Changeset 15602 for NEMO/branches/UKMO/NEMO_4.0.4_FOAM_pcbias/src/OCE/DYN/dynhpg.F90

Timestamp:

2021-12-16T10:11:36+01:00 (3 years ago)

Author:

jenniewaters

Message:

Code changes to get pcbias working.

File:

• NEMO/branches/UKMO/NEMO_4.0.4_FOAM_pcbias/src/OCE/DYN/dynhpg.F90 (modified) (4 diffs)

NEMO/branches/UKMO/NEMO_4.0.4_FOAM_pcbias/src/OCE/DYN/dynhpg.F90

@@ -46 +46 @@
    USE timing          ! Timing
    USE iom
+   USE biaspar         ! bias correction variables
 
    IMPLICIT NONE
@@ -92 +93 @@
       !!----------------------------------------------------------------------
       INTEGER, INTENT(in) ::   kt   ! ocean time-step index
-      REAL(wp), ALLOCATABLE, DIMENSION(:,:,:) ::   ztrdu, ztrdv
+      INTEGER                                   ::   ji, jj, jk                 ! dummy loop indices
+      INTEGER                                   ::   iku, ikv                   ! k indices for bottom level at u and v points
+      INTEGER                                   ::   numf
+      REAL(wp), POINTER, DIMENSION(:,:,:)       ::   ztrdu, ztrdv
+      REAL(wp), ALLOCATABLE, DIMENSION(:,:,:)   ::   z_rhd_st, z_rhd_diff       ! tmp density storage for pressure corr
+      REAL(wp), ALLOCATABLE, DIMENSION(:,:,:)   ::   z_ua, z_va                 ! tmp store for ua and va including hpg but not pressure correction 
+      REAL(wp), ALLOCATABLE, DIMENSION(:,:,:)   ::   z_ua_bpc, z_va_bpc         ! ua calculated with bias pressure correction  
+      REAL(wp), ALLOCATABLE, DIMENSION(:,:)     ::   z_ua_bpc_bot, z_va_bpc_bot ! bias pc fields calculated at the ocean bottom
       !!----------------------------------------------------------------------
       !
@@ -102 +110 @@
          ztrdv(:,:,:) = va(:,:,:)
       ENDIF
+      !
+      IF ( ln_bias .AND. ln_bias_pc_app ) THEN
+
+         ! allocate space for tempory variables for the bias pressure correction (bpc)
+         ALLOCATE( z_rhd_st(jpi,jpj,jpk), &
+            &      z_ua(jpi,jpj,jpk),     &
+            &      z_va(jpi,jpj,jpk),     &  
+            &      z_ua_bpc(jpi,jpj,jpk), &
+            &      z_va_bpc(jpi,jpj,jpk), & 
+            &      z_ua_bpc_bot(jpi,jpj), &
+            &      z_va_bpc_bot(jpi,jpj), & 
+       &      z_rhd_diff(jpi,jpj,jpk)&
+            &    )
+
+         ! save the original acceleration trends 
+         ! (z_ua_bpc, z_va_bpc are used as temporary storage)
+         z_ua_bpc(:,:,:)     = ua(:,:,:)
+         z_va_bpc(:,:,:)     = va(:,:,:)
+         
+      END IF
       !
       SELECT CASE ( nhpg )      ! Hydrostatic pressure gradient computation
@@ -112 +140 @@
       END SELECT
       !
+      IF ( ln_bias .AND. ln_bias_pc_app ) THEN
+
+         ! The aim here is to calculate the contribution of the bpc to the acceleration terms.
+         ! This is done so that the effect of the bpc on the hpg at the bottom can be removed.
+         ! In order to do that:
+         !    1. The hpg calculation is done again, but with the contributions of the bpc included.
+         !    2. The difference between the acceleration terms (w and w/o bpc) is then calculated.
+         !    3. The effect of the bpc on the bottom hpg is then removed.
