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C $Header: /u/gcmpack/MITgcm/pkg/seaice/seaice_evp.F,v 1.47 2013/01/04 14:33:56 mlosch Exp $ |
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C $Name: $ |
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|
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#include "SEAICE_OPTIONS.h" |
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#ifdef ALLOW_OBCS |
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# include "OBCS_OPTIONS.h" |
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#else |
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# define OBCS_UVICE_OLD |
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#endif |
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|
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CBOP |
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C !ROUTINE: SEAICE_EVP |
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C !INTERFACE: |
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SUBROUTINE SEAICE_EVP( myTime, myIter, myThid ) |
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|
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C !DESCRIPTION: \bv |
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C *==========================================================* |
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C | SUBROUTINE SEAICE_EVP |
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C | o Ice dynamics using an EVP solver following |
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C | E. C. Hunke and J. K. Dukowicz. An |
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C | Elastic-Viscous-Plastic Model for Sea Ice Dynamics, |
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C | J. Phys. Oceanogr., 27, 1849-1867 (1997). |
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C *==========================================================* |
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C | written by Martin Losch, March 2006 |
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C *==========================================================* |
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C \ev |
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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 "DYNVARS.h" |
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#include "GRID.h" |
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#include "SEAICE_SIZE.h" |
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#include "SEAICE_PARAMS.h" |
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#include "SEAICE.h" |
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|
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#ifdef ALLOW_AUTODIFF_TAMC |
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# include "tamc.h" |
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#endif |
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|
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C !INPUT/OUTPUT PARAMETERS: |
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C === Routine arguments === |
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C myTime :: Simulation time |
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C myIter :: Simulation timestep number |
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C myThid :: my Thread Id. number |
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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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#if ( defined (SEAICE_CGRID) && \ |
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defined (SEAICE_ALLOW_EVP) && \ |
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defined (SEAICE_ALLOW_DYNAMICS) ) |
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|
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C === Local variables === |
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C i,j,bi,bj :: Loop counters |
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C kSrf :: vertical index of surface layer |
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C nEVPstep :: number of timesteps within the EVP solver |
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C iEVPstep :: Loop counter |
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C SIN/COSWAT :: sine/cosine of turning angle |
