Index: branches/2014/dev_r4650_UKMO14.5_SST_BIAS_CORRECTION/NEMOGCM/NEMO/TOP_SRC/PISCES/P4Z/p4zsink.F90
===================================================================
--- branches/2014/dev_r4650_UKMO14.5_SST_BIAS_CORRECTION/NEMOGCM/NEMO/TOP_SRC/PISCES/P4Z/p4zsink.F90	(revision 4750)
+++ branches/2014/dev_r4650_UKMO14.5_SST_BIAS_CORRECTION/NEMOGCM/NEMO/TOP_SRC/PISCES/P4Z/p4zsink.F90	(revision 5965)
@@ -41,5 +41,5 @@
 #endif
 
-   INTEGER  :: iksed  = 10
+   INTEGER  :: ik100
 
 #if  defined key_kriest
@@ -79,5 +79,5 @@
    !!----------------------------------------------------------------------
 
-   SUBROUTINE p4z_sink ( kt, jnt )
+   SUBROUTINE p4z_sink ( kt, knt )
       !!---------------------------------------------------------------------
       !!                     ***  ROUTINE p4z_sink  ***
@@ -88,5 +88,5 @@
       !! ** Method  : - ???
       !!---------------------------------------------------------------------
-      INTEGER, INTENT(in) :: kt, jnt
+      INTEGER, INTENT(in) :: kt, knt
       INTEGER  ::   ji, jj, jk, jit
       INTEGER  ::   iiter1, iiter2
@@ -94,7 +94,7 @@
       REAL(wp) ::   zagg , zaggfe, zaggdoc, zaggdoc2, zaggdoc3
       REAL(wp) ::   zfact, zwsmax, zmax, zstep
-      REAL(wp) ::   zrfact2
-      INTEGER  ::   ik1
       CHARACTER (len=25) :: charout
+      REAL(wp), POINTER, DIMENSION(:,:,:) :: zw3d
+      REAL(wp), POINTER, DIMENSION(:,:  ) :: zw2d
       !!---------------------------------------------------------------------
       !
@@ -199,15 +199,15 @@
                zfact = zstep * xdiss(ji,jj,jk)
                !  Part I : Coagulation dependent on turbulence
-               zagg1 = 25.9  * zfact * trn(ji,jj,jk,jppoc) * trn(ji,jj,jk,jppoc)
-               zagg2 = 4452. * zfact * trn(ji,jj,jk,jppoc) * trn(ji,jj,jk,jpgoc)
+               zagg1 = 25.9  * zfact * trb(ji,jj,jk,jppoc) * trb(ji,jj,jk,jppoc)
+               zagg2 = 4452. * zfact * trb(ji,jj,jk,jppoc) * trb(ji,jj,jk,jpgoc)
 
                ! Part II : Differential settling
 
                !  Aggregation of small into large particles
-               zagg3 =  47.1 * zstep * trn(ji,jj,jk,jppoc) * trn(ji,jj,jk,jpgoc)
-               zagg4 =  3.3  * zstep * trn(ji,jj,jk,jppoc) * trn(ji,jj,jk,jppoc)
+               zagg3 =  47.1 * zstep * trb(ji,jj,jk,jppoc) * trb(ji,jj,jk,jpgoc)
+               zagg4 =  3.3  * zstep * trb(ji,jj,jk,jppoc) * trb(ji,jj,jk,jppoc)
 
                zagg   = zagg1 + zagg2 + zagg3 + zagg4
-               zaggfe = zagg * trn(ji,jj,jk,jpsfe) / ( trn(ji,jj,jk,jppoc) + rtrn )
+               zaggfe = zagg * trb(ji,jj,jk,jpsfe) / ( trb(ji,jj,jk,jppoc) + rtrn )
 
