Changeset 12926 for NEMO/releases/r4.0/r4.0-HEAD/src/OCE/SBC/sbcblk.F90

Timestamp:

2020-05-14T16:10:40+02:00 (3 years ago)

Author:

smasson

Message:

r4.0-HEAD: avoid pollution of atm-ice stress at coastal points, see #2465

File:

• NEMO/releases/r4.0/r4.0-HEAD/src/OCE/SBC/sbcblk.F90 (modified) (2 diffs)

NEMO/releases/r4.0/r4.0-HEAD/src/OCE/SBC/sbcblk.F90

@@ -706 +706 @@
       REAL(wp) ::   zwndi_f , zwndj_f, zwnorm_f   ! relative wind module and components at F-point
       REAL(wp) ::   zwndi_t , zwndj_t             ! relative wind components at T-point
+      REAL(wp) ::   zztmp1  , zztmp2              ! temporary values
       REAL(wp), DIMENSION(jpi,jpj) ::   zrhoa     ! transfer coefficient for momentum      (tau)
       !!---------------------------------------------------------------------
@@ -744 +745 @@
       zrhoa (:,:) =  rho_air(sf(jp_tair)%fnow(:,:,1), sf(jp_humi)%fnow(:,:,1), sf(jp_slp)%fnow(:,:,1))
 
-      !!gm brutal....
-      utau_ice  (:,:) = 0._wp
-      vtau_ice  (:,:) = 0._wp
-      !!gm end
-
       ! ------------------------------------------------------------ !
       !    Wind stress relative to the moving ice ( U10m - U_ice )   !
       ! ------------------------------------------------------------ !
-      ! C-grid ice dynamics :   U & V-points (same as ocean)
-      DO jj = 2, jpjm1
+      zztmp1 = rn_vfac * 0.5_wp
+      DO jj = 2, jpj    ! at T point
+         DO ji = 2, jpi
+            zztmp2 = zrhoa(ji,jj) * Cd_atm(ji,jj) * wndm_ice(ji,jj)
+            utau_ice(ji,jj) = zztmp2 * ( sf(jp_wndi)%fnow(ji,jj,1) - zztmp1 * ( u_ice(ji-1,jj  ) + u_ice(ji,jj) ) )
+            vtau_ice(ji,jj) = zztmp2 * ( sf(jp_wndj)%fnow(ji,jj,1) - zztmp1 * ( v_ice(ji  ,jj-1) + v_ice(ji,jj) ) )
+         END DO
+      END DO
+      !
+      DO jj = 2, jpjm1  ! U & V-points (same as ocean).
          DO ji = fs_2, fs_jpim1   ! vect. opt.
-            utau_ice(ji,jj) = 0.5 * zrhoa(ji,jj) * Cd_atm(ji,jj) * ( wndm_ice(ji+1,jj  ) + wndm_ice(ji,jj) )            &
-               &          * ( 0.5 * (sf(jp_wndi)%fnow(ji+1,jj,1) + sf(jp_wndi)%fnow(ji,jj,1) ) - rn_vfac * u_ice(ji,jj) )
-            vtau_ice(ji,jj) = 0.5 * zrhoa(ji,jj) * Cd_atm(ji,jj) * ( wndm_ice(ji,jj+1  ) + wndm_ice(ji,jj) )            &
-               &          * ( 0.5 * (sf(jp_wndj)%fnow(ji,jj+1,1) + sf(jp_wndj)%fnow(ji,jj,1) ) - rn_vfac * v_ice(ji,jj) )
+            ! take care of the land-sea mask to avoid "pollution" of coastal stress. p[uv]taui used in frazil and  rheology 
+            zztmp1 = 0.5_wp * ( 2. - umask(ji,jj,1) ) * MAX( tmask(ji,jj,1),tmask(ji+1,jj  ,1) )
+            zztmp2 = 0.5_wp * ( 2. - vmask(ji,jj,1) ) * MAX( tmask(ji,jj,1),tmask(ji  ,jj+1,1) )
+            utau_ice(ji,jj) = zztmp1 * ( utau_ice(ji,jj) + utau_ice(ji+1,jj  ) )
+            vtau_ice(ji,jj) = zztmp2 * ( vtau_ice(ji,jj) + vtau_ice(ji  ,jj+1) )
          END DO
       END DO