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C $Header: /u/gcmpack/models/MITgcmUV/pkg/generic_advdiff/timestep_tracer.F,v 1.4 2001/08/15 15:51:46 adcroft Exp $ |
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C $Name: $ |
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|
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#include "CPP_OPTIONS.h" |
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|
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SUBROUTINE TIMESTEP_TRACER( |
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I bi, bj, iMin, iMax, jMin, jMax, K, |
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I advection_scheme, |
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U tracer, gTracer, gTrNm1, |
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I myIter, myThid ) |
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C /==========================================================\ |
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C | S/R TIMESTEP_TRACER | |
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C | o Step model tracer field forward in time | |
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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 "GAD.h" |
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|
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C == Routine Arguments == |
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INTEGER bi,bj,iMin,iMax,jMin,jMax,K |
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INTEGER advection_scheme |
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_RL tracer (1-OLx:sNx+OLx,1-OLy:sNy+OLy,Nr,nSx,nSy) |
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_RL gTracer(1-OLx:sNx+OLx,1-OLy:sNy+OLy,Nr,nSx,nSy) |
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_RL gTrNm1 (1-OLx:sNx+OLx,1-OLy:sNy+OLy,Nr,nSx,nSy) |
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INTEGER myIter, myThid |
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C == Local variables == |
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INTEGER i,j |
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_RL ab15,ab05 |
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|
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C Adams-Bashforth timestepping weights |
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IF (myIter .EQ. 0) THEN |
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ab15=1.0 |
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ab05=0.0 |
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ELSE |
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ab15=1.5+abEps |
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ab05=-(0.5+abEps) |
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ENDIF |
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|
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C Step forward temperature |
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IF ( advection_scheme.EQ.ENUM_CENTERED_2ND |
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& .OR.advection_scheme.EQ.ENUM_UPWIND_3RD |
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& .OR.advection_scheme.EQ.ENUM_CENTERED_4TH ) THEN |
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DO j=jMin,jMax |
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DO i=iMin,iMax |
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gTrNm1(i,j,k,bi,bj)=tracer(i,j,k,bi,bj) |
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& +deltaTtracer*( |
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& ab15*gTracer(i,j,k,bi,bj) |
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& +ab05*gTrNm1(i,j,k,bi,bj) ) |
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ENDDO |
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ENDDO |
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ELSEIF (advection_scheme.EQ.ENUM_FLUX_LIMIT) THEN |
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DO j=jMin,jMax |
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DO i=iMin,iMax |
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gTrNm1(i,j,k,bi,bj)=tracer(i,j,k,bi,bj) |
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& +deltaTtracer*gTracer(i,j,k,bi,bj) |
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ENDDO |
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ENDDO |
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ELSE |
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STOP 'TIMESTEP_TRACER: Bad advection_scheme' |
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ENDIF |
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|
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RETURN |
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END |