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C $Header: /u/gcmpack/MITgcm/pkg/generic_advdiff/gad_dst3_adv_x.F,v 1.12 2007/04/04 01:39:06 jmc Exp $ |
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C $Name: $ |
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|
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#include "GAD_OPTIONS.h" |
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|
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CBOP |
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C !ROUTINE: GAD_DST3_ADV_X |
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|
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C !INTERFACE: ========================================================== |
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SUBROUTINE GAD_DST3_ADV_X( |
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I bi,bj,k, calcCFL, deltaTloc, |
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I uTrans, uFld, |
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I maskLocW, tracer, |
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O uT, |
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I myThid ) |
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|
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C !DESCRIPTION: |
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C Calculates the area integrated zonal flux due to advection of a |
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C tracer using 3rd-order Direct Space and Time (DST-3) Advection Scheme |
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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 "GRID.h" |
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#include "EEPARAMS.h" |
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#include "PARAMS.h" |
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#include "GAD.h" |
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|
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C == Routine arguments == |
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C !INPUT PARAMETERS: =================================================== |
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C bi,bj :: tile indices |
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C k :: vertical level |
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C calcCFL :: =T: calculate CFL number ; =F: take uFld as CFL. |
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C deltaTloc :: local time-step (s) |
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C uTrans :: zonal volume transport |
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C uFld :: zonal flow / CFL number |
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C tracer :: tracer field |
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C myThid :: thread number |
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INTEGER bi,bj,k |
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LOGICAL calcCFL |
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_RL deltaTloc |
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_RL uTrans(1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RL uFld (1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RS maskLocW(1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RL tracer(1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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INTEGER myThid |
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|
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C !OUTPUT PARAMETERS: ================================================== |
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C uT :: zonal advective flux |
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_RL uT (1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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|
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C == Local variables == |
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C !LOCAL VARIABLES: ==================================================== |
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C i,j :: loop indices |
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C uCFL :: Courant-Friedrich-Levy number |
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INTEGER i,j |
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_RL Rjm,Rj,Rjp,uCFL,d0,d1 |
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#ifdef OLD_DST3_FORMULATION |
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_RL psiP,psiM,thetaP,thetaM |
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_RL smallNo |
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c _RL Rjjm,Rjjp |
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|
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IF (inAdMode) THEN |
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smallNo = 1.0D-20 |
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ELSE |
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smallNo = 1.0D-20 |
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ENDIF |
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#endif |
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|
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DO j=1-Oly,sNy+Oly |
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uT(1-Olx,j)=0. |
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uT(2-Olx,j)=0. |
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uT(sNx+Olx,j)=0. |
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ENDDO |
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DO j=1-Oly,sNy+Oly |
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DO i=1-Olx+2,sNx+Olx-1 |
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Rjp=(tracer(i+1,j)-tracer( i ,j))*maskLocW(i+1,j) |
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Rj =(tracer( i ,j)-tracer(i-1,j))*maskLocW( i ,j) |
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Rjm=(tracer(i-1,j)-tracer(i-2,j))*maskLocW(i-1,j) |
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|
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uCFL = uFld(i,j) |
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IF ( calcCFL ) uCFL = ABS( uFld(i,j)*deltaTloc |
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& *recip_dxC(i,j,bi,bj)*recip_deepFacC(k) ) |
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d0=(2.-uCFL)*(1.-uCFL)*oneSixth |
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d1=(1.-uCFL*uCFL)*oneSixth |
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#ifdef OLD_DST3_FORMULATION |
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IF ( ABS(Rj).LT.smallNo .OR. |
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& ABS(Rjm).LT.smallNo ) THEN |
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thetaP=0. |
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psiP=0. |
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ELSE |
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thetaP=(Rjm+smallNo)/(smallNo+Rj) |
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psiP=d0+d1*thetaP |
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ENDIF |
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IF ( ABS(Rj).LT.smallNo .OR. |
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& ABS(Rjp).LT.smallNo ) THEN |
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thetaM=0. |
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psiM=0. |
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ELSE |
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thetaM=(Rjp+smallNo)/(smallNo+Rj) |
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psiM=d0+d1*thetaM |
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ENDIF |
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uT(i,j)= |
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& 0.5*(uTrans(i,j)+ABS(uTrans(i,j))) |
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& *( Tracer(i-1,j) + psiP*Rj ) |
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& +0.5*(uTrans(i,j)-ABS(uTrans(i,j))) |
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& *( Tracer( i ,j) - psiM*Rj ) |
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#else /* OLD_DST3_FORMULATION */ |
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uT(i,j)= |
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& 0.5*(uTrans(i,j)+ABS(uTrans(i,j))) |
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& *( Tracer(i-1,j) + (d0*Rj+d1*Rjm) ) |
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& +0.5*(uTrans(i,j)-ABS(uTrans(i,j))) |
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& *( Tracer( i ,j) - (d0*Rj+d1*Rjp) ) |
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#endif /* OLD_DST3_FORMULATION */ |
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|
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ENDDO |
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ENDDO |
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|
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RETURN |
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END |