Changeset 15394 for NEMO/trunk/src/TOP/TRP/trcsbc.F90

Timestamp:

2021-10-18T12:55:29+02:00 (3 years ago)

Author:

cetlod

Message:

trunk : bugfix in passive tracer surface boundary condition trend of flux, see ticket #2733

File:

• NEMO/trunk/src/TOP/TRP/trcsbc.F90 (modified) (4 diffs)

NEMO/trunk/src/TOP/TRP/trcsbc.F90

@@ -51 +51 @@
       !!            The surface freshwater flux modify the ocean volume
       !!         and thus the concentration of a tracer as :
-      !!            tr(Krhs) = tr(Krhs) + emp * tr(Kmm) / e3t_   for k=1
-      !!         where emp, the surface freshwater budget (evaporation minus
-      !!         precipitation ) given in kg/m2/s is divided
-      !!         by 1035 kg/m3 (density of ocean water) to obtain m/s.
+      !!            tr(Krhs) = tr(Krhs) + emp * tr(Kmm) / e3t_ + fmmflx * tri / e3t   for k=1
+      !!          - tr(Kmm) , the concentration of tracer in the ocean
+      !!          - tri, the concentration of tracer in the sea-ice
+      !!          - emp, the surface freshwater budget (evaporation minus precipitation + fmmflx)
+      !!            given in kg/m2/s is divided by 1035 kg/m3 (density of ocean water) to obtain m/s.
+      !!          - fmmflx, the flux asscociated to freezing-melting of sea-ice 
+      !!            In linear free surface case (ln_linssh=T), the volume of the
+      !!            ocean does not change with the water exchanges at the (air+ice)-sea
       !!
       !! ** Action  : - Update the 1st level of tr(:,:,:,:,Krhs) with the trend associated
@@ -66 +70 @@
       INTEGER  ::   ji, jj, jn                      ! dummy loop indices
       REAL(wp) ::   zse3t, zrtrn, zfact     ! local scalars
-      REAL(wp) ::   zftra, zdtra, ztfx, ztra   !   -      -
+      REAL(wp) ::   zdtra          !   -      -
       CHARACTER (len=22) :: charout
-      REAL(wp), DIMENSION(jpi,jpj)   ::   zsfx
       REAL(wp), ALLOCATABLE, DIMENSION(:,:,:) ::   ztrtrd
       !!---------------------------------------------------------------------
@@ -106 +109 @@
       ENDIF
 
-      ! Coupling online : river runoff is added to the horizontal divergence (hdiv) in the subroutine sbc_rnf_div 
-      ! one only consider the concentration/dilution effect due to evaporation minus precipitation + freezing/melting of sea-ice
-      ! Coupling offline : runoff are in emp which contains E-P-R
-      !
-      IF( .NOT.ln_linssh ) THEN  ! online coupling with vvl
-         zsfx(:,:) = 0._wp
-      ELSE                                      ! online coupling free surface or offline with free surface
-         zsfx(:,:) = emp(:,:)
-      ENDIF
-
       ! 0. initialization
       SELECT CASE ( nn_ice_tr )
 
