model/src/grad_sigma.F

C $Header: /u/gcmpack/MITgcm/model/src/grad_sigma.F,v 1.7 2007/07/27 22:18:57 heimbach Exp $
C $Name:  $

#include "CPP_OPTIONS.h"

CBOP
C     !ROUTINE: GRAD_SIGMA
C     !INTERFACE:
      SUBROUTINE GRAD_SIGMA(
     I             bi, bj, iMin, iMax, jMin, jMax, K,
     I             rhoK, sigKm1, sigKp1,
     O             sigmaX, sigmaY, sigmaR,
     I             myThid )
C     !DESCRIPTION: \bv
C     *==========================================================*
C     | SUBROUTINE GRAD_SIGMA
C     | o Calculate isoneutral gradients
C     *==========================================================*
C     \ev

C     !USES:
      IMPLICIT NONE
C     == Global variables ==
#include "SIZE.h"
#include "GRID.h"
#include "EEPARAMS.h"
#include "PARAMS.h"

C     !INPUT/OUTPUT PARAMETERS:
C     == Routine arguments ==
C     rhoK       :: density at level k
C     sigKm1     :: upper level density computed at current pressure
C     sigKp1     :: lower level density computed at current pressure
C     sigmaX,Y,R :: iso-neutral gradient of density in 3 directions X,Y,R
      INTEGER bi,bj,iMin,iMax,jMin,jMax,K
      _RL rhoK(1-Olx:sNx+Olx,1-Oly:sNy+Oly)
      _RL sigKm1(1-Olx:sNx+Olx,1-Oly:sNy+Oly)
      _RL sigKp1(1-Olx:sNx+Olx,1-Oly:sNy+Oly)
      _RL sigmaX(1-Olx:sNx+Olx,1-Oly:sNy+Oly,Nr)
      _RL sigmaY(1-Olx:sNx+Olx,1-Oly:sNy+Oly,Nr)
      _RL sigmaR(1-Olx:sNx+Olx,1-Oly:sNy+Oly,Nr)
      INTEGER myThid

C     !LOCAL VARIABLES:
C     == Local variables ==
C     rhoLoc :: local copy of rhoK
      INTEGER i,j
      _RL rhoLoc(1-Olx:sNx+Olx,1-Oly:sNy+Oly)
CEOP

C-    safer to work on a local copy of rhoK (before a partial update)
      DO j=1-Oly,sNy+Oly
       DO i=1-Olx,sNx+Olx
        rhoLoc(i,j) = rhoK(i,j)
       ENDDO
      ENDDO

C-    Internal exchange for calculations in X
cph-exch2#ifndef ALLOW_AUTODIFF_TAMC
      IF ( useCubedSphereExchange ) THEN
        CALL FILL_CS_CORNER_TR_RL( .TRUE., .FALSE.,
     &                             rhoLoc, bi,bj, myThid )
      ENDIF
cph-exch2#endif
      DO j=1-Oly,sNy+Oly
       DO i=1-Olx+1,sNx+Olx
        sigmaX(i,j,k)=_maskW(i,j,k,bi,bj)
     &        *_recip_dxC(i,j,bi,bj)
     &        *(rhoLoc(i,j)-rhoLoc(i-1,j))
       ENDDO
      ENDDO

C-    Internal exchange for calculations in Y
cph-exch2#ifndef ALLOW_AUTODIFF_TAMC
      IF ( useCubedSphereExchange ) THEN
        CALL FILL_CS_CORNER_TR_RL(.FALSE., .FALSE.,
     &                             rhoLoc, bi,bj, myThid )
      ENDIF
cph-exch2#endif
      DO j=1-Oly+1,sNy+Oly
       DO i=1-Olx,sNx+Olx
        sigmaY(i,j,k)=_maskS(i,j,k,bi,bj)
     &        *_recip_dyC(i,j,bi,bj)
     &        *(rhoLoc(i,j)-rhoLoc(i,j-1))
       ENDDO
      ENDDO

      IF (K.EQ.1) THEN
       DO j=1-Oly,sNy+Oly
        DO i=1-Olx,sNx+Olx
         sigmaR(i,j,k)=0.
        ENDDO
       ENDDO
      ELSE
       DO j=1-Oly,sNy+Oly
        DO i=1-Olx,sNx+Olx
         sigmaR(i,j,k)= maskC(i,j,k,bi,bj)
     &                *recip_drC(k)*rkSign
     &                *(sigKp1(i,j)-sigKm1(i,j))
        ENDDO
       ENDDO
      ENDIF

