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C $Header: /u/gcmpack/MITgcm_contrib/dgoldberg/streamice/streamice_driving_stress.F,v 1.2 2012/09/18 17:06:48 dgoldberg Exp $ |
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C $Name: $ |
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#include "STREAMICE_OPTIONS.h" |
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C---+----1----+----2----+----3----+----4----+----5----+----6----+----7-|--+----| |
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CBOP |
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SUBROUTINE STREAMICE_DRIVING_STRESS( myThid ) |
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! O taudx, |
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! O taudy ) |
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|
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C /============================================================\ |
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C | SUBROUTINE | |
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C | o | |
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C |============================================================| |
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C | | |
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C \============================================================/ |
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IMPLICIT NONE |
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|
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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 "STREAMICE.h" |
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#include "STREAMICE_CG.h" |
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|
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C !INPUT/OUTPUT ARGUMENTS |
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INTEGER myThid |
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! _RL taudx (1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy) |
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! _RL taudx (1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy) |
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|
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#ifdef ALLOW_STREAMICE |
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|
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C LOCAL VARIABLES |
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INTEGER i, j, bi, bj, k, l, |
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& Gi, Gj |
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LOGICAL at_west_bdry, at_east_bdry, |
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& at_north_bdry, at_south_bdry |
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_RL sx, sy, diffx, diffy, neu_val |
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|
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IF (myXGlobalLo.eq.1) at_west_bdry = .true. |
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IF (myYGlobalLo.eq.1) at_south_bdry = .true. |
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IF (myXGlobalLo-1+sNx*nSx.eq.Nx) |
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& at_east_bdry = .false. |
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IF (myYGlobalLo-1+sNy*nSy.eq.Ny) |
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& at_north_bdry = .false. |
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|
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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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taudx_SI(i,j,bi,bj) = 0. _d 0 |
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taudy_SI(i,j,bi,bj) = 0. _d 0 |
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ENDDO |
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ENDDO |
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ENDDO |
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ENDDO |
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|
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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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DO i=0,sNx+1 |
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DO j=0,sNy+1 |
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|
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diffx = 0. _d 0 |
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diffy = 0. _d 0 |
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sx = 0. _d 0 |
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sy = 0. _d 0 |
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|
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Gi = (myXGlobalLo-1)+(bi-1)*sNx+i |
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Gj = (myYGlobalLo-1)+(bj-1)*sNy+j |
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|
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IF (STREAMICE_hmask(i,j,bi,bj).eq.1.0) THEN |
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|
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! we are in an "active" cell |
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|
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IF (Gi.eq.1.AND..NOT.STREAMICE_EW_periodic) THEN |
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|
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! western boundary - only one sided possible |
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|
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IF (STREAMICE_hmask(i+1,j,bi,bj).eq.1.0) THEN |
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|
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! cell to east is active |
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|
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sx = (surf_el_streamice(i+1,j,bi,bj)- |
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& surf_el_streamice(i,j,bi,bj))/dxC(i+1,j,bi,bj) |
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ELSE |
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|
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! cell to east is empty |
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|
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sx = 0. _d 0 |
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ENDIF |
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|
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ELSEIF (Gi.eq.Nx.AND..NOT.STREAMICE_EW_periodic) THEN |
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|
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! eastern boundary - only one sided possible |
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|
