Changeset 913 for trunk/NEMO/LIM_SRC_3/limdyn.F90

Timestamp:

2008-04-29T14:40:00+02:00 (16 years ago)

Author:

ctlod

Message:

Manage wind stress at the sea-ice (LIM 3.0)/ocean interface in a proper way, see ticket: #128

File:

• trunk/NEMO/LIM_SRC_3/limdyn.F90 (modified) (3 diffs)

trunk/NEMO/LIM_SRC_3/limdyn.F90

@@ -18 +18 @@
    USE ice
    USE par_ice
+   USE sbc_oce         ! Surface boundary condition: ocean fields
    USE sbc_ice         ! Surface boundary condition: ice fields
    USE ice_oce
@@ -66 +67 @@
       !!------------------------------------------------------------------------------------
       !! * Local variables
-      INTEGER ::   ji, jj, jl, ja    ! dummy loop indices
-      INTEGER :: i_j1, i_jpj         ! Starting/ending j-indices for rheology
-
-      REAL(wp) ::   &
-         ztairx, ztairy,          &  ! tempory scalars
-         zsang , zmod,            &
-         ztglx , ztgly ,          &
-         zt11, zt12, zt21, zt22 , &
-         zustm,                   &
-         zsfrldmx2, zsfrldmy2,    &
-         zu_ice, zv_ice, ztair2
-
-      REAL(wp),DIMENSION(jpj) ::   &
-           zind,                     &  ! i-averaged indicator of sea-ice
-           zmsk                         ! i-averaged of tmask
+      INTEGER  ::   ji, jj, jl, ja    ! dummy loop indices
+      INTEGER  ::   i_j1, i_jpj       ! Starting/ending j-indices for rheology
+      REAL(wp) ::   zcoef             ! temporary scalar
+      REAL(wp), DIMENSION(jpj)     ::   zind           ! i-averaged indicator of sea-ice
+      REAL(wp), DIMENSION(jpj)     ::   zmsk           ! i-averaged of tmask
+      REAL(wp), DIMENSION(jpi,jpj) ::   zu_io, zv_io   ! ice-ocean velocity
       !!---------------------------------------------------------------------
 
@@ -159 +151 @@
 
          ! computation of friction velocity
+         ! --------------------------------
+         ! ice-ocean velocity at U & V-points (u_ice vi_ice at U- & V-points ; ssu_m, ssv_m at U- & V-points)
+         zu_io(:,:) = u_ice(:,:) - ssu_m(:,:)
+         zv_io(:,:) = v_ice(:,:) - ssv_m(:,:)
+         ! frictional velocity at T-point
+         DO jj = 2, jpjm1 
+            DO ji = fs_2, fs_jpim1   ! vector opt.
+               ust2s(ji,jj) = 0.5 * cw                                                          &
+                  &         * (  zu_io(ji,jj) * zu_io(ji,jj) + zu_io(ji-1,jj) * zu_io(ji-1,jj)   &
+                  &            + zv_io(ji,jj) * zv_io(ji,jj) + zv_io(ji,jj-1) * zv_io(ji,jj-1)   ) * tms(ji,jj)
+            END DO
+         END DO
+         !
+      ELSE      ! no ice dynamics : transmit directly the atmospheric stress to the ocean
+         !
+         zcoef = SQRT( 0.5 ) / rau0
          DO jj = 2, jpjm1
-            DO ji = fs_2, fs_jpim1
-
-               zu_ice   = u_ice(ji,jj) - u_oce(ji,jj)
-               zt11  = rhoco * zu_ice * zu_ice
-
-               zu_ice   = u_ice(ji-1,jj) - u_oce(ji-1,jj)
-               zt12  = rhoco * zu_ice * zu_ice
-
-               zv_ice   = v_ice(ji,jj) - v_oce(ji,jj)
-               zt21  = rhoco * zv_ice * zv_ice
-
-               zv_ice   = v_ice(ji,jj-1) - v_oce(ji,jj-1)
-               zt22  = rhoco * zv_ice * zv_ice
-               ztair2 = ( ( utaui_ice(ji,jj) + utaui_ice(ji-1,jj) ) / 2. )**2 + &
-                        ( ( vtaui_ice(ji,jj) + vtaui_ice(ji,jj-1) ) / 2. )**2
-
-               ! should not be weighted
-               zustm =  ( at_i(ji,jj)       ) * 0.5 * ( zt11 + zt12 + zt21 + zt22 )        &
-                  &  +  ( 1.0 - at_i(ji,jj) ) * SQRT( ztair2 )
-
-               ust2s(ji,jj) = ( zustm / rau0 ) * tms(ji,jj)
-
+            DO ji = fs_2, fs_jpim1   ! vector opt.
+               ust2s(ji,jj) = zcoef * tms(ji,jj) * SQRT(  utau(ji,jj) * utau(ji,jj) + utau(ji-1,jj) * utau(ji-1,jj)   &
+                  &                                     + vtau(ji,jj) * vtau(ji,jj) + vtau(ji,jj-1) * vtau(ji,jj-1) )
             END DO
          END DO
-
-       ELSE      ! If no ice dynamics  
-                    
-               ! virer ca (key_lim_cp1)
-          DO jj = 2, jpjm1
-             DO ji = fs_2, fs_jpim1
-                ztair2 = ( ( utaui_ice(ji,jj) + utaui_ice(ji-1,jj) ) / 2. )**2 + &
-                         ( ( vtaui_ice(ji,jj) + vtaui_ice(ji,jj-1) ) / 2. )**2
-                zustm        = SQRT( ztair2  )
-
-                ust2s(ji,jj) = ( zustm / rau0 ) * tms(ji,jj)
-            END DO
-         END DO
-
+         !
       ENDIF