                ! Aggregation of DOC to POC : 
@@ -215,12 +215,12 @@
                ! 2nd term is shear aggregation of DOC-POC
                ! 3rd term is differential settling of DOC-POC
-               zaggdoc  = ( ( 0.369 * 0.3 * trn(ji,jj,jk,jpdoc) + 102.4 * trn(ji,jj,jk,jppoc) ) * zfact       &
-               &            + 2.4 * zstep * trn(ji,jj,jk,jppoc) ) * 0.3 * trn(ji,jj,jk,jpdoc)
+               zaggdoc  = ( ( 0.369 * 0.3 * trb(ji,jj,jk,jpdoc) + 102.4 * trb(ji,jj,jk,jppoc) ) * zfact       &
+               &            + 2.4 * zstep * trb(ji,jj,jk,jppoc) ) * 0.3 * trb(ji,jj,jk,jpdoc)
                ! transfer of DOC to GOC : 
                ! 1st term is shear aggregation
                ! 2nd term is differential settling 
-               zaggdoc2 = ( 3.53E3 * zfact + 0.1 * zstep ) * trn(ji,jj,jk,jpgoc) * 0.3 * trn(ji,jj,jk,jpdoc)
+               zaggdoc2 = ( 3.53E3 * zfact + 0.1 * zstep ) * trb(ji,jj,jk,jpgoc) * 0.3 * trb(ji,jj,jk,jpdoc)
                ! tranfer of DOC to POC due to brownian motion
-               zaggdoc3 =  ( 5095. * trn(ji,jj,jk,jppoc) + 114. * 0.3 * trn(ji,jj,jk,jpdoc) ) *zstep * 0.3 * trn(ji,jj,jk,jpdoc)
+               zaggdoc3 =  ( 5095. * trb(ji,jj,jk,jppoc) + 114. * 0.3 * trb(ji,jj,jk,jpdoc) ) *zstep * 0.3 * trb(ji,jj,jk,jpdoc)
 
