pkg/generic_advdiff/gad_dst3_adv_x.F

C $Header: /u/gcmpack/MITgcm/pkg/generic_advdiff/gad_dst3_adv_x.F,v 1.13 2008/02/29 01:30:59 mlosch Exp $
C $Name:  $

#include "GAD_OPTIONS.h"

CBOP
C !ROUTINE: GAD_DST3_ADV_X

C !INTERFACE: ==========================================================
      SUBROUTINE GAD_DST3_ADV_X(
     I           bi,bj,k, calcCFL, deltaTloc,
     I           uTrans, uFld,
     I           maskLocW, tracer,
     O           uT,
     I           myThid )

C !DESCRIPTION:
C  Calculates the area integrated zonal flux due to advection of a
C  tracer using 3rd-order Direct Space and Time (DST-3) Advection Scheme

C !USES: ===============================================================
      IMPLICIT NONE

C     == GLobal variables ==
#include "SIZE.h"
#ifdef OLD_DST3_FORMULATION
#include "EEPARAMS.h"
#include "PARAMS.h"
#endif
#include "GRID.h"
#include "GAD.h"

C     == Routine arguments ==
C !INPUT PARAMETERS: ===================================================
C  bi,bj             :: tile indices
C  k                 :: vertical level
C  calcCFL           :: =T: calculate CFL number ; =F: take uFld as CFL.
C  deltaTloc         :: local time-step (s)
C  uTrans            :: zonal volume transport
C  uFld              :: zonal flow / CFL number
C  tracer            :: tracer field
C  myThid            :: thread number
      INTEGER bi,bj,k
      LOGICAL calcCFL
      _RL deltaTloc
      _RL uTrans(1-OLx:sNx+OLx,1-OLy:sNy+OLy)
      _RL uFld  (1-OLx:sNx+OLx,1-OLy:sNy+OLy)
      _RS maskLocW(1-OLx:sNx+OLx,1-OLy:sNy+OLy)
      _RL tracer(1-OLx:sNx+OLx,1-OLy:sNy+OLy)
      INTEGER myThid

C !OUTPUT PARAMETERS: ==================================================
C  uT                :: zonal advective flux
      _RL uT    (1-OLx:sNx+OLx,1-OLy:sNy+OLy)

C     == Local variables ==
C !LOCAL VARIABLES: ====================================================
C  i,j               :: loop indices
C  uCFL              :: Courant-Friedrich-Levy number
      INTEGER i,j
      _RL Rjm,Rj,Rjp,uCFL,d0,d1
#ifdef OLD_DST3_FORMULATION
      _RL psiP,psiM,thetaP,thetaM
      _RL smallNo
c     _RL Rjjm,Rjjp

      IF (inAdMode) THEN
       smallNo = 1.0D-20
      ELSE
       smallNo = 1.0D-20
      ENDIF
#endif

      DO j=1-Oly,sNy+Oly
       uT(1-Olx,j)=0.
       uT(2-Olx,j)=0.
       uT(sNx+Olx,j)=0.
      ENDDO
      DO j=1-Oly,sNy+Oly
       DO i=1-Olx+2,sNx+Olx-1
        Rjp=(tracer(i+1,j)-tracer( i ,j))*maskLocW(i+1,j)
        Rj =(tracer( i ,j)-tracer(i-1,j))*maskLocW( i ,j)
        Rjm=(tracer(i-1,j)-tracer(i-2,j))*maskLocW(i-1,j)

