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C $Header: /u/gcmpack/MITgcm/model/src/update_etah.F,v 1.7 2005/11/04 01:19:24 jmc Exp $ |
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C $Name: $ |
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|
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#include "PACKAGES_CONFIG.h" |
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#include "CPP_OPTIONS.h" |
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|
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CBOP |
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C !ROUTINE: UPDATE_ETAH |
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C !INTERFACE: |
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SUBROUTINE UPDATE_ETAH( myTime, myIter, myThid ) |
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C !DESCRIPTION: \bv |
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C *==========================================================* |
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C | SUBROUTINE UPDATE_ETAH |
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C | o Update etaH at the begining of the time step. |
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C | (required with NLFS to derive surface layer thickness) |
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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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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 "SURFACE.h" |
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#include "FFIELDS.h" |
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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 :: Current time in simulation |
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C myIter :: Current iteration number in simulation |
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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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|
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C !LOCAL VARIABLES: |
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#ifdef EXACT_CONSERV |
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C Local variables in common block |
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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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INTEGER i,j,bi,bj |
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CEOP |
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|
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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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|
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C---+----1----+----2----+----3----+----4----+----5----+----6----+----7-|--+----| |
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|
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C-- before updating etaH, save current etaH field in etaHnm1 |
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DO j=1-Oly,sNy+Oly |
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DO i=1-Olx,sNx+Olx |
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etaHnm1(i,j,bi,bj) = etaH(i,j,bi,bj) |
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ENDDO |
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ENDDO |
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|
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C-- Update etaH at the end of the time step : |
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C Incorporate the Explicit part of -Divergence(Barotropic_Flow) |
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|
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IF (implicDiv2Dflow.EQ. 1. _d 0) THEN |
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DO j=1-Oly,sNy+Oly |
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DO i=1-Olx,sNx+Olx |
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etaH(i,j,bi,bj) = etaN(i,j,bi,bj) |
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ENDDO |
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ENDDO |
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|
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ELSE |
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DO j=1,sNy |
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DO i=1,sNx |
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etaH(i,j,bi,bj) = etaN(i,j,bi,bj) |
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& + (1. - implicDiv2Dflow)*dEtaHdt(i,j,bi,bj) |
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& *deltaTfreesurf |
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ENDDO |
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ENDDO |
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ENDIF |
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|
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#ifdef ALLOW_OBCS |
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C- note (with Non-Lin Free-Surface): |
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C 1) needs to apply OBC to etaH since viscous terms depend on hFacZ. |
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C that is not only function of boundaries hFac values. |
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C 2) has to be done before calc_surf_dr; but since obcs_calc is |
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C called later, hFacZ will lag 1 time step behind OBC update. |
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C 3) avoid also unrealistic value of etaH in OB regions that |
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C might produce many "WARNING" message from calc_surf_dr. |
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C------- |
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C-- Apply OBC to etaH if NonLin-FreeSurf, reset to zero otherwise: |
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IF ( useOBCS ) CALL OBCS_APPLY_ETA( bi, bj, etaH, myThid ) |
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#endif /* ALLOW_OBCS */ |
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|
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C---+----1----+----2----+----3----+----4----+----5----+----6----+----7-|--+----| |
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|
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C- end bi,bj loop. |
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ENDDO |
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ENDDO |
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|
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IF (implicDiv2Dflow .NE. 1. _d 0 .OR. useOBCS ) |
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& _EXCH_XY_RL( etaH, myThid ) |
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|
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c IF (useRealFreshWaterFlux .AND. myTime.EQ.startTime) |
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c & _EXCH_XY_R4( PmEpR, myThid ) |
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|
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#endif /* EXACT_CONSERV */ |
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|
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RETURN |
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END |