Changeset 519 for trunk/NEMO/OPA_SRC

Timestamp:

2006-10-11T15:49:05+02:00 (18 years ago)

Author:

opalod

Message:

nemo_v1_update_74 : CT : - add comments for the UBS scheme

• syntax correction
• remove the use of eddy velocity in the calculation of poleward transport since it is already included into the normal velocity
• remove the save of the trend associated to the BBL advective velocity since it is already included into the normal velocity

Location:

trunk/NEMO/OPA_SRC

Files:

• DIA/diaptr.F90 (modified) (4 diffs)
• TRA/traadv.F90 (modified) (1 diff)
• TRA/traadv_ubs.F90 (modified) (1 diff)
• TRA/trabbl_adv.h90 (modified) (2 diffs)

trunk/NEMO/OPA_SRC/DIA/diaptr.F90

@@ -241 +241 @@
          v_atl , v_ipc,                    &
          vt_atl, vt_pac, vt_ind,           &
-         vs_atl, vs_pac, vs_ind,           &
-         zv_eiv
+         vs_atl, vs_pac, vs_ind             
       INTEGER ::  inum       ! temporary logical unit
       !!----------------------------------------------------------------------
@@ -252 +251 @@
          zggram    = 1.e-6
    
-# if defined key_diaeiv
-         zv_eiv(:,:,:) = v_eiv(:,:,:)
-# else
-         zv_eiv(:,:,:) = 0.e0
-# endif
-
          ! "zonal" mean temperature and salinity at V-points
          tn_jk(:,:) = ptr_vtjk( tn(:,:,:) ) * surf_jk_r(:,:)
@@ -279 +272 @@
                DO ji = 1, jpi
                   ! basin separated velocity
-                  v_atl(ji,jj,:) = (vn(ji,jj,:)+zv_eiv(ji,jj,:))*abasin(ji,jj)
-                  v_ipc(ji,jj,:) = (vn(ji,jj,:)+zv_eiv(ji,jj,:))*(pbasin(ji,jj)+ibasin(ji,jj))
+                  v_atl(ji,jj,:) = vn(ji,jj,:)*abasin(ji,jj)
+                  v_ipc(ji,jj,:) = vn(ji,jj,:)*(pbasin(ji,jj)+ibasin(ji,jj))
 
                   ! basin separated T times V on T points
-                  vt_ind(ji,jj,:) = tn(ji,jj,:) *                                 &
-                     &              ( (vn    (ji,jj,:) + vn    (ji,jj-1,:))*0.5   &
-                     &              + (zv_eiv(ji,jj,:) + zv_eiv(ji,jj-1,:))*0.5 ) 
+                  vt_ind(ji,jj,:) = tn(ji,jj,:) * ( vn(ji,jj,:) + vn(ji,jj-1,:) )*0.5
                   vt_atl(ji,jj,:) = vt_ind(ji,jj,:) * abasin(ji,jj)
                   vt_pac(ji,jj,:) = vt_ind(ji,jj,:) * pbasin(ji,jj)
@@ -291 +282 @@
 
                   ! basin separated S times V on T points
-                  vs_ind(ji,jj,:) = sn(ji,jj,:) *                                 &
-                     &              ( (vn    (ji,jj,:) + vn    (ji,jj-1,:))*0.5   &
-                     &              + (zv_eiv(ji,jj,:) + zv_eiv(ji,jj-1,:))*0.5 ) 
+                  vs_ind(ji,jj,:) = sn(ji,jj,:) * ( vn(ji,jj,:) + vn(ji,jj-1,:) )*0.5
                   vs_atl(ji,jj,:) = vs_ind(ji,jj,:) * abasin(ji,jj)
                   vs_pac(ji,jj,:) = vs_ind(ji,jj,:) * pbasin(ji,jj)

