
! $Id: alpale_th.F90 5099 2024-07-22 19:29:09Z abarral $

SUBROUTINE alpale_th ( dtime, lmax_th, t_seri, cell_area,  &
                       cin, s2, n2, strig,  &
                       ale_bl_trig, ale_bl_stat, ale_bl,  &
                       alp_bl, alp_bl_stat, &
                       proba_notrig, random_notrig, birth_rate)

! **************************************************************
! *
! ALPALE_TH                                                    *
! *
! *
! written by   : Jean-Yves Grandpeix, 11/05/2016              *
! modified by :                                               *
! **************************************************************

  USE dimphy
  USE ioipsl_getin_p_mod, ONLY : getin_p
  USE print_control_mod, ONLY: mydebug=>debug , lunout, prt_level

  IMPLICIT NONE

!================================================================
! Auteur(s)   : Jean-Yves Grandpeix, 11/05/2016
! Objet : Contribution of the thermal scheme to Ale and Alp
!================================================================

! Input arguments
!----------------
  REAL, INTENT(IN)                                           :: dtime
  REAL, DIMENSION(klon), INTENT(IN)                          :: cell_area
  INTEGER, DIMENSION(klon), INTENT(IN)                       :: lmax_th
  REAL, DIMENSION(klon,klev), INTENT(IN)                     :: t_seri
  REAL, DIMENSION(klon), INTENT(IN)                          :: ale_bl_stat
  REAL, DIMENSION(klon), INTENT(IN)                          :: cin
  REAL, DIMENSION(klon), INTENT(IN)                          :: s2, n2, strig
                                                                
  REAL, DIMENSION(klon), INTENT(INOUT)                       :: ale_bl_trig, ale_bl
  REAL, DIMENSION(klon), INTENT(INOUT)                       :: alp_bl
  REAL, DIMENSION(klon), INTENT(INOUT)                       :: alp_bl_stat
  REAL, DIMENSION(klon), INTENT(INOUT)                       :: proba_notrig

  REAL, DIMENSION(klon), INTENT(OUT)                         :: random_notrig

  REAL, DIMENSION(klon), INTENT(OUT)                         :: birth_rate

  include "alpale.h"

! Local variables
!----------------
  INTEGER                                                    :: i
  LOGICAL, SAVE                                              :: first = .TRUE.
  LOGICAL, SAVE                                              :: multiply_proba_notrig = .FALSE.
  REAL, SAVE                                                 :: random_notrig_max=1.
  REAL, SAVE                                                 :: cv_feed_area
  REAL                                                       :: birth_number
  REAL, DIMENSION(klon)                                      :: ale_bl_ref
  REAL, DIMENSION(klon)                                      :: tau_trig

    !$OMP THREADPRIVATE(multiply_proba_notrig) 
    !$OMP THREADPRIVATE(random_notrig_max) 
    !$OMP THREADPRIVATE(cv_feed_area) 
    !$OMP THREADPRIVATE(first)

 REAL umexp  ! expression of (1.-exp(-x))/x valid for all x, especially when x->0
 REAL x

     CHARACTER (LEN=20) :: modname='alpale_th'
     CHARACTER (LEN=80) :: abort_message
     
 umexp(x) = max(sign(1.,x-1.e-3),0.)*(1.-exp(-x))/max(x,1.e-3) + &
            (1.-max(sign(1.,x-1.e-3),0.))*(1.-0.5*x*(1.-x/3.*(1.-0.25*x)))  !!! correct formula            (jyg)
!!!            (1.-max(sign(1.,x-1.e-3),0.))*(-0.5*x*(1.-x/3.*(1.-0.25*x))) !!! bug introduced by mistake  (jyg)
!!!            (1.-max(sign(1.,x-1.e-3),0.))*(1.-0.5*x*(1.-x/3.*(1.-0.25*x)))  !!! initial correct formula (jyg)

!+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
!  JYG, 20160513 : Introduction of the Effective Lifting Power (ELP), which 
! takes into account the area (cv_feed_area) covered by thermals contributing 
! to each cumulonimbus.
!   The use of ELP prevents singularities when the trigger probability tends to
! zero. It is activated by iflag_clos_bl = 3.
!   The ELP values are stored in the ALP_bl variable.

