pkg/generic_advdiff/timestep_tracer.F

C $Header: /u/gcmpack/models/MITgcmUV/pkg/generic_advdiff/timestep_tracer.F,v 1.4 2001/08/15 15:51:46 adcroft Exp $
C $Name:  $

#include "CPP_OPTIONS.h"

      SUBROUTINE TIMESTEP_TRACER(
     I                     bi, bj, iMin, iMax, jMin, jMax, K,
     I                     advection_scheme,
     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 ==
      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	adcroft	1.5	C $Header: /u/gcmpack/models/MITgcmUV/pkg/generic_advdiff/timestep_tracer.F,v 1.4 2001/08/15 15:51:46 adcroft Exp $
2	adcroft	1.1	C $Name: $
3
4			#include "CPP_OPTIONS.h"
5
6			SUBROUTINE TIMESTEP_TRACER(
7	adcroft	1.4	I bi, bj, iMin, iMax, jMin, jMax, K,
8			I advection_scheme,
9	adcroft	1.1	U tracer, gTracer, gTrNm1,
10			I myIter, myThid )
11			C /==========================================================\
12			C \| S/R TIMESTEP_TRACER \|
13			C \| o Step model tracer field forward in time \|
14			C \==========================================================/
15			IMPLICIT NONE
16
17			C == Global variables ===
18			#include "SIZE.h"
19			#include "EEPARAMS.h"
20			#include "PARAMS.h"
21			#include "GAD.h"
22
23			C == Routine Arguments ==
24			INTEGER bi,bj,iMin,iMax,jMin,jMax,K
25	adcroft	1.4	INTEGER advection_scheme
26	adcroft	1.1	_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	adcroft	1.3	IF (myIter .EQ. 0) THEN
36			ab15=1.0
37			ab05=0.0
38			ELSE
39	adcroft	1.4	ab15=1.5+abEps
40			ab05=-(0.5+abEps)
41	adcroft	1.3	ENDIF
42	adcroft	1.1
43			C Step forward temperature
44	adcroft	1.4	IF ( advection_scheme.EQ.ENUM_CENTERED_2ND
45			& .OR.advection_scheme.EQ.ENUM_UPWIND_3RD
46			& .OR.advection_scheme.EQ.ENUM_CENTERED_4TH ) THEN
47	adcroft	1.1	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	adcroft	1.4	ELSEIF (advection_scheme.EQ.ENUM_FLUX_LIMIT) THEN
56	adcroft	1.1	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	adcroft	1.4	STOP 'TIMESTEP_TRACER: Bad advection_scheme'
64	adcroft	1.1	ENDIF
65
66			RETURN
67			END