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C $Header: /u/gcmpack/MITgcm/pkg/seaice/seaice_calc_strainrates.F,v 1.11 2009/03/18 12:58:17 mlosch Exp $ |
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C $Name: $ |
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|
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#include "SEAICE_OPTIONS.h" |
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|
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CStartOfInterface |
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SUBROUTINE SEAICE_CALC_STRAINRATES( |
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I uFld, vFld, |
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O e11Loc, e22Loc, e12Loc, |
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I kSize, iStep, myTime, myIter, myThid ) |
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C /==========================================================\ |
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C | SUBROUTINE SEAICE_CALC_STRAINRATES | |
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C | o compute strain rates from ice velocities | |
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C |==========================================================| |
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C | written by Martin Losch, Apr 2007 | |
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C \==========================================================/ |
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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 "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 === Routine arguments === |
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C iStep :: Sub-time-step number |
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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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C kSize :: length of 3rd dimension of velocity variables |
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INTEGER iStep |
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_RL myTime |
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INTEGER myIter |
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INTEGER myThid |
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INTEGER kSize |
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C ice velocities |
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_RL uFld(1-Olx:sNx+Olx,1-Oly:sNy+Oly,kSize,nSx,nSy) |
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_RL vFld(1-Olx:sNx+Olx,1-Oly:sNy+Oly,kSize,nSx,nSy) |
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C strain rate tensor |
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_RL e11Loc (1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy) |
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_RL e22Loc (1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy) |
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_RL e12Loc (1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy) |
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CEndOfInterface |
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|
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#ifdef SEAICE_CGRID |
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#ifdef SEAICE_ALLOW_DYNAMICS |
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C === Local variables === |
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C i,j,bi,bj - Loop counters |
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INTEGER i, j, bi, bj |
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C hFacU, hFacV - determine the no-slip boundary condition |
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INTEGER k |
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_RS hFacU, hFacV, noSlipFac |
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|
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k = 1 |
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noSlipFac = 0. _d 0 |
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IF ( SEAICE_no_slip ) noSlipFac = 1. _d 0 |
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C |
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#ifndef SEAICE_OLD_AND_BAD_DISCRETIZATION |
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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-1 |
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DO i=1-Olx,sNx+Olx-1 |
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C evaluate strain rates |
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e11Loc(I,J,bi,bj) = _recip_dxF(I,J,bi,bj) * |
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& (uFld(I+1,J,1,bi,bj)-uFld(I,J,1,bi,bj)) |
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& +HALF* |
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& (vFld(I,J,1,bi,bj)+vFld(I,J+1,1,bi,bj)) |
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& * k2AtC(I,J,bi,bj) |
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e22Loc(I,J,bi,bj) = _recip_dyF(I,J,bi,bj) * |
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& (vFld(I,J+1,1,bi,bj)-vFld(I,J,1,bi,bj)) |
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& +HALF* |
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& (uFld(I,J,1,bi,bj)+uFld(I+1,J,1,bi,bj)) |
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& * k1AtC(I,J,bi,bj) |
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C one metric term is missing |
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ENDDO |
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ENDDO |
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DO j=1-Oly+1,sNy+Oly |
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DO i=1-Olx+1,sNx+Olx |
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hFacU = _maskW(i,j,k,bi,bj) - _maskW(i,j-1,k,bi,bj) |
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hFacV = _maskS(i,j,k,bi,bj) - _maskS(i-1,j,k,bi,bj) |
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e12Loc(I,J,bi,bj) = HALF*( |
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& ( uFld(I,J,1,bi,bj) - uFld(I ,J-1,1,bi,bj) ) |
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& * _recip_dyU(I,J,bi,bj) |
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& + ( vFld(I,J,1,bi,bj) - vFld(I-1,J ,1,bi,bj) ) |
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& * _recip_dxV(I,J,bi,bj) |
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& - k1AtZ(I,J,bi,bj) |
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& * 0.5 _d 0 * (vFld(I,J,1,bi,bj)+vFld(I-1,J ,1,bi,bj)) |
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& - k2AtZ(I,J,bi,bj) |
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& * 0.5 _d 0 * (uFld(I,J,1,bi,bj)+uFld(I ,J-1,1,bi,bj)) |
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& ) |
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& *maskC(I ,J ,k,bi,bj)*maskC(I-1,J ,k,bi,bj) |
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& *maskC(I ,J-1,k,bi,bj)*maskC(I-1,J-1,k,bi,bj) |
