Changeset 1505 for trunk/NEMO

Timestamp:

2009-07-20T17:36:58+02:00 (15 years ago)

Author:

rblod

Message:

Correct dynspg_exp for variable volume case, see ticket #479

File:

• trunk/NEMO/OPA_SRC/DYN/dynspg_exp.F90 (modified) (3 diffs)

trunk/NEMO/OPA_SRC/DYN/dynspg_exp.F90

@@ -4 +4 @@
    !! Ocean dynamics:  surface pressure gradient trend
    !!======================================================================
-   !! History :  9.0  !  2005-11  (V. Garnier, G. Madec, L. Bessieres) Original code
+   !! History :  2.0  !  2005-11  (V. Garnier, G. Madec, L. Bessieres) Original code
+   !!            3.2  !  2009-06  (G. Madec, M. Leclair, R. Benshila) introduce sshwzv module
    !!----------------------------------------------------------------------
 #if defined key_dynspg_exp   ||   defined key_esopa
    !!----------------------------------------------------------------------
-   !!   'key_dynspg_exp'           free sfce cst vol. without filter nor ts
+   !!   'key_dynspg_exp'                              explicit free surface
    !!----------------------------------------------------------------------
    !!   dyn_spg_exp  : update the momentum trend with the surface 
@@ -49 +50 @@
       !!
       !! ** Purpose :   Compute the now trend due to the surface pressure
-      !!      gradient in case of explicit free surface formulation and 
-      !!      add it to the general trend of momentum equation. Compute
-      !!      the free surface.
+      !!              gradient in case of explicit free surface formulation and 
+      !!              add it to the general trend of momentum equation.
       !!
-      !! ** Method  :   Explicit free surface formulation. The surface pressure
-      !!      gradient is given by:
-      !!         spgu = 1/rau0 d/dx(ps) =  g/e1u di( sshn )
-      !!         spgv = 1/rau0 d/dy(ps) =  g/e2v dj( sshn )
-      !!      -1- Compute the now surface pressure gradient
-      !!      -2- Add it to the general trend
+      !! ** Method  :   Explicit free surface formulation. Add to the general
+      !!              momentum trend the surface pressure gradient :
+      !!                      (ua,va) = (ua,va) + (spgu,spgv)
+      !!              where spgu = -1/rau0 d/dx(ps) = -g/e1u di( sshn )
+      !!                    spgv = -1/rau0 d/dy(ps) = -g/e2v dj( sshn )
       !!
-      !! ** Action : - Update (ua,va) with the surf. pressure gradient trend
+      !! ** Action :   (ua,va)   trend of horizontal velocity increased by 
+      !!                         the surf. pressure gradient trend
       !!---------------------------------------------------------------------
       INTEGER, INTENT( in )  ::   kt         ! ocean time-step index
@@ -71 +71 @@
          IF(lwp) WRITE(numout,*) 'dyn_spg_exp : surface pressure gradient trend'
          IF(lwp) WRITE(numout,*) '~~~~~~~~~~~   (explicit free surface)'
-
-         ! set to zero free surface specific arrays
-         spgu(:,:) = 0.e0                     ! surface pressure gradient (i-direction)
-         spgv(:,:) = 0.e0                     ! surface pressure gradient (j-direction)
+         !
+         spgu(:,:) = 0.e0   ;   spgv(:,:) = 0.e0
+         !
+         IF( lk_vvl .AND. lwp ) WRITE(numout,*) '              lk_vvl=T : spg is included in dynhpg'
       ENDIF
 
-      ! read or estimate sea surface height and vertically integrated velocities
-      IF( lk_obc )   CALL obc_dta_bt( kt, 0 )
 
-      ! Surface pressure gradient (now)
-      DO jj = 2, jpjm1
-         DO ji = fs_2, fs_jpim1   ! vector opt.
-            spgu(ji,jj) = - grav * ( sshn(ji+1,jj) - sshn(ji,jj) ) / e1u(ji,jj)
-            spgv(ji,jj) = - grav * ( sshn(ji,jj+1) - sshn(ji,jj) ) / e2v(ji,jj)
-         END DO
-      END DO
+!!gm bug ??  Rachid we have to discuss of the call below. I don't understand why it is here and not in ssh_wzv
+      IF( lk_obc )   CALL obc_dta_bt( kt, 0 )      ! OBC: read or estimate ssh and vertically integrated velocities
+!!gm
 
-      ! Add the surface pressure trend to the general trend
-      DO jk = 1, jpkm1
-         DO jj = 2, jpjm1
+      IF( .NOT. lk_vvl ) THEN          !* fixed volume : add the surface pressure gradient trend
+         !
+         DO jj = 2, jpjm1                    ! now surface pressure gradient
             DO ji = fs_2, fs_jpim1   ! vector opt.
-               ua(ji,jj,jk) = ua(ji,jj,jk) + spgu(ji,jj)
-               va(ji,jj,jk) = va(ji,jj,jk) + spgv(ji,jj)
+               spgu(ji,jj) = - grav * ( sshn(ji+1,jj) - sshn(ji,jj) ) / e1u(ji,jj)
+               spgv(ji,jj) = - grav * ( sshn(ji,jj+1) - sshn(ji,jj) ) / e2v(ji,jj)
+            END DO 
+         END DO 
+         DO jk = 1, jpkm1                    ! Add it to the general trend
+            DO jj = 2, jpjm1
+               DO ji = fs_2, fs_jpim1   ! vector opt.
+                  ua(ji,jj,jk) = ua(ji,jj,jk) + spgu(ji,jj)
+                  va(ji,jj,jk) = va(ji,jj,jk) + spgv(ji,jj)
+               END DO
             END DO
          END DO
-      END DO
-
+         !
+      ENDIF
+      !
    END SUBROUTINE dyn_spg_exp