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C (recip_)ecc2 :: (one over) eccentricity squared |
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C recip_evpAlpha :: 1/SEAICE_evpAlpha |
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C recip_deltaT :: 1/SEAICE_deltaTdyn |
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C evpStarFac :: 1 if SEAICEuseEVPstar = .true., 0 otherwise |
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C betaFac :: SEAICE_evpBeta/SEAICE_deltaTdyn=1/SEAICE_deltaTevp |
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C betaFacP1 :: betaFac + evpStarFac/SEAICE_deltaTdyn |
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C e11,e12,e22 :: components of strain rate tensor |
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C seaice_div :: divergence strain rates at C-points times P |
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C /divided by Delta minus 1 |
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C seaice_tension :: tension strain rates at C-points times P |
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C /divided by Delta |
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C seaice_shear :: shear strain rates, defined at Z-points times P |
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C /divided by Delta |
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C sig11, sig22 :: sum and difference of diagonal terms of stress tensor |
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|
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INTEGER i, j, bi, bj |
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INTEGER kSrf |
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INTEGER nEVPstep, iEVPstep |
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#ifdef ALLOW_AUTODIFF_TAMC |
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INTEGER ikeyloc |
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#else |
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INTEGER nEVPstepMax |
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#endif |
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|
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_RL COSWAT |
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_RS SINWAT |
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_RL ecc2, recip_ecc2, recip_evpAlpha, recip_deltaT |
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_RL betaFacP1, betaFac, evpStarFac |
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|
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_RL seaice_div (1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RL seaice_tension(1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RL seaice_shear (1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RL sig11 (1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RL sig22 (1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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C auxilliary variables |
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_RL ep (1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RL em (1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RL pressC (1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RL zetaC (1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RL deltaZ (1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RL zetaZ (1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RL deltaC (1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RL deltaCreg, deltaZreg, pressZ |
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#ifdef SEAICE_ALLOW_TEM |
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_RL etaDenC, zetaMaxC, etaDenZ, zetaMaxZ |
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#endif /* SEAICE_ALLOW_TEM */ |
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#ifdef SEAICE_ALLOW_CLIPZETA |
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_RL zMaxZ, zMinZ, fac |
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#endif /* SEAICE_ALLOW_CLIPZETA */ |
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_RL denom1, denom2, facZ |
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_RL locMaskU, locMaskV |
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|
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C surface level |
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kSrf = 1 |
