MODULE dynspg
!!======================================================================
!! *** MODULE dynspg ***
!! Ocean dynamics: surface pressure gradient control
!!======================================================================
!! History : 1.0 ! 2005-12 (C. Talandier, G. Madec, V. Garnier) Original code
!! 3.2 ! 2009-07 (R. Benshila) Suppression of rigid-lid option
!!----------------------------------------------------------------------
!!----------------------------------------------------------------------
!! dyn_spg : update the dynamics trend with surface pressure gradient
!! dyn_spg_init: initialization, namelist read, and parameters control
!!----------------------------------------------------------------------
USE oce ! ocean dynamics and tracers variables
USE dom_oce ! ocean space and time domain variables
USE c1d ! 1D vertical configuration
USE phycst ! physical constants
USE sbc_oce ! surface boundary condition: ocean
USE sbcapr ! surface boundary condition: atmospheric pressure
USE dynspg_exp ! surface pressure gradient (dyn_spg_exp routine)
USE dynspg_ts ! surface pressure gradient (dyn_spg_ts routine)
USE sbctide !
USE updtide !
USE trd_oce ! trends: ocean variables
USE trddyn ! trend manager: dynamics
!
USE prtctl ! Print control (prt_ctl routine)
USE in_out_manager ! I/O manager
USE lib_mpp ! MPP library
USE wrk_nemo ! Memory Allocation
USE timing ! Timing
IMPLICIT NONE
PRIVATE
PUBLIC dyn_spg ! routine called by step module
PUBLIC dyn_spg_init ! routine called by opa module
INTEGER :: nspg = 0 ! type of surface pressure gradient scheme defined from lk_dynspg_...
!jth
LOGICAL, PUBLIC :: ln_ulimit
REAL(wp), PUBLIC :: cn_ulimit,cnn_ulimit
!
! ! Parameter to control the surface pressure gradient scheme
INTEGER, PARAMETER :: np_TS = 1 ! split-explicit time stepping (Time-Splitting)
INTEGER, PARAMETER :: np_EXP = 0 ! explicit time stepping
INTEGER, PARAMETER :: np_NO =-1 ! no surface pressure gradient, no scheme
!! * Substitutions
# include "vectopt_loop_substitute.h90"
!!----------------------------------------------------------------------
!! NEMO/OPA 3.2 , LODYC-IPSL (2009)
!! $Id: dynspg.F90 7753 2017-03-03 11:46:59Z mocavero $
!! Software governed by the CeCILL licence (NEMOGCM/NEMO_CeCILL.txt)
!!----------------------------------------------------------------------
CONTAINS
SUBROUTINE dyn_spg( kt )
!!----------------------------------------------------------------------
!! *** ROUTINE dyn_spg ***
!!
!! ** Purpose : compute surface pressure gradient including the
!! atmospheric pressure forcing (ln_apr_dyn=T).
!!
!! ** Method : Two schemes:
!! - explicit : the spg is evaluated at now
!! - split-explicit : a time splitting technique is used
!!
!! ln_apr_dyn=T : the atmospheric pressure forcing is applied
!! as the gradient of the inverse barometer ssh:
!! apgu = - 1/rau0 di[apr] = 0.5*grav di[ssh_ib+ssh_ibb]
!! apgv = - 1/rau0 dj[apr] = 0.5*grav dj[ssh_ib+ssh_ibb]
!! Note that as all external forcing a time averaging over a two rdt
!! period is used to prevent the divergence of odd and even time step.
!!----------------------------------------------------------------------
INTEGER, INTENT(in ) :: kt ! ocean time-step index
!
INTEGER :: ji, jj, jk ! dummy loop indices
REAL(wp) :: z2dt, zg_2, zintp, zgrau0r ! temporary scalar
REAL(wp), POINTER, DIMENSION(:,:,:) :: ztrdu, ztrdv
REAL(wp), POINTER, DIMENSION(:,:) :: zpice
!!----------------------------------------------------------------------
!
IF( nn_timing == 1 ) CALL timing_start('dyn_spg')
!
IF( l_trddyn ) THEN ! temporary save of ta and sa trends
CALL wrk_alloc( jpi,jpj,jpk, ztrdu, ztrdv )
ztrdu(:,:,:) = ua(:,:,:)
ztrdv(:,:,:) = va(:,:,:)
ENDIF
!