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IF (STREAMICE_hmask(i-1,j,bi,bj).eq.1.0) THEN |
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|
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! cell to west is active |
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|
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sx = (surf_el_streamice(i,j,bi,bj)- |
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& surf_el_streamice(i-1,j,bi,bj))/dxC(i,j,bi,bj) |
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ELSE |
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|
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! cell to west is inactive |
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|
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sx = 0. _d 0 |
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ENDIF |
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|
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ELSE |
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|
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! interior (west-east) cell |
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|
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IF (STREAMICE_hmask(i+1,j,bi,bj).eq.1.0) THEN |
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|
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! cell to east is active |
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|
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diffx = diffx + dxC(i+1,j,bi,bj) |
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sx = surf_el_streamice(i+1,j,bi,bj) |
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ELSE |
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sx = surf_el_streamice(i,j,bi,bj) |
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ENDIF |
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IF (STREAMICE_hmask(i-1,j,bi,bj).eq.1.0) THEN |
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|
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! cell to west is active |
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|
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diffx = diffx + dxC(i,j,bi,bj) |
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sx = sx - surf_el_streamice(i-1,j,bi,bj) |
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ELSE |
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sx = sx - surf_el_streamice(i,j,bi,bj) |
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ENDIF |
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IF (diffx .gt. 0. _d 0) THEN |
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sx = sx / diffx |
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ELSE |
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sx = 0. _d 0 |
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ENDIF |
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|
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ENDIF |
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|
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|
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|
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IF (Gj.eq.1.AND..NOT.STREAMICE_NS_periodic) THEN |
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IF (STREAMICE_hmask(i,j+1,bi,bj).eq.1.0) THEN |
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sy = (surf_el_streamice(i,j+1,bi,bj)- |
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& surf_el_streamice(i,j,bi,bj))/dyC(i,j+1,bi,bj) |
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ELSE |
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sy = 0. _d 0 |
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ENDIF |
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ELSEIF (Gj.eq.Ny.AND..NOT.STREAMICE_NS_periodic) THEN |
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IF (STREAMICE_hmask(i,j-1,bi,bj).eq.1.0) THEN |
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sy = (surf_el_streamice(i,j,bi,bj)- |
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& surf_el_streamice(i,j-1,bi,bj))/dyC(i,j,bi,bj) |
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ELSE |
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sy = 0. _d 0 |
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ENDIF |
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ELSE |
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IF (STREAMICE_hmask(i,j+1,bi,bj).eq.1.0) THEN |
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|
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diffy = diffy + dyC(i,j+1,bi,bj) |
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sy = surf_el_streamice(i,j+1,bi,bj) |
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ELSE |
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sy = surf_el_streamice(i,j,bi,bj) |
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ENDIF |
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IF (STREAMICE_hmask(i,j-1,bi,bj).eq.1.0) THEN |
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diffy = diffy + dyC(i,j,bi,bj) |
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sy = sy - surf_el_streamice(i,j-1,bi,bj) |
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ELSE |
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sy = sy - surf_el_streamice(i,j,bi,bj) |
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ENDIF |
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IF (diffy .gt. 0. _d 0) THEN |
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sy = sy / diffy |
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ELSE |
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sy = 0. _d 0 |
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ENDIF |
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ENDIF |
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|
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DO k=0,1 |
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DO l=0,1 |
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IF (STREAMICE_umask(i+k,j+l,bi,bj).eq.1.0) THEN |
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taudx_SI(i+k,j+l,bi,bj) = taudx_SI(i+k,j+l,bi,bj) - |
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& 0.25 * streamice_density * gravity * |
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& (streamice_bg_surf_slope_x+sx) * |
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& H_streamice(i,j,bi,bj) * rA(i,j,bi,bj) |
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! & (streamice_bg_surf_slope_x) * |
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! & 1000. * rA(i,j,bi,bj) |