                !  Update the trends
@@ -235,24 +235,61 @@
       END DO
 
-     ! Total primary production per year
-     t_oce_co2_exp = t_oce_co2_exp + glob_sum( ( sinking(:,:,iksed+1) + sinking2(:,:,iksed+1) ) * e1e2t(:,:) * tmask(:,:,1) )
+
+     ! Total carbon export per year
+     IF( iom_use( "tcexp" ) .OR. ( ln_check_mass .AND. kt == nitend .AND. knt == nrdttrc )  )  &
+        &   t_oce_co2_exp = glob_sum( ( sinking(:,:,ik100) + sinking2(:,:,ik100) ) * e1e2t(:,:) * tmask(:,:,1) )
      !
-     IF( ln_diatrc ) THEN
-         zrfact2 = 1.e3 * rfact2r
-         ik1  = iksed + 1
-         IF( lk_iomput ) THEN
-           IF( jnt == nrdttrc ) THEN
-              CALL iom_put( "EPC100"  , ( sinking(:,:,ik1) + sinking2(:,:,ik1) ) * zrfact2 * tmask(:,:,1) ) ! Export of carbon at 100m
-              CALL iom_put( "EPFE100" , ( sinkfer(:,:,ik1) + sinkfer2(:,:,ik1) ) * zrfact2 * tmask(:,:,1) ) ! Export of iron at 100m
-              CALL iom_put( "EPCAL100",   sinkcal(:,:,ik1)                       * zrfact2 * tmask(:,:,1) ) ! Export of calcite  at 100m
-              CALL iom_put( "EPSI100" ,   sinksil(:,:,ik1)                       * zrfact2 * tmask(:,:,1) ) ! Export of biogenic silica at 100m
-           ENDIF
-         ELSE
-           trc2d(:,:,jp_pcs0_2d + 4) = sinking (:,:,ik1) * zrfact2 * tmask(:,:,1)
-           trc2d(:,:,jp_pcs0_2d + 5) = sinking2(:,:,ik1) * zrfact2 * tmask(:,:,1)
-           trc2d(:,:,jp_pcs0_2d + 6) = sinkfer (:,:,ik1) * zrfact2 * tmask(:,:,1)
-           trc2d(:,:,jp_pcs0_2d + 7) = sinkfer2(:,:,ik1) * zrfact2 * tmask(:,:,1)
-           trc2d(:,:,jp_pcs0_2d + 8) = sinksil (:,:,ik1) * zrfact2 * tmask(:,:,1)
-           trc2d(:,:,jp_pcs0_2d + 9) = sinkcal (:,:,ik1) * zrfact2 * tmask(:,:,1)
+     IF( lk_iomput ) THEN
+       IF( knt == nrdttrc ) THEN
+          CALL wrk_alloc( jpi, jpj,      zw2d )
+          CALL wrk_alloc( jpi, jpj, jpk, zw3d )
+          zfact = 1.e+3 * rfact2r  !  conversion from mol/l/kt to  mol/m3/s
+          !
+          IF( iom_use( "EPC100" ) )  THEN
+              zw2d(:,:) = ( sinking(:,:,ik100) + sinking2(:,:,ik100) ) * zfact * tmask(:,:,1) ! Export of carbon at 100m
+              CALL iom_put( "EPC100"  , zw2d )
+          ENDIF
+          IF( iom_use( "EPFE100" ) )  THEN
+              zw2d(:,:) = ( sinkfer(:,:,ik100) + sinkfer2(:,:,ik100) ) * zfact * tmask(:,:,1) ! Export of iron at 100m
+              CALL iom_put( "EPFE100"  , zw2d )
+          ENDIF
+          IF( iom_use( "EPCAL100" ) )  THEN
+              zw2d(:,:) = sinkcal(:,:,ik100) * zfact * tmask(:,:,1) ! Export of calcite at 100m
+              CALL iom_put( "EPCAL100"  , zw2d )
+          ENDIF
+          IF( iom_use( "EPSI100" ) )  THEN
+              zw2d(:,:) =  sinksil(:,:,ik100) * zfact * tmask(:,:,1) ! Export of bigenic silica at 100m
+              CALL iom_put( "EPSI100"  , zw2d )
+          ENDIF
+          IF( iom_use( "EXPC" ) )  THEN
+              zw3d(:,:,:) = ( sinking(:,:,:) + sinking2(:,:,:) ) * zfact * tmask(:,:,:) ! Export of carbon in the water column
+              CALL iom_put( "EXPC"  , zw3d )
+          ENDIF
+          IF( iom_use( "EXPFE" ) )  THEN
+              zw3d(:,:,:) = ( sinkfer(:,:,:) + sinkfer2(:,:,:) ) * zfact * tmask(:,:,:) ! Export of iron 
+              CALL iom_put( "EXPFE"  , zw3d )
+          ENDIF
+          IF( iom_use( "EXPCAL" ) )  THEN
+              zw3d(:,:,:) = sinkcal(:,:,:) * zfact * tmask(:,:,:) ! Export of calcite 
+              CALL iom_put( "EXPCAL"  , zw3d )
+          ENDIF
+          IF( iom_use( "EXPSI" ) )  THEN
+              zw3d(:,:,:) = sinksil(:,:,:) * zfact * tmask(:,:,:) ! Export of bigenic silica
+              CALL iom_put( "EXPSI"  , zw3d )
+          ENDIF
+          IF( iom_use( "tcexp" ) )  CALL iom_put( "tcexp" , t_oce_co2_exp * zfact )   ! molC/s
+          ! 
+          CALL wrk_dealloc( jpi, jpj,      zw2d )
+          CALL wrk_dealloc( jpi, jpj, jpk, zw3d )
+        ENDIF
+      ELSE
+         IF( ln_diatrc ) THEN
+            zfact = 1.e3 * rfact2r
+            trc2d(:,:,jp_pcs0_2d + 4) = sinking (:,:,ik100) * zfact * tmask(:,:,1)
+            trc2d(:,:,jp_pcs0_2d + 5) = sinking2(:,:,ik100) * zfact * tmask(:,:,1)
+            trc2d(:,:,jp_pcs0_2d + 6) = sinkfer (:,:,ik100) * zfact * tmask(:,:,1)
+            trc2d(:,:,jp_pcs0_2d + 7) = sinkfer2(:,:,ik100) * zfact * tmask(:,:,1)
+            trc2d(:,:,jp_pcs0_2d + 8) = sinksil (:,:,ik100) * zfact * tmask(:,:,1)
+            trc2d(:,:,jp_pcs0_2d + 9) = sinkcal (:,:,ik100) * zfact * tmask(:,:,1)
          ENDIF
       ENDIF
@@ -272,5 +309,14 @@
       !!                  ***  ROUTINE p4z_sink_init  ***
       !!----------------------------------------------------------------------
-
+      INTEGER :: jk
+
+      ik100 = 10        !  last level where depth less than 100 m
+      DO jk = jpkm1, 1, -1
+         IF( gdept_1d(jk) > 100. )  ik100 = jk - 1
+      END DO
+      IF (lwp) WRITE(numout,*)
+      IF (lwp) WRITE(numout,*) ' Level corresponding to 100m depth ',  ik100 + 1
+      IF (lwp) WRITE(numout,*)
+      !
       t_oce_co2_exp = 0._wp
       !
@@ -282,5 +328,5 @@
    !!----------------------------------------------------------------------
 
