natl_12/code/gad_biharm_y.F

C $Header: /u/gcmpack/MITgcm_contrib/natl_12/code/gad_biharm_y.F,v 1.1 2003/08/05 21:22:43 cnh Exp $
C $Name:  $

#include "GAD_OPTIONS.h"

CBOP
C !ROUTINE: GAD_BIHARM_Y

C !INTERFACE: ==========================================================
      SUBROUTINE GAD_BIHARM_Y( 
     I           bi,bj,k,
     I           yA,del2T,diffK4,
     O           dfy,
     I           myThid )

C !DESCRIPTION:
C Calculates the meridional flux due to bi-harmonic diffusion of a tracer.
C Routine takes the laplacian of the tracer as argument and calculates
C the meridional gradient:
C \begin{equation*}
C F^y_{diff} = \kappa_4 \partial_y \nabla^2 \theta
C \end{equation*}

C !USES: ===============================================================
      IMPLICIT NONE
#include "SIZE.h"
#include "GRID.h"

C !INPUT PARAMETERS: ===================================================
C  bi,bj                :: tile indices
C  k                    :: vertical level
C  yA                   :: area of face at V points
C  del2T                :: Laplacian of tracer
C  myThid               :: thread number
      INTEGER bi,bj,k
      _RS yA   (1-OLx:sNx+OLx,1-OLy:sNy+OLy)
      _RL del2T(1-OLx:sNx+OLx,1-OLy:sNy+OLy)
      _RL diffK4
      INTEGER myThid

C !OUTPUT PARAMETERS: ==================================================
C  dfy                  :: meridional diffusive flux
      _RL dfy  (1-OLx:sNx+OLx,1-OLy:sNy+OLy)

C !LOCAL VARIABLES: ====================================================
C  i,j                  :: loop indices
      INTEGER i,j
      _RS gridScalingK4
CEOP

C     Difference of meridional fluxes ...
      DO i=1-Olx,sNx+Olx
       dfy(i,1-Oly) = 0.
      ENDDO
      DO j=1-Oly+1,sNy+Oly
       DO i=1-Olx,sNx+Olx
         gridScalingK4 = (_dyC(i,j,bi,bj)**4. _d 0)/(5000. _d 0**4. _d 0)
         dfy(i,j) = diffK4
     &    *gridScalingK4
     &    *yA(i,j)
     &    *(del2T(i,j)-del2T(i,j-1))*_recip_dyC(i,j,bi,bj)
#ifdef ISOTROPIC_COS_SCALING
#ifdef COSINEMETH_III
     &    *sqCosFacV(j,bi,bj)
#else
     &    *CosFacV(j,bi,bj)
#endif
#endif
       ENDDO
      ENDDO

      RETURN
      END
1	C $Header: /u/gcmpack/MITgcm_contrib/natl_12/code/gad_biharm_y.F,v 1.1 2003/08/05 21:22:43 cnh Exp $
2	C $Name: $
3
4	#include "GAD_OPTIONS.h"
5
6	CBOP
7	C !ROUTINE: GAD_BIHARM_Y
8
9	C !INTERFACE: ==========================================================
10	SUBROUTINE GAD_BIHARM_Y(
11	I bi,bj,k,
12	I yA,del2T,diffK4,
13	O dfy,
14	I myThid )
15
16	C !DESCRIPTION:
17	C Calculates the meridional flux due to bi-harmonic diffusion of a tracer.
18	C Routine takes the laplacian of the tracer as argument and calculates
19	C the meridional gradient:
20	C \begin{equation*}
21	C F^y_{diff} = \kappa_4 \partial_y \nabla^2 \theta
22	C \end{equation*}
23
24	C !USES: ===============================================================
25	IMPLICIT NONE
26	#include "SIZE.h"
27	#include "GRID.h"
28
29	C !INPUT PARAMETERS: ===================================================
30	C bi,bj :: tile indices
31	C k :: vertical level
32	C yA :: area of face at V points
33	C del2T :: Laplacian of tracer
34	C myThid :: thread number
35	INTEGER bi,bj,k
36	_RS yA (1-OLx:sNx+OLx,1-OLy:sNy+OLy)
37	_RL del2T(1-OLx:sNx+OLx,1-OLy:sNy+OLy)
38	_RL diffK4
39	INTEGER myThid
40
41	C !OUTPUT PARAMETERS: ==================================================
42	C dfy :: meridional diffusive flux
43	_RL dfy (1-OLx:sNx+OLx,1-OLy:sNy+OLy)
44
45	C !LOCAL VARIABLES: ====================================================
46	C i,j :: loop indices
47	INTEGER i,j
48	_RS gridScalingK4
49	CEOP
50
51	C Difference of meridional fluxes ...
52	DO i=1-Olx,sNx+Olx
53	dfy(i,1-Oly) = 0.
54	ENDDO
55	DO j=1-Oly+1,sNy+Oly
56	DO i=1-Olx,sNx+Olx
57	gridScalingK4 = (_dyC(i,j,bi,bj)4. _d 0)/(5000. _d 04. _d 0)
58	dfy(i,j) = diffK4
59	& *gridScalingK4
60	& *yA(i,j)
61	& (del2T(i,j)-del2T(i,j-1))_recip_dyC(i,j,bi,bj)
62	#ifdef ISOTROPIC_COS_SCALING
63	#ifdef COSINEMETH_III
64	& *sqCosFacV(j,bi,bj)
65	#else
66	& *CosFacV(j,bi,bj)
67	#endif
68	#endif
69	ENDDO
70	ENDDO
71
72	RETURN
73	END