Index: branches/UKMO/dev_r5518_GO6_package/NEMOGCM/NEMO/OPA_SRC/TRA/tranxt.F90
===================================================================
--- branches/UKMO/dev_r5518_GO6_package/NEMOGCM/NEMO/OPA_SRC/TRA/tranxt.F90	(revision 6486)
+++ branches/UKMO/dev_r5518_GO6_package/NEMOGCM/NEMO/OPA_SRC/TRA/tranxt.F90	(revision 6487)
@@ -28,4 +28,5 @@
    USE sbc_oce         ! surface boundary condition: ocean
    USE sbcrnf          ! river runoffs
+   USE sbcisf          ! ice shelf melting/freezing
    USE zdf_oce         ! ocean vertical mixing
    USE domvvl          ! variable volume
@@ -46,5 +47,4 @@
    USE timing          ! Timing
 #if defined key_agrif
-   USE agrif_opa_update
    USE agrif_opa_interp
 #endif
@@ -110,4 +110,8 @@
       ! Update after tracer on domain lateral boundaries
       ! 
+#if defined key_agrif
+      CALL Agrif_tra                     ! AGRIF zoom boundaries
+#endif
+      !
       CALL lbc_lnk( tsa(:,:,:,jp_tem), 'T', 1._wp )      ! local domain boundaries  (T-point, unchanged sign)
       CALL lbc_lnk( tsa(:,:,:,jp_sal), 'T', 1._wp )
@@ -115,7 +119,4 @@
 #if defined key_bdy 
       IF( lk_bdy )   CALL bdy_tra( kt )  ! BDY open boundaries
-#endif
-#if defined key_agrif
-      CALL Agrif_tra                     ! AGRIF zoom boundaries
 #endif
  
@@ -148,12 +149,7 @@
          ELSE                 ;   CALL tra_nxt_fix( kt, nit000,         'TRA', tsb, tsn, tsa, jpts )  ! fixed    volume level 
          ENDIF
-      ENDIF 
-      !
-#if defined key_agrif
-      ! Update tracer at AGRIF zoom boundaries
-      IF( .NOT.Agrif_Root() )    CALL Agrif_Update_Tra( kt )      ! children only
-#endif      
-      !
-      ! trends computation
+      ENDIF     
+      !
+     ! trends computation
       IF( l_trdtra ) THEN      ! trend of the Asselin filter (tb filtered - tb)/dt     
          DO jk = 1, jpkm1
@@ -279,5 +275,5 @@
 
       !!     
-      LOGICAL  ::   ll_tra_hpg, ll_traqsr, ll_rnf   ! local logical
+      LOGICAL  ::   ll_tra_hpg, ll_traqsr, ll_rnf, ll_isf   ! local logical
       INTEGER  ::   ji, jj, jk, jn              ! dummy loop indices
       REAL(wp) ::   zfact1, ztc_a , ztc_n , ztc_b , ztc_f , ztc_d    ! local scalar
@@ -295,8 +291,14 @@
          ll_traqsr  = ln_traqsr        ! active  tracers case  and  solar penetration
          ll_rnf     = ln_rnf           ! active  tracers case  and  river runoffs
+         IF (nn_isf .GE. 1) THEN 
+            ll_isf = .TRUE.            ! active  tracers case  and  ice shelf melting/freezing
+         ELSE
+            ll_isf = .FALSE.
+         END IF
       ELSE                          
          ll_tra_hpg = .FALSE.          ! passive tracers case or NO semi-implicit hpg
          ll_traqsr  = .FALSE.          ! active  tracers case and NO solar penetration
          ll_rnf     = .FALSE.          ! passive tracers or NO river runoffs
+         ll_isf     = .FALSE.          ! passive tracers or NO ice shelf melting/freezing
       ENDIF
       !
@@ -321,15 +323,31 @@
                   ztc_f  = ztc_n  + atfp * ztc_d
                   !
-                  IF( jk == 1 ) THEN           ! first level 
-                     ze3t_f = ze3t_f - zfact2 * ( emp_b(ji,jj) - emp(ji,jj) + rnf(ji,jj) - rnf_b(ji,jj) )
+                  IF( jk == mikt(ji,jj) ) THEN           ! first level 
+                     ze3t_f = ze3t_f - zfact2 * ( (emp_b(ji,jj)    - emp(ji,jj)   )  &
+                            &                   - (rnf_b(ji,jj)    - rnf(ji,jj)   )  &
+                            &                   + (fwfisf_b(ji,jj) - fwfisf(ji,jj))  )
                      ztc_f  = ztc_f  - zfact1 * ( psbc_tc(ji,jj,jn) - psbc_tc_b(ji,jj,jn) )
                   ENDIF
 
-                  IF( ll_traqsr .AND. jn == jp_tem .AND. jk <= nksr )   &     ! solar penetration (temperature only)
+                  ! solar penetration (temperature only)
+                  IF( ll_traqsr .AND. jn == jp_tem .AND. jk <= nksr )                            & 
                      &     ztc_f  = ztc_f  - zfact1 * ( qsr_hc(ji,jj,jk) - qsr_hc_b(ji,jj,jk) ) 
 
-                  IF( ll_rnf .AND. jk <= nk_rnf(ji,jj) )   & 		      ! river runoffs
+                  ! river runoff
+                  IF( ll_rnf .AND. jk <= nk_rnf(ji,jj) )                                          &
                      &     ztc_f  = ztc_f  - zfact1 * ( rnf_tsc(ji,jj,jn) - rnf_tsc_b(ji,jj,jn) ) & 
                      &                              * fse3t_n(ji,jj,jk) / h_rnf(ji,jj)
+
+                  ! ice shelf
+                  IF( ll_isf ) THEN
+                     ! level fully include in the Losch_2008 ice shelf boundary layer
+                     IF ( jk >= misfkt(ji,jj) .AND. jk < misfkb(ji,jj) )                          &
+                        ztc_f  = ztc_f  - zfact1 * ( risf_tsc(ji,jj,jn) - risf_tsc_b(ji,jj,jn) )  &
+                               &                 * fse3t_n(ji,jj,jk) * r1_hisf_tbl (ji,jj)
+                     ! level partially include in Losch_2008 ice shelf boundary layer 
+                     IF ( jk == misfkb(ji,jj) )                                                   &
+                        ztc_f  = ztc_f  - zfact1 * ( risf_tsc(ji,jj,jn) - risf_tsc_b(ji,jj,jn) )  &
+                               &                 * fse3t_n(ji,jj,jk) * r1_hisf_tbl (ji,jj) * ralpha(ji,jj)
+                  END IF
 
                   ze3t_f = 1.e0 / ze3t_f
