Changeset 15496

Timestamp:

2021-11-11T13:02:37+01:00 (3 years ago)

Author:

clem

Message:

trunk: solve ticket #2737. The ssh is now adjusted to the init of sea ice, hence the total oce+ice mass remains unchanged across simulations. This applies to both levitating and embedded sea ice. Therefore, results from the configurations with sea ice are changed

File:

• NEMO/trunk/src/ICE/iceistate.F90 (modified) (3 diffs)

NEMO/trunk/src/ICE/iceistate.F90

@@ -75 +75 @@
    INTEGER , PARAMETER ::   jp_hld = 10          ! index of pnd lid depth    (m)
    TYPE(FLD), ALLOCATABLE, DIMENSION(:) ::   si  ! structure of input fields (file informations, fields read)
-
+   !
+#if defined key_agrif
+   REAL(wp), PUBLIC ::   rsshadj   !: initial mean ssh adjustment due to initial ice+snow mass
+#endif
+   !
    !! * Substitutions
 #  include "do_loop_substitute.h90"
@@ -108 +112 @@
       !
       INTEGER  ::   ji, jj, jk, jl         ! dummy loop indices
-      REAL(wp) ::   ztmelts
+      REAL(wp) ::   ztmelts, zsshadj, area
       INTEGER , DIMENSION(4)           ::   itest
       REAL(wp), DIMENSION(jpi,jpj)     ::   z2d
@@ -414 +418 @@
       ENDIF ! ln_iceini
       !
-      !----------------------------------------------
-      ! 4) Snow-ice mass (case ice is fully embedded)
-      !----------------------------------------------
+      !----------------------------------------------------------
+      ! 4) Adjust ssh and vertical scale factors to snow-ice mass
+      !----------------------------------------------------------
       snwice_mass  (:,:) = tmask(:,:,1) * SUM( rhos * v_s + rhoi * v_i + rhow * ( v_ip + v_il ), dim=3  )   ! snow+ice mass
       snwice_mass_b(:,:) = snwice_mass(:,:)
       !
       IF( ln_ice_embd ) THEN            ! embedded sea-ice: deplete the initial ssh below sea-ice area
-         !
+         !                              ! ----------------
          ssh(:,:,Kmm) = ssh(:,:,Kmm) - snwice_mass(:,:) * r1_rho0
          ssh(:,:,Kbb) = ssh(:,:,Kbb) - snwice_mass(:,:) * r1_rho0
          !
+      ELSE                              ! levitating sea-ice: deplete the initial ssh over the whole domain
+         !                              ! ------------------
+         area    = glob_sum( 'iceistate', e1e2t(:,:) * ssmask(:,:) )
+         zsshadj = glob_sum( 'iceistate', snwice_mass(:,:) * r1_rho0 * e1e2t(:,:) ) / area
+#if defined key_agrif
+         ! Override ssh adjustment in nested domains by the root-domain ssh adjustment;
+         ! store the adjustment value in a global module variable to make it retrievable in nested domains
+         IF( .NOT.Agrif_Root() ) THEN
+            zsshadj = Agrif_Parent(rsshadj)
+         ELSE
+            rsshadj = zsshadj
+         ENDIF
+#endif
+         IF(lwp) WRITE(numout,'(A23,F10.6,A20)') ' sea level adjusted by ', -zsshadj, ' m to compensate for'
+         IF(lwp) WRITE(numout,*) ' the initial snow+ice mass'
+         !
+         WHERE( ssmask(:,:) == 1._wp )
+            ssh(:,:,Kmm) = ssh(:,:,Kmm) - zsshadj
+            ssh(:,:,Kbb) = ssh(:,:,Kbb) - zsshadj
+         ENDWHERE
+         !
+      ENDIF
+      !
+      IF( .NOT.ln_linssh ) THEN
 #if defined key_qco
-         IF( .NOT.ln_linssh )   CALL dom_qco_zgr( Kbb, Kmm )        ! upadte of r3=ssh/h0 ratios
+         CALL dom_qco_zgr( Kbb, Kmm )        ! upadte of r3=ssh/h0 ratios
 #elif defined key_linssh
-         !                                                          ! fix in time coord. : no update of vertical coord.
+         !                                   ! Fix in time : key_linssh case, set through domzgr_substitute.h90
 #else
-         IF( .NOT.ln_linssh )   CALL dom_vvl_zgr( Kbb, Kmm, Kaa )   ! interpolation scale factor, depth and water column
+         DO jk = 1, jpk
+            DO_2D( nn_hls, nn_hls, nn_hls, nn_hls)
+               IF( snwice_mass(ji,jj) /= 0._wp ) THEN
+                  e3t(ji,jj,jk,Kmm) = e3t_0(ji,jj,jk) * ( 1._wp + ssh(ji,jj,Kmm) * r1_ht_0(ji,jj) * tmask(ji,jj,jk) )
+                  e3t(ji,jj,jk,Kbb) = e3t_0(ji,jj,jk) * ( 1._wp + ssh(ji,jj,Kbb) * r1_ht_0(ji,jj) * tmask(ji,jj,jk) )
+               ENDIF
+            END_2D
+         END DO
+         !
+         CALL dom_vvl_zgr( Kbb, Kmm, Kaa )   ! interpolation of scale factor, depth and water column
 #endif
-
       ENDIF
-
+      !
       !!clem: output of initial state should be written here but it is impossible because
       !!      the ocean and ice are in the same file