        uCFL = uFld(i,j)
        IF ( calcCFL ) uCFL = ABS( uFld(i,j)*deltaTloc
     &                  *recip_dxC(i,j,bi,bj)*recip_deepFacC(k) )
        d0=(2.-uCFL)*(1.-uCFL)*oneSixth
        d1=(1.-uCFL*uCFL)*oneSixth
#ifdef OLD_DST3_FORMULATION
        IF ( ABS(Rj).LT.smallNo .OR.
     &       ABS(Rjm).LT.smallNo ) THEN
         thetaP=0.
         psiP=0.
        ELSE
         thetaP=(Rjm+smallNo)/(smallNo+Rj)
         psiP=d0+d1*thetaP
        ENDIF
        IF ( ABS(Rj).LT.smallNo .OR.
     &       ABS(Rjp).LT.smallNo ) THEN
         thetaM=0.
         psiM=0.
        ELSE
         thetaM=(Rjp+smallNo)/(smallNo+Rj)
         psiM=d0+d1*thetaM
        ENDIF
        uT(i,j)=
     &   0.5*(uTrans(i,j)+ABS(uTrans(i,j)))
     &      *( Tracer(i-1,j) + psiP*Rj )
     &  +0.5*(uTrans(i,j)-ABS(uTrans(i,j)))
     &      *( Tracer( i ,j) - psiM*Rj )
#else /* OLD_DST3_FORMULATION */
        uT(i,j)=
     &   0.5*(uTrans(i,j)+ABS(uTrans(i,j)))
     &      *( Tracer(i-1,j) + (d0*Rj+d1*Rjm) )
     &  +0.5*(uTrans(i,j)-ABS(uTrans(i,j)))
     &      *( Tracer( i ,j) - (d0*Rj+d1*Rjp) )
#endif /* OLD_DST3_FORMULATION */

