Changeset 12397 for NEMO/branches/2020/KERNEL-03_Storkey_Coward_RK3_stage2/src/OCE/DYN/dynspg_ts.F90

Timestamp:

2020-02-18T11:58:37+01:00 (4 years ago)

Author:

davestorkey

Message:

2020/KERNEL-03_Storkey_Coward_RK3_stage2 : Consolidation of code to
handle initial Euler timestep in the context of leapfrog
timestepping. This version passes all SETTE tests but fails to bit
compare with the control for several tests (ORCA2_ICE_PISCES, AMM12,
ISOMIP, AGRIF_DEMO, SPITZ12).

File:

• NEMO/branches/2020/KERNEL-03_Storkey_Coward_RK3_stage2/src/OCE/DYN/dynspg_ts.F90 (modified) (5 diffs)

NEMO/branches/2020/KERNEL-03_Storkey_Coward_RK3_stage2/src/OCE/DYN/dynspg_ts.F90

@@ -180 +180 @@
 !     zwdramp = 1._wp / (rn_wdmin2 - rn_wdmin1) ! more general ramp
       !                                         ! inverse of baroclinic time step 
-      IF( kt == nit000 .AND. neuler == 0 ) THEN   ;   r1_2dt_b = 1._wp / (         rdt )
-      ELSE                                        ;   r1_2dt_b = 1._wp / ( 2._wp * rdt )
-      ENDIF
+      r1_2dt_b = 1._wp / r2dt 
       !
       ll_init     = ln_bt_av                    ! if no time averaging, then no specific restart 
@@ -198 +196 @@
          IF(lwp) WRITE(numout,*)
          !
-         IF( neuler == 0 )   ll_init=.TRUE.
-         !
-         IF( ln_bt_fw .OR. neuler == 0 ) THEN
+         IF( l_1st_euler )   ll_init=.TRUE.
+         !
+         IF( ln_bt_fw .OR. l_1st_euler ) THEN
             ll_fw_start =.TRUE.
             noffset     = 0
@@ -209 +207 @@
          CALL ts_wgt( ln_bt_av, ll_fw_start, icycle, wgtbtp1, wgtbtp2 )
          !
-      ENDIF
-      !
-      ! If forward start at previous time step, and centered integration, 
-      ! then update averaging weights:
-      IF (.NOT.ln_bt_fw .AND.( neuler==0 .AND. kt==nit000+1 ) ) THEN
-         ll_fw_start=.FALSE.
-         CALL ts_wgt( ln_bt_av, ll_fw_start, icycle, wgtbtp1, wgtbtp2 )
-      ENDIF
-      !
-                          
+      ELSEIF( kt == nit000 + 1 ) THEN           !* initialisation 2nd time-step
+         !
+         IF( .NOT.ln_bt_fw ) THEN
+            ! If we did an Euler timestep on the first timestep we need to reset ll_fw_start
+            ! and the averaging weights. We don't have an easy way of telling whether we did
+            ! an Euler timestep on the first timestep (because l_1st_euler is reset to .false.
+            ! at the end of the first timestep) so just do this in all cases. 
+            ll_fw_start = .FALSE.
+            CALL ts_wgt( ln_bt_av, ll_fw_start, icycle, wgtbtp1, wgtbtp2 )
+         ENDIF
+         !
+      ENDIF
+      !
       ! -----------------------------------------------------------------------------
       !  Phase 1 : Coupling between general trend and barotropic estimates (1st step)
@@ -701 +702 @@
       ! Set advection velocity correction:
       IF (ln_bt_fw) THEN
-         IF( .NOT.( kt == nit000 .AND. neuler==0 ) ) THEN
+         IF( .NOT.( kt == nit000 .AND. l_1st_euler ) ) THEN
             DO_2D_11_11
                zun_save = un_adv(ji,jj)
@@ -889 +890 @@
       IF( TRIM(cdrw) == 'READ' ) THEN        ! Read/initialise 
          !                                   ! ---------------
-         IF( ln_rstart .AND. ln_bt_fw .AND. (neuler/=0) ) THEN    !* Read the restart file
+         IF( ln_rstart .AND. ln_bt_fw .AND. (.NOT.l_1st_euler) ) THEN    !* Read the restart file
             CALL iom_get( numror, jpdom_autoglo, 'ub2_b'  , ub2_b  (:,:), ldxios = lrxios )   
             CALL iom_get( numror, jpdom_autoglo, 'vb2_b'  , vb2_b  (:,:), ldxios = lrxios )