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C $Header: /u/gcmpack/MITgcm/pkg/generic_advdiff/gad_biharm_x.F,v 1.3 2004/12/16 22:29:35 jmc Exp $ |
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C $Name: $ |
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|
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#include "GAD_OPTIONS.h" |
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|
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CBOP |
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C !ROUTINE: GAD_BIHARM_X |
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|
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C !INTERFACE: ========================================================== |
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SUBROUTINE GAD_BIHARM_X( |
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I bi,bj,k, |
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I xA,del2T,diffK4, |
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U dfx, |
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I myThid ) |
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|
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C !DESCRIPTION: |
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C Calculates the zonal flux due to bi-harmonic diffusion of a tracer. |
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C Routine takes the laplacian of the tracer as argument and calculates |
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C the zonal gradient: |
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C \begin{equation*} |
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C F^x_{diff} = \kappa_4 \partial_x \nabla^2 \theta |
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C \end{equation*} |
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|
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C !USES: =============================================================== |
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IMPLICIT NONE |
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#include "SIZE.h" |
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#include "GRID.h" |
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|
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C !INPUT PARAMETERS: =================================================== |
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C bi,bj :: tile indices |
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C k :: vertical level |
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C xA :: area of face at U points |
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C del2T :: Laplacian of tracer |
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C myThid :: thread number |
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INTEGER bi,bj,k |
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_RS xA (1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RL del2T(1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RL diffK4 |
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INTEGER myThid |
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|
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C !OUTPUT PARAMETERS: ================================================== |
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C dfx :: zonal diffusive flux |
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_RL dfx (1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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|
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C !LOCAL VARIABLES: ==================================================== |
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C i,j :: loop indices |
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INTEGER i,j |
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CEOP |
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|
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C Difference of zonal fluxes ... |
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DO j=1-Oly,sNy+Oly |
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c dfx(1-Olx,j) = 0. |
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DO i=1-Olx+1,sNx+Olx |
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c dfx(i,j) = diffK4*xA(i,j) |
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dfx(i,j) = dfx(i,j) + diffK4*xA(i,j) |
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& *_recip_dxC(i,j,bi,bj)*recip_deepFacC(k) |
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& *(del2T(i,j)-del2T(i-1,j)) |
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#ifdef COSINEMETH_III |
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& *sqCosFacU(j,bi,bj) |
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#else |
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& *cosFacU(j,bi,bj) |
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#endif |
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ENDDO |
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ENDDO |
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|
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RETURN |
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END |