trunk/NEMO/OPA_SRC/TRA/traadv.F90

@@ -97 +97 @@
       CASE (-1 )                                                     ! esopa: test all possibility with control print
          ;             CALL tra_adv_cen2    ( kt, zun, zvn, zwn )
-         ;             CALL prt_ctl( tab3d_1=ta, clinfo1=' ldf0 - Ta: ', mask1=tmask,               &
+         ;             CALL prt_ctl( tab3d_1=ta, clinfo1=' adv0 - Ta: ', mask1=tmask,               &
             &                        tab3d_2=sa, clinfo2=       ' Sa: ', mask2=tmask, clinfo3='tra' )
          ;             CALL tra_adv_cen2_jki( kt, zun, zvn, zwn )
-         ;             CALL prt_ctl( tab3d_1=ta, clinfo1=' ldf1 - Ta: ', mask1=tmask,               &
+         ;             CALL prt_ctl( tab3d_1=ta, clinfo1=' adv1 - Ta: ', mask1=tmask,               &
             &                        tab3d_2=sa, clinfo2=       ' Sa: ', mask2=tmask, clinfo3='tra' )
          ;             CALL tra_adv_tvd     ( kt, zun, zvn, zwn )
-         ;             CALL prt_ctl( tab3d_1=ta, clinfo1=' ldf2 - Ta: ', mask1=tmask,               &
+         ;             CALL prt_ctl( tab3d_1=ta, clinfo1=' adv2 - Ta: ', mask1=tmask,               &
             &                        tab3d_2=sa, clinfo2=       ' Sa: ', mask2=tmask, clinfo3='tra' )
          ;             CALL tra_adv_muscl   ( kt, zun, zvn, zwn )
-         ;             CALL prt_ctl( tab3d_1=ta, clinfo1=' ldf3 - Ta: ', mask1=tmask,               &
+         ;             CALL prt_ctl( tab3d_1=ta, clinfo1=' adv3 - Ta: ', mask1=tmask,               &
             &                        tab3d_2=sa, clinfo2=       ' Sa: ', mask2=tmask, clinfo3='tra' )
          ;             CALL tra_adv_muscl2  ( kt, zun, zvn, zwn )
-         ;             CALL prt_ctl( tab3d_1=ta, clinfo1=' ldf4 - Ta: ', mask1=tmask,               &
+         ;             CALL prt_ctl( tab3d_1=ta, clinfo1=' adv4 - Ta: ', mask1=tmask,               &
             &                        tab3d_2=sa, clinfo2=       ' Sa: ', mask2=tmask, clinfo3='tra' )
          ;             CALL tra_adv_ubs     ( kt, zun, zvn, zwn )

trunk/NEMO/OPA_SRC/TRA/traadv_ubs.F90

@@ -47 +47 @@
       !!      and add it to the general trend of passive tracer equations.
       !!
-      !! ** Method  :   ???
+      !! ** Method  :   The upstream biased third (UBS) is order scheme based 
+      !!      on an upstream-biased parabolic interpolation (Shchepetkin and McWilliams 2005)
+      !!      It is only used in the horizontal direction.
+      !!      For example the i-component of the advective fluxes are given by :
+      !!                !  e1u e3u un ( mi(Tn) - zltu(i  ) )   if un(i) >= 0
+      !!          zwx = !  or 
+      !!                !  e1u e3u un ( mi(Tn) - zltu(i+1) )   if un(i) < 0
+      !!      where zltu is the second derivative of the before temperature field:
+      !!          zltu = 1/e3t di[ e2u e3u / e1u di[Tb] ]
+      !!      This results in a dissipatively dominant (i.e. hyper-diffusive) 
+      !!      truncation error. The overall performance of the advection scheme 
+      !!      is similar to that reported in (Farrow and Stevens, 1995). 
+      !!      For stability reasons, the first term of the fluxes which corresponds
+      !!      to a second order centered scheme is evaluated using the now velocity 
+      !!      (centered in time) while the second term which is the diffusive part 
+      !!      of the scheme, is evaluated using the before velocity (forward in time). 
+      !!      Note that UBS is not positive. Do not use it on passive tracers.
+      !!      On the vertical, the advection is evaluated using a TVD scheme, as
+      !!      the UBS have been found to be too diffusive.
       !!
       !! ** Action : - update (ta,sa) with the now advective tracer trends
+      !!
+      !! Reference : Shchepetkin, A. F., J. C. McWilliams, 2005, Ocean Modelling, 9, 347-404. 
+      !!             Farrow, D.E., Stevens, D.P., 1995, J. Phys. Ocean. 25, 1731Ð1741. 
       !!----------------------------------------------------------------------
       USE oce, ONLY :   zwx => ua   ! use ua as workspace

trunk/NEMO/OPA_SRC/TRA/trabbl_adv.h90

@@ -93 +93 @@
       !!----------------------------------------------------------------------
 
-
       IF( kt == nit000 )   CALL tra_bbl_init    ! initialization at first time-step
-
-      IF( l_trdtra )   THEN      ! Save ta and sa trends
-         ztrdt(:,:,:) = ta(:,:,:) 
-         ztrds(:,:,:) = sa(:,:,:) 
-      ENDIF
 
       ! 1. 2D fields of bottom temperature and salinity, and bottom slope
@@ -342 +336 @@
       END DO
 
-      ! save the trends for diagnostic
-      ! BBL lateral advection tracers trends
-      IF( l_trdtra )   THEN
-         ztrdt(:,:,:) = ta(:,:,:) - ztrdt(:,:,:)
-         ztrds(:,:,:) = sa(:,:,:) - ztrds(:,:,:)
-         CALL trd_mod(ztrdt, ztrds, jptra_trd_bbl, 'TRA', kt)
-      ENDIF
-
       IF(ln_ctl)   CALL prt_ctl( tab3d_1=ta, clinfo1=' bbl  - Ta: ', mask1=tmask,   &
          &                       tab3d_2=sa, clinfo2=       ' Sa: ', mask2=tmask, clinfo3='tra' )