-   SUBROUTINE p4z_sink ( kt, jnt )
+   SUBROUTINE p4z_sink ( kt, knt )
       !!---------------------------------------------------------------------
       !!                ***  ROUTINE p4z_sink  ***
@@ -292,5 +338,5 @@
       !!---------------------------------------------------------------------
       !
-      INTEGER, INTENT(in) :: kt, jnt
+      INTEGER, INTENT(in) :: kt, knt
       !
       INTEGER  :: ji, jj, jk, jit, niter1, niter2
@@ -300,8 +346,10 @@
       REAL(wp) :: zdiv , zdiv1, zdiv2, zdiv3, zdiv4, zdiv5
       REAL(wp) :: zval1, zval2, zval3, zval4
-      REAL(wp) :: zrfact2
+      REAL(wp) :: zfact
       INTEGER  :: ik1
       CHARACTER (len=25) :: charout
       REAL(wp), POINTER, DIMENSION(:,:,:) :: znum3d 
+      REAL(wp), POINTER, DIMENSION(:,:,:) :: zw3d
+      REAL(wp), POINTER, DIMENSION(:,:  ) :: zw2d
       !!---------------------------------------------------------------------
       !
@@ -325,5 +373,5 @@
             DO ji = 1, jpi
                IF( tmask(ji,jj,jk) /= 0.e0 ) THEN
-                  znum = trn(ji,jj,jk,jppoc) / ( trn(ji,jj,jk,jpnum) + rtrn ) / xkr_massp
+                  znum = trb(ji,jj,jk,jppoc) / ( trb(ji,jj,jk,jpnum) + rtrn ) / xkr_massp
                   ! -------------- To avoid sinking speed over 50 m/day -------
                   znum  = MIN( xnumm(jk), znum )
@@ -387,5 +435,5 @@
                IF( tmask(ji,jj,jk) /= 0.e0 ) THEN
 
-                  znum = trn(ji,jj,jk,jppoc)/(trn(ji,jj,jk,jpnum)+rtrn) / xkr_massp
+                  znum = trb(ji,jj,jk,jppoc)/(trb(ji,jj,jk,jpnum)+rtrn) / xkr_massp
                   !-------------- To avoid sinking speed over 50 m/day -------
                   znum  = min(xnumm(jk),znum)
@@ -405,10 +453,10 @@
                   !    ----------------------------------------------
 
-                  zagg1 =  0.163 * trn(ji,jj,jk,jpnum)**2               &
+                  zagg1 =  0.163 * trb(ji,jj,jk,jpnum)**2               &
                      &            * 2.*( (zfm-1.)*(zfm*xkr_mass_max**3-xkr_mass_min**3)    &
                      &            * (zeps-1)/zdiv1 + 3.*(zfm*xkr_mass_max-xkr_mass_min)    &
                      &            * (zfm*xkr_mass_max**2-xkr_mass_min**2)                  &
                      &            * (zeps-1.)**2/(zdiv2*zdiv3)) 
-                  zagg2 =  2*0.163*trn(ji,jj,jk,jpnum)**2*zfm*                       &
+                  zagg2 =  2*0.163*trb(ji,jj,jk,jpnum)**2*zfm*                       &
                      &                   ((xkr_mass_max**3+3.*(xkr_mass_max**2          &
                      &                    *xkr_mass_min*(zeps-1.)/zdiv2                 &
@@ -418,5 +466,5 @@
                      &                    (zeps-2.)+(zeps-1.)/zdiv3)+(zeps-1.)/zdiv1))    
 
