Changeset 5708 for branches/UKMO/dev_r5518_coupling_GSI7_GSI8_landice/NEMOGCM/NEMO/OPA_SRC/SBC/sbcisf.F90

Timestamp:

2015-08-26T14:49:08+02:00 (9 years ago)

Author:

davestorkey

Message:

Commit changes for icesheet freshwater input code for coupled models without an active icesheet model.

File:

• branches/UKMO/dev_r5518_coupling_GSI7_GSI8_landice/NEMOGCM/NEMO/OPA_SRC/SBC/sbcisf.F90 (modified) (4 diffs)

branches/UKMO/dev_r5518_coupling_GSI7_GSI8_landice/NEMOGCM/NEMO/OPA_SRC/SBC/sbcisf.F90

@@ -27 +27 @@
    USE fldread         ! read input field at current time step
 
-
-
    IMPLICIT NONE
    PRIVATE
@@ -90 +88 @@
     INTEGER                      ::   ji, jj, jk, ijkmin, inum, ierror
     INTEGER                      ::   ikt, ikb   ! top and bottom level of the isf boundary layer
+    REAL(wp)                     ::   zgreenland_fwfisf_sum, zantarctica_fwfisf_sum
     REAL(wp)                     ::   rmin
     REAL(wp)                     ::   zhk
@@ -256 +255 @@
             CALL fld_read ( kt, nn_fsbc, sf_rnfisf   )
             fwfisf(:,:) = - sf_rnfisf(1)%fnow(:,:,1)         ! fresh water flux from the isf (fwfisf <0 mean melting) 
+
+            IF( lk_oasis) THEN
+            ! ln_coupled_iceshelf_fluxes uninitialised unless lk_oasis=true
+            IF( ln_coupled_iceshelf_fluxes ) THEN
+
+              ! Adjust total iceshelf melt rates so that sum of iceberg calving and iceshelf melting in the northern
+              ! and southern hemispheres equals rate of increase of mass of greenland and antarctic ice sheets
+              ! to preserve total freshwater conservation in coupled models without an active ice sheet model.
+
+               zgreenland_fwfisf_sum = SUM( fwfisf(:,:) * e1t(:,:) * e2t(:,:) * greenland_icesheet_mask(:,:) )
+               IF( lk_mpp ) CALL mpp_sum( zgreenland_fwfisf_sum )
+               ! use ABS function because we need to preserve the sign of fwfisf
+               WHERE( greenland_icesheet_mask(:,:) == 1.0 )                                                                  &
+              &    fwfisf(:,:) = fwfisf(:,:)  * ABS( greenland_icesheet_mass_rate_of_change * (1.0-rn_greenland_calving_fraction) &
+              &                           / ( zgreenland_fwfisf_sum + 1.0e-10_wp ) )
+
+               ! check
+               WRITE(numout, *) 'Greenland iceshelf melting climatology (kg/s) : ',zgreenland_fwfisf_sum
+               zgreenland_fwfisf_sum = SUM( fwfisf(:,:) * e1t(:,:) * e2t(:,:) * greenland_icesheet_mask(:,:) )
+               IF( lk_mpp ) CALL mpp_sum( zgreenland_fwfisf_sum )
+               WRITE(numout, *) 'Greenland iceshelf melting adjusted value (kg/s) : ',zgreenland_fwfisf_sum
+
+               zantarctica_fwfisf_sum = SUM( fwfisf(:,:) * e1t(:,:) * e2t(:,:) * antarctica_icesheet_mask(:,:) )
+               IF( lk_mpp ) CALL mpp_sum( zantarctica_fwfisf_sum )
+               ! use ABS function because we need to preserve the sign of fwfisf
+               WHERE( antarctica_icesheet_mask(:,:) == 1.0 ) &
+              &    fwfisf(:,:) = fwfisf(:,:)  * ABS( antarctica_icesheet_mass_rate_of_change * (1.0-rn_antarctica_calving_fraction) &
+              &                           / ( zantarctica_fwfisf_sum + 1.0e-10_wp ) )
+      
+               ! check
+               WRITE(numout, *) 'Antarctica iceshelf melting climatology (kg/s) : ',zantarctica_fwfisf_sum
