pkg/generic_advdiff/timestep_tracer.F

C $Header: /u/gcmpack/models/MITgcmUV/pkg/generic_advdiff/timestep_tracer.F,v 1.2 2001/07/12 00:31:59 jmc Exp $
C $Name:  $

#include "CPP_OPTIONS.h"

      SUBROUTINE TIMESTEP_TRACER(
     I                     bi, bj, iMin, iMax, jMin, jMax, K, tauAB,
     U                     tracer, gTracer, gTrNm1,
     I                     myIter, myThid )
C     /==========================================================\
C     | S/R TIMESTEP_TRACER                                      |
C     | o Step model tracer field forward in time                |
C     \==========================================================/
      IMPLICIT NONE

C     == Global variables ===
#include "SIZE.h"
#include "EEPARAMS.h"
#include "PARAMS.h"
#include "GAD.h"

C     == Routine Arguments ==
C     tauAB - Adams-Bashforth timestepping weight: 0=forward ; 1/2=Adams-Bashf.
      INTEGER bi,bj,iMin,iMax,jMin,jMax,K
      _RL  tauAB
      _RL  tracer (1-OLx:sNx+OLx,1-OLy:sNy+OLy,Nr,nSx,nSy)
      _RL  gTracer(1-OLx:sNx+OLx,1-OLy:sNy+OLy,Nr,nSx,nSy)
      _RL  gTrNm1 (1-OLx:sNx+OLx,1-OLy:sNy+OLy,Nr,nSx,nSy)
      INTEGER myIter, myThid
C     == Local variables ==
      INTEGER i,j
      _RL ab15,ab05

C     Adams-Bashforth timestepping weights
      IF (myIter .EQ. 0) THEN
       ab15=1.0
       ab05=0.0
      ELSE
       ab15=1.+tauAB
       ab05=-tauAB
      ENDIF

C     Step forward temperature
      IF ( gad_advection_scheme.EQ.ENUM_CENTERED_2ND
     & .OR.gad_advection_scheme.EQ.ENUM_UPWIND_3RD
     & .OR.gad_advection_scheme.EQ.ENUM_CENTERED_4TH ) THEN
       DO j=jMin,jMax
        DO i=iMin,iMax
          gTrNm1(i,j,k,bi,bj)=tracer(i,j,k,bi,bj)
     &             +deltaTtracer*(
     &                              ab15*gTracer(i,j,k,bi,bj)
     &                             +ab05*gTrNm1(i,j,k,bi,bj)  )
        ENDDO
       ENDDO
      ELSEIF (gad_advection_scheme.EQ.ENUM_FLUX_LIMIT) THEN
       DO j=jMin,jMax
        DO i=iMin,iMax
          gTrNm1(i,j,k,bi,bj)=tracer(i,j,k,bi,bj)
     &             +deltaTtracer*gTracer(i,j,k,bi,bj)
        ENDDO
       ENDDO
      ELSE
       STOP 'TIMESTEP_TRACER: Bad gad_advection_scheme'
      ENDIF

      RETURN
      END
1	C $Header: /u/gcmpack/models/MITgcmUV/pkg/generic_advdiff/timestep_tracer.F,v 1.2 2001/07/12 00:31:59 jmc Exp $
2	C $Name: $
3
4	#include "CPP_OPTIONS.h"
5
6	SUBROUTINE TIMESTEP_TRACER(
7	I bi, bj, iMin, iMax, jMin, jMax, K, tauAB,
8	U tracer, gTracer, gTrNm1,
9	I myIter, myThid )
10	C /==========================================================\
11	C \| S/R TIMESTEP_TRACER \|
12	C \| o Step model tracer field forward in time \|
13	C \==========================================================/
14	IMPLICIT NONE
15
16	C == Global variables ===
17	#include "SIZE.h"
18	#include "EEPARAMS.h"
19	#include "PARAMS.h"
20	#include "GAD.h"
21
22	C == Routine Arguments ==
23	C tauAB - Adams-Bashforth timestepping weight: 0=forward ; 1/2=Adams-Bashf.
24	INTEGER bi,bj,iMin,iMax,jMin,jMax,K
25	_RL tauAB
26	_RL tracer (1-OLx:sNx+OLx,1-OLy:sNy+OLy,Nr,nSx,nSy)
27	_RL gTracer(1-OLx:sNx+OLx,1-OLy:sNy+OLy,Nr,nSx,nSy)
28	_RL gTrNm1 (1-OLx:sNx+OLx,1-OLy:sNy+OLy,Nr,nSx,nSy)
29	INTEGER myIter, myThid
30	C == Local variables ==
31	INTEGER i,j
32	_RL ab15,ab05
33
34	C Adams-Bashforth timestepping weights
35	IF (myIter .EQ. 0) THEN
36	ab15=1.0
37	ab05=0.0
38	ELSE
39	ab15=1.+tauAB
40	ab05=-tauAB
41	ENDIF
42
43	C Step forward temperature
44	IF ( gad_advection_scheme.EQ.ENUM_CENTERED_2ND
45	& .OR.gad_advection_scheme.EQ.ENUM_UPWIND_3RD
46	& .OR.gad_advection_scheme.EQ.ENUM_CENTERED_4TH ) THEN
47	DO j=jMin,jMax
48	DO i=iMin,iMax
49	gTrNm1(i,j,k,bi,bj)=tracer(i,j,k,bi,bj)
50	& +deltaTtracer*(
51	& ab15*gTracer(i,j,k,bi,bj)
52	& +ab05*gTrNm1(i,j,k,bi,bj) )
53	ENDDO
54	ENDDO
55	ELSEIF (gad_advection_scheme.EQ.ENUM_FLUX_LIMIT) THEN
56	DO j=jMin,jMax
57	DO i=iMin,iMax
58	gTrNm1(i,j,k,bi,bj)=tracer(i,j,k,bi,bj)
59	& +deltaTtracer*gTracer(i,j,k,bi,bj)
60	ENDDO
61	ENDDO
62	ELSE
63	STOP 'TIMESTEP_TRACER: Bad gad_advection_scheme'
64	ENDIF
65
66	RETURN
67	END