!+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

    IF (first) THEN
      CALL getin_p('multiply_proba_notrig',multiply_proba_notrig)
      IF (iflag_clos_bl < 3) THEN
         random_notrig_max=1.
         CALL getin_p('random_notrig_max',random_notrig_max)
      ELSEIF (iflag_clos_bl == 3) THEN  ! (iflag_clos_bl .LT. 3)
         cv_feed_area = 1.e10   ! m2
         CALL getin_p('cv_feed_area', cv_feed_area)
      ENDIF  !! (iflag_clos_bl .LT. 3)
      first=.FALSE.
    ENDIF

!!
!!   Control of the multiplication of no-trigger probabilities between calls 
!! to the convection scheme. If multiply_proba_notrig is .false., then
!! proba_notrig is set to 1 at each call to alpale_th, so that only the last call 
!! plays a role in the triggering of convection. If it is .true., then propa_notrig 
!! is saved between calls to convection and is reset to 1 only after calling the 
!! convection scheme.
!!    For instance, if the probability of no_trigger is 0.9 at each call, and if 
!! there are 3 calls to alpale_th between calls to the convection scheme, then the 
!! probability of triggering convection will be 0.1 (= 1.-0.9) if 
!! multiply_proba_notrig is .false. and 0.271 (= 1.-0.9^3) if multiply_proba_notrig 
!! is .true.
!!
    IF (.NOT.multiply_proba_notrig) THEN
             DO i=1,klon
                proba_notrig(i)=1.
             ENDDO
    ENDIF  !! (.NOT.multiply_proba_notrig)
!!
!!
!---------------------------------------
  IF (iflag_clos_bl < 3) THEN
!---------------------------------------

!      Original code (Nicolas Rochetin)
!     --------------------------------
          !cc nrlmd le 10/04/2012
          !-----------Stochastic triggering-----------
          if (iflag_trig_bl>=1) then

             IF (prt_level >= 10) THEN
                WRITE(lunout,*)'cin, ale_bl_stat, alp_bl, alp_bl_stat ', &
                     cin, ale_bl_stat, alp_bl, alp_bl_stat
             ENDIF


             !----Initialisations
             do i=1,klon
!!jyg                proba_notrig(i)=1.
                random_notrig(i)=1e6*ale_bl_stat(i)-int(1e6*ale_bl_stat(i))
                if ( random_notrig(i) > random_notrig_max ) random_notrig(i)=0.
                if ( ale_bl_trig(i) < abs(cin(i))+1.e-10 ) then
                   tau_trig(i)=tau_trig_shallow
                else
                   tau_trig(i)=tau_trig_deep
                endif
             enddo

             IF (prt_level >= 10) THEN
                WRITE(lunout,*)'random_notrig, tau_trig ', &
                     random_notrig, tau_trig
                WRITE(lunout,*)'s_trig,s2,n2 ', &
                     s_trig,s2,n2
             ENDIF

             !Option pour re-activer l'ancien calcul de Ale_bl (iflag_trig_bl=2)
             IF (iflag_trig_bl==1) then

                !----Tirage al\'eatoire et calcul de ale_bl_trig
                do i=1,klon
                   if ( (ale_bl_stat(i) > abs(cin(i))+1.e-10) )  then
                      proba_notrig(i)=proba_notrig(i)* &
                         (1.-exp(-strig(i)/s2(i)))**(n2(i)*dtime/tau_trig(i))
                      !        print *, 'proba_notrig(i) ',proba_notrig(i)
                      if (random_notrig(i) >= proba_notrig(i)) then
                         ale_bl_trig(i)=ale_bl_stat(i)
                      else
                         ale_bl_trig(i)=0.
                      endif
                      birth_rate(i) = n2(i)*exp(-strig(i)/s2(i))/(tau_trig(i)*cell_area(i))
!!!                      birth_rate(i) = max(birth_rate(i),1.e-18)
                   else
!!jyg                      proba_notrig(i)=1.
                      birth_rate(i) = 0.
                      random_notrig(i)=0.
                      ale_bl_trig(i)=0.
                   endif
                enddo

             ELSE IF (iflag_trig_bl>=2) then

                do i=1,klon
                   if ( (Ale_bl(i) > abs(cin(i))+1.e-10) )  then
                      proba_notrig(i)=proba_notrig(i)* &
                         (1.-exp(-strig(i)/s2(i)))**(n2(i)*dtime/tau_trig(i))
                      !        print *, 'proba_notrig(i) ',proba_notrig(i)
                      if (random_notrig(i) >= proba_notrig(i)) then
                         ale_bl_trig(i)=Ale_bl(i)
                      else
                         ale_bl_trig(i)=0.
                      endif
                      birth_rate(i) = n2(i)*exp(-strig(i)/s2(i))/(tau_trig(i)*cell_area(i))
!!!                      birth_rate(i) = max(birth_rate(i),1.e-18)
                   else
!!jyg                      proba_notrig(i)=1.
                      birth_rate(i) = 0.
                      random_notrig(i)=0.
                      ale_bl_trig(i)=0.
                   endif
                enddo

             ENDIF

             IF (prt_level >= 10) THEN
                WRITE(lunout,*)'proba_notrig, ale_bl_trig ', &
                     proba_notrig, ale_bl_trig
             ENDIF

          endif !(iflag_trig_bl)

