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C $Header: /u/gcmpack/MITgcm/pkg/seaice/seaice_get_dynforcing.F,v 1.14 2012/11/09 22:15:18 heimbach Exp $ |
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C $Name: $ |
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|
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#include "SEAICE_OPTIONS.h" |
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|
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CBOP |
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C !ROUTINE: SEAICE_SOLVE4TEMP |
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C !INTERFACE: |
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SUBROUTINE SEAICE_GET_DYNFORCING( |
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I uIce, vIce, |
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O taux, tauy, |
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I myTime, myIter, myThid ) |
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C !DESCRIPTION: \bv |
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C *==========================================================* |
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C | SUBROUTINE SEAICE_GET_DYNFORCING |
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C | compute surface stress from atmopheric forcing fields |
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C *==========================================================* |
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C | started by Martin Losch, April 2007 |
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C *==========================================================* |
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C \ev |
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|
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C !USES: |
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IMPLICIT NONE |
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C === Global variables === |
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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 "FFIELDS.h" |
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#include "DYNVARS.h" |
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#include "SEAICE_SIZE.h" |
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#include "SEAICE_PARAMS.h" |
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#ifdef ALLOW_EXF |
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# include "EXF_OPTIONS.h" |
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# include "EXF_FIELDS.h" |
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# include "EXF_PARAM.h" |
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#endif |
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|
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C !INPUT/OUTPUT PARAMETERS: |
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C uIce (inp) :: zonal ice velocity (input) |
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C vIce (inp) :: meridional ice velocity (input) |
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C taux (out) :: zonal wind stress over ice at U point |
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C tauy (out) :: meridional wind stress over ice at V point |
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C myTime (inp) :: current time in simulation |
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C myIter (inp) :: iteration number in simulation |
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C myThid (inp) :: my Thread Id. number |
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_RL uIce (1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy) |
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_RL vIce (1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy) |
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_RL taux (1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy) |
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_RL tauy (1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy) |
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_RL myTime |
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INTEGER myIter |
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INTEGER myThid |
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CEOP |
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|
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#ifdef SEAICE_CGRID |
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C !LOCAL VARIABLES: |
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C i,j,bi,bj :: Loop counters |
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C ks :: vertical index of surface layer |
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INTEGER bi, bj, i, j |
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INTEGER ks |
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_RL COSWIN |
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_RS SINWIN |
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_RL U1, V1, AAA |
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C CDAIR :: local wind stress coefficient (used twice) |
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C oceTauX :: wind-stress over open-ocean (on Arakawa A-grid), X direction |
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C oceTauY :: wind-stress over open-ocean (on Arakawa A-grid), Y direction |
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_RL CDAIR (1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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#ifndef SEAICE_EXTERNAL_FLUXES |
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_RL oceTauX (1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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_RL oceTauY (1-OLx:sNx+OLx,1-OLy:sNy+OLy) |
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#endif |
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|
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C-- surface level |
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ks = 1 |
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C-- introduce turning angle (default is zero) |
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SINWIN=SIN(SEAICE_airTurnAngle*deg2rad) |
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COSWIN=COS(SEAICE_airTurnAngle*deg2rad) |
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|
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C-- NOW SET UP FORCING FIELDS |
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|
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#ifdef SEAICE_EXTERNAL_FLUXES |
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IF (useAtmWind) THEN |
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#endif |
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C-- Wind stress is computed on center of C-grid cell |
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C and interpolated to U and V points later |
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DO bj=myByLo(myThid),myByHi(myThid) |
