SUBROUTINE read_data_GCM(fichnom,timelen, iim_input,jjm_input,ngrid,nslope,vmr_co2_gcm_phys,ps_timeseries, & 
             min_co2_ice,min_h2o_ice,tsurf_ave,tsoil_ave,tsurf_gcm,tsoil_gcm,q_co2,q_h2o,co2_ice_slope, &
             watersurf_density_ave,watersoil_density)

      use netcdf, only: nf90_open,NF90_NOWRITE,nf90_noerr,nf90_strerror, &
                        nf90_get_var, nf90_inq_varid, nf90_inq_dimid, &
                        nf90_inquire_dimension,nf90_close
      use comsoil_h, only: nsoilmx
      USE comsoil_h_PEM, ONLY: soil_pem
      use constants_marspem_mod,only: m_co2,m_noco2
      IMPLICIT NONE

!=======================================================================
!
! Purpose: Read initial confitions file from the GCM
!
! Authors: RV & LL
!=======================================================================

  include "dimensions.h"

!===============================================================================
! Arguments:

  CHARACTER(LEN=*), INTENT(IN) :: fichnom          !--- FILE NAME
  INTEGER, INTENT(IN) :: timelen                   ! number of times stored in the file
  INTEGER :: iim_input,jjm_input,ngrid,nslope      ! number of points in the lat x lon dynamical grid, number of subgrid slopes
! Ouputs
  REAL, INTENT(OUT) ::  min_co2_ice(ngrid,nslope) ! Minimum of co2 ice  per slope of the year [kg/m^2]
  REAL, INTENT(OUT) ::  min_h2o_ice(ngrid,nslope) ! Minimum of h2o ice per slope of the year [kg/m^2]
  REAL, INTENT(OUT)  :: vmr_co2_gcm_phys(ngrid,timelen) ! Physics x Times  co2 volume mixing ratio retrieve from the gcm [m^3/m^3]
  REAL, INTENT(OUT) ::  ps_timeseries(ngrid,timelen)! Surface Pressure [Pa]
  REAL, INTENT(OUT) ::  q_co2(ngrid,timelen)        ! CO2 mass mixing ratio in the first layer [kg/m^3]
  REAL, INTENT(OUT) ::  q_h2o(ngrid,timelen)        ! H2O mass mixing ratio in the first layer [kg/m^3]
  REAL, INTENT(OUT) ::  co2_ice_slope(ngrid,nslope,timelen) ! co2 ice amount per  slope of the year [kg/m^2]
!SOIL
  REAL, INTENT(OUT) ::  tsurf_ave(ngrid,nslope)         ! Average surface temperature of the concatenated file [K]
  REAL, INTENT(OUT) ::  tsoil_ave(ngrid,nsoilmx,nslope) ! Average soil temperature of the concatenated file [K]
  REAL ,INTENT(OUT) ::  tsurf_gcm(ngrid,nslope,timelen)                  ! Surface temperature of the concatenated file, time series [K]
  REAL , INTENT(OUT) ::  tsoil_gcm(ngrid,nsoilmx,nslope,timelen)         ! Soil temperature of the concatenated file, time series [K]
  REAL , INTENT(OUT) ::  watersurf_density_ave(ngrid,nslope)             ! Water density at the surface [kg/m^3]
  REAL , INTENT(OUT) ::  watersoil_density(ngrid,nsoilmx,nslope,timelen) ! Water density in the soil layer, time series [kg/m^3]
!===============================================================================
!   Local Variables 
  CHARACTER(LEN=256) :: msg, var, modname               ! for reading
  INTEGER :: iq, fID, vID, idecal                       ! for reading
  INTEGER :: ierr                                       ! for reading
  CHARACTER(len=12) :: start_file_type="earth" ! default start file type

  REAL,ALLOCATABLE :: time(:) ! times stored in start
  INTEGER :: indextime ! index of selected time

  INTEGER :: edges(4),corner(4)
  INTEGER :: i,j,l,t                                                   ! loop variables
  real  ::  A , B, mmean                                           ! Molar Mass of co2 and no co2, A;B intermediate variables to compute the mean molar mass of the layer

