo(myThid), myByHi(myThid) |
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DO bi = myBxLo(myThid), myBxHi(myThid) |
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DO J = 1-OLy,sNy+OLy |
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DO I = 1-OLx,sNx+OLx |
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shelfIceHeatFlux (I,J,bi,bj) = 0. _d 0 |
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shelfIceFreshWaterFlux(I,J,bi,bj) = 0. _d 0 |
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shelficeForcingT (I,J,bi,bj) = 0. _d 0 |
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shelficeForcingS (I,J,bi,bj) = 0. _d 0 |
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ENDDO |
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ENDDO |
213 |
ENDDO |
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ENDDO |
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#ifdef ALLOW_SHIFWFLX_CONTROL |
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DO bj = myByLo(myThid), myByHi(myThid) |
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DO bi = myBxLo(myThid), myBxHi(myThid) |
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DO J = 1-OLy,sNy+OLy |
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DO I = 1-OLx,sNx+OLx |
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xx_shifwflx_loc(I,J,bi,bj) = 0. _d 0 |
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ENDDO |
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ENDDO |
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ENDDO |
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ENDDO |
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#ifdef ALLOW_CTRL |
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if (useCTRL) CALL CTRL_GET_GEN ( |
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& xx_shifwflx_file, xx_shifwflxstartdate, xx_shifwflxperiod, |
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& maskSHI, xx_shifwflx_loc, xx_shifwflx0, xx_shifwflx1, |
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& xx_shifwflx_dummy, |
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& xx_shifwflx_remo_intercept, xx_shifwflx_remo_slope, |
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& wshifwflx, |
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& myTime, myIter, myThid ) |
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#endif |
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#endif /* ALLOW_SHIFWFLX_CONTROL */ |
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DO bj = myByLo(myThid), myByHi(myThid) |
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DO bi = myBxLo(myThid), myBxHi(myThid) |
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#ifdef ALLOW_AUTODIFF_TAMC |
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# ifdef SHI_ALLOW_GAMMAFRICT |
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act1 = bi - myBxLo(myThid) |
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max1 = myBxHi(myThid) - myBxLo(myThid) + 1 |
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act2 = bj - myByLo(myThid) |