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C-- introduce turning angles |
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SINWAT=SIN(SEAICE_waterTurnAngle*deg2rad) |
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COSWAT=COS(SEAICE_waterTurnAngle*deg2rad) |
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|
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C abbreviation eccentricity squared |
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ecc2=SEAICE_eccen**2 |
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recip_ecc2 = 0. _d 0 |
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IF ( ecc2 .NE. 0. _d 0 ) recip_ecc2=ONE/ecc2 |
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C determine number of internal time steps |
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nEVPstep = INT(SEAICE_deltaTdyn/SEAICE_deltaTevp) |
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IF ( SEAICEnEVPstarSteps.NE.UNSET_I ) nEVPstep=SEAICEnEVPstarSteps |
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C SEAICE_evpAlpha = 2. * SEAICE_evpTauRelax/SEAICE_deltaTevp |
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denom1 = SEAICE_evpAlpha / ( SEAICE_evpAlpha + 1. _d 0 ) |
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denom2 = SEAICE_evpAlpha / ( SEAICE_evpAlpha + ecc2 ) |
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|
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recip_deltaT = 1. _d 0 / SEAICE_deltaTdyn |
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recip_evpAlpha = 0. _d 0 |
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IF ( SEAICE_evpAlpha .GT. 0. _d 0 ) |
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& recip_evpAlpha = 1. _d 0 / SEAICE_evpAlpha |
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evpStarFac = 0. _d 0 |
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IF ( SEAICEuseEVPstar ) evpStarFac = 1. _d 0 |
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|
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betaFac = SEAICE_evpBeta*recip_deltaT |
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betaFacP1 = betaFac + evpStarFac*recip_deltaT |
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#ifndef ALLOW_AUTODIFF_TAMC |
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nEVPstepMax = nEVPstep |
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#endif |
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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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C use u/vIce as work arrays: copy previous time step to u/vIceNm1 |
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uIceNm1(I,J,bi,bj) = uIce(I,J,bi,bj) |
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vIceNm1(I,J,bi,bj) = vIce(I,J,bi,bj) |
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C initialise strain rates |
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e11 (I,J,bi,bj) = 0. _d 0 |
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e22 (I,J,bi,bj) = 0. _d 0 |
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e12 (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 SEAICE_ALLOW_CLIPZETA |
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C damping constraint (Hunke, J.Comp.Phys.,2001) |
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IF ( SEAICE_evpDampC .GT. 0. _d 0 ) THEN |
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CML fac = HALF * SEAICE_evpDampC * SEAICE_evpTauRelax |
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CML & /SEAICE_deltaTevp**2 |
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fac = 0.25 _d 0 * SEAICE_evpDampC * SEAICE_evpAlpha |
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& /SEAICE_deltaTevp |
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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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zMax (I,J,bi,bj) = _rA(I,J,bi,bj) * fac |
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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 |
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#endif /* SEAICE_ALLOW_CLIPZETA */ |
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C |
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C start of the main time loop |
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DO iEVPstep = 1, nEVPstepMax |
