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C $Header: /u/gcmpack/MITgcm/pkg/shelfice/shelfice_v_drag.F,v 1.1 2006/02/07 11:45:21 mlosch Exp $ |
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C $Name: $ |
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|
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#include "SHELFICE_OPTIONS.h" |
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#include "MOM_COMMON_OPTIONS.h" |
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|
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CBOP |
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C !ROUTINE: SHELFICE_V_DRAG |
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|
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C !INTERFACE: ========================================================== |
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SUBROUTINE SHELFICE_V_DRAG( |
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I bi,bj,k, |
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I vFld, KE, KappaRV, |
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O vDragTerms, |
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I myThid) |
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|
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C !DESCRIPTION: |
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C Calculates the drag due to friction and the no-slip condition at the |
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C bottom of the shelf-ice (in analogy to bottom drag) |
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C \begin{equation*} |
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C G^v_{drag} = - ( r_b + C_D |v| + \frac{2}{\Delta r_c} ) v |
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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 "EEPARAMS.h" |
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#include "PARAMS.h" |
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#include "GRID.h" |
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#include "SHELFICE.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 vFld :: meridional flow |
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C KE :: Kinetic energy |
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C KappaRV :: vertical viscosity |
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C myThid :: thread number |
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INTEGER bi,bj,k |
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_RL vFld(1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RL KE(1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RL KappaRV(1-OLx:sNx+OLx,1-OLy:sNy+OLy,Nr) |
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_RL viscFac |
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INTEGER myThid |
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|
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C !OUTPUT PARAMETERS: ================================================== |
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C vDragTerms :: drag term |
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_RL vDragTerms(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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C Kp1 :: =k+1 for k<Nr, =Nr for k>=Nr |
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INTEGER I,J,kUp,kUpC,kTop |
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_RL rdrckp1,maskUp |
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CEOP |
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|
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C- No-slip BCs impose a drag at bottom |
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IF ( usingZCoords ) THEN |
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kTop = 1 |
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kUp = k |
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kUpC = kUp |
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ELSE |
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kTop = Nr |
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kUp = min(k+1,kTop) |
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kUpC = kUp |
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ENDIF |
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rdrckp1=recip_drC(kUpC) |
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viscFac=0. |
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IF (no_slip_shelfice) viscFac=1. |
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IF (k.EQ.kUp) rdrckp1=recip_drF(k) |
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DO j=1-Oly+1,sNy+Oly-1 |
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DO i=1-Olx,sNx+Olx-1 |
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maskUp=_maskS(i,j,kUp,bi,bj) |
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CML IF (k.EQ.kTop) maskUp=0. |
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vDragTerms(i,j)= |
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& -_recip_hFacS(i,j,k,bi,bj)*recip_drF(k) |
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& *( |
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& 2.*KappaRV(i,j,kUpC)*rdrckp1*viscFac |
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& + bottomDragLinear |
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& )*(1.-maskUp)*vFld(i,j) |
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IF ( (KE(i,j)+KE(i,j-1)) .NE. 0. ) THEN |
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vDragTerms(i,j)=vDragTerms(i,j) |
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& -_recip_hFacS(i,j,k,bi,bj)*recip_drF(k) |
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& *bottomDragQuadratic*sqrt(KE(i,j)+KE(i,j-1)) |
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& *(1.-maskUp)*vFld(i,j) |
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ENDIF |
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ENDDO |
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ENDDO |
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|
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CML#ifdef ALLOW_DIAGNOSTICS |
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CML IF (useDiagnostics) THEN |
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CML CALL DIAGNOSTICS_FILL(vDragTerms,'VBotDrag',k,1,2,bi,bj,myThid) |
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CML ENDIF |
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CML#endif /* ALLOW_DIAGNOSTICS */ |
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|
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RETURN |
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END |