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max2 = myByHi(myThid) - myByLo(myThid) + 1 |
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act3 = myThid - 1 |
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max3 = nTx*nTy |
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act4 = ikey_dynamics - 1 |
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ikey = (act1 + 1) + act2*max1 |
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& + act3*max1*max2 |
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& + act4*max1*max2*max3 |
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# endif /* SHI_ALLOW_GAMMAFRICT */ |
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#endif /* ALLOW_AUTODIFF_TAMC */ |
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DO J = 1, sNy |
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DO I = 1, sNx |
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C-- make local copies of temperature, salinity and depth (pressure in deci-bar) |
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C-- underneath the ice |
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K = MAX(1,kTopC(I,J,bi,bj)) |
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pLoc(I,J) = ABS(R_shelfIce(I,J,bi,bj)) |
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c pLoc(I,J) = shelficeMass(I,J,bi,bj)*gravity*1. _d -4 |
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tLoc(I,J) = theta(I,J,K,bi,bj) |
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sLoc(I,J) = MAX(salt(I,J,K,bi,bj), zeroRL) |
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uLoc(I,J) = recip_hFacC(I,J,K,bi,bj) * |
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& ( uVel(I, J,K,bi,bj) * _hFacW(I, J,K,bi,bj) |
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& + uVel(I+1,J,K,bi,bj) * _hFacW(I+1,J,K,bi,bj) ) |
263 |
vLoc(I,J) = recip_hFacC(I,J,K,bi,bj) * |
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& ( vVel(I,J, K,bi,bj) * _hFacS(I,J, K,bi,bj) |
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& + vVel(I,J+1,K,bi,bj) * _hFacS(I,J+1,K,bi,bj) ) |
266 |
ENDDO |
267 |
ENDDO |
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IF ( SHELFICEBoundaryLayer ) THEN |
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C-- average over boundary layer width |
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DO J = 1, sNy |
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DO I = 1, sNx |
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K = kTopC(I,J,bi,bj) |
273 |
IF ( K .NE. 0 .AND. K .LT. Nr ) THEN |
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Kp1 = MIN(Nr,K+1) |
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C-- overlap into lower cell |
276 |
drKp1 = drF(K)*( 1. _d 0 - _hFacC(I,J,K,bi,bj) ) |
277 |
C-- lower cell may not be as thick as required |
278 |
drKp1 = MIN( drKp1, drF(Kp1) * _hFacC(I,J,Kp1,bi,bj) ) |
279 |
recip_drLoc = 1. _d 0 / |
280 |
& ( drF(K)*_hFacC(I,J,K,bi,bj) + drKp1 ) |
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tLoc(I,J) = ( tLoc(I,J) * drF(K)*_hFacC(I,J,K,bi,bj) |