-                  zagg3 =  0.163*trn(ji,jj,jk,jpnum)**2*zfm**2*8. * xkr_mass_max**3  
+                  zagg3 =  0.163*trb(ji,jj,jk,jpnum)**2*zfm**2*8. * xkr_mass_max**3  
                   
                  !    Aggregation of small into large particles
@@ -424,5 +472,5 @@
                  !    ----------------------------------------------
 
-                  zagg4 =  2.*3.141*0.125*trn(ji,jj,jk,jpnum)**2*                       &
+                  zagg4 =  2.*3.141*0.125*trb(ji,jj,jk,jpnum)**2*                       &
                      &                 xkr_wsbio_min*(zeps-1.)**2                         &
                      &                 *(xkr_mass_min**2*((1.-zsm*zfm)/(zdiv3*zdiv4)      &
@@ -431,5 +479,5 @@
                      &                 *xkr_eta)/(zdiv*zdiv3*zdiv5) )   
 
-                  zagg5 =   2.*3.141*0.125*trn(ji,jj,jk,jpnum)**2                         &
+                  zagg5 =   2.*3.141*0.125*trb(ji,jj,jk,jpnum)**2                         &
                      &                 *(zeps-1.)*zfm*xkr_wsbio_min                        &
                      &                 *(zsm*(xkr_mass_min**2-zfm*xkr_mass_max**2)         &
@@ -441,5 +489,5 @@
                   !     ------------------------------------
 
-                  zfract = 2.*3.141*0.125*trn(ji,jj,jk,jpmes)*12./0.12/0.06**3*trn(ji,jj,jk,jpnum)  &
+                  zfract = 2.*3.141*0.125*trb(ji,jj,jk,jpmes)*12./0.12/0.06**3*trb(ji,jj,jk,jpnum)  &
                     &      * (0.01/xkr_mass_min)**(1.-zeps)*0.1**2  &
                     &      * 10000.*xstep
@@ -448,8 +496,8 @@
                   !     --------------------------------------
 
-                  zaggdoc = 0.83 * trn(ji,jj,jk,jpdoc) * xstep * xdiss(ji,jj,jk) * trn(ji,jj,jk,jpdoc)   &
-                     &        + 0.005 * 231. * trn(ji,jj,jk,jpdoc) * xstep * trn(ji,jj,jk,jpdoc)
-                  zaggdoc1 = 271. * trn(ji,jj,jk,jppoc) * xstep * xdiss(ji,jj,jk) * trn(ji,jj,jk,jpdoc)  &
-                     &  + 0.02 * 16706. * trn(ji,jj,jk,jppoc) * xstep * trn(ji,jj,jk,jpdoc)
+                  zaggdoc = 0.83 * trb(ji,jj,jk,jpdoc) * xstep * xdiss(ji,jj,jk) * trb(ji,jj,jk,jpdoc)   &
+                     &        + 0.005 * 231. * trb(ji,jj,jk,jpdoc) * xstep * trb(ji,jj,jk,jpdoc)
+                  zaggdoc1 = 271. * trb(ji,jj,jk,jppoc) * xstep * xdiss(ji,jj,jk) * trb(ji,jj,jk,jpdoc)  &
+                     &  + 0.02 * 16706. * trb(ji,jj,jk,jppoc) * xstep * trb(ji,jj,jk,jpdoc)
 