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IF (iEVPstep.LE.nEVPstep) THEN |
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C |
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#ifdef ALLOW_AUTODIFF_TAMC |
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ikeyloc = iEVPstep + |
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& (ikey_dynamics-1)*nEVPstepMax |
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CADJ STORE uice = comlev1_evp, |
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CADJ & key = ikeyloc, byte = isbyte |
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CADJ STORE vice = comlev1_evp, |
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CADJ & key = ikeyloc, byte = isbyte |
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CADJ STORE seaice_sigma1 = comlev1_evp, |
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CADJ & key = ikeyloc, byte = isbyte |
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CADJ STORE seaice_sigma2 = comlev1_evp, |
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CADJ & key = ikeyloc, byte = isbyte |
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CADJ STORE seaice_sigma12 = comlev1_evp, |
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CADJ & key = ikeyloc, byte = isbyte |
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#endif /* ALLOW_AUTODIFF_TAMC */ |
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C |
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C first calculate strain rates and bulk moduli/viscosities |
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C |
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CALL SEAICE_CALC_STRAINRATES( |
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I uIce, vIce, |
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O e11, e22, e12, |
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I iEVPstep, myTime, myIter, myThid ) |
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|
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#ifdef ALLOW_AUTODIFF_TAMC |
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CADJ STORE e11 = comlev1_evp,key = ikeyloc, byte = isbyte |
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CADJ STORE e12 = comlev1_evp,key = ikeyloc, byte = isbyte |
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CADJ STORE e22 = comlev1_evp,key = ikeyloc, byte = isbyte |
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#endif /* ALLOW_AUTODIFF_TAMC */ |
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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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seaice_div (I,J) = 0. _d 0 |
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seaice_tension(I,J) = 0. _d 0 |
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seaice_shear (I,J) = 0. _d 0 |
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pressC (I,J) = 0. _d 0 |
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zetaC (I,J) = 0. _d 0 |
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deltaZ (I,J) = 0. _d 0 |
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zetaZ (I,J) = 0. _d 0 |
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deltaC (I,J) = 0. _d 0 |
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ENDDO |
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ENDDO |
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DO j=1-OLy,sNy+OLy |
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DO i=1-OLx,sNx+OLx |
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ep(i,j) = e11(i,j,bi,bj) + e22(i,j,bi,bj) |
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em(i,j) = e11(i,j,bi,bj) - e22(i,j,bi,bj) |
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ENDDO |
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ENDDO |
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DO j=0,sNy+1 |
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DO i=0,sNx+1 |
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C average strain rates to Z and C points |
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facZ = 0.25 _d 0 |
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CML facZ = 1.0 _d 0 |
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CML & / MAX(1.D0,maskC(I, J, kSrf,bi,bj) |
