MODULE initrc
   !!======================================================================
   !!                         ***  MODULE initrc  ***
   !! TOP :   Initialisation of passive tracers
   !!======================================================================
   !! History :    -   !  1991-03  ()  original code
   !!             1.0  !  2005-03 (O. Aumont, A. El Moussaoui) F90
   !!              -   !  2005-10 (C. Ethe) print control
   !!             2.0  !  2005-10 (C. Ethe, G. Madec) revised architecture
   !!----------------------------------------------------------------------
#if defined key_top
   !!----------------------------------------------------------------------
   !!   'key_top'                                                TOP models
   !!----------------------------------------------------------------------
   !!   ini_trc    :  initialisation of passive tracers
   !!----------------------------------------------------------------------
   USE oce_trc
   USE trc
   USE trcrst
   USE trcctl
   USE trclec
   USE trcdtr
   USE trcini
   USE prtctl_trc      ! Print control passive tracers (prt_ctl_trc_init routine)
   
   IMPLICIT NONE
   PRIVATE
   
   PUBLIC   ini_trc   ! called by ???

    !! * Substitutions
#  include "domzgr_substitute.h90"
   !!----------------------------------------------------------------------
   !! NEMO/TOP 1.0 , LOCEAN-IPSL (2005) 
   !! $Id$ 
   !! Software governed by the CeCILL licence (modipsl/doc/NEMO_CeCILL.txt)
   !!----------------------------------------------------------------------
  
CONTAINS
   
   SUBROUTINE ini_trc
      !!---------------------------------------------------------------------
      !!                     ***  ROUTINE ini_trc  ***
      !!
      !! ** Purpose :   Initialization of the passive tracer fields 
      !!
      !! ** Method  : - read namelist
      !!              - control the consistancy 
      !!              - compute specific initialisations
      !!              - set initial tracer fields (either read restart 
      !!                or read data or analytical formulation
      !!---------------------------------------------------------------------
      INTEGER ::   jk, jn    ! dummy loop indices
      REAL(wp), DIMENSION(jpi,jpj,jpk) ::   zbt   ! workspace: masked grid volume
      CHARACTER (len=25) :: charout

      !!---------------------------------------------------------------------

      IF(lwp) WRITE(numout,*)
      IF(lwp) WRITE(numout,*) 'ini_trc : initial set up of the passive tracers'
      IF(lwp) WRITE(numout,*) '~~~~~~~'

      !                 ! masked grid volume
      DO jk = 1, jpk
         zbt(:,:,jk) = e1t(:,:) * e2t(:,:) * fse3t(:,:,jk) * tmask(:,:,jk) * tmask_i(:,:)
      END DO
#if defined key_off_degrad
      DO jk = 1, jpk
         zbt(:,:,:) = zbt(:,:,:) * facvol(:,:,jk)      ! degrad option: reduction by facvol
      ENDDO
#endif

      !                 ! total volume of the ocean
      areatot = SUM( zbt(:,:,:) )
      IF( lk_mpp )   CALL mpp_sum( areatot )     ! sum over the global domain  

      CALL trc_lec      ! READ passive tracers namelists

      CALL trc_ctl      ! control consistency between parameters, cpp key and namelists

      CALL trc_ini      ! computes some initializations

      !                 ! set initial tracer values 
      IF( lrsttr ) THEN   ;   CALL trc_rst_read      ! restart from a file
      ELSE                ;   CALL trc_dtr           ! analytical formulation or from data
      ENDIF

      !                 ! Computation content of all tracers
      trai = 0.e0
      DO jn = 1, jptra
         trai = trai + SUM( trn(:,:,:,jn) * zbt(:,:,:) )
      END DO      
      IF( lk_mpp )   CALL mpp_sum( trai )     ! sum over the global domain  


      !                 ! control print
      IF(lwp) WRITE(numout,*) '          *** Total number of passive tracer jptra = ', jptra
      IF(lwp) WRITE(numout,*) '          *** Total volume of ocean                = ', areatot
      IF(lwp) WRITE(numout,*) '          *** Total inital content of all tracers  = ', trai
      IF(lwp) WRITE(numout,*)

      IF( ln_ctl )   CALL prt_ctl_trc_init      ! control print
      !

      IF(ln_ctl) THEN      ! print mean trends (used for debugging)
         WRITE(charout, FMT="('ini ')")
         CALL prt_ctl_trc_info( charout )
         CALL prt_ctl_trc( tab4d=trn, mask=tmask, clinfo=ctrcnm )
      ENDIF

   END SUBROUTINE ini_trc

#else
   !!----------------------------------------------------------------------
   !!  Empty module :                                     No passive tracer
   !!----------------------------------------------------------------------
CONTAINS
   SUBROUTINE ini_trc                      ! Dummy routine   
   END SUBROUTINE ini_trc
#endif

   !!======================================================================
END MODULE initrc