          !-----------Statistical closure-----------
          if (iflag_clos_bl==1) then

             do i=1,klon
                !CR: alp probabiliste
                if (ale_bl_trig(i)>0.) then
                   alp_bl(i)=alp_bl(i)/(1.-min(proba_notrig(i),0.999))
                endif
             enddo

          else if (iflag_clos_bl==2) then

             !CR: alp calculee dans thermcell_main
             do i=1,klon
                alp_bl(i)=alp_bl_stat(i)
             enddo

          else

             alp_bl_stat(:)=0.

          endif !(iflag_clos_bl)

!---------------------------------------
  ELSEIF (iflag_clos_bl == 3) THEN  ! (iflag_clos_bl .LT. 3)
!---------------------------------------

!      New code with Effective Lifting Power
!     -------------------------------------

          !-----------Stochastic triggering-----------
     if (iflag_trig_bl>=1) then

        IF (prt_level >= 10) THEN
           WRITE(lunout,*)'cin, ale_bl_stat, alp_bl_stat ', &
                cin, ale_bl_stat, alp_bl_stat
        ENDIF

        ! Use ale_bl_stat (Rochetin's code) or ale_bl (old code) according to 
        ! iflag_trig_bl value.
        IF (iflag_trig_bl==1) then         ! use ale_bl_stat (Rochetin computation)
         do i=1,klon
              ale_bl_ref(i)=ale_bl_stat(i)
         enddo
        ELSE IF (iflag_trig_bl>=2) then    ! use ale_bl (old computation)
         do i=1,klon
              ale_bl_ref(i)=Ale_bl(i)
         enddo
        ENDIF ! (iflag_trig_bl.eq.1)


        !----Initializations and random number generation
        do i=1,klon
!!jyg           proba_notrig(i)=1.
           random_notrig(i)=1e6*ale_bl_stat(i)-int(1e6*ale_bl_stat(i))
           if ( ale_bl_trig(i) < abs(cin(i))+1.e-10 ) then
              tau_trig(i)=tau_trig_shallow
           else
              tau_trig(i)=tau_trig_deep
           endif
        enddo

        IF (prt_level >= 10) THEN
           WRITE(lunout,*)'random_notrig, tau_trig ', &
                random_notrig, tau_trig
           WRITE(lunout,*)'s_trig,s2,n2 ', &
                s_trig,s2,n2
        ENDIF

        !----alp_bl computation
        do i=1,klon
           if ( (ale_bl_ref(i) > abs(cin(i))+1.e-10) )  then
              birth_number = n2(i)*exp(-strig(i)/s2(i))
              birth_rate(i) = birth_number/(tau_trig(i)*cell_area(i))
!!!              birth_rate(i) = max(birth_rate(i),1.e-18)
              proba_notrig(i)=proba_notrig(i)*exp(-birth_number*dtime/tau_trig(i))
              Alp_bl(i) = Alp_bl(i)* &
                          umexp(-birth_number*cv_feed_area/cell_area(i))/ &
                          umexp(-birth_number*dtime/tau_trig(i))*  &
                          tau_trig(i)*cv_feed_area/(dtime*cell_area(i))
          else 
!!jyg              proba_notrig(i)=1.
              birth_rate(i)=0.
              random_notrig(i)=0.
              alp_bl(i)=0.
           endif
        enddo

        !----ale_bl_trig computation
         do i=1,klon
           if (random_notrig(i) >= proba_notrig(i)) then
              ale_bl_trig(i)=ale_bl_ref(i)
           else
              ale_bl_trig(i)=0.
           endif
         enddo

        IF (prt_level >= 10) THEN
           WRITE(lunout,*)'proba_notrig, ale_bl_trig ', &
                proba_notrig, ale_bl_trig
        ENDIF

     endif !(iflag_trig_bl .ge. 1)

!---------------------------------------
  ENDIF ! (iflag_clos_bl .LT. 3)
!---------------------------------------

          IF (prt_level >= 10) THEN
             WRITE(lunout,*)'alpale_th: ale_bl_trig, alp_bl_stat, birth_rate ', &
                      ale_bl_trig(1), alp_bl_stat(1), birth_rate(1)
          ENDIF

          !cc fin nrlmd le 10/04/2012

          !IM/FH: 2011/02/23 
          ! Couplage Thermiques/Emanuel seulement si T<0
          if (iflag_coupl==2) then
             IF (prt_level >= 10) THEN
                WRITE(lunout,*)'Couplage Thermiques/Emanuel seulement si T<0'
             ENDIF
             do i=1,klon
                if (t_seri(i,lmax_th(i))>273.) then
                   Ale_bl(i)=0.
                endif
             enddo
!    print *,'In order to run with iflag_coupl=2, you have to comment out the following stop'
!             STOP
             abort_message='In order to run with iflag_coupl=2, you have to comment out the following abort'
             CALL abort_physic(modname,abort_message,1)
          endif
   RETURN
   END