  INTEGER :: islope                                                    ! loop for variables
  CHARACTER*2 :: num                                                   ! for reading sloped variables
  REAL ::  h2o_ice_s_dyn(iim_input+1,jjm_input+1,nslope,timelen)       ! h2o ice per slope of the concatenated file [kg/m^2]
  REAL ::  watercap_slope(iim_input+1,jjm_input+1,nslope,timelen)
  REAL ::  vmr_co2_gcm(iim_input+1,jjm_input+1,timelen)                ! CO2 volume mixing ratio in the first layer  [mol/m^3]
  REAL ::  ps_GCM(iim_input+1,jjm_input+1,timelen)                     ! Surface Pressure [Pa]
  REAL ::  min_co2_ice_dyn(iim_input+1,jjm_input+1,nslope)
  REAL ::  min_h2o_ice_dyn(iim_input+1,jjm_input+1,nslope)
  REAL ::  tsurf_ave_dyn(iim_input+1,jjm_input+1,nslope)               ! Average surface temperature of the concatenated file [K]
  REAL ::  tsoil_ave_dyn(iim_input+1,jjm_input+1,nsoilmx,nslope)       ! Average soil temperature of the concatenated file [K]
  REAL ::  tsurf_gcm_dyn(iim_input+1,jjm_input+1,nslope,timelen)       ! Surface temperature of the concatenated file, time series [K]
  REAL ::  tsoil_gcm_dyn(iim_input+1,jjm_input+1,nsoilmx,nslope,timelen)! Soil temperature of the concatenated file, time series [K]
  REAL ::  q_co2_dyn(iim_input+1,jjm_input+1,timelen)                  ! CO2 mass mixing ratio in the first layer [kg/m^3]
  REAL ::  q_h2o_dyn(iim_input+1,jjm_input+1,timelen)                  ! H2O mass mixing ratio in the first layer [kg/m^3]
  REAL ::  co2_ice_slope_dyn(iim_input+1,jjm_input+1,nslope,timelen)  ! co2 ice amount per  slope of the year [kg/m^2]
  REAL ::  watersurf_density_dyn(iim_input+1,jjm_input+1,nslope,timelen)! Water density at the surface, time series [kg/m^3]
  REAL ::  watersurf_density(ngrid,nslope,timelen)                     ! Water density at the surface, time series [kg/m^3]
  REAL ::  watersoil_density_dyn(iim_input+1,jjm_input+1,nsoilmx,nslope,timelen) ! Water density in the soil layer, time series [kg/m^3]

!-----------------------------------------------------------------------
  modname="read_data_gcm"

      A =(1/m_co2 - 1/m_noco2)
      B=1/m_noco2

  write(*,*) "Opening ", fichnom, "..."

!  Open initial state NetCDF file
  var=fichnom
  CALL err(NF90_OPEN(var,NF90_NOWRITE,fID),"open",var)

     write(*,*) "Downloading data for vmr co2..."

  CALL get_var3("co2_layer1"   ,q_co2_dyn)

     write(*,*) "Downloading data for vmr co2 done"
     write(*,*) "Downloading data for vmr h20..."

  CALL get_var3("h2o_layer1"   ,q_h2o_dyn)

     write(*,*) "Downloading data for vmr h2o done"
     write(*,*) "Downloading data for surface pressure ..."

  CALL get_var3("ps"   ,ps_GCM)

     write(*,*) "Downloading data for surface pressure done"
     write(*,*) "nslope=", nslope

if(nslope.gt.1) then

     write(*,*) "Downloading data for co2ice_slope ..."

DO islope=1,nslope
  write(num,fmt='(i2.2)') islope
  call get_var3("co2ice_slope"//num,co2_ice_slope_dyn(:,:,islope,:))
ENDDO

     write(*,*) "Downloading data for co2ice_slope done"
     write(*,*) "Downloading data for h2o_ice_s_slope ..."

DO islope=1,nslope
  write(num,fmt='(i2.2)') islope
  call get_var3("h2o_ice_s_slope"//num,h2o_ice_s_dyn(:,:,islope,:))
ENDDO

     write(*,*) "Downloading data for h2o_ice_s_slope done"

#ifndef CPP_STD

     write(*,*) "Downloading data for watercap_slope ..."
DO islope=1,nslope
       write(num,fmt='(i2.2)') islope
       call get_var3("watercap_slope"//num,watercap_slope(:,:,islope,:))
!        watercap_slope(:,:,:,:)= 0.
ENDDO            
     write(*,*) "Downloading data for watercap_slope done"

#endif
    
 write(*,*) "Downloading data for tsurf_slope ..."

DO islope=1,nslope
  write(num,fmt='(i2.2)') islope
  call get_var3("tsurf_slope"//num,tsurf_gcm_dyn(:,:,islope,:))
ENDDO

     write(*,*) "Downloading data for tsurf_slope done"

#ifndef CPP_STD

     if(soil_pem) then

     write(*,*) "Downloading data for soiltemp_slope ..."