 # if defined key_degrad
@@ -466,5 +514,5 @@
                   zagg = 0.5 * xkr_stick * ( zaggsh + zaggsi )
                   !
-                  znumdoc = trn(ji,jj,jk,jpnum) / ( trn(ji,jj,jk,jppoc) + rtrn )
+                  znumdoc = trb(ji,jj,jk,jpnum) / ( trb(ji,jj,jk,jppoc) + rtrn )
                   tra(ji,jj,jk,jppoc) = tra(ji,jj,jk,jppoc) + zaggdoc + zaggdoc1
                   tra(ji,jj,jk,jpnum) = tra(ji,jj,jk,jpnum) + zfract + zaggdoc / xkr_massp - zagg
@@ -477,35 +525,77 @@
 
      ! Total primary production per year
-     t_oce_co2_exp = t_oce_co2_exp + glob_sum( ( sinking(:,:,:) ) * cvol(:,:,:) )
+     t_oce_co2_exp = t_oce_co2_exp + glob_sum( ( sinking(:,:,ik100) * e1e2t(:,:) * tmask(:,:,1) )
      !
-      IF( ln_diatrc ) THEN
-         !
-         ik1 = iksed + 1
-         zrfact2 = 1.e3 * rfact2r
-         IF( jnt == nrdttrc ) THEN
-           CALL iom_put( "POCFlx"  , sinking (:,:,:)      * zrfact2 * tmask(:,:,:) )  ! POC export
-           CALL iom_put( "NumFlx"  , sinking2 (:,:,:)     * zrfact2 * tmask(:,:,:) )  ! Num export
-           CALL iom_put( "SiFlx"   , sinksil (:,:,:)      * zrfact2 * tmask(:,:,:) )  ! Silica export
-           CALL iom_put( "CaCO3Flx", sinkcal (:,:,:)      * zrfact2 * tmask(:,:,:) )  ! Calcite export
-           CALL iom_put( "xnum"    , znum3d  (:,:,:)                * tmask(:,:,:) )  ! Number of particles in aggregats
-           CALL iom_put( "W1"      , wsbio3  (:,:,:)                * tmask(:,:,:) )  ! sinking speed of POC
-           CALL iom_put( "W2"      , wsbio4  (:,:,:)                * tmask(:,:,:) )  ! sinking speed of aggregats
+     IF( lk_iomput ) THEN
+        IF( knt == nrdttrc ) THEN
+          CALL wrk_alloc( jpi, jpj,      zw2d )
+          CALL wrk_alloc( jpi, jpj, jpk, zw3d )
+          zfact = 1.e+3 * rfact2r  !  conversion from mol/l/kt to  mol/m3/s
+          !
+          IF( iom_use( "EPC100" ) )  THEN
+              zw2d(:,:) = sinking(:,:,ik100) * zfact * tmask(:,:,1) ! Export of carbon at 100m
+              CALL iom_put( "EPC100"  , zw2d )
+          ENDIF
+          IF( iom_use( "EPN100" ) )  THEN
+              zw2d(:,:) = sinking2(:,:,ik100) * zfact * tmask(:,:,1) ! Export of number of aggregates ?
+              CALL iom_put( "EPN100"  , zw2d )
+          ENDIF
+          IF( iom_use( "EPCAL100" ) )  THEN
+              zw2d(:,:) = sinkcal(:,:,ik100) * zfact * tmask(:,:,1) ! Export of calcite at 100m
+              CALL iom_put( "EPCAL100"  , zw2d )
+          ENDIF
+          IF( iom_use( "EPSI100" ) )  THEN
+              zw2d(:,:) = sinksil(:,:,ik100) * zfact * tmask(:,:,1) ! Export of bigenic silica at 100m
+              CALL iom_put( "EPSI100"  , zw2d )
+          ENDIF
+          IF( iom_use( "EXPC" ) )  THEN
+              zw3d(:,:,:) = sinking(:,:,:) * zfact * tmask(:,:,:) ! Export of carbon in the water column
+              CALL iom_put( "EXPC"  , zw3d )
+          ENDIF
+          IF( iom_use( "EXPN" ) )  THEN
+              zw3d(:,:,:) = sinking(:,:,:) * zfact * tmask(:,:,:) ! Export of carbon in the water column
+              CALL iom_put( "EXPN"  , zw3d )
+          ENDIF
+          IF( iom_use( "EXPCAL" ) )  THEN
+              zw3d(:,:,:) = sinkcal(:,:,:) * zfact * tmask(:,:,:) ! Export of calcite 
+              CALL iom_put( "EXPCAL"  , zw3d )
+          ENDIF
+          IF( iom_use( "EXPSI" ) )  THEN
+              zw3d(:,:,:) = sinksil(:,:,:) * zfact * tmask(:,:,:) ! Export of bigenic silica
+              CALL iom_put( "EXPSI"  , zw3d )
+          ENDIF
+          IF( iom_use( "XNUM" ) )  THEN