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& + theta(I,J,Kp1,bi,bj) *drKp1 ) |
283 |
& * recip_drLoc |
284 |
sLoc(I,J) = ( sLoc(I,J) * drF(K)*_hFacC(I,J,K,bi,bj) |
285 |
& + MAX(salt(I,J,Kp1,bi,bj), zeroRL) * drKp1 ) |
286 |
& * recip_drLoc |
287 |
uLoc(I,J) = ( uLoc(I,J) * drF(K)*_hFacC(I,J,K,bi,bj) |
288 |
& + drKp1 * recip_hFacC(I,J,Kp1,bi,bj) * |
289 |
& ( uVel(I, J,Kp1,bi,bj) * _hFacW(I, J,Kp1,bi,bj) |
290 |
& + uVel(I+1,J,Kp1,bi,bj) * _hFacW(I+1,J,Kp1,bi,bj) ) |
291 |
& ) * recip_drLoc |
292 |
vLoc(I,J) = ( vLoc(I,J) * drF(K)*_hFacC(I,J,K,bi,bj) |
293 |
& + drKp1 * recip_hFacC(I,J,Kp1,bi,bj) * |
294 |
& ( vVel(I,J, Kp1,bi,bj) * _hFacS(I,J, Kp1,bi,bj) |
295 |
& + vVel(I,J+1,Kp1,bi,bj) * _hFacS(I,J+1,Kp1,bi,bj) ) |
296 |
& ) * recip_drLoc |
297 |
ENDIF |
298 |
ENDDO |
299 |
ENDDO |
300 |
ENDIF |
301 |
|
302 |
C-- turn potential temperature into in-situ temperature relative |
303 |
C-- to the surface |
304 |
DO J = 1, sNy |
305 |
DO I = 1, sNx |
306 |
#ifndef ALLOW_OPENAD |
307 |
tLoc(I,J) = SW_TEMP(sLoc(I,J),tLoc(I,J),pLoc(I,J),zeroRL) |
308 |
#else |
309 |
CALL SW_TEMP(sLoc(I,J),tLoc(I,J),pLoc(I,J),zeroRL,tLoc(I,J)) |
310 |
#endif |
311 |
ENDDO |
312 |
ENDDO |
313 |
|
314 |
#ifdef SHI_ALLOW_GAMMAFRICT |
315 |
IF ( SHELFICEuseGammaFrict ) THEN |
316 |
DO J = 1, sNy |
317 |
DO I = 1, sNx |
318 |
K = kTopC(I,J,bi,bj) |
319 |
IF ( K .NE. 0 .AND. pLoc(I,J) .GT. 0. _d 0 ) THEN |
320 |
ustarSq = shiCdrag * MAX( 1.D-6, |
321 |
& 0.25 _d 0 *(uLoc(I,J)*uLoc(I,J)+vLoc(I,J)*vLoc(I,J)) ) |
322 |
ustar = SQRT(ustarSq) |
323 |
C instead of etastar = sqrt(1+zetaN*ustar./(f*Lo*Rc)) |
324 |
C etastar = 1. _d 0 |
325 |
C gammaTurbConst = 1. _d 0 / (2. _d 0 * shiZetaN*etastar) |
326 |
C & - recip_shiKarman |
327 |
IF ( fCori(I,J,bi,bj) .NE. 0. _d 0 ) THEN |
328 |
gammaTurb = LOG( ustarSq * shiZetaN * etastar**2 |
329 |
& / ABS(fCori(I,J,bi,bj) * 5.0 _d 0 * shiKinVisc)) |
330 |
& * recip_shiKarman |
331 |
& + gammaTurbConst |
332 |
C Do we need to catch the unlikely case of very small ustar |
333 |
C that can lead to negative gammaTurb? |
334 |
C gammaTurb = MAX(0.D0, gammaTurb) |
335 |
ELSE |
336 |
gammaTurb = gammaTurbConst |
337 |
ENDIF |
338 |
shiTransCoeffT(i,j,bi,bj) = MAX( zeroRL, |
339 |
& ustar/(gammaTurb + gammaTmoleT) ) |
340 |
shiTransCoeffS(i,j,bi,bj) = MAX( zeroRL, |
341 |
& ustar/(gammaTurb + gammaTmoleS) ) |
342 |
ENDIF |
343 |
ENDDO |
344 |
ENDDO |
345 |
ENDIF |
346 |
#endif /* SHI_ALLOW_GAMMAFRICT */ |
347 |
|
348 |
#ifdef ALLOW_AUTODIFF_TAMC |
349 |
# ifdef SHI_ALLOW_GAMMAFRICT |
350 |
CADJ STORE shiTransCoeffS(:,:,bi,bj) = comlev1_bibj, |
351 |
CADJ & key=ikey, byte=isbyte |
352 |
CADJ STORE shiTransCoeffT(:,:,bi,bj) = comlev1_bibj, |
353 |
CADJ & key=ikey, byte=isbyte |
354 |
# endif /* SHI_ALLOW_GAMMAFRICT */ |
355 |
#endif /* ALLOW_AUTODIFF_TAMC */ |
356 |
#ifdef ALLOW_ISOMIP_TD |
357 |
IF ( useISOMIPTD ) THEN |
358 |
DO J = 1, sNy |
359 |
DO I = 1, sNx |
360 |
K = kTopC(I,J,bi,bj) |
361 |
IF ( K .NE. 0 .AND. pLoc(I,J) .GT. 0. _d 0 ) THEN |
362 |
C-- Calculate freezing temperature as a function of salinity and pressure |
363 |
thetaFreeze = |
364 |