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DO bi=myBxLo(myThid),myBxHi(myThid) |
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|
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#ifndef SEAICE_EXTERNAL_FLUXES |
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C-- First compute wind-stress over open ocean: this will results in |
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C over-writing fu and fv that were computed or read-in by pkg/exf. |
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DO j=1-Oly,sNy+Oly |
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DO i=1-Olx,sNx+Olx |
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U1=UWIND(i,j,bi,bj) |
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V1=VWIND(i,j,bi,bj) |
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AAA=U1**2+V1**2 |
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IF ( AAA .LE. SEAICE_EPS_SQ ) THEN |
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AAA=SEAICE_EPS |
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ELSE |
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AAA=SQRT(AAA) |
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ENDIF |
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CDAIR(i,j)=SEAICE_rhoAir*OCEAN_drag |
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& *(2.70 _d 0+0.142 _d 0*AAA+0.0764 _d 0*AAA*AAA) |
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oceTauX(i,j)=CDAIR(i,j)* |
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& (COSWIN*U1-SIGN(SINWIN, _fCori(i,j,bi,bj))*V1) |
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oceTauY(i,j)=CDAIR(i,j)* |
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& (SIGN(SINWIN, _fCori(i,j,bi,bj))*U1+COSWIN*V1) |
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ENDDO |
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ENDDO |
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C-- Interpolate wind stress over open ocean (N/m^2) |
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C from A-grid to U and V points of C-grid |
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DO j=1-Oly+1,sNy+Oly |
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DO i=1-Olx+1,sNx+Olx |
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fu(i,j,bi,bj) = 0.5 _d 0*( oceTauX(i,j) + oceTauX(i-1,j) ) |
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& *_maskW(i,j,ks,bi,bj) |
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fv(i,j,bi,bj) = 0.5 _d 0*( oceTauY(i,j) + oceTauY(i,j-1) ) |
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& *_maskS(i,j,ks,bi,bj) |
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ENDDO |
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ENDDO |
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#endif /* ndef SEAICE_EXTERNAL_FLUXES */ |
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|
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C-- Now compute ice surface stress |
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IF (useRelativeWind) THEN |
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DO j=1-Oly,sNy+Oly-1 |
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DO i=1-Olx,sNx+Olx-1 |
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U1=UWIND(i,j,bi,bj) |
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& + 0.5 _d 0 * (uVel(i,j,ks,bi,bj)+uVel(i+1,j,ks,bi,bj)) |
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& - 0.5 _d 0 * (uIce(i,j,bi,bj)+uIce(i+1,j,bi,bj)) |
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V1=VWIND(i,j,bi,bj) |
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& + 0.5 _d 0 * (vVel(i,j,ks,bi,bj)+vVel(i,j+1,ks,bi,bj)) |
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& - 0.5 _d 0 * (vIce(i,j,bi,bj)+vIce(i,j+1,bi,bj)) |
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AAA=U1**2+V1**2 |
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IF ( AAA .LE. SEAICE_EPS_SQ ) THEN |
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AAA=SEAICE_EPS |
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ELSE |
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AAA=SQRT(AAA) |
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ENDIF |
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IF ( yC(i,j,bi,bj) .LT. ZERO ) THEN |
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CDAIR(i,j) = SEAICE_rhoAir*SEAICE_drag_south*AAA |
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ELSE |
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CDAIR(i,j) = SEAICE_rhoAir*SEAICE_drag*AAA |
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ENDIF |
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ENDDO |
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ENDDO |
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ELSE |
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DO j=1-Oly,sNy+Oly |
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DO i=1-Olx,sNx+Olx |
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U1=UWIND(i,j,bi,bj) |
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V1=VWIND(i,j,bi,bj) |
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AAA=U1**2+V1**2 |
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IF ( AAA .LE. SEAICE_EPS_SQ ) THEN |
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AAA=SEAICE_EPS |
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ELSE |
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AAA=SQRT(AAA) |
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ENDIF |
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IF ( yC(i,j,bi,bj) .LT. ZERO ) THEN |
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CDAIR(i,j) = SEAICE_rhoAir*SEAICE_drag_south*AAA |
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ELSE |
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CDAIR(i,j) = SEAICE_rhoAir*SEAICE_drag*AAA |
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ENDIF |
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ENDDO |
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ENDDO |
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ENDIF |
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IF (useRelativeWind) THEN |
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DO j=1-Oly+1,sNy+Oly-1 |
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DO i=1-Olx+1,sNx+Olx-1 |
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C interpolate to U points |
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taux(i,j,bi,bj)= 0.5 _d 0 * |
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& ( CDAIR(i,j)*(COSWIN* |
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& (uWind(i,j,bi,bj) |
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& +0.5 _d 0*(uVel(i,j,ks,bi,bj)+uVel(i+1,j,ks,bi,bj)) |
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& -0.5 _d 0*(uIce(i,j,bi,bj)+uIce(i+1,j,bi,bj))) |
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& -SIGN(SINWIN, _fCori(i,j,bi,bj))* |
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& (vWind(i,j,bi,bj) |
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& +0.5 _d 0*(vVel(i,j,ks,bi,bj)+vVel(i,j+1,ks,bi,bj)) |