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& + 2.0 _d 0 * noSlipFac * ( |
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& ( uFld(I,J,1,bi,bj) + uFld(I ,J-1,1,bi,bj) ) |
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& * _recip_dyU(I,J,bi,bj) * hFacU |
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& + ( vFld(I,J,1,bi,bj) + vFld(I-1,J ,1,bi,bj) ) |
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& * _recip_dxV(I,J,bi,bj) * hFacV |
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& ) |
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C no slip at the boundary implies u(j)+u(j-1)=0 and v(i)+v(i-1)=0 |
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C accross the boundary; this is already accomplished by masking so |
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C that the following lines are not necessary |
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c$$$ & - hFacV * k1AtZ(I,J,bi,bj) |
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c$$$ & * 0.5 _d 0 * (vFld(I,J,1,bi,bj)+vFld(I-1,J ,1,bi,bj)) |
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c$$$ & - hFacU * k2AtZ(I,J,bi,bj) |
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c$$$ & * 0.5 _d 0 * (uFld(I,J,1,bi,bj)+uFld(I ,J-1,1,bi,bj)) |
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ENDDO |
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ENDDO |
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|
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c$$$ ENDIF |
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ENDDO |
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ENDDO |
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#else |
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C this the old and incomplete discretization, here I also erroneously |
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C used finite-volumes to discretize the strain rates |
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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-1 |
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DO i=1-Olx,sNx+Olx-1 |
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C evaluate strain rates |
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e11Loc(I,J,bi,bj) = _recip_dxF(I,J,bi,bj) * |
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& (uFld(I+1,J,1,bi,bj)-uFld(I,J,1,bi,bj)) |
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& -HALF* |
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& (vFld(I,J,1,bi,bj)+vFld(I,J+1,1,bi,bj)) |
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& * _tanPhiAtU(I,J,bi,bj)*recip_rSphere |
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e22Loc(I,J,bi,bj) = _recip_dyF(I,J,bi,bj) * |
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& (vFld(I,J+1,1,bi,bj)-vFld(I,J,1,bi,bj)) |
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C one metric term is missing |
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ENDDO |
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ENDDO |
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DO j=1-Oly+1,sNy+Oly |
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DO i=1-Olx+1,sNx+Olx |
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e12Loc(I,J,bi,bj) = HALF*( |
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& (uFld(I ,J ,1,bi,bj) * _dxC(I ,J ,bi,bj) |
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& -uFld(I ,J-1,1,bi,bj) * _dxC(I ,J-1,bi,bj) |
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& +vFld(I ,J ,1,bi,bj) * _dyC(I ,J ,bi,bj) |
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& -vFld(I-1,J ,1,bi,bj) * _dyC(I-1,J ,bi,bj)) |
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& * recip_rAz(I,J,bi,bj) |
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& + |
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& 0.25 _d 0 * (uFld(I,J,1,bi,bj)+uFld(I ,J-1,1,bi,bj)) |
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& * ( _tanPhiAtU(I,J,bi,bj) + _tanPhiAtU(I,J-1,bi,bj) ) |
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& *recip_rSphere |
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& ) |
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& *maskC(I ,J ,k,bi,bj)*maskC(I-1,J ,k,bi,bj) |
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& *maskC(I ,J-1,k,bi,bj)*maskC(I-1,J-1,k,bi,bj) |
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C one metric term is missing |
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ENDDO |
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ENDDO |
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IF ( SEAICE_no_slip ) THEN |
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C no slip boundary conditions apply only to e12Loc |
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DO j=1-Oly+1,sNy+Oly |
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DO i=1-Olx+1,sNx+Olx |
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hFacU = _maskW(i,j,k,bi,bj) - _maskW(i,j-1,k,bi,bj) |
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hFacV = _maskS(i,j,k,bi,bj) - _maskS(i-1,j,k,bi,bj) |
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|
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e12Loc(I,J,bi,bj) = e12Loc(I,J,bi,bj) |
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& + recip_rAz(i,j,bi,bj) * 2. _d 0 * |
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& ( hFacU * ( _dxC(i,j-1,bi,bj)*uFld(i,j ,1,bi,bj) |
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& + _dxC(i,j, bi,bj)*uFld(i,j-1,1,bi,bj) ) |
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& + hFacV * ( _dyC(i-1,j,bi,bj)*vFld(i ,j,1,bi,bj) |
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& + _dyC(i, j,bi,bj)*vFld(i-1,j,1,bi,bj) ) ) |
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& - hFacU |
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& * 0.25 _d 0 * (uFld(I,J,1,bi,bj)+uFld(I ,J-1,1,bi,bj)) |
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& * ( _tanPhiAtU(I,J,bi,bj) + _tanPhiAtU(I,J-1,bi,bj) ) |
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& *recip_rSphere |
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C one metric term is missing |
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ENDDO |
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ENDDO |
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|
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ENDIF |
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ENDDO |
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ENDDO |
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#endif /* SEAICE_OLD_AND_BAD_DISCRETIZATION */ |
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#endif /* SEAICE_ALLOW_DYNAMICS */ |
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#endif /* SEAICE_CGRID */ |
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RETURN |
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END |