& sLoc(I,J) * ( a0 + a1*sqrt(sLoc(I,J)) + a2*sLoc(I,J) ) |
365 |
& + b*pLoc(I,J) + c0 |
366 |
C-- Calculate the upward heat and fresh water fluxes |
367 |
shelfIceHeatFlux(I,J,bi,bj) = maskC(I,J,K,bi,bj) |
368 |
& * shiTransCoeffT(i,j,bi,bj) |
369 |
& * ( tLoc(I,J) - thetaFreeze ) |
370 |
& * HeatCapacity_Cp*rUnit2mass |
371 |
#ifdef ALLOW_SHIFWFLX_CONTROL |
372 |
& - xx_shifwflx_loc(I,J,bi,bj)*SHELFICElatentHeat |
373 |
#endif /* ALLOW_SHIFWFLX_CONTROL */ |
374 |
C upward heat flux into the shelf-ice implies basal melting, |
375 |
C thus a downward (negative upward) fresh water flux (as a mass flux), |
376 |
C and vice versa |
377 |
shelfIceFreshWaterFlux(I,J,bi,bj) = |
378 |
& - shelfIceHeatFlux(I,J,bi,bj) |
379 |
& *recip_SHELFICElatentHeat |
380 |
C-- compute surface tendencies |
381 |
shelficeForcingT(i,j,bi,bj) = |
382 |
& - shelfIceHeatFlux(I,J,bi,bj) |
383 |
& *recip_Cp*mass2rUnit |
384 |
& - cFac * shelfIceFreshWaterFlux(I,J,bi,bj)*mass2rUnit |
385 |
& * ( thetaFreeze - tLoc(I,J) ) |
386 |
shelficeForcingS(i,j,bi,bj) = |
387 |
& shelfIceFreshWaterFlux(I,J,bi,bj) * mass2rUnit |
388 |
& * ( cFac*sLoc(I,J) + (1. _d 0-cFac)*convertFW2SaltLoc ) |
389 |
C-- stress at the ice/water interface is computed in separate |
390 |
C routines that are called from mom_fluxform/mom_vecinv |
391 |
ELSE |
392 |
shelfIceHeatFlux (I,J,bi,bj) = 0. _d 0 |
393 |
shelfIceFreshWaterFlux(I,J,bi,bj) = 0. _d 0 |
394 |
shelficeForcingT (I,J,bi,bj) = 0. _d 0 |
395 |
shelficeForcingS (I,J,bi,bj) = 0. _d 0 |
396 |
ENDIF |
397 |
ENDDO |
398 |
ENDDO |
399 |
ELSE |
400 |
#else |
401 |
IF ( .TRUE. ) THEN |
402 |
#endif /* ALLOW_ISOMIP_TD */ |
403 |
C use BRIOS thermodynamics, following Hellmers PhD thesis: |
404 |
C Hellmer, H., 1989, A two-dimensional model for the thermohaline |
405 |
C circulation under an ice shelf, Reports on Polar Research, No. 60 |
406 |
C (in German). |
407 |
|
408 |
DO J = 1, sNy |
409 |
DO I = 1, sNx |
410 |
K = kTopC(I,J,bi,bj) |
411 |
IF ( K .NE. 0 .AND. pLoc(I,J) .GT. 0. _d 0 ) THEN |
412 |
C heat flux into the ice shelf, default is diffusive flux |
413 |
C (Holland and Jenkins, 1999, eq.21) |
414 |
thetaFreeze = a0*sLoc(I,J)+c0+b*pLoc(I,J) |
415 |
fwflxFac = 0. _d 0 |
416 |
IF ( tLoc(I,J) .GT. thetaFreeze ) fwflxFac = dFac |
417 |
C a few abbreviations |
418 |
eps1 = rUnit2mass*HeatCapacity_Cp |
419 |
& *shiTransCoeffT(i,j,bi,bj) |
420 |
eps2 = rUnit2mass*SHELFICElatentHeat |
421 |
& *shiTransCoeffS(i,j,bi,bj) |
422 |
eps5 = rUnit2mass*HeatCapacity_Cp |
423 |
& *shiTransCoeffS(i,j,bi,bj) |
424 |
|
425 |
C solve quadratic equation for salinity at shelfice-ocean interface |
426 |
C note: this part of the code is not very intuitive as it involves |
427 |
C many arbitrary abbreviations that were introduced to derive the |
428 |
C correct form of the quadratic equation for salinity. The abbreviations |
429 |
C only make sense in connection with my notes on this (M.Losch) |
430 |
C |
431 |
C eps3a was introduced as a constant variant of eps3 to avoid AD of |
432 |
C code of typ (pLoc-const)/pLoc |
433 |
eps3a = rhoShelfIce*SHELFICEheatCapacity_Cp |
434 |