+              zw3d(:,:,:) =  znum3d(:,:,:) * tmask(:,:,:) !  Number of particles on aggregats
+              CALL iom_put( "XNUM"  , zw3d )
+          ENDIF
+          IF( iom_use( "WSC" ) )  THEN
+              zw3d(:,:,:) = wsbio3(:,:,:) * tmask(:,:,:) ! Sinking speed of carbon particles
+              CALL iom_put( "WSC"  , zw3d )
+          ENDIF
+          IF( iom_use( "WSN" ) )  THEN
+              zw3d(:,:,:) = wsbio4(:,:,:) * tmask(:,:,:) ! Sinking speed of particles number
+              CALL iom_put( "WSN"  , zw3d )
+          ENDIF
+          !
+          CALL wrk_dealloc( jpi, jpj,      zw2d )
+          CALL wrk_dealloc( jpi, jpj, jpk, zw3d )
+      ELSE
+         IF( ln_diatrc ) THEN
+            zfact = 1.e3 * rfact2r
+            trc2d(:,:  ,jp_pcs0_2d + 4)  = sinking (:,:,ik100)  * zfact * tmask(:,:,1)
+            trc2d(:,:  ,jp_pcs0_2d + 5)  = sinking2(:,:,ik100)  * zfact * tmask(:,:,1)
+            trc2d(:,:  ,jp_pcs0_2d + 6)  = sinkfer (:,:,ik100)  * zfact * tmask(:,:,1)
+            trc2d(:,:  ,jp_pcs0_2d + 7)  = sinksil (:,:,ik100)  * zfact * tmask(:,:,1)
+            trc2d(:,:  ,jp_pcs0_2d + 8)  = sinkcal (:,:,ik100)  * zfact * tmask(:,:,1)
+            trc3d(:,:,:,jp_pcs0_3d + 11) = sinking (:,:,:)      * zfact * tmask(:,:,:)
+            trc3d(:,:,:,jp_pcs0_3d + 12) = sinking2(:,:,:)      * zfact * tmask(:,:,:)
+            trc3d(:,:,:,jp_pcs0_3d + 13) = sinksil (:,:,:)      * zfact * tmask(:,:,:)
+            trc3d(:,:,:,jp_pcs0_3d + 14) = sinkcal (:,:,:)      * zfact * tmask(:,:,:)
+            trc3d(:,:,:,jp_pcs0_3d + 15) = znum3d  (:,:,:)              * tmask(:,:,:)
+            trc3d(:,:,:,jp_pcs0_3d + 16) = wsbio3  (:,:,:)              * tmask(:,:,:)
+            trc3d(:,:,:,jp_pcs0_3d + 17) = wsbio4  (:,:,:)              * tmask(:,:,:)
          ENDIF
-# if ! defined key_iomput
-         trc2d(:,:  ,jp_pcs0_2d + 4)  = sinking (:,:,ik1)    * zrfact2 * tmask(:,:,1)
-         trc2d(:,:  ,jp_pcs0_2d + 5)  = sinking2(:,:,ik1)    * zrfact2 * tmask(:,:,1)
-         trc2d(:,:  ,jp_pcs0_2d + 6)  = sinkfer (:,:,ik1)    * zrfact2 * tmask(:,:,1)
-         trc2d(:,:  ,jp_pcs0_2d + 7)  = sinksil (:,:,ik1)    * zrfact2 * tmask(:,:,1)
-         trc2d(:,:  ,jp_pcs0_2d + 8)  = sinkcal (:,:,ik1)    * zrfact2 * tmask(:,:,1)
-         trc3d(:,:,:,jp_pcs0_3d + 11) = sinking (:,:,:)      * zrfact2 * tmask(:,:,:)
-         trc3d(:,:,:,jp_pcs0_3d + 12) = sinking2(:,:,:)      * zrfact2 * tmask(:,:,:)
-         trc3d(:,:,:,jp_pcs0_3d + 13) = sinksil (:,:,:)      * zrfact2 * tmask(:,:,:)
-         trc3d(:,:,:,jp_pcs0_3d + 14) = sinkcal (:,:,:)      * zrfact2 * tmask(:,:,:)
-         trc3d(:,:,:,jp_pcs0_3d + 15) = znum3d  (:,:,:)                * tmask(:,:,:)
-         trc3d(:,:,:,jp_pcs0_3d + 16) = wsbio3  (:,:,:)                * tmask(:,:,:)
-         trc3d(:,:,:,jp_pcs0_3d + 17) = wsbio4  (:,:,:)                * tmask(:,:,:)
-# endif
-        !
       ENDIF
+
       !
       IF(ln_ctl)   THEN  ! print mean trends (used for debugging)
@@ -663,4 +753,12 @@
       END DO
       !
+      ik100 = 10        !  last level where depth less than 100 m
+      DO jk = jpkm1, 1, -1
+         IF( gdept_1d(jk) > 100. )  iksed = jk - 1
+      END DO
+      IF (lwp) WRITE(numout,*)
+      IF (lwp) WRITE(numout,*) ' Level corresponding to 100m depth ',  ik100 + 1
+      IF (lwp) WRITE(numout,*)
+      !
       t_oce_co2_exp = 0._wp
       !
@@ -702,5 +800,5 @@
       ztraz(:,:,:) = 0.e0
       zakz (:,:,:) = 0.e0
-      ztrb (:,:,:) = trn(:,:,:,jp_tra)
+      ztrb (:,:,:) = trb(:,:,:,jp_tra)
 
