model/src/timestep_tracer.F

C $Header: /u/gcmpack/models/MITgcmUV/model/src/timestep_tracer.F,v 1.3 2001/07/31 15:01:33 adcroft Exp $
C $Name:  $

#include "CPP_OPTIONS.h"

      SUBROUTINE TIMESTEP_TRACER(
     I                     bi, bj, iMin, iMax, jMin, jMax, K,
     I                     advection_scheme,
     I                     tracer, gTracer,
     O                     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 ==
      INTEGER bi,bj,iMin,iMax,jMin,jMax,K
      INTEGER advection_scheme
      _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=1.5+abEps
       ab05=-(0.5+abEps)
      ENDIF

C     Step forward temperature
      IF ( advection_scheme.EQ.ENUM_CENTERED_2ND
     & .OR.advection_scheme.EQ.ENUM_UPWIND_3RD
     & .OR.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 (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 advection_scheme'
      ENDIF

      RETURN
      END
1	C $Header: /u/gcmpack/models/MITgcmUV/model/src/timestep_tracer.F,v 1.3 2001/07/31 15:01:33 adcroft Exp $
2	C $Name: $
3
4	#include "CPP_OPTIONS.h"
5
6	SUBROUTINE TIMESTEP_TRACER(
7	I bi, bj, iMin, iMax, jMin, jMax, K,
8	I advection_scheme,
9	I tracer, gTracer,
10	O gTrNm1,
11	I myIter, myThid )
12	C /==========================================================\
13	C \| S/R TIMESTEP_TRACER \|
14	C \| o Step model tracer field forward in time \|
15	C \==========================================================/
16	IMPLICIT NONE
17
18	C == Global variables ===
19	#include "SIZE.h"
20	#include "EEPARAMS.h"
21	#include "PARAMS.h"
22	#include "GAD.h"
23
24	C == Routine Arguments ==
25	INTEGER bi,bj,iMin,iMax,jMin,jMax,K
26	INTEGER advection_scheme
27	_RL tracer (1-OLx:sNx+OLx,1-OLy:sNy+OLy,Nr,nSx,nSy)
28	_RL gTracer(1-OLx:sNx+OLx,1-OLy:sNy+OLy,Nr,nSx,nSy)
29	_RL gTrNm1 (1-OLx:sNx+OLx,1-OLy:sNy+OLy,Nr,nSx,nSy)
30	INTEGER myIter, myThid
31	C == Local variables ==
32	INTEGER i,j
33	_RL ab15,ab05
34
35	C Adams-Bashforth timestepping weights
36	IF (myIter .EQ. 0) THEN
37	ab15=1.0
38	ab05=0.0
39	ELSE
40	ab15=1.5+abEps
41	ab05=-(0.5+abEps)
42	ENDIF
43
44	C Step forward temperature
45	IF ( advection_scheme.EQ.ENUM_CENTERED_2ND
46	& .OR.advection_scheme.EQ.ENUM_UPWIND_3RD
47	& .OR.advection_scheme.EQ.ENUM_CENTERED_4TH ) THEN
48	DO j=jMin,jMax
49	DO i=iMin,iMax
50	gTrNm1(i,j,k,bi,bj)=tracer(i,j,k,bi,bj)
51	& +deltaTtracer*(
52	& ab15*gTracer(i,j,k,bi,bj)
53	& +ab05*gTrNm1(i,j,k,bi,bj) )
54	ENDDO
55	ENDDO
56	ELSEIF (advection_scheme.EQ.ENUM_FLUX_LIMIT) THEN
57	DO j=jMin,jMax
58	DO i=iMin,iMax
59	gTrNm1(i,j,k,bi,bj)=tracer(i,j,k,bi,bj)
60	& +deltaTtracer*gTracer(i,j,k,bi,bj)
61	ENDDO
62	ENDDO
63	ELSE
64	STOP 'TIMESTEP_TRACER: Bad advection_scheme'
65	ENDIF
66
67	RETURN
68	END