IF( ln_apr_dyn & ! atmos. pressure
.OR. ( .NOT.ln_dynspg_ts .AND. (ln_tide_pot .AND. ln_tide) ) & ! tide potential (no time slitting)
.OR. nn_ice_embd == 2 ) THEN ! embedded sea-ice
!
DO jj = 2, jpjm1
DO ji = fs_2, fs_jpim1 ! vector opt.
spgu(ji,jj) = 0._wp
spgv(ji,jj) = 0._wp
END DO
END DO
!
IF( ln_apr_dyn .AND. .NOT.ln_dynspg_ts ) THEN !== Atmospheric pressure gradient (added later in time-split case) ==!
zg_2 = grav * 0.5
DO jj = 2, jpjm1 ! gradient of Patm using inverse barometer ssh
DO ji = fs_2, fs_jpim1 ! vector opt.
spgu(ji,jj) = spgu(ji,jj) + zg_2 * ( ssh_ib (ji+1,jj) - ssh_ib (ji,jj) &
& + ssh_ibb(ji+1,jj) - ssh_ibb(ji,jj) ) * r1_e1u(ji,jj)
spgv(ji,jj) = spgv(ji,jj) + zg_2 * ( ssh_ib (ji,jj+1) - ssh_ib (ji,jj) &
& + ssh_ibb(ji,jj+1) - ssh_ibb(ji,jj) ) * r1_e2v(ji,jj)
END DO
END DO
ENDIF
!
! !== tide potential forcing term ==!
IF( .NOT.ln_dynspg_ts .AND. ( ln_tide_pot .AND. ln_tide ) ) THEN ! N.B. added directly at sub-time-step in ts-case
!
CALL upd_tide( kt ) ! update tide potential
!
DO jj = 2, jpjm1 ! add tide potential forcing
DO ji = fs_2, fs_jpim1 ! vector opt.
spgu(ji,jj) = spgu(ji,jj) + grav * ( pot_astro(ji+1,jj) - pot_astro(ji,jj) ) * r1_e1u(ji,jj)
spgv(ji,jj) = spgv(ji,jj) + grav * ( pot_astro(ji,jj+1) - pot_astro(ji,jj) ) * r1_e2v(ji,jj)
END DO
END DO
ENDIF
!
IF( nn_ice_embd == 2 ) THEN !== embedded sea ice: Pressure gradient due to snow-ice mass ==!
CALL wrk_alloc( jpi,jpj, zpice )
!
zintp = REAL( MOD( kt-1, nn_fsbc ) ) / REAL( nn_fsbc )
zgrau0r = - grav * r1_rau0
zpice(:,:) = ( zintp * snwice_mass(:,:) + ( 1.- zintp ) * snwice_mass_b(:,:) ) * zgrau0r
DO jj = 2, jpjm1
DO ji = fs_2, fs_jpim1 ! vector opt.
spgu(ji,jj) = spgu(ji,jj) + ( zpice(ji+1,jj) - zpice(ji,jj) ) * r1_e1u(ji,jj)
spgv(ji,jj) = spgv(ji,jj) + ( zpice(ji,jj+1) - zpice(ji,jj) ) * r1_e2v(ji,jj)
END DO
END DO
!
CALL wrk_dealloc( jpi,jpj, zpice )
ENDIF
!
DO jk = 1, jpkm1 !== Add all terms to the general trend
DO jj = 2, jpjm1
DO ji = fs_2, fs_jpim1 ! vector opt.
ua(ji,jj,jk) = ua(ji,jj,jk) + spgu(ji,jj)
va(ji,jj,jk) = va(ji,jj,jk) + spgv(ji,jj)
END DO
END DO
END DO
!
!!gm add here a call to dyn_trd for ice pressure gradient, the surf pressure trends ????
!
ENDIF
!
SELECT CASE ( nspg ) !== surface pressure gradient computed and add to the general trend ==!
CASE ( np_EXP ) ; CALL dyn_spg_exp( kt ) ! explicit
CASE ( np_TS ) ; CALL dyn_spg_ts ( kt ) ! time-splitting
END SELECT
!
IF( l_trddyn ) THEN ! save the surface pressure gradient trends for further diagnostics
ztrdu(:,:,:) = ua(:,:,:) - ztrdu(:,:,:)
ztrdv(:,:,:) = va(:,:,:) - ztrdv(:,:,:)
CALL trd_dyn( ztrdu, ztrdv, jpdyn_spg, kt )
CALL wrk_dealloc( jpi,jpj,jpk, ztrdu, ztrdv )
ENDIF
! ! print mean trends (used for debugging)
IF(ln_ctl) CALL prt_ctl( tab3d_1=ua, clinfo1=' spg - Ua: ', mask1=umask, &
& tab3d_2=va, clinfo2= ' Va: ', mask2=vmask, clinfo3='dyn' )
!