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& -0.5 _d 0*(vIce(i,j,bi,bj)+vIce(i,j+1,bi,bj)))) |
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& +CDAIR(i-1,j)*(COSWIN* |
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& (uWind(i-1,j,bi,bj) |
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& +0.5 _d 0*(uVel(i-1,j,ks,bi,bj)+uVel(i,j,ks,bi,bj)) |
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& -0.5 _d 0*(uIce(i-1,j,bi,bj)+uIce(i,j,bi,bj))) |
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& -SIGN(SINWIN, _fCori(i-1,j,bi,bj))* |
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& (vWind(i-1,j,bi,bj) |
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& +0.5 _d 0*(vVel(i-1,j,ks,bi,bj)+vVel(i-1,j+1,ks,bi,bj)) |
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& -0.5 _d 0*(vIce(i-1,j,bi,bj)+vIce(i-1,j+1,bi,bj)))) |
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& )*_maskW(i,j,ks,bi,bj) |
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C interpolate to V points |
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tauy(i,j,bi,bj)= 0.5 _d 0 * |
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& ( CDAIR(i,j)*(SIGN(SINWIN, _fCori(i,j,bi,bj))* |
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& (uWind(i,j,bi,bj) |
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& +0.5 _d 0*(uVel(i,j,ks,bi,bj)+uVel(i+1,j,ks,bi,bj)) |
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& -0.5 _d 0*(uIce(i,j,bi,bj)+uIce(i+1,j,bi,bj))) |
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& +COSWIN* |
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& (vWind(i,j,bi,bj) |
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& +0.5 _d 0*(vVel(i,j,ks,bi,bj)+vVel(i,j+1,ks,bi,bj)) |
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& -0.5 _d 0*(vIce(i,j,bi,bj)+vIce(i,j+1,bi,bj)))) |
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& +CDAIR(i,j-1)*(SIGN(SINWIN, _fCori(i,j-1,bi,bj))* |
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& (uWind(i,j-1,bi,bj) |
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& +0.5 _d 0*(uVel(i,j-1,ks,bi,bj)+uVel(i+1,j-1,ks,bi,bj)) |
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& -0.5 _d 0*(uIce(i,j-1,bi,bj)+uIce(i+1,j-1,bi,bj))) |
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& +COSWIN* |
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& (vWind(i,j-1,bi,bj) |
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& +0.5 _d 0*(vVel(i,j-1,ks,bi,bj)+vVel(i,j,ks,bi,bj)) |
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& -0.5 _d 0*(vIce(i,j-1,bi,bj)+vIce(i,j,bi,bj)))) |
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& )*_maskS(i,j,ks,bi,bj) |
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ENDDO |
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ENDDO |
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ELSE |
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DO j=1-Oly+1,sNy+Oly |
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DO i=1-Olx+1,sNx+Olx |
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C interpolate to U points |
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taux(i,j,bi,bj)=0.5 _d 0 * |
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& ( CDAIR(i ,j)*( |
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& COSWIN *uWind(i ,j,bi,bj) |
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& -SIGN(SINWIN, _fCori(i ,j,bi,bj))*vWind(i ,j,bi,bj) ) |
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& + CDAIR(i-1,j)*( |
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& COSWIN *uWind(i-1,j,bi,bj) |
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& -SIGN(SINWIN, _fCori(i-1,j,bi,bj))*vWind(i-1,j,bi,bj) ) |
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& )*_maskW(i,j,ks,bi,bj) |
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C interpolate to V points |
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tauy(i,j,bi,bj)=0.5 _d 0 * |
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& ( CDAIR(i,j )*( |
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& SIGN(SINWIN, _fCori(i,j ,bi,bj))*uWind(i,j ,bi,bj) |
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& +COSWIN*vWind(i,j ,bi,bj) ) |
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& + CDAIR(i,j-1)*( |
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& SIGN(SINWIN, _fCori(i,j-1,bi,bj))*uWind(i,j-1,bi,bj) |
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& +COSWIN*vWind(i,j-1,bi,bj) ) |
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& )*_maskS(i,j,ks,bi,bj) |
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ENDDO |
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ENDDO |
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ENDIF |
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|
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ENDDO |
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ENDDO |
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|
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#ifdef SEAICE_EXTERNAL_FLUXES |
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ELSE |
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C-- Wind stress is available on U and V points, copy it to seaice variables. |
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DO bj=myByLo(myThid),myByHi(myThid) |
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DO bi=myBxLo(myThid),myBxHi(myThid) |
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DO j=1-Oly,sNy+Oly |
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DO i=1-Olx,sNx+Olx |
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C now ice surface stress |
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IF ( yC(i,j,bi,bj) .LT. ZERO ) THEN |
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CDAIR(i,j) = SEAICE_drag_south/OCEAN_drag |
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ELSE |
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CDAIR(i,j) = SEAICE_drag /OCEAN_drag |
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ENDIF |
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taux(i,j,bi,bj) = CDAIR(i,j)*fu(i,j,bi,bj) |
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& *_maskW(i,j,ks,bi,bj) |
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tauy(i,j,bi,bj) = CDAIR(i,j)*fv(i,j,bi,bj) |
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& *_maskS(i,j,ks,bi,bj) |
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ENDDO |
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ENDDO |
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ENDDO |
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ENDDO |
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ENDIF |
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#endif /* SEAICE_EXTERNAL_FLUXES */ |
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#endif /* SEAICE_CGRID */ |
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|
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RETURN |
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END |
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