-      CASE ( -1 ) ! No tracers in sea ice (null concentration in sea ice)
-         !
-         DO jn = 1, jptra
-            DO_2D( 0, 0, 0, 1 )
-               sbc_trc(ji,jj,jn) = zsfx(ji,jj) * r1_rho0 * ptr(ji,jj,1,jn,Kmm)
-            END_2D
-         END DO
-         !
-      CASE ( 0 )  ! Same concentration in sea ice and in the ocean
-         !
-         DO jn = 1, jptra
-            DO_2D( 0, 0, 0, 1 )
-               sbc_trc(ji,jj,jn) = ( zsfx(ji,jj) + fmmflx(ji,jj) ) * r1_rho0 * ptr(ji,jj,1,jn,Kmm)
-            END_2D
-         END DO
+      CASE ( -1 ) ! ! No tracers in sea ice ( trc_i = 0 )
+         !
+         DO jn = 1, jptra
+            DO_2D( 0, 0, 0, 1 )
+               sbc_trc(ji,jj,jn) = 0._wp
+            END_2D
+         END DO
+         !
+         IF( ln_linssh ) THEN  !* linear free surface  
+            DO jn = 1, jptra
+               DO_2D( 0, 0, 0, 1 )
+                  sbc_trc(ji,jj,jn) = sbc_trc(ji,jj,jn) + r1_rho0 * emp(ji,jj) * ptr(ji,jj,1,jn,Kmm) !==>> add concentration/dilution effect due to constant volume cell
+               END_2D
+            END DO
+         ENDIF
+         !
+      CASE ( 0 )  ! Same concentration in sea ice and in the ocean ( trc_i = ptr(...,Kmm)  )
+         !
+         DO jn = 1, jptra
+            DO_2D( 0, 0, 0, 1 )
+               sbc_trc(ji,jj,jn) = - fmmflx(ji,jj) * r1_rho0 * ptr(ji,jj,1,jn,Kmm)
+            END_2D
+         END DO
+         !
+         IF( ln_linssh ) THEN  !* linear free surface  
+            DO jn = 1, jptra
+               DO_2D( 0, 0, 0, 1 )
+                  sbc_trc(ji,jj,jn) = sbc_trc(ji,jj,jn) + r1_rho0 * emp(ji,jj) * ptr(ji,jj,1,jn,Kmm) !==>> add concentration/dilution effect due to constant volume cell
+               END_2D
+            END DO
+         ENDIF
          !
       CASE ( 1 )  ! Specific treatment of sea ice fluxes with an imposed concentration in sea ice 
@@ -139 +148 @@
          DO jn = 1, jptra
             DO_2D( 0, 0, 0, 1 )
-               zse3t = 1. / e3t(ji,jj,1,Kmm)
-               ! tracer flux at the ice/ocean interface (tracer/m2/s)
-               zftra = - trc_i(ji,jj,jn) * fmmflx(ji,jj) ! uptake of tracer in the sea ice
-               !                                         ! only used in the levitating sea ice case
-               ! tracer flux only       : add concentration dilution term in net tracer flux, no F-M in volume flux
-               ! tracer and mass fluxes : no concentration dilution term in net tracer flux, F-M term in volume flux
-               ztfx  = zftra                        ! net tracer flux
-               !
-               zdtra = r1_rho0 * ( ztfx + ( zsfx(ji,jj) + fmmflx(ji,jj) ) * ptr(ji,jj,1,jn,Kmm) ) 
-               IF ( zdtra < 0. ) THEN
-                  zdtra  = MAX(zdtra, -ptr(ji,jj,1,jn,Kmm) * e3t(ji,jj,1,Kmm) / rDt_trc )   ! avoid negative concentrations to arise
-               ENDIF
-               sbc_trc(ji,jj,jn) =  zdtra 
-            END_2D
-         END DO
+               sbc_trc(ji,jj,jn) = - fmmflx(ji,jj) * r1_rho0 * trc_i(ji,jj,jn)
+            END_2D
+         END DO
+         !
+         IF( ln_linssh ) THEN  !* linear free surface  
+            DO jn = 1, jptra
+               DO_2D( 0, 0, 0, 1 )
+                  sbc_trc(ji,jj,jn) = sbc_trc(ji,jj,jn) + r1_rho0 * emp(ji,jj) * ptr(ji,jj,1,jn,Kmm) !==>> add concentration/dilution effect due to constant volume cell
+               END_2D
+            END DO
+         ENDIF
+         !
+         DO jn = 1, jptra
+            DO_2D( 0, 0, 0, 1 )
+               zse3t = rDt_trc / e3t(ji,jj,1,Kmm)
+               zdtra = ptr(ji,jj,1,jn,Kmm) + sbc_trc(ji,jj,jn) * zse3t 
+               IF( zdtra < 0. ) sbc_trc(ji,jj,jn) = MAX( zdtra, -ptr(ji,jj,1,jn,Kmm) / zse3t  ) ! avoid negative concentration that can occurs if trc_i > ptr 
+            END_2D
+         END DO
+         !                             
       END SELECT
       !