       ENDDO
      ENDDO

      RETURN
      END
1	jmc	1.14	C $Header: /u/gcmpack/MITgcm/pkg/generic_advdiff/gad_dst3_adv_x.F,v 1.13 2008/02/29 01:30:59 mlosch Exp $
2	adcroft	1.2	C $Name: $
3	adcroft	1.1
4			#include "GAD_OPTIONS.h"
5
6	jmc	1.10	CBOP
7			C !ROUTINE: GAD_DST3_ADV_X
8
9			C !INTERFACE: ==========================================================
10	jmc	1.8	SUBROUTINE GAD_DST3_ADV_X(
11	jmc	1.12	I bi,bj,k, calcCFL, deltaTloc,
12	jmc	1.8	I uTrans, uFld,
13	jmc	1.4	I maskLocW, tracer,
14	adcroft	1.1	O uT,
15			I myThid )
16	jmc	1.10
17			C !DESCRIPTION:
18			C Calculates the area integrated zonal flux due to advection of a
19			C tracer using 3rd-order Direct Space and Time (DST-3) Advection Scheme
20
21			C !USES: ===============================================================
22	adcroft	1.1	IMPLICIT NONE
23
24			C == GLobal variables ==
25			#include "SIZE.h"
26	jmc	1.14	#ifdef OLD_DST3_FORMULATION
27	heimbach	1.5	#include "EEPARAMS.h"
28			#include "PARAMS.h"
29	jmc	1.14	#endif
30			#include "GRID.h"
31	adcroft	1.1	#include "GAD.h"
32
33			C == Routine arguments ==
34	jmc	1.10	C !INPUT PARAMETERS: ===================================================
35			C bi,bj :: tile indices
36			C k :: vertical level
37	jmc	1.12	C calcCFL :: =T: calculate CFL number ; =F: take uFld as CFL.
38	jmc	1.10	C deltaTloc :: local time-step (s)
39			C uTrans :: zonal volume transport
40	jmc	1.12	C uFld :: zonal flow / CFL number
41	jmc	1.10	C tracer :: tracer field
42			C myThid :: thread number
43	adcroft	1.1	INTEGER bi,bj,k
44	jmc	1.12	LOGICAL calcCFL
45	heimbach	1.5	_RL deltaTloc
46	adcroft	1.1	_RL uTrans(1-OLx:sNx+OLx,1-OLy:sNy+OLy)
47	jmc	1.8	_RL uFld (1-OLx:sNx+OLx,1-OLy:sNy+OLy)
48	jmc	1.4	_RS maskLocW(1-OLx:sNx+OLx,1-OLy:sNy+OLy)
49	adcroft	1.1	_RL tracer(1-OLx:sNx+OLx,1-OLy:sNy+OLy)
50	jmc	1.10	INTEGER myThid
51
52			C !OUTPUT PARAMETERS: ==================================================
53			C uT :: zonal advective flux
54	adcroft	1.1	_RL uT (1-OLx:sNx+OLx,1-OLy:sNy+OLy)
55
56			C == Local variables ==
57	jmc	1.10	C !LOCAL VARIABLES: ====================================================
58			C i,j :: loop indices
59	jmc	1.11	C uCFL :: Courant-Friedrich-Levy number
60	adcroft	1.1	INTEGER i,j
61	jmc	1.11	_RL Rjm,Rj,Rjp,uCFL,d0,d1
62	jmc	1.10	#ifdef OLD_DST3_FORMULATION
63	adcroft	1.2	_RL psiP,psiM,thetaP,thetaM
64	heimbach	1.5	_RL smallNo
65	jmc	1.6	c _RL Rjjm,Rjjp
66	heimbach	1.5
67			IF (inAdMode) THEN
68			smallNo = 1.0D-20
69			ELSE
70			smallNo = 1.0D-20
71			ENDIF
72	jmc	1.10	#endif
73	adcroft	1.1
74			DO j=1-Oly,sNy+Oly
75			uT(1-Olx,j)=0.
76			uT(2-Olx,j)=0.
77			uT(sNx+Olx,j)=0.
78	mlosch	1.13	ENDDO
79			DO j=1-Oly,sNy+Oly
80	adcroft	1.1	DO i=1-Olx+2,sNx+Olx-1
81	jmc	1.4	Rjp=(tracer(i+1,j)-tracer( i ,j))*maskLocW(i+1,j)
82			Rj =(tracer( i ,j)-tracer(i-1,j))*maskLocW( i ,j)
83			Rjm=(tracer(i-1,j)-tracer(i-2,j))*maskLocW(i-1,j)
84	adcroft	1.1
85	jmc	1.12	uCFL = uFld(i,j)
86			IF ( calcCFL ) uCFL = ABS( uFld(i,j)*deltaTloc
87	jmc	1.11	& recip_dxC(i,j,bi,bj)recip_deepFacC(k) )
88			d0=(2.-uCFL)(1.-uCFL)oneSixth
89			d1=(1.-uCFLuCFL)oneSixth
90	jmc	1.10	#ifdef OLD_DST3_FORMULATION
91	heimbach	1.5	IF ( ABS(Rj).LT.smallNo .OR.
92			& ABS(Rjm).LT.smallNo ) THEN
93			thetaP=0.
94			psiP=0.
95			ELSE
96			thetaP=(Rjm+smallNo)/(smallNo+Rj)
97			psiP=d0+d1*thetaP
98			ENDIF
99			IF ( ABS(Rj).LT.smallNo .OR.
100			& ABS(Rjp).LT.smallNo ) THEN
101			thetaM=0.
102			psiM=0.
103			ELSE
104			thetaM=(Rjp+smallNo)/(smallNo+Rj)
105			psiM=d0+d1*thetaM
106			ENDIF
107	adcroft	1.1	uT(i,j)=
108	jmc	1.10	& 0.5*(uTrans(i,j)+ABS(uTrans(i,j)))
109	adcroft	1.2	& ( Tracer(i-1,j) + psiPRj )
110	jmc	1.10	& +0.5*(uTrans(i,j)-ABS(uTrans(i,j)))
111	adcroft	1.2	& ( Tracer( i ,j) - psiMRj )
112	jmc	1.10	#else /* OLD_DST3_FORMULATION */
113			uT(i,j)=
114			& 0.5*(uTrans(i,j)+ABS(uTrans(i,j)))
115			& ( Tracer(i-1,j) + (d0Rj+d1*Rjm) )
116			& +0.5*(uTrans(i,j)-ABS(uTrans(i,j)))
117			& ( Tracer( i ,j) - (d0Rj+d1*Rjp) )
118			#endif /* OLD_DST3_FORMULATION */
119	adcroft	1.1
120			ENDDO
121			ENDDO
122
123			RETURN
124			END