+               zantarctica_fwfisf_sum = SUM( fwfisf(:,:) * e1t(:,:) * e2t(:,:) * antarctica_icesheet_mask(:,:) )
+               IF( lk_mpp ) CALL mpp_sum( zantarctica_fwfisf_sum )
+               WRITE(numout, *) 'Antarctica iceshelf melting adjusted value (kg/s) : ',zantarctica_fwfisf_sum
+
+            ENDIF
+            ENDIF
+
             qisf(:,:)   = fwfisf(:,:) * lfusisf              ! heat        flux
             stbl(:,:)   = soce
@@ -264 +301 @@
             !CALL fld_read ( kt, nn_fsbc, sf_qisf   )
             fwfisf(:,:) = sf_fwfisf(1)%fnow(:,:,1)            ! fwf
+
+            IF( lk_oasis) THEN
+            ! ln_coupled_iceshelf_fluxes uninitialised unless lk_oasis=true
+            IF( ln_coupled_iceshelf_fluxes ) THEN
+
+              ! Adjust total iceshelf melt rates so that sum of iceberg calving and iceshelf melting in the northern
+              ! and southern hemispheres equals rate of increase of mass of greenland and antarctic ice sheets
+              ! to preserve total freshwater conservation in coupled models without an active ice sheet model.
+
+               zgreenland_fwfisf_sum = SUM( fwfisf(:,:) * e1t(:,:) * e2t(:,:) * greenland_icesheet_mask(:,:) )
+               IF( lk_mpp ) CALL mpp_sum( zgreenland_fwfisf_sum )
+               ! use ABS function because we need to preserve the sign of fwfisf
+               WHERE( greenland_icesheet_mask(:,:) == 1.0 )                                                                  &
+              &    fwfisf(:,:) = fwfisf(:,:)  * ABS( greenland_icesheet_mass_rate_of_change * (1.0-rn_greenland_calving_fraction) &
+              &                           / ( zgreenland_fwfisf_sum + 1.0e-10_wp ) )
+
+               ! check
+               WRITE(numout, *) 'Greenland iceshelf melting climatology (kg/s) : ',zgreenland_fwfisf_sum
+               zgreenland_fwfisf_sum = SUM( fwfisf(:,:) * e1t(:,:) * e2t(:,:) * greenland_icesheet_mask(:,:) )
+               IF( lk_mpp ) CALL mpp_sum( zgreenland_fwfisf_sum )
+               WRITE(numout, *) 'Greenland iceshelf melting adjusted value (kg/s) : ',zgreenland_fwfisf_sum
+
+               zantarctica_fwfisf_sum = SUM( fwfisf(:,:) * e1t(:,:) * e2t(:,:) * antarctica_icesheet_mask(:,:) )
+               IF( lk_mpp ) CALL mpp_sum( zantarctica_fwfisf_sum )
+               ! use ABS function because we need to preserve the sign of fwfisf
+               WHERE( antarctica_icesheet_mask(:,:) == 1.0 ) &
+              &    fwfisf(:,:) = fwfisf(:,:)  * ABS( antarctica_icesheet_mass_rate_of_change * (1.0-rn_antarctica_calving_fraction) &
+              &                           / ( zantarctica_fwfisf_sum + 1.0e-10_wp ) )
+      
+               ! check
+               WRITE(numout, *) 'Antarctica iceshelf melting climatology (kg/s) : ',zantarctica_fwfisf_sum
+               zantarctica_fwfisf_sum = SUM( fwfisf(:,:) * e1t(:,:) * e2t(:,:) * antarctica_icesheet_mask(:,:) )
+               IF( lk_mpp ) CALL mpp_sum( zantarctica_fwfisf_sum )
+               WRITE(numout, *) 'Antarctica iceshelf melting adjusted value (kg/s) : ',zantarctica_fwfisf_sum
+
+            ENDIF
+            ENDIF
+
             qisf(:,:)   = fwfisf(:,:) * lfusisf              ! heat        flux
             !qisf(:,:)   = sf_qisf(1)%fnow(:,:,1)              ! heat flux