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taudy_SI(i+k,j+l,bi,bj) = taudy_SI(i+k,j+l,bi,bj) - |
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& 0.25 * streamice_density * gravity * |
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& (streamice_bg_surf_slope_y+sy) * |
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& H_streamice(i,j,bi,bj) * rA(i,j,bi,bj) |
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|
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ENDIF |
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ENDDO |
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ENDDO |
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|
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IF (float_frac_streamice(i,j,bi,bj) .eq. 1.0) then |
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#ifdef USE_ALT_RLOW |
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neu_val = .5 * gravity * |
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& (streamice_density * H_streamice (i,j,bi,bj) ** 2 - |
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& streamice_density_ocean_avg * R_low_si(i,j,bi,bj) ** 2) |
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#else |
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neu_val = .5 * gravity * |
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& (streamice_density * H_streamice (i,j,bi,bj) ** 2 - |
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& streamice_density_ocean_avg * R_low(i,j,bi,bj) ** 2 |
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#endif |
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ELSE |
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neu_val = .5 * gravity * |
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& (1-streamice_density/streamice_density_ocean_avg) * |
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& streamice_density * H_streamice(i,j,bi,bj) ** 2 |
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ENDIF |
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|
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IF ((STREAMICE_ufacemask(i,j,bi,bj) .eq. 2) |
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& .OR. (STREAMICE_hmask(i-1,j,bi,bj) .eq. 0) |
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& .OR. (STREAMICE_hmask(i-1,j,bi,bj) .eq. 2) ) THEN ! left face of the cell is at a stress boundary |
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! the depth-integrated longitudinal stress is equal to the difference of depth-integrated pressure on either side of the face |
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! on the ice side, it is rho g h^2 / 2 |
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! on the ocean side, it is rhow g (delta OD)^2 / 2 |
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! OD can be zero under the ice; but it is ASSUMED on the ice-free side of the face, topography elevation is not above the base of the |
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! ice in the current cell |
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|
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taudx_SI(i,j,bi,bj) = taudx_SI(i,j,bi,bj) - |
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& .5 * dyG(i,j,bi,bj) * neu_val ! note negative sign is due to direction of normal vector |
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taudx_SI(i,j+1,bi,bj) = taudx_SI(i,j+1,bi,bj) - |
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& .5 * dyG(i,j,bi,bj) * neu_val |
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ENDIF |
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|
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IF ((STREAMICE_ufacemask(i+1,j,bi,bj) .eq. 2) |
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& .OR. (STREAMICE_hmask(i+1,j,bi,bj) .eq. 0) |
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& .OR. (STREAMICE_hmask(i+1,j,bi,bj) .eq. 2) ) THEN |
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|
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taudx_SI(i+1,j,bi,bj) = taudx_SI(i+1,j,bi,bj) + |
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& .5 * dyG(i+1,j,bi,bj) * neu_val ! note negative sign is due to direction of normal vector |
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taudx_SI(i+1,j+1,bi,bj) = taudx_SI(i+1,j+1,bi,bj) + |
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& .5 * dyG(i+1,j,bi,bj) * neu_val |
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ENDIF |
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|
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IF ((STREAMICE_vfacemask(i,j,bi,bj) .eq. 2) |
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& .OR. (STREAMICE_hmask(i,j-1,bi,bj) .eq. 0) |
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& .OR. (STREAMICE_hmask(i,j-1,bi,bj) .eq. 2) ) THEN |
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|
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taudy_SI(i,j,bi,bj) = taudy_SI(i,j,bi,bj) - |
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& .5 * dxG(i,j,bi,bj) * neu_val ! note negative sign is due to direction of normal vector |
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taudy_SI(i+1,j,bi,bj) = taudy_SI(i+1,j,bi,bj) - |
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& .5 * dxG(i,j,bi,bj) * neu_val |
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ENDIF |
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|
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IF ((STREAMICE_vfacemask(i,j+1,bi,bj) .eq. 2) |
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& .OR. (STREAMICE_hmask(i,j+1,bi,bj) .eq. 0) |
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& .OR. (STREAMICE_hmask(i,j+1,bi,bj) .eq. 2) ) THEN |
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|
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taudy_SI(i,j+1,bi,bj) = taudy_SI(i,j+1,bi,bj) + |
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& .5 * dxG(i,j+1,bi,bj) * neu_val ! note negative sign is due to direction of normal vector |
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taudy_SI(i+1,j+1,bi,bj) = taudy_SI(i+1,j+1,bi,bj) + |
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& .5 * dxG(i,j+1,bi,bj) * neu_val |
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ENDIF |
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|
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ENDIF |
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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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RETURN |
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END |
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