& * SHELFICEkappa * ( 1. _d 0 - dFac ) |
435 |
eps3 = eps3a/pLoc(I,J) |
436 |
eps4 = b*pLoc(I,J) + c0 |
437 |
eps6 = eps4 - tLoc(I,J) |
438 |
eps7 = eps4 - SHELFICEthetaSurface |
439 |
eps8 = rUnit2mass*SHELFICEheatCapacity_Cp |
440 |
& *shiTransCoeffS(i,j,bi,bj) * fwflxFac |
441 |
aqe = a0 *(eps1+eps3-eps8) |
442 |
recip_aqe = 0. _d 0 |
443 |
IF ( aqe .NE. 0. _d 0 ) recip_aqe = 0.5 _d 0/aqe |
444 |
c bqe = eps1*eps6 + eps3*eps7 - eps2 |
445 |
bqe = eps1*eps6 |
446 |
& + eps3a*( b |
447 |
& + ( c0 - SHELFICEthetaSurface )/pLoc(I,J) ) |
448 |
& - eps2 |
449 |
& + eps8*( a0*sLoc(I,J) - eps7 ) |
450 |
cqe = ( eps2 + eps8*eps7 )*sLoc(I,J) |
451 |
discrim = bqe*bqe - 4. _d 0*aqe*cqe |
452 |
#undef ALLOW_SHELFICE_DEBUG |
453 |
#ifdef ALLOW_SHELFICE_DEBUG |
454 |
IF ( discrim .LT. 0. _d 0 ) THEN |
455 |
print *, 'ml-shelfice: discrim = ', discrim,aqe,bqe,cqe |
456 |
print *, 'ml-shelfice: pLoc = ', pLoc(I,J) |
457 |
print *, 'ml-shelfice: tLoc = ', tLoc(I,J) |
458 |
print *, 'ml-shelfice: sLoc = ', sLoc(I,J) |
459 |
print *, 'ml-shelfice: tsurface= ', |
460 |
& SHELFICEthetaSurface |
461 |
print *, 'ml-shelfice: eps1 = ', eps1 |
462 |
print *, 'ml-shelfice: eps2 = ', eps2 |
463 |
print *, 'ml-shelfice: eps3 = ', eps3 |
464 |
print *, 'ml-shelfice: eps4 = ', eps4 |
465 |
print *, 'ml-shelfice: eps5 = ', eps5 |
466 |
print *, 'ml-shelfice: eps6 = ', eps6 |
467 |
print *, 'ml-shelfice: eps7 = ', eps7 |
468 |
print *, 'ml-shelfice: eps8 = ', eps8 |
469 |
print *, 'ml-shelfice: rU2mass = ', rUnit2mass |
470 |
print *, 'ml-shelfice: rhoIce = ', rhoShelfIce |
471 |
print *, 'ml-shelfice: cFac = ', cFac |
472 |
print *, 'ml-shelfice: Cp_W = ', HeatCapacity_Cp |
473 |
print *, 'ml-shelfice: Cp_I = ', |
474 |
& SHELFICEHeatCapacity_Cp |
475 |
print *, 'ml-shelfice: gammaT = ', |
476 |
& SHELFICEheatTransCoeff |
477 |
print *, 'ml-shelfice: gammaS = ', |
478 |
& SHELFICEsaltTransCoeff |
479 |
print *, 'ml-shelfice: lat.heat= ', |
480 |
& SHELFICElatentHeat |
481 |
STOP 'ABNORMAL END in S/R SHELFICE_THERMODYNAMICS' |
482 |
ENDIF |
483 |
#endif /* ALLOW_SHELFICE_DEBUG */ |
484 |
saltFreeze = (- bqe - SQRT(discrim))*recip_aqe |
485 |
IF ( saltFreeze .LT. 0. _d 0 ) |
486 |
& saltFreeze = (- bqe + SQRT(discrim))*recip_aqe |
487 |
thetaFreeze = a0*saltFreeze + eps4 |
488 |
C-- upward fresh water flux due to melting (in kg/m^2/s) |
489 |
cph change to identical form |
490 |
cph freshWaterFlux = rUnit2mass |
491 |
cph & * shiTransCoeffS(i,j,bi,bj) |
492 |
cph & * ( saltFreeze - sLoc(I,J) ) / saltFreeze |
493 |
freshWaterFlux = rUnit2mass |
494 |
& * shiTransCoeffS(i,j,bi,bj) |
495 |
& * ( 1. _d 0 - sLoc(I,J) / saltFreeze ) |
496 |
#ifdef ALLOW_SHIFWFLX_CONTROL |
497 |
& + xx_shifwflx_loc(I,J,bi,bj) |
498 |
#endif /* ALLOW_SHIFWFLX_CONTROL */ |
499 |
C-- Calculate the upward heat and fresh water fluxes; |
500 |
C-- MITgcm sign conventions: downward (negative) fresh water flux |
501 |
C-- implies melting and due to upward (positive) heat flux |
502 |
shelfIceHeatFlux(I,J,bi,bj) = |
503 |
& ( eps3 |
504 |
& - freshWaterFlux*SHELFICEheatCapacity_Cp*fwflxFac ) |
505 |
& * ( thetaFreeze - SHELFICEthetaSurface ) |
