C $Header: /home/ubuntu/mnt/e9_copy/MITgcm/verification/hs94.1x64x5/code_ad/ini_theta.F,v 1.1 2003/10/26 01:58:09 heimbach Exp $
C $Name: checkpoint53a_post $

#include "CPP_OPTIONS.h"

CStartOfInterface
      SUBROUTINE INI_THETA( myThid )
C     /==========================================================\
C     | SUBROUTINE INI_THETA                                     |
C     | o Set model initial temperature field.                   |
C     |==========================================================|
C     | There are several options for setting the initial        |
C     | temperature file                                         |
C     |  1. Inline code                                          |
C     |  2. Vertical profile ( uniform T in X and Y )            |
C     |  3. Three-dimensional data from a file. For example from |
C     |     Levitus or from a checkpoint file from a previous    |
C     |     integration.                                         |
C     | In addition to setting the temperature field we also     |
C     | set the initial temperature tendency term here.          |
C     \==========================================================/
      IMPLICIT NONE

C     === Global variables ===
#include "SIZE.h"
#include "EEPARAMS.h"
#include "PARAMS.h"
#include "GRID.h"
#include "DYNVARS.h"

C     == Routine arguments ==
C     myThid -  Number of this instance of INI_THETA
      INTEGER myThid
CEndOfInterface

C     == Local variables ==
C     bi,bj  - Loop counters
C     I,J,K
      INTEGER bi, bj
      INTEGER I, J, K, localWarnings
      _RL     term1,term2,thetaLim,thetaEq
      _RL     thKappa,rSurf
      CHARACTER*(MAX_LEN_MBUF) msgBuf

      _BARRIER

      IF ( hydrogThetaFile .EQ. ' ' ) THEN
C--    Initialise temperature field to Held & Saurez equilibrium theta
       DO bj = myByLo(myThid), myByHi(myThid)
        DO bi = myBxLo(myThid), myBxHi(myThid)
         DO K=1,Nr
          rSurf=1. _d 5
          thKappa = 2. _d 0/7. _d 0
          thetaLim = 200. _d 0 / ((rC(K)/rSurf)**thKappa)
C         thetaLim = 170. _d 0 / ((rC(K)/rSurf)**thKappa)
          DO J=1,sNy
           term1=60. _d 0*(sin(yC(1,J,bi,bj)*deg2rad)**2)
           term2=10. _d 0*log((rC(K)/rSurf))
     &              *(cos(yC(1,J,bi,bj)*deg2rad)**2)
           thetaEq=315. _d 0-term1-term2
           DO I=1,sNx
            theta(I,J,K,bi,bj) = MAX( thetaLim, thetaEq )
C           theta(I,J,K,bi,bj) = tRef(K)
           ENDDO
          ENDDO
         ENDDO
        ENDDO
       ENDDO
      ELSE
       _BEGIN_MASTER( myThid )
       CALL READ_FLD_XYZ_RL( hydrogThetaFile, ' ', theta, 0, myThid )
       _END_MASTER(myThid)
      ENDIF
C     Set initial tendency terms
      localWarnings=0
      DO bj = myByLo(myThid), myByHi(myThid)
       DO bi = myBxLo(myThid), myBxHi(myThid)
        DO K=1,Nr
         DO J=1,sNy
          DO I=1,sNx
           gt   (I,J,K,bi,bj) = 0. _d 0
           gtNM1(I,J,K,bi,bj) = 0. _d 0
           IF (hFacC(I,J,K,bi,bj).EQ.0) theta(I,J,K,bi,bj) = 0.
           IF (hFacC(I,J,K,bi,bj).NE.0.AND.theta(I,J,K,bi,bj).EQ.0.)
     &      THEN
             localWarnings=localWarnings+1
            ENDIF
          ENDDO
         ENDDO
        ENDDO
       ENDDO
      ENDDO
      IF (localWarnings.NE.0) THEN
       WRITE(msgBuf,'(A,A)')
     &  'S/R INI_THETA: theta = 0 identically. If this is intentional',
     &  'you will need to edit ini_theta.F to avoid this safety check'
       CALL PRINT_ERROR( msgBuf , myThid)
       STOP 'ABNORMAL END: S/R INI_THETA'
      ENDIF
C
      _EXCH_XYZ_R8(theta , myThid )
      _EXCH_XYZ_R8(gt , myThid )
      _EXCH_XYZ_R8(gtNM1 , myThid )

      CALL PLOT_FIELD_XYZRL( theta, 'Initial Temperature' , 
     &                       Nr, 1, myThid )

      RETURN
      END