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CML & + maskC(I-1,J, kSrf,bi,bj) |
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CML & + maskC(I, J-1,kSrf,bi,bj) |
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CML & + maskC(I-1,J-1,kSrf,bi,bj) ) |
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C Averaging the squares gives more accurate viscous-plastic behavior |
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C than squaring the averages |
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deltaC(I,J) = |
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& ep(I,J)**2 + recip_ecc2*em(I,J)**2 |
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& + recip_ecc2* |
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& ( e12(I, J,bi,bj)**2 + e12(I+1,J+1,bi,bj)**2 |
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& + e12(I+1,J,bi,bj)**2 + e12(I, J+1,bi,bj)**2 ) |
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deltaZ(I,J) = facZ * |
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& ( ep(I,J )**2 + ep(I-1,J )**2 |
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& + ep(I,J-1)**2 + ep(I-1,J-1)**2 |
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& +(em(I,J )**2 + em(I-1,J )**2 |
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& +em(I,J-1)**2 + em(I-1,J-1)**2)*recip_ecc2 |
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& ) |
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& + 4. _d 0*recip_ecc2*e12(I,J,bi,bj)**2 |
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#ifdef ALLOW_AUTODIFF_TAMC |
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C avoid sqrt of 0 |
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IF ( deltaC(I,J) .GT. 0. _d 0 ) |
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& deltaC(I,J) = SQRT(deltaC(I,J)) |
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IF ( deltaZ(I,J) .GT. 0. _d 0 ) |
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& deltaZ(I,J) = SQRT(deltaZ(I,J)) |
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#else |
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deltaC(I,J) = SQRT(deltaC(I,J)) |
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deltaZ(I,J) = SQRT(deltaZ(I,J)) |
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#endif /* ALLOW_AUTODIFF_TAMC */ |
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deltaCreg = MAX(deltaC(I,J),SEAICE_EPS) |
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deltaZreg = MAX(deltaZ(I,J),SEAICE_EPS) |
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C modify pressure (copied from seaice_calc_viscosities) |
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zetaC(I,J) = HALF*press0(I,J,bi,bj)/deltaCreg |
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pressZ = (deltaZ(I,J)/deltaZreg) * facZ |
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& * ( PRESS0(I,J ,bi,bj) + PRESS0(I-1,J ,bi,bj) |
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& + PRESS0(I,J-1,bi,bj) + PRESS0(I-1,J-1,bi,bj) ) |
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zetaZ(I,J) = HALF/deltaZreg * pressZ |
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ENDDO |
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ENDDO |
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#ifdef SEAICE_ALLOW_CLIPZETA |
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#ifdef ALLOW_AUTODIFF_TAMC |
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CADJ STORE zetac = comlev1_evp,key = ikeyloc, byte = isbyte |
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CADJ STORE zetaz = comlev1_evp,key = ikeyloc, byte = isbyte |
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#endif /* ALLOW_AUTODIFF_TAMC */ |
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C regularize zeta if necessary |
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DO j=0,sNy+1 |
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DO i=0,sNx+1 |
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zetaC(I,J) = MAX(zMin(I,J,bi,bj),MIN(zMax(I,J,bi,bj) |
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& ,zetaC(I,J))) |
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CML zetaC(I,J) = zetaC(I,J)*hEffM(I,J,bi,bj) |
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C |
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C zMin, zMax are defined at C-points, make sure that they are not |
