Changeset 8169

Timestamp:

2017-06-14T10:04:06+02:00 (7 years ago)

Author:

vancop

Message:

SIMIP outputs: clean ice age, prepare ocean heat flux modification

Location:

branches/2016/v3_6_CMIP6_ice_diagnostics/NEMOGCM/NEMO/LIM_SRC_3

Files:

• limthd.F90 (modified) (2 diffs)
• limupdate1.F90 (modified) (1 diff)
• limupdate2.F90 (modified) (3 diffs)

branches/2016/v3_6_CMIP6_ice_diagnostics/NEMOGCM/NEMO/LIM_SRC_3/limthd.F90

@@ -85 +85 @@
       INTEGER  :: nbpb             ! nb of icy pts for vertical thermo calculations
       INTEGER  :: ii, ij           ! temporary dummy loop index
-      REAL(wp) :: zfric_u, zqld, zqfr
+      REAL(wp) :: zfric_u, zqld, zqfr, zqfr_neg
       REAL(wp) :: zvi_b, zsmv_b, zei_b, zfs_b, zfw_b, zft_b 
       REAL(wp), PARAMETER :: zfric_umin = 0._wp           ! lower bound for the friction velocity (cice value=5.e-04)
@@ -147 +147 @@
 
             ! --- Energy needed to bring ocean surface layer until its freezing (<0, J.m-2) --- !
+            ! includes supercooling potential energy (>0) or "above-freezing" energy (<0)
             zqfr = tmask(ji,jj,1) * rau0 * rcp * fse3t_m(ji,jj) * ( t_bo(ji,jj) - ( sst_m(ji,jj) + rt0 ) )
 
-            ! --- Energy from the turbulent oceanic heat flux (W/m2) --- !
+            ! --- Above-freezing sensible heat content (J/m2 grid)
+            !-> target zqfr_neg = tmask(ji,jj,1) * rau0 * rcp * fse3t_m(ji,jj) * MIN( ( t_bo(ji,jj) - ( sst_m(ji,jj) + rt0 ) ), 0._wp )
+
+            ! --- Sensible ocean-to-ice heat flux (W/m2)
             zfric_u      = MAX( SQRT( ust2s(ji,jj) ), zfric_umin ) 
             fhtur(ji,jj) = MAX( 0._wp, rswitch * rau0 * rcp * zch  * zfric_u * ( ( sst_m(ji,jj) + rt0 ) - t_bo(ji,jj) ) ) ! W.m-2
-
-            !-> MV
-            !-> the following line makes hfxtur often crazily negative
-            !-> if sst is warmer than freezing, evt is fine 
-            !-> but if sst is super-cooled, fhtur = 0 and zqfr > 0
-            !-> so fhtur becomes - zqfr * r1_rdtice / MAX( at_i(ji,jj), epsi10 )
-            !-> if at_i is small, fhtur can be big
-            !-> an we will impose the ice to give energy to the ocean to absorb all super cooling!
-            !-> makes very high values for small ice concentrations, and grows ice vertically very rapidly
-            !-> eg 5th category in hudson bay
-            !-> should check after 10 years, but within a year fhtur is too negative
-            !-> that may help to build up towers
-            ! could we test to put this energy in zqld
-            ! zqfr_pos kept in fhtur
-            ! zqfr_neg added to zqld
-            ! zqfr_pos = MAX( tmask(ji,jj,1) * rau0 * rcp * fse3t_m(ji,jj) * ( t_bo(ji,jj) - ( sst_m(ji,jj) + rt0 ) ), 0. )
-            ! zqfr_neg = MIN( tmask(ji,jj,1) * rau0 * rcp * fse3t_m(ji,jj) * ( t_bo(ji,jj) - ( sst_m(ji,jj) + rt0 ) ), 0. )
-            ! fhtur(ji,jj) = rswitch * MIN( fhtur(ji,jj), - zqfr_pos * r1_rdtice / MAX( at_i(ji,jj), epsi10 ) ) 
-            ! how do we deal with qlead ?
-
+            !-> target fhtur(ji,jj) = rswitch * rau0 * rcp * zch  * zfric_u * ( ( sst_m(ji,jj) + rt0 ) - t_bo(ji,jj) ) ! W.m-2
 
             fhtur(ji,jj) = rswitch * MIN( fhtur(ji,jj), - zqfr * r1_rdtice / MAX( at_i(ji,jj), epsi10 ) )
+            !-> target fhtur(ji,jj) = rswitch * MIN( fhtur(ji,jj), - zqfr_neg * r1_rdtice / MAX( at_i(ji,jj), epsi10 ) )
             ! upper bound for fhtur: the heat retrieved from the ocean must be smaller than the heat necessary to reach 
             !                        the freezing point, so that we do not have SST < T_freeze
             !                        This implies: - ( fhtur(ji,jj) * at_i(ji,jj) * rtdice ) - zqfr >= 0
 
-            !-- Energy Budget of the leads (J.m-2). Must be < 0 to form ice
+            !-- Energy Budget of the leads (J.m-2), source of lateral accretion. Must be < 0 to form ice
             qlead(ji,jj) = MIN( 0._wp , zqld - ( fhtur(ji,jj) * at_i(ji,jj) * rdt_ice ) - zqfr )
 

branches/2016/v3_6_CMIP6_ice_diagnostics/NEMOGCM/NEMO/LIM_SRC_3/limupdate1.F90

@@ -82 +82 @@
                IF( at_i(ji,jj) > rn_amax_2d(ji,jj) .AND. a_i(ji,jj,jl) > 0._wp ) THEN
                   a_i (ji,jj,jl) = a_i (ji,jj,jl) * ( 1._wp - ( 1._wp - rn_amax_2d(ji,jj) / at_i(ji,jj) ) )
-                  oa_i(ji,jj,jl) = oa_i(ji,jj,jl) * ( 1._wp - ( 1._wp - rn_amax_2d(ji,jj) / at_i(ji,jj) ) )
                ENDIF
             END DO

branches/2016/v3_6_CMIP6_ice_diagnostics/NEMOGCM/NEMO/LIM_SRC_3/limupdate2.F90

@@ -78 +78 @@
             IF( v_i(ji,jj,1) > 0._wp .AND. ht_i(ji,jj,1) < rn_himin ) THEN
                a_i (ji,jj,1) = a_i (ji,jj,1) * ht_i(ji,jj,1) / rn_himin
-               oa_i(ji,jj,1) = oa_i(ji,jj,1) * ht_i(ji,jj,1) / rn_himin
             ENDIF
          END DO
@@ -96 +95 @@
                IF( at_i(ji,jj) > rn_amax_2d(ji,jj) .AND. a_i(ji,jj,jl) > 0._wp ) THEN
                   a_i (ji,jj,jl) = a_i (ji,jj,jl) * ( 1._wp - ( 1._wp - rn_amax_2d(ji,jj) / at_i(ji,jj) ) )
-                  oa_i(ji,jj,jl) = oa_i(ji,jj,jl) * ( 1._wp - ( 1._wp - rn_amax_2d(ji,jj) / at_i(ji,jj) ) )
                ENDIF
             END DO
@@ -180 +178 @@
       ! necessary calls (at least for coupling)
       CALL lim_var_glo2eqv
-
-      ! MV SIMIP 2016 small patch to clean ice age outputs
-      WHERE( ( a_i < 5.0e-3 ) .AND. ( ht_i < 1.5 * rn_himin ) ); oa_i(:,:,:) = a_i(:,:,:); END WHERE
 
       CALL lim_var_agg(2)