C $Header: /home/ubuntu/mnt/e9_copy/MITgcm/pkg/aim_v23/aim_do_physics.F,v 1.8 2004/06/24 23:43:11 jmc Exp $
C $Name:  $

#include "AIM_OPTIONS.h"

CBOP
C     !ROUTINE: AIM_DO_PHYSICS
C     !INTERFACE:
      SUBROUTINE AIM_DO_PHYSICS( bi, bj, myTime, myIter, myThid ) 
                                      
C     !DESCRIPTION: \bv
C     *==================================================================*
C     | S/R AIM_DO_PHYSICS
C     *==================================================================*
C     | Interface between atmospheric physics package and the
C     | dynamical model.
C     | Routine calls physics pacakge after setting surface BC.
C     | Package should derive and set tendency terms
C     | which can be included as external forcing terms in the dynamical
C     | tendency routines. Packages should communicate this information
C     | through common blocks.
C     *==================================================================*
C     \ev

C     !USES:
      IMPLICIT NONE

C     -------------- Global variables ------------------------------------
C-- size for MITgcm & Physics package :
#include "AIM_SIZE.h"

C-- MITgcm
#include "EEPARAMS.h"
#include "PARAMS.h"
#include "DYNVARS.h"
#include "GRID.h"
#include "SURFACE.h"

C-- Physics package
#include "AIM_PARAMS.h"
#include "AIM_FFIELDS.h"
#include "AIM_GRID.h"
#include "com_physvar.h"
#include "com_forcing.h"

C     !INPUT/OUTPUT PARAMETERS:
C     == Routine arguments ==
C     bi,bj  - Tile index 
C     myTime - Current time of simulation ( s )
C     myIter - Current iteration number in simulation
C     myThid - Number of this instance of the routine
      INTEGER bi, bj, myIter, myThid
      _RL myTime
CEOP

#ifdef ALLOW_AIM
C     == Local variables ==
C     I,J,K,I2      - Loop counters
C     tYear         - Fraction into year
C     Katm          - Atmospheric K index
C     prcAtm   :: total precip from the atmosphere [kg/m2/s]
C     evpAtm   :: evaporation to the atmosphere [kg/m2/s] (>0 if evaporate)
C     flxSW    :: net Short-Wave heat flux into the ocean (+=down) [W/m2]
      INTEGER I,J,K,I2
c     INTEGER Katm
      _RL     tYear, yearLength
      _RL prcAtm(1-OLx:sNx+OLx,1-OLy:sNy+OLy)
      _RL evpAtm(1-OLx:sNx+OLx,1-OLy:sNy+OLy)
      _RL flxSW (1-OLx:sNx+OLx,1-OLy:sNy+OLy)

C_jmc: Because AIM physics LSC is not applied in the stratosphere (top level),
C      ==> move water wapor from the stratos to the surface level.
      DO j = 1-Oly, sNy+Oly
       DO i = 1-Olx, sNx+Olx
        k = ksurfC(i,j,bi,bj)
        IF (k.LE.Nr)
     &    salt(i,j,k,bi,bj) = salt(i,j,k,bi,bj)
     &                      + salt(i,j,Nr,bi,bj)*drF(Nr)*recip_drF(k)
     &                  *hFacC(i,j,Nr,bi,bj)*recip_hFacC(i,j,k,bi,bj)
        salt(i,j,Nr,bi,bj) = 0.
       ENDDO
      ENDDO

C---+----1----+----2----+----3----+----4----+----5----+----6----+----7-|--+----|

C-    Physics package needs to know time of year as a fraction
      yearLength = 86400.*360.
      tYear = mod(myTime/yearLength, 1. _d 0)
c     tYear = myTime/(86400.*360.) -
c    &        FLOAT(INT(myTime/(86400.*360.)))

C--   Set surface Boundary Conditions for atmos. physics package:
C     (Albedo, Soil moisture, Surf Temp, Land sea mask)
C     includes some parts of S/R FORDATE from F.Molteni SPEDDY code (ver23)
      CALL AIM_SURF_BC( tYear, myTime, myIter, bi, bj, myThid )

C--   Set surface geopotential: (g * orographic height)
      DO J=1,sNy
       DO I=1,sNx
         I2 = I+(J-1)*sNx
         PHI0(I2) = gravity*topoZ(i,j,bi,bj)
       ENDDO
      ENDDO

C--   Set topographic dependent FOROG var (originally in common SFLFIX);
C      used to compute for wind stress over land

c_FM  IF (IDAY.EQ.0) THEN
c_FM    CALL SFLSET (PHIS0)
        CALL SFLSET (PHI0, fOrogr(1,myThid), bi,bj,myThid)
c_FM  ENDIF
c_FM  CALL SOL_OZ (SOLC,TYEAR)

C---+----1----+----2----+----3----+----4----+----5----+----6----+----7-|--+----|

C-    Compute atmospheric-physics tendencies (call the main AIM S/R)
      CALL PHY_DRIVER( tYear, myTime, myIter, bi, bj, myThid )

      CALL AIM_AIM2DYN( bi, bj, myTime, myIter, myThid )

#ifdef ALLOW_LAND
      IF (useLand) THEN
C-    prepare Surface flux over land for land package
        CALL AIM_AIM2LAND( aim_landFr, bi, bj, 
     I                     myTime, myIter, myThid )

C-    Step forward land model
        CALL LAND_STEPFWD( aim_landFr, bi, bj, 
     I                     myTime, myIter, myThid )

C-    Land diagnostics : write snap-shot & cumulate for TimeAve output
      CALL LAND_DIAGNOSTICS( aim_landFr, bi, bj, 
     I                       myTime, myIter, myThid )

      ENDIF
#endif /* ALLOW_LAND */

C-    surface fluxes over ocean (ice-free & ice covered) 
C       used for diagnostics, thsice package and coupler
        CALL AIM_AIM2SIOCE( aim_landFr, fmask1(1,3,myThid),
     O                      prcAtm, evpAtm, flxSW, 
     I                      bi, bj, myTime, myIter, myThid )

#ifdef ALLOW_THSICE
      IF ( useThSIce ) THEN

C-    Step forward sea-ice model
        CALL THSICE_STEP_FWD( bi, bj, 1, sNx, 1, sNy,
     I                        prcAtm, 
     U                        evpAtm, flxSW,
     I                        myTime, myIter, myThid )

C-    Slab Ocean : step forward ocean mixed-layer temp. & salinity 
        CALL THSICE_SLAB_OCEAN( 
     O                         dTsurf(1,2,myThid), 
     I                         bi,bj, myThid )

        CALL THSICE_AVE( evpAtm, flxSW,
     I                   bi, bj, myTime, myIter, myThid )

      ENDIF
#endif /* ALLOW_THSICE */

#ifdef COMPONENT_MODULE
      IF ( useCoupler ) THEN
        CALL ATM_STORE_MY_DATA( bi, bj, myIter, myTime, myThid )
      ENDIF
#endif /* COMPONENT_MODULE */

C-    AIM diagnostics : write snap-shot & cumulate for TimeAve output
      CALL AIM_DIAGNOSTICS( bi, bj, myTime, myIter, myThid )

#endif /* ALLOW_AIM */

      RETURN
      END