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C masked by boundaries/land points |
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zMaxZ = MAX( |
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& MAX(zMax(I, J,bi,bj),zMax(I, J-1,bi,bj)), |
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& MAX(zMax(I-1,J,bi,bj),zMax(I-1,J-1,bi,bj)) ) |
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zMinZ = MAX( |
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& MAX(zMin(I, J,bi,bj),zMin(I, J-1,bi,bj)), |
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& MAX(zMin(I-1,J,bi,bj),zMin(I-1,J-1,bi,bj)) ) |
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zetaZ(I,J) = MAX(zMinZ,MIN(zMaxZ,zetaZ(I,J))) |
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ENDDO |
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ENDDO |
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#endif /* SEAICE_ALLOW_CLIPZETA */ |
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C recompute pressure |
| 301 |
DO j=0,sNy+1 |
| 302 |
DO i=0,sNx+1 |
| 303 |
pressC(I,J) = TWO*zetaC(I,J)*deltaC(I,J) |
| 304 |
ENDDO |
| 305 |
ENDDO |
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#ifdef ALLOW_DIAGNOSTICS |
| 307 |
IF ( useDiagnostics ) THEN |
| 308 |
C save eta, zeta, and pressure for diagnostics |
| 309 |
DO j=1,sNy |
| 310 |
DO i=1,sNx |
| 311 |
press(I,J,bi,bj) = pressC(I,J) |
| 312 |
zeta (I,J,bi,bj) = zetaC(I,J) |
| 313 |
eta (I,J,bi,bj) = zetaC(I,J)*recip_ecc2 |
| 314 |
ENDDO |
| 315 |
ENDDO |
| 316 |
ENDIF |
| 317 |
#endif /* ALLOW_DIAGNOSTICS */ |
| 318 |
C Calculate the RHS of the stress equations. Do this now in order to |
| 319 |
C avoid multiple divisions by Delta |
| 320 |
C P * ( D_d/Delta - 1 ) = 2*zeta*D_d - P = 2*zeta*D_d - 2*zeta*Delta |
| 321 |
C P * ( D_t/Delta ) = 2*zeta*D_t |
| 322 |
C P * ( D_s/Delta ) = 2*zeta*D_s |
| 323 |
#ifdef SEAICE_ALLOW_TEM |
| 324 |
IF ( SEAICEuseTEM ) THEN |
| 325 |
DO j=0,sNy+1 |
| 326 |
DO i=0,sNx+1 |
| 327 |
facZ = 0.25 _d 0 |
| 328 |
CML facZ = 1.0 _d 0 |
| 329 |
CML & / MAX(1.D0,maskC(I, J, kSrf,bi,bj) |
| 330 |
CML & + maskC(I-1,J, kSrf,bi,bj) |
| 331 |
CML & + maskC(I, J-1,kSrf,bi,bj) |
| 332 |
CML & + maskC(I-1,J-1,kSrf,bi,bj) ) |
| 333 |
C Averaging the squares gives more accurate viscous-plastic behavior |
| 334 |
C than squaring the averages |
| 335 |
etaDenC = em(I,J)**2 + |
| 336 |
& ( e12(I, J,bi,bj)**2 + e12(I+1,J+1,bi,bj)**2 |
| 337 |
& + e12(I+1,J,bi,bj)**2 + e12(I, J+1,bi,bj)**2 ) |
| 338 |
etaDenC = SQRT(MAX(SEAICE_EPS_SQ,etaDenC)) |
| 339 |
zetaMaxC = ecc2*zetaC(I,J)*(deltaC(I,J)-ep(I,J))/etaDenC |
| 340 |
etaDenZ = |
| 341 |
& facZ * ( em(I, J )**2 + em(I-1,J-1)**2 |
| 342 |
& + em(I-1,J )**2 + em(I, J-1)**2 ) |
| 343 |
& + 4. _d 0*e12(I,J,bi,bj)**2 |
| 344 |
etaDenZ = SQRT(MAX(SEAICE_EPS_SQ,etaDenZ)) |
| 345 |
zetaMaxZ = ecc2*zetaZ(I,J) * ( deltaZ(I,J) |
| 346 |
& - facZ * ( ep(I,J ) + ep(I-1,J ) |
| 347 |
& + ep(I,J-1) + ep(I-1,J-1) ) |
| 348 |
& )/etaDenZ |
| 349 |
#ifdef ALLOW_DIAGNOSTICS |
| 350 |
C save new eta for diagnostics |
| 351 |
eta(I,J,bi,bj) = MIN(zetaC(I,J),zetaMaxC)*recip_ecc2 |
| 352 |
#endif /* ALLOW_DIAGNOSTICS */ |
| 353 |
seaice_div (I,J) = |
| 354 |
& ( 2. _d 0 *zetaC(I,J)*ep(I,J) - pressC(I,J) |
| 355 |
& ) * hEffM(I,J,bi,bj) |
| 356 |
seaice_tension(I,J) = 2. _d 0*MIN(zetaC(I,J),zetaMaxC) |
| 357 |
& * em(I,J) * hEffM(I,J,bi,bj) |
| 358 |
seaice_shear (I,J) = 2. _d 0*MIN(zetaZ(I,J),zetaMaxZ) |
| 359 |
& * 2. _d 0*e12(I,J,bi,bj) |
| 360 |
ENDDO |
| 361 |
ENDDO |
| 362 |
ELSE |
| 363 |
#else |
| 364 |
IF (.TRUE. ) THEN |
| 365 |
#endif /* SEAICE_ALLOW_TEM */ |
| 366 |
DO j=0,sNy+1 |
| 367 |
DO i=0,sNx+1 |
| 368 |
seaice_div (I,J) = |
| 369 |
& ( 2. _d 0 *zetaC(I,J)*ep(I,J) - pressC(I,J) |
| 370 |
& ) * hEffM(I,J,bi,bj) |
| 371 |
seaice_tension(I,J) = 2. _d 0*zetaC(I,J) |
| 372 |
& * em(I,J) * hEffM(I,J,bi,bj) |
| 373 |
seaice_shear (I,J) = |
| 374 |
& 2. _d 0*zetaZ(I,J)*2. _d 0*e12(I,J,bi,bj) |
| 375 |
ENDDO |
| 376 |
ENDDO |
| 377 |
ENDIF |
| 378 |
C |
| 379 |
C first step stress equations |
| 380 |
C |
| 381 |
DO j=0,sNy |
| 382 |
DO i=0,sNx |
| 383 |
C sigma1 and sigma2 are computed on C points |
| 384 |
seaice_sigma1 (I,J,bi,bj) = ( seaice_sigma1 (I,J,bi,bj) |
| 385 |
& + recip_evpAlpha * seaice_div(I,J) |
| 386 |
& ) * denom1 |
| 387 |
& *hEffM(I,J,bi,bj) |
| 388 |