IF( nn_timing == 1 ) CALL timing_stop('dyn_spg')
!
END SUBROUTINE dyn_spg
SUBROUTINE dyn_spg_init
!!---------------------------------------------------------------------
!! *** ROUTINE dyn_spg_init ***
!!
!! ** Purpose : Control the consistency between namelist options for
!! surface pressure gradient schemes
!!----------------------------------------------------------------------
INTEGER :: ioptio, ios ! local integers
!
NAMELIST/namdyn_spg/ ln_dynspg_exp , ln_dynspg_ts, &
& ln_bt_fw, ln_bt_av , ln_bt_auto , &
& nn_baro , rn_bt_cmax, nn_bt_flt,ln_ulimit,cn_ulimit,cnn_ulimit
!!----------------------------------------------------------------------
!
IF( nn_timing == 1 ) CALL timing_start('dyn_spg_init')
!
REWIND( numnam_ref ) ! Namelist namdyn_spg in reference namelist : Free surface
READ ( numnam_ref, namdyn_spg, IOSTAT = ios, ERR = 901)
901 IF( ios /= 0 ) CALL ctl_nam ( ios , 'namdyn_spg in reference namelist', lwp )
!
REWIND( numnam_cfg ) ! Namelist namdyn_spg in configuration namelist : Free surface
READ ( numnam_cfg, namdyn_spg, IOSTAT = ios, ERR = 902 )
902 IF( ios /= 0 ) CALL ctl_nam ( ios , 'namdyn_spg in configuration namelist', lwp )
IF(lwm) WRITE ( numond, namdyn_spg )
!
IF(lwp) THEN ! Namelist print
WRITE(numout,*)
WRITE(numout,*) 'dyn_spg_init : choice of the surface pressure gradient scheme'
WRITE(numout,*) '~~~~~~~~~~~'
WRITE(numout,*) ' Explicit free surface ln_dynspg_exp = ', ln_dynspg_exp
WRITE(numout,*) ' Free surface with time splitting ln_dynspg_ts = ', ln_dynspg_ts
write(numout,*) ' Limit velocities ln_ulimit = ',ln_ulimit
write(numout,*) ' Limit velocities max inverse Courant number = ',cn_ulimit
write(numout,*) ' Limit velocities multiplier for divergant flow = ',cnn_ulimit
ENDIF
! ! Control of surface pressure gradient scheme options
nspg = np_NO ; ioptio = 0
IF( ln_dynspg_exp ) THEN ; nspg = np_EXP ; ioptio = ioptio + 1 ; ENDIF
IF( ln_dynspg_ts ) THEN ; nspg = np_TS ; ioptio = ioptio + 1 ; ENDIF
!
IF( ioptio > 1 ) CALL ctl_stop( 'Choose only one surface pressure gradient scheme' )
IF( ioptio == 0 ) CALL ctl_warn( 'NO surface pressure gradient trend in momentum Eqs.' )
IF( ln_dynspg_exp .AND. ln_isfcav ) &
& CALL ctl_stop( ' dynspg_exp not tested with ice shelf cavity ' )
!
IF(lwp) THEN
WRITE(numout,*)
IF( nspg == np_EXP ) WRITE(numout,*) ' ===>> explicit free surface'
IF( nspg == np_TS ) WRITE(numout,*) ' ===>> free surface with time splitting scheme'
IF( nspg == np_NO ) WRITE(numout,*) ' ===>> No surface surface pressure gradient trend in momentum Eqs.'
ENDIF
!
IF( nspg == np_TS ) THEN ! split-explicit scheme initialisation
CALL dyn_spg_ts_init ! do it first: set nn_baro used to allocate some arrays later on
IF( dyn_spg_ts_alloc() /= 0 ) CALL ctl_stop('STOP', 'dyn_spg_init: failed to allocate dynspg_ts arrays' )
IF( neuler/=0 .AND. ln_bt_fw ) CALL ts_rst( nit000, 'READ' )
ENDIF
!
IF( nn_timing == 1 ) CALL timing_stop('dyn_spg_init')
!
END SUBROUTINE dyn_spg_init
!!======================================================================
END MODULE dynspg