       DO jk = 1, jpkm1
@@ -717,5 +815,5 @@
          !  first guess of the slopes interior values
          DO jk = 2, jpkm1
-            ztraz(:,:,jk) = ( trn(:,:,jk-1,jp_tra) - trn(:,:,jk,jp_tra) ) * tmask(:,:,jk)
+            ztraz(:,:,jk) = ( trb(:,:,jk-1,jp_tra) - trb(:,:,jk,jp_tra) ) * tmask(:,:,jk)
          END DO
          ztraz(:,:,1  ) = 0.0
@@ -748,5 +846,5 @@
                   zigma = zwsink2(ji,jj,jk+1) * zstep / fse3w(ji,jj,jk+1)
                   zew   = zwsink2(ji,jj,jk+1)
-                  psinkflx(ji,jj,jk+1) = -zew * ( trn(ji,jj,jk,jp_tra) - 0.5 * ( 1 + zigma ) * zakz(ji,jj,jk) ) * zstep
+                  psinkflx(ji,jj,jk+1) = -zew * ( trb(ji,jj,jk,jp_tra) - 0.5 * ( 1 + zigma ) * zakz(ji,jj,jk) ) * zstep
                END DO
             END DO
@@ -761,5 +859,5 @@
                DO ji = 1, jpi
                   zflx = ( psinkflx(ji,jj,jk) - psinkflx(ji,jj,jk+1) ) / fse3t(ji,jj,jk)
-                  trn(ji,jj,jk,jp_tra) = trn(ji,jj,jk,jp_tra) + zflx
+                  trb(ji,jj,jk,jp_tra) = trb(ji,jj,jk,jp_tra) + zflx
                END DO
             END DO
@@ -777,5 +875,5 @@
       END DO
 
-      trn(:,:,:,jp_tra) = ztrb(:,:,:)
+      trb(:,:,:,jp_tra) = ztrb(:,:,:)
       psinkflx(:,:,:)   = 2. * psinkflx(:,:,:)
       !
