Changeset 11480 for NEMO/branches/2019/dev_r10721_KERNEL-02_Storkey_Coward_IMMERSE_first_steps/src/OCE/DYN/sshwzv.F90

Timestamp:

2019-08-29T11:23:25+02:00 (5 years ago)

Author:

davestorkey

Message:

2019/dev_r10721_KERNEL-02_Storkey_Coward_IMMERSE_first_steps : Merge in changes from branch of branch.
Main changes:

1. "nxt" modules renamed as "atf" and now just do Asselin time filtering. The time level swapping is achieved by swapping indices.
2. Some additional prognostic grid variables changed to use a time dimension.

Notes:

1. This merged branch passes SETTE tests but does not identical results to the SETTE tests with the trunk@10721 unless minor bugs to do with Euler timestepping and the OFF timestepping are fixed in the trunk (NEMO tickets #2310 and #2311).
2. The nn_dttrc > 1 option for TOP (TOP has a different timestep to OCE) doesn't work. But it doesn't work in the trunk or NEMO 4.0 release either.

File:

• NEMO/branches/2019/dev_r10721_KERNEL-02_Storkey_Coward_IMMERSE_first_steps/src/OCE/DYN/sshwzv.F90 (modified) (3 diffs)

NEMO/branches/2019/dev_r10721_KERNEL-02_Storkey_Coward_IMMERSE_first_steps/src/OCE/DYN/sshwzv.F90

@@ -9 +9 @@
    !!             -   !  2010-09  (D.Storkey and E.O'Dea) bug fixes for BDY module
    !!            3.3  !  2011-10  (M. Leclair) split former ssh_wzv routine and remove all vvl related work
+   !!            4.1  !  2019-08  (A. Coward, D. Storkey) Rename ssh_nxt -> ssh_atf. Now only does time filtering.
    !!----------------------------------------------------------------------
 
    !!----------------------------------------------------------------------
    !!   ssh_nxt       : after ssh
-   !!   ssh_swp       : filter ans swap the ssh arrays
+   !!   ssh_atf       : time filter the ssh arrays
    !!   wzv           : compute now vertical velocity
    !!----------------------------------------------------------------------
@@ -43 +44 @@
    PUBLIC   wzv        ! called by step.F90
    PUBLIC   wAimp      ! called by step.F90
-   PUBLIC   ssh_swp    ! called by step.F90
+   PUBLIC   ssh_atf    ! called by step.F90
 