seaice_sigma2 (I,J,bi,bj) = ( seaice_sigma2 (I,J,bi,bj) |
| 389 |
& + recip_evpAlpha * seaice_tension(I,J) |
| 390 |
& ) * denom2 |
| 391 |
& *hEffM(I,J,bi,bj) |
| 392 |
#ifdef SEAICE_EVP_ELIMINATE_UNDERFLOWS |
| 393 |
C Code to avoid very small numbers that can degrade performance. |
| 394 |
C Many compilers can handle this more efficiently with the help of |
| 395 |
C a flag (copied from CICE after correspondence with Elizabeth Hunke) |
| 396 |
seaice_sigma1(I,J,bi,bj) = SIGN(MAX( |
| 397 |
& ABS( seaice_sigma1(I,J,bi,bj) ), SEAICE_EPS ), |
| 398 |
& seaice_sigma1(I,J,bi,bj) ) |
| 399 |
seaice_sigma2(I,J,bi,bj) = SIGN(MAX( |
| 400 |
& ABS( seaice_sigma2(I,J,bi,bj) ), SEAICE_EPS ), |
| 401 |
& seaice_sigma2(I,J,bi,bj) ) |
| 402 |
#endif /* SEAICE_EVP_ELIMINATE_UNDERFLOWS */ |
| 403 |
C recover sigma11 and sigma22 |
| 404 |
sig11(I,J) = 0.5 _d 0 * |
| 405 |
& ( seaice_sigma1(I,J,bi,bj)+seaice_sigma2(I,J,bi,bj) ) |
| 406 |
sig22(I,J) = 0.5 _d 0 * |
| 407 |
& ( seaice_sigma1(I,J,bi,bj)-seaice_sigma2(I,J,bi,bj) ) |
| 408 |
ENDDO |
| 409 |
ENDDO |
| 410 |
|
| 411 |
C sigma12 is computed on Z points |
| 412 |
DO j=1,sNy+1 |
| 413 |
DO i=1,sNx+1 |
| 414 |
seaice_sigma12(I,J,bi,bj) = ( seaice_sigma12(I,J,bi,bj) |
| 415 |
& + 0.5 _d 0 * recip_evpAlpha * seaice_shear(I,J) |
| 416 |
& ) * denom2 |
| 417 |
#ifdef SEAICE_EVP_ELIMINATE_UNDERFLOWS |
| 418 |
seaice_sigma12(I,J,bi,bj) = SIGN(MAX( |
| 419 |
& ABS( seaice_sigma12(I,J,bi,bj) ), SEAICE_EPS ), |
| 420 |
& seaice_sigma12(I,J,bi,bj) ) |
| 421 |
#endif /* SEAICE_EVP_ELIMINATE_UNDERFLOWS */ |
| 422 |
ENDDO |
| 423 |
ENDDO |
| 424 |
C |
| 425 |
C compute divergence of stress tensor |
| 426 |
C |
| 427 |
DO J=1,sNy |
| 428 |
DO I=1,sNx |
| 429 |
stressDivergenceX(I,J,bi,bj) = |
| 430 |
& ( sig11(I ,J ) * _dyF(I ,J,bi,bj) |
| 431 |
& - sig11(I-1,J ) * _dyF(I-1,J,bi,bj) |
| 432 |
& + seaice_sigma12(I,J+1,bi,bj) * _dxV(I,J+1,bi,bj) |
| 433 |
& - seaice_sigma12(I,J ,bi,bj) * _dxV(I,J ,bi,bj) |
| 434 |
& ) * recip_rAw(I,J,bi,bj) |
| 435 |
stressDivergenceY(I,J,bi,bj) = |
| 436 |
& ( sig22(I,J ) * _dxF(I,J ,bi,bj) |
| 437 |
& - sig22(I,J-1) * _dxF(I,J-1,bi,bj) |
| 438 |
& + seaice_sigma12(I+1,J,bi,bj) * _dyU(I+1,J,bi,bj) |
| 439 |
& - seaice_sigma12(I ,J,bi,bj) * _dyU(I ,J,bi,bj) |
| 440 |
& ) * recip_rAs(I,J,bi,bj) |
| 441 |
ENDDO |
| 442 |
ENDDO |
| 443 |
ENDDO |
| 444 |
ENDDO |
| 445 |
|
| 446 |
#ifdef ALLOW_AUTODIFF_TAMC |
| 447 |
CADJ STORE stressDivergenceX = comlev1_evp, |
| 448 |
CADJ & key = ikeyloc, byte = isbyte |
| 449 |
CADJ STORE stressDivergenceY = comlev1_evp, |
| 450 |
CADJ & key = ikeyloc, byte = isbyte |
| 451 |
#endif /* ALLOW_AUTODIFF_TAMC */ |
| 452 |
|
| 453 |
|
| 454 |
#ifdef ALLOW_AUTODIFF_TAMC |
| 455 |
#ifdef SEAICE_DYN_STABLE_ADJOINT |
| 456 |
Cgf zero out adjoint fields to stabilize pkg/seaice dyna. adjoint |
| 457 |
CALL ZERO_ADJ( 1, stressDivergenceX, myThid) |
| 458 |
CALL ZERO_ADJ( 1, stressDivergenceY, myThid) |
| 459 |
#endif |
| 460 |
#endif /* ALLOW_AUTODIFF_TAMC */ |
| 461 |
|
| 462 |
C |
| 463 |
C set up rhs for stepping the velocity field |
| 464 |
C |
| 465 |
CALL SEAICE_OCEANDRAG_COEFFS( |
| 466 |
I uIce, vIce, |
| 467 |
O DWATN, |
| 468 |
I iEVPstep, myTime, myIter, myThid ) |
| 469 |
|
| 470 |
DO bj=myByLo(myThid),myByHi(myThid) |
| 471 |
DO bi=myBxLo(myThid),myBxHi(myThid) |
| 472 |
DO J=1,sNy |
| 473 |
DO I=1,sNx |
| 474 |
C over open water, all terms that contain sea ice mass drop out and |
| 475 |
C the balance is determined by the atmosphere-ice and ice-ocean stress; |
| 476 |
C the staggering of uIce and vIce can cause stripes in the open ocean |
| 477 |
C solution when the turning angle is non-zero (SINWAT.NE.0); |
| 478 |
C we mask this term here in order to avoid the stripes and because |
| 479 |
C over open ocean, u/vIce do not advect anything, so that the associated |
| 480 |
C error is small and most likely only confinded to the ice edge but may |
| 481 |
C propagate into the ice covered regions. |
| 482 |
locMaskU = seaiceMassU(I,J,bi,bj) |
| 483 |
locMaskV = seaiceMassV(I,J,bi,bj) |
| 484 |
IF ( locMaskU .NE. 0. _d 0 ) locMaskU = 1. _d 0 |
| 485 |
IF ( locMaskV .NE. 0. _d 0 ) locMaskV = 1. _d 0 |
| 486 |
C to recover old results replace the above lines with the line below |
| 487 |
C locMaskU = 1. _d 0 |
| 488 |
C locMaskV = 1. _d 0 |
| 489 |
C set up anti symmetric drag force and add in ice ocean stress |