+         !    4. The total change to the acceleration terms is then calculated.
+         
+         ! The original density field (without the bpc) is stored.          
+         z_rhd_st(:,:,:) = rhd(:,:,:)
+
+         ! Set the density used in the hpc calculations to the value including the effect of the bpc.
+         rhd(:,:,:)      = rhd_pc(:,:,:) 
+            
+         ! save the acceleration trends including hpg field but calculated without the bpc fields
+         z_ua(:,:,:)     = ua(:,:,:)
+         z_va(:,:,:)     = va(:,:,:)
+
+         ! reset the acceleration trends to their original values
+         ua(:,:,:)       = z_ua_bpc(:,:,:)    
+         va(:,:,:)       = z_va_bpc(:,:,:)  
+
+         ! re-calculate the horizontal pressure gradients with the bpc fields 
+         SELECT CASE ( nhpg )      ! Hydrostatic pressure gradient computation
+         CASE (  np_zco )   ;   CALL hpg_zco    ( kt )      ! z-coordinate
+         CASE (  np_zps )   ;   CALL hpg_zps    ( kt )      ! z-coordinate plus partial steps (interpolation)
+         CASE (  np_sco )   ;   CALL hpg_sco    ( kt )      ! s-coordinate (standard jacobian formulation)
+         CASE (  np_djc )   ;   CALL hpg_djc    ( kt )      ! s-coordinate (Density Jacobian with Cubic polynomial)
+         CASE (  np_prj )   ;   CALL hpg_prj    ( kt )      ! s-coordinate (Pressure Jacobian scheme)
+         CASE (  np_isf )   ;   CALL hpg_isf    ( kt )      ! s-coordinate similar to sco modify for ice shelf
+         END SELECT
+
+         ! calculate the bpc contribution to ua and va
+         z_ua_bpc(:,:,:) = ua(:,:,:) - z_ua(:,:,:)
+         z_va_bpc(:,:,:) = va(:,:,:) - z_va(:,:,:)
+
+         ! calculate the bpc contribution to ua and va at the bottom 
+         DO jj = 2, jpjm1
+            DO ji = 2, jpim1
+               iku = mbku(ji,jj)
+               ikv = mbkv(ji,jj) 
+               z_ua_bpc_bot(ji,jj) = z_ua_bpc(ji,jj,iku)
+               z_va_bpc_bot(ji,jj) = z_va_bpc(ji,jj,ikv)
+            END DO  ! ji
+         END DO ! jj
+
+         ! subtract off the bottom values of bpc contribution to ua and va 
+         DO jk = 1, jpk - 1
+            z_ua_bpc(:,:,jk) = z_ua_bpc(:,:,jk) - z_ua_bpc_bot(:,:)
+            z_va_bpc(:,:,jk) = z_va_bpc(:,:,jk) - z_va_bpc_bot(:,:)
+         END DO 
+
+         ! calculate ua using the original hpg (z_ua) and the bias hpg 
+         ! with the bottom pressure gradients subtracted off 
+         ua(:,:,:) = z_ua(:,:,:) + z_ua_bpc(:,:,:)
+         va(:,:,:) = z_va(:,:,:) + z_va_bpc(:,:,:)
+
+         ! restore original density field
+         rhd(:,:,:) = z_rhd_st(:,:,:)     
+
+         ! deallocate tempory variables
+         DEALLOCATE( z_rhd_st, z_ua, z_va, z_ua_bpc,   &
+            &        z_va_bpc, z_ua_bpc_bot,           &
+            &        z_va_bpc_bot, z_rhd_diff          &
+            &                                          )
+       
+      ENDIF  ! ln_bias .AND. ln_bias_pc_app
+
+
       IF( l_trddyn ) THEN      ! save the hydrostatic pressure gradient trends for momentum trend diagnostics
          ztrdu(:,:,:) = ua(:,:,:) - ztrdu(:,:,:)