    !! * Substitutions
@@ -218 +219 @@
 
 
-   SUBROUTINE ssh_swp( kt, Kbb, Kmm, Kaa )
-      !!----------------------------------------------------------------------
-      !!                    ***  ROUTINE ssh_nxt  ***
-      !!
-      !! ** Purpose :   achieve the sea surface  height time stepping by 
-      !!              applying Asselin time filter and swapping the arrays
-      !!              ssh(:,:,Kaa)  already computed in ssh_nxt  
+   SUBROUTINE ssh_atf( kt, Kbb, Kmm, Kaa, pssh )
+      !!----------------------------------------------------------------------
+      !!                    ***  ROUTINE ssh_atf  ***
+      !!
+      !! ** Purpose :   Apply Asselin time filter to now SSH.
       !!
       !! ** Method  : - apply Asselin time fiter to now ssh (excluding the forcing
       !!              from the filter, see Leclair and Madec 2010) and swap :
-      !!                ssh(:,:,Kmm) = ssh(:,:,Kaa) + atfp * ( ssh(:,:,Kbb) -2 ssh(:,:,Kmm) + ssh(:,:,Kaa) )
+      !!                pssh(:,:,Kmm) = pssh(:,:,Kaa) + atfp * ( pssh(:,:,Kbb) -2 pssh(:,:,Kmm) + pssh(:,:,Kaa) )
       !!                            - atfp * rdt * ( emp_b - emp ) / rau0
-      !!                ssh(:,:,Kmm) = ssh(:,:,Kaa)
-      !!
-      !! ** action  : - ssh(:,:,Kbb), ssh(:,:,Kmm)   : before & now sea surface height
-      !!                               ready for the next time step
+      !!
+      !! ** action  : - pssh(:,:,Kmm) time filtered
       !!
       !! Reference  : Leclair, M., and G. Madec, 2009, Ocean Modelling.
       !!----------------------------------------------------------------------
-      INTEGER, INTENT(in) ::   kt              ! ocean time-step index
-      INTEGER, INTENT(in) ::   Kbb, Kmm, Kaa   ! ocean time-step index
+      INTEGER                         , INTENT(in   ) ::   kt             ! ocean time-step index
+      INTEGER                         , INTENT(in   ) ::   Kbb, Kmm, Kaa  ! ocean time level indices
+      REAL(wp), DIMENSION(jpi,jpj,jpt), INTENT(inout) ::   pssh           ! SSH field
       !
       REAL(wp) ::   zcoef   ! local scalar
       !!----------------------------------------------------------------------
       !
-      IF( ln_timing )   CALL timing_start('ssh_swp')
+      IF( ln_timing )   CALL timing_start('ssh_atf')
       !
       IF( kt == nit000 ) THEN
          IF(lwp) WRITE(numout,*)
-         IF(lwp) WRITE(numout,*) 'ssh_swp : Asselin time filter and swap of sea surface height'
+         IF(lwp) WRITE(numout,*) 'ssh_atf : Asselin time filter of sea surface height'
          IF(lwp) WRITE(numout,*) '~~~~~~~ '
       ENDIF
       !              !==  Euler time-stepping: no filter, just swap  ==!
-      IF ( neuler == 0 .AND. kt == nit000 ) THEN
-         ssh(:,:,Kmm) = ssh(:,:,Kaa)                              ! now    <-- after  (before already = now)
-         !
-      ELSE           !==  Leap-Frog time-stepping: Asselin filter + swap  ==!
-         !                                                  ! before <-- now filtered
-         ssh(:,:,Kbb) = ssh(:,:,Kmm) + atfp * ( ssh(:,:,Kbb) - 2 * ssh(:,:,Kmm) + ssh(:,:,Kaa) )
-         IF( .NOT.ln_linssh ) THEN                          ! before <-- with forcing removed
+      IF ( .NOT.( neuler == 0 .AND. kt == nit000 ) ) THEN   ! Only do time filtering for leapfrog timesteps
+         !                                                  ! filtered "now" field
+         pssh(:,:,Kmm) = pssh(:,:,Kmm) + atfp * ( pssh(:,:,Kbb) - 2 * pssh(:,:,Kmm) + pssh(:,:,Kaa) )
+         IF( .NOT.ln_linssh ) THEN                          ! "now" <-- with forcing removed
             zcoef = atfp * rdt * r1_rau0
-            ssh(:,:,Kbb) = ssh(:,:,Kbb) - zcoef * (     emp_b(:,:) - emp   (:,:)   &
+            pssh(:,:,Kmm) = pssh(:,:,Kmm) - zcoef * (     emp_b(:,:) - emp   (:,:)   &
                &                             -    rnf_b(:,:) + rnf   (:,:)   &
                &                             + fwfisf_b(:,:) - fwfisf(:,:)   ) * ssmask(:,:)
          ENDIF
-         ssh(:,:,Kmm) = ssh(:,:,Kaa)                              ! now <-- after
-      ENDIF
-      !
-      IF(ln_ctl)   CALL prt_ctl( tab2d_1=ssh(:,:,Kbb), clinfo1=' ssh(:,:,Kbb)  - : ', mask1=tmask )
-      !
-      IF( ln_timing )   CALL timing_stop('ssh_swp')
-      !
-   END SUBROUTINE ssh_swp
+      ENDIF
+      !
+      IF(ln_ctl)   CALL prt_ctl( tab2d_1=pssh(:,:,Kmm), clinfo1=' pssh(:,:,Kmm)  - : ', mask1=tmask )
+      !
+      IF( ln_timing )   CALL timing_stop('ssh_atf')
+      !
+   END SUBROUTINE ssh_atf
 
    SUBROUTINE wAimp( kt, Kmm )