506 |
& - cFac*freshWaterFlux*( SHELFICElatentHeat |
507 |
& - HeatCapacity_Cp*( thetaFreeze - rFac*tLoc(I,J) ) ) |
508 |
shelfIceFreshWaterFlux(I,J,bi,bj) = freshWaterFlux |
509 |
C-- compute surface tendencies |
510 |
shelficeForcingT(i,j,bi,bj) = |
511 |
& ( shiTransCoeffT(i,j,bi,bj) |
512 |
& - cFac*shelfIceFreshWaterFlux(I,J,bi,bj)*mass2rUnit ) |
513 |
& * ( thetaFreeze - tLoc(I,J) ) |
514 |
shelficeForcingS(i,j,bi,bj) = |
515 |
& ( shiTransCoeffS(i,j,bi,bj) |
516 |
& - cFac*shelfIceFreshWaterFlux(I,J,bi,bj)*mass2rUnit ) |
517 |
& * ( saltFreeze - sLoc(I,J) ) |
518 |
ELSE |
519 |
shelfIceHeatFlux (I,J,bi,bj) = 0. _d 0 |
520 |
shelfIceFreshWaterFlux(I,J,bi,bj) = 0. _d 0 |
521 |
shelficeForcingT (I,J,bi,bj) = 0. _d 0 |
522 |
shelficeForcingS (I,J,bi,bj) = 0. _d 0 |
523 |
ENDIF |
524 |
ENDDO |
525 |
ENDDO |
526 |
ENDIF |
527 |
C endif (not) useISOMIPTD |
528 |
ENDDO |
529 |
ENDDO |
530 |
|
531 |
IF (SHELFICEallowThinIceMass) then |
532 |
#ifdef ALLOW_STREAMICE |
533 |
DO bj = myByLo(myThid), myByHi(myThid) |
534 |
DO bi = myBxLo(myThid), myBxHi(myThid) |
535 |
DO j=1-Oly,sNy+Oly-1 |
536 |
DO i=1-Olx+1,sNx+Olx-1 |
537 |
|
538 |
if (streamice_hmask(i,j,bi,bj).eq.1 .or. |
539 |
& streamice_hmask(i,j,bi,bj).eq.2) then |
540 |
|
541 |
shelficeMass(i,j,bi,bj) = |
542 |
& H_streamice(I,J,bi,bj) * streamice_density |
543 |
|
544 |
endif |
545 |
|
546 |
ENDDO |
547 |
ENDDO |
548 |
ENDDO |
549 |
ENDDO |
550 |
#else |
551 |
CALL SHELFICE_STEP_ICEMASS( myTime, myIter, myThid ) |
552 |
#endif |
553 |
ENDIF |
554 |
|
555 |
C-- Calculate new loading anomaly (in case the ice-shelf mass was updated) |
556 |
#ifndef ALLOW_AUTODIFF |
557 |
c IF ( SHELFICEloadAnomalyFile .EQ. ' ' ) THEN |
558 |
DO bj = myByLo(myThid), myByHi(myThid) |
559 |
DO bi = myBxLo(myThid), myBxHi(myThid) |
560 |
DO j = 1-OLy, sNy+OLy |
561 |
DO i = 1-OLx, sNx+OLx |
562 |
shelficeLoadAnomaly(i,j,bi,bj) = gravity |
563 |
& *( shelficeMass(i,j,bi,bj) + rhoConst*Ro_surf(i,j,bi,bj) ) |
564 |
ENDDO |
565 |
ENDDO |
566 |
ENDDO |
567 |
ENDDO |
568 |
c ENDIF |
569 |
#endif /* ndef ALLOW_AUTODIFF */ |
570 |
|
571 |
#ifdef ALLOW_DIAGNOSTICS |
572 |
IF ( useDiagnostics ) THEN |
573 |
CALL DIAGNOSTICS_FILL_RS(shelfIceFreshWaterFlux,'SHIfwFlx', |
574 |
& 0,1,0,1,1,myThid) |
575 |
CALL DIAGNOSTICS_FILL_RS(shelfIceHeatFlux, 'SHIhtFlx', |
576 |
& 0,1,0,1,1,myThid) |
577 |
C SHIForcT (Ice shelf forcing for theta [W/m2], >0 increases theta) |
578 |
tmpFac = HeatCapacity_Cp*rUnit2mass |
579 |
CALL DIAGNOSTICS_SCALE_FILL(shelficeForcingT,tmpFac,1, |
580 |
& 'SHIForcT',0,1,0,1,1,myThid) |
581 |
C SHIForcS (Ice shelf forcing for salt [g/m2/s], >0 increases salt) |
582 |
tmpFac = rUnit2mass |
583 |
CALL DIAGNOSTICS_SCALE_FILL(shelficeForcingS,tmpFac,1, |
584 |
& 'SHIForcS',0,1,0,1,1,myThid) |
585 |
C Transfer coefficients |
586 |
CALL DIAGNOSTICS_FILL(shiTransCoeffT,'SHIgammT', |
587 |
& 0,1,0,1,1,myThid) |
588 |
CALL DIAGNOSTICS_FILL(shiTransCoeffS,'SHIgammS', |
589 |
& 0,1,0,1,1,myThid) |
590 |
ENDIF |
591 |
#endif /* ALLOW_DIAGNOSTICS */ |
592 |
|
593 |
#endif /* ALLOW_SHELFICE */ |
594 |
RETURN |
595 |
END |