| 490 |
C ( remember to average to correct velocity points ) |
| 491 |
FORCEX(I,J,bi,bj)=FORCEX0(I,J,bi,bj)+ |
| 492 |
& 0.5 _d 0 * ( DWATN(I,J,bi,bj)+DWATN(I-1,J,bi,bj) ) * |
| 493 |
& COSWAT * uVel(I,J,kSrf,bi,bj) |
| 494 |
& - SIGN(SINWAT, _fCori(I,J,bi,bj))* 0.5 _d 0 * |
| 495 |
& ( DWATN(I ,J,bi,bj) * 0.5 _d 0 * |
| 496 |
& (vVel(I ,J ,kSrf,bi,bj)-vIce(I ,J ,bi,bj) |
| 497 |
& +vVel(I ,J+1,kSrf,bi,bj)-vIce(I ,J+1,bi,bj)) |
| 498 |
& + DWATN(I-1,J,bi,bj) * 0.5 _d 0 * |
| 499 |
& (vVel(I-1,J ,kSrf,bi,bj)-vIce(I-1,J ,bi,bj) |
| 500 |
& +vVel(I-1,J+1,kSrf,bi,bj)-vIce(I-1,J+1,bi,bj)) |
| 501 |
& )*locMaskU |
| 502 |
FORCEY(I,J,bi,bj)=FORCEY0(I,J,bi,bj)+ |
| 503 |
& 0.5 _d 0 * ( DWATN(I,J,bi,bj)+DWATN(I,J-1,bi,bj) ) * |
| 504 |
& COSWAT * vVel(I,J,kSrf,bi,bj) |
| 505 |
& + SIGN(SINWAT, _fCori(I,J,bi,bj)) * 0.5 _d 0 * |
| 506 |
& ( DWATN(I,J ,bi,bj) * 0.5 _d 0 * |
| 507 |
& (uVel(I ,J ,kSrf,bi,bj)-uIce(I ,J ,bi,bj) |
| 508 |
& +uVel(I+1,J ,kSrf,bi,bj)-uIce(I+1,J ,bi,bj)) |
| 509 |
& + DWATN(I,J-1,bi,bj) * 0.5 _d 0 * |
| 510 |
& (uVel(I ,J-1,kSrf,bi,bj)-uIce(I ,J-1,bi,bj) |
| 511 |
& +uVel(I+1,J-1,kSrf,bi,bj)-uIce(I+1,J-1,bi,bj)) |
| 512 |
& )*locMaskV |
| 513 |
C coriols terms |
| 514 |
FORCEX(I,J,bi,bj)=FORCEX(I,J,bi,bj) + 0.5 _d 0*( |
| 515 |
& seaiceMassC(I ,J,bi,bj) * _fCori(I ,J,bi,bj) |
| 516 |
& * 0.5 _d 0*( vIce(I ,J,bi,bj)+vIce(I ,J+1,bi,bj) ) |
| 517 |
& + seaiceMassC(I-1,J,bi,bj) * _fCori(I-1,J,bi,bj) |
| 518 |
& * 0.5 _d 0*( vIce(I-1,J,bi,bj)+vIce(I-1,J+1,bi,bj) ) |
| 519 |
& ) |
| 520 |
FORCEY(I,J,bi,bj)=FORCEY(I,J,bi,bj) - 0.5 _d 0*( |
| 521 |
& seaiceMassC(I,J ,bi,bj) * _fCori(I,J ,bi,bj) |
| 522 |
& * 0.5 _d 0*( uIce(I,J ,bi,bj)+uIce(I+1, J,bi,bj) ) |
| 523 |
& + seaiceMassC(I,J-1,bi,bj) * _fCori(I,J-1,bi,bj) |
| 524 |
& * 0.5 _d 0*( uIce(I,J-1,bi,bj)+uIce(I+1,J-1,bi,bj) ) |
| 525 |
& ) |
| 526 |
ENDDO |
| 527 |
ENDDO |
| 528 |
C |
| 529 |
C step momentum equations with ice-ocean stress term treated implicitly |
| 530 |
C |
| 531 |
DO J=1,sNy |
| 532 |
DO I=1,sNx |
| 533 |
uIce(I,J,bi,bj) = seaiceMaskU(I,J,bi,bj) * |
| 534 |
& ( seaiceMassU(I,J,bi,bj)*betaFac |
| 535 |
& * uIce(I,J,bi,bj) |
| 536 |
& + seaiceMassU(I,J,bi,bj)*recip_deltaT*evpStarFac |
| 537 |
& * uIceNm1(I,J,bi,bj) |
| 538 |
& + FORCEX(I,J,bi,bj) |
| 539 |
& + stressDivergenceX(I,J,bi,bj) ) |
| 540 |
& /( 1. _d 0 - seaiceMaskU(I,J,bi,bj) |
| 541 |
& + seaiceMassU(I,J,bi,bj)*betaFacP1 |
| 542 |
& + 0.5 _d 0*( DWATN(I,J,bi,bj) + DWATN(I-1,J,bi,bj) ) |
| 543 |
& * COSWAT ) |
| 544 |
vIce(I,J,bi,bj) = seaiceMaskV(I,J,bi,bj) * |
| 545 |
& ( seaiceMassV(I,J,bi,bj)*betaFac |
| 546 |
& * vIce(I,J,bi,bj) |
| 547 |
& + seaiceMassV(I,J,bi,bj)*recip_deltaT*evpStarFac |
| 548 |
& * vIceNm1(I,J,bi,bj) |
| 549 |
& + FORCEY(I,J,bi,bj) |
| 550 |
& + stressDivergenceY(I,J,bi,bj) ) |
| 551 |
& /( 1. _d 0 - seaiceMaskV(I,J,bi,bj) |
| 552 |
& + seaiceMassV(I,J,bi,bj)*betaFacP1 |
| 553 |
& + 0.5 _d 0*( DWATN(I,J,bi,bj) + DWATN(I,J-1,bi,bj) ) |
| 554 |
& * COSWAT ) |
| 555 |
C-- to change results of lab_sea.hb87 test exp. (only preserve 2 digits for cg2d) |
| 556 |
c uIce(i,j,bi,bj) = uIceNm1(i,j,bi,bj) |
| 557 |
c & +( uIce(i,j,bi,bj) - uIceNm1(i,j,bi,bj) ) |
| 558 |
c vIce(i,j,bi,bj) = vIceNm1(i,j,bi,bj) |
| 559 |
c & +( vIce(i,j,bi,bj) - vIceNm1(i,j,bi,bj) ) |
| 560 |
ENDDO |
| 561 |
ENDDO |
| 562 |
#ifndef OBCS_UVICE_OLD |
| 563 |
DO j=1,sNy |
| 564 |
DO i=1,sNx |
| 565 |
locMaskU = maskInC(i,j,bi,bj)*maskInC(i-1,j,bi,bj) |
| 566 |
locMaskV = maskInC(i,j,bi,bj)*maskInC(i,j-1,bi,bj) |
| 567 |
uIce(i,j,bi,bj) = uIce(i,j,bi,bj)*locMaskU |
| 568 |
& + uIceNm1(i,j,bi,bj)*(ONE-locMaskU) |
| 569 |
vIce(i,j,bi,bj) = vIce(i,j,bi,bj)*locMaskV |
| 570 |
& + vIceNm1(i,j,bi,bj)*(ONE-locMaskV) |
| 571 |
ENDDO |
| 572 |
ENDDO |
| 573 |
#endif /* OBCS_UVICE_OLD */ |
| 574 |
ENDDO |
| 575 |
ENDDO |
| 576 |
|
| 577 |
#ifdef ALLOW_AUTODIFF_TAMC |
| 578 |
CADJ STORE uIce = comlev1_evp, key = ikeyloc, byte = isbyte |
| 579 |
CADJ STORE vIce = comlev1_evp, key = ikeyloc, byte = isbyte |
| 580 |
#endif /* ALLOW_AUTODIFF_TAMC */ |
| 581 |
|
| 582 |
CALL EXCH_UV_XY_RL(uIce,vIce,.TRUE.,myThid) |
| 583 |
|
| 584 |
ENDIF |
| 585 |
C end of the main time loop |
| 586 |
ENDDO |
| 587 |
|
| 588 |
#endif /* SEAICE_ALLOW_DYNAMICS and SEAICE_CGRID and SEAICE_ALLOW_EVP */ |
| 589 |
|
| 590 |
RETURN |
| 591 |
END |
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