      RETURN
      END
1	jmc	1.8	C $Header: /u/gcmpack/MITgcm/model/src/grad_sigma.F,v 1.7 2007/07/27 22:18:57 heimbach Exp $
2	cnh	1.3	C $Name: $
3	adcroft	1.1
4			#include "CPP_OPTIONS.h"
5
6	cnh	1.3	CBOP
7			C !ROUTINE: GRAD_SIGMA
8			C !INTERFACE:
9	adcroft	1.1	SUBROUTINE GRAD_SIGMA(
10			I bi, bj, iMin, iMax, jMin, jMax, K,
11			I rhoK, sigKm1, sigKp1,
12			O sigmaX, sigmaY, sigmaR,
13			I myThid )
14	cnh	1.3	C !DESCRIPTION: \bv
15			C ==========================================================
16	jmc	1.8	C \| SUBROUTINE GRAD_SIGMA
17			C \| o Calculate isoneutral gradients
18	cnh	1.3	C ==========================================================
19			C \ev
20
21			C !USES:
22	adcroft	1.1	IMPLICIT NONE
23			C == Global variables ==
24			#include "SIZE.h"
25			#include "GRID.h"
26			#include "EEPARAMS.h"
27			#include "PARAMS.h"
28
29	cnh	1.3	C !INPUT/OUTPUT PARAMETERS:
30	adcroft	1.1	C == Routine arguments ==
31	jmc	1.4	C rhoK :: density at level k
32			C sigKm1 :: upper level density computed at current pressure
33			C sigKp1 :: lower level density computed at current pressure
34			C sigmaX,Y,R :: iso-neutral gradient of density in 3 directions X,Y,R
35	adcroft	1.1	INTEGER bi,bj,iMin,iMax,jMin,jMax,K
36			_RL rhoK(1-Olx:sNx+Olx,1-Oly:sNy+Oly)
37			_RL sigKm1(1-Olx:sNx+Olx,1-Oly:sNy+Oly)
38			_RL sigKp1(1-Olx:sNx+Olx,1-Oly:sNy+Oly)
39			_RL sigmaX(1-Olx:sNx+Olx,1-Oly:sNy+Oly,Nr)
40			_RL sigmaY(1-Olx:sNx+Olx,1-Oly:sNy+Oly,Nr)
41			_RL sigmaR(1-Olx:sNx+Olx,1-Oly:sNy+Oly,Nr)
42			INTEGER myThid
43
44	cnh	1.3	C !LOCAL VARIABLES:
45	adcroft	1.1	C == Local variables ==
46	jmc	1.4	C rhoLoc :: local copy of rhoK
47	adcroft	1.1	INTEGER i,j
48	jmc	1.4	_RL rhoLoc(1-Olx:sNx+Olx,1-Oly:sNy+Oly)
49	cnh	1.3	CEOP
50	adcroft	1.1
51	jmc	1.4	C- safer to work on a local copy of rhoK (before a partial update)
52			DO j=1-Oly,sNy+Oly
53			DO i=1-Olx,sNx+Olx
54			rhoLoc(i,j) = rhoK(i,j)
55			ENDDO
56			ENDDO
57
58			C- Internal exchange for calculations in X
59	heimbach	1.7	cph-exch2#ifndef ALLOW_AUTODIFF_TAMC
60	jmc	1.4	IF ( useCubedSphereExchange ) THEN
61	jmc	1.8	CALL FILL_CS_CORNER_TR_RL( .TRUE., .FALSE.,
62			& rhoLoc, bi,bj, myThid )
63	jmc	1.4	ENDIF
64	heimbach	1.7	cph-exch2#endif
65	adcroft	1.1	DO j=1-Oly,sNy+Oly
66			DO i=1-Olx+1,sNx+Olx
67			sigmaX(i,j,k)=_maskW(i,j,k,bi,bj)
68			& *_recip_dxC(i,j,bi,bj)
69	jmc	1.4	& *(rhoLoc(i,j)-rhoLoc(i-1,j))
70	adcroft	1.1	ENDDO
71			ENDDO
72
73	jmc	1.4	C- Internal exchange for calculations in Y
74	heimbach	1.7	cph-exch2#ifndef ALLOW_AUTODIFF_TAMC
75	jmc	1.4	IF ( useCubedSphereExchange ) THEN
76	jmc	1.8	CALL FILL_CS_CORNER_TR_RL(.FALSE., .FALSE.,
77			& rhoLoc, bi,bj, myThid )
78	jmc	1.4	ENDIF
79	heimbach	1.7	cph-exch2#endif
80	adcroft	1.1	DO j=1-Oly+1,sNy+Oly
81			DO i=1-Olx,sNx+Olx
82			sigmaY(i,j,k)=_maskS(i,j,k,bi,bj)
83			& *_recip_dyC(i,j,bi,bj)
84	jmc	1.4	& *(rhoLoc(i,j)-rhoLoc(i,j-1))
85	adcroft	1.1	ENDDO
86			ENDDO
87
88	jmc	1.4	IF (K.EQ.1) THEN
89			DO j=1-Oly,sNy+Oly
90			DO i=1-Olx,sNx+Olx
91	adcroft	1.1	sigmaR(i,j,k)=0.
92	jmc	1.4	ENDDO
93	adcroft	1.1	ENDDO
94	jmc	1.4	ELSE
95			DO j=1-Oly,sNy+Oly
96			DO i=1-Olx,sNx+Olx
97			sigmaR(i,j,k)= maskC(i,j,k,bi,bj)
98	jmc	1.6	& recip_drC(k)rkSign
99			& *(sigKp1(i,j)-sigKm1(i,j))
100	jmc	1.4	ENDDO
101			ENDDO
102			ENDIF
103	adcroft	1.1
104			RETURN
105			END