DO islope=1,nslope
  write(num,fmt='(i2.2)') islope
  call get_var4("soiltemp_slope"//num,tsoil_gcm_dyn(:,:,:,islope,:))
ENDDO

     write(*,*) "Downloading data for soiltemp_slope done"

     write(*,*) "Downloading data for watersoil_density ..."

DO islope=1,nslope
  write(num,fmt='(i2.2)') islope
  call get_var4("Waterdensity_soil_slope"//num,watersoil_density_dyn(:,:,:,islope,:))
ENDDO

     write(*,*) "Downloading data for  watersoil_density  done"

     write(*,*) "Downloading data for  watersurf_density  ..."

DO islope=1,nslope
  write(num,fmt='(i2.2)') islope
  call get_var3("Waterdensity_surface"//num,watersurf_density_dyn(:,:,islope,:))
ENDDO

     write(*,*) "Downloading data for  watersurf_density  done"

  endif !soil_pem

#endif

  else !nslope=1 no slope, we copy all the values

    CALL get_var3("h2o_ice_s", h2o_ice_s_dyn(:,:,1,:))
    CALL get_var3("co2ice", co2_ice_slope_dyn(:,:,1,:))
    call get_var3("tsurf", tsurf_gcm_dyn(:,:,1,:))
#ifndef CPP_STD
!    call get_var3("watercap", watercap_slope(:,:,1,:))
  watercap_slope(:,:,1,:)=0.
  watersurf_density_dyn(:,:,:,:)=0.
  watersoil_density_dyn(:,:,:,:,:)=0.
#endif

    if(soil_pem) then
      call get_var4("soiltemp",tsoil_gcm_dyn(:,:,:,1,:))
    endif !soil_pem
  endif !nslope=1

! Compute the minimum over the year for each point
  write(*,*) "Computing the min of h2o_ice_slope"
  min_h2o_ice_dyn(:,:,:)=minval(h2o_ice_s_dyn+watercap_slope,4)
  write(*,*) "Computing the min of co2_ice_slope"
  min_co2_ice_dyn(:,:,:)=minval(co2_ice_slope_dyn,4)

!Compute averages

    write(*,*) "Computing average of tsurf"
    tsurf_ave_dyn(:,:,:)=SUM(tsurf_gcm_dyn(:,:,:,:),4)/timelen

#ifndef CPP_1D
  DO islope = 1,nslope
    DO t=1,timelen
      CALL gr_dyn_fi(1,iim_input+1,jjm_input+1,ngrid,watersurf_density_dyn(:,:,islope,t),watersurf_density(:,islope,t))
    ENDDO
  ENDDO
#endif

  if(soil_pem) then
    write(*,*) "Computing average of tsoil"
    tsoil_ave_dyn(:,:,:,:)=SUM(tsoil_gcm_dyn(:,:,:,:,:),5)/timelen
    write(*,*) "Computing average of watersurf_density"
    watersurf_density_ave(:,:) = SUM(watersurf_density(:,:,:),3)/timelen
  endif

! By definition, a density is positive, we get rid of the negative values
  DO i=1,iim+1
    DO j = 1, jjm_input+1
       DO islope=1,nslope
          if (min_co2_ice_dyn(i,j,islope).LT.0) then
            min_co2_ice_dyn(i,j,islope)  = 0.
          endif
          if (min_h2o_ice_dyn(i,j,islope).LT.0) then
            min_h2o_ice_dyn(i,j,islope)  = 0.
          endif
       ENDDO
    ENDDO
  ENDDO

  DO i=1,iim+1
    DO j = 1, jjm_input+1
      DO t = 1, timelen
         if (q_co2_dyn(i,j,t).LT.0) then
              q_co2_dyn(i,j,t)=1E-10
         elseif (q_co2_dyn(i,j,t).GT.1) then
              q_co2_dyn(i,j,t)=1.
         endif
         if (q_h2o_dyn(i,j,t).LT.0) then
              q_h2o_dyn(i,j,t)=1E-30
         elseif (q_h2o_dyn(i,j,t).GT.1) then
              q_h2o_dyn(i,j,t)=1.
         endif
         mmean=1/(A*q_co2_dyn(i,j,t) +B)
         vmr_co2_gcm(i,j,t) = q_co2_dyn(i,j,t)*mmean/m_co2
      ENDDO
    ENDDO
  ENDDO

#ifndef CPP_1D

     CALL gr_dyn_fi(timelen,iim_input+1,jjm_input+1,ngrid,vmr_co2_gcm,vmr_co2_gcm_phys)
     call gr_dyn_fi(timelen,iim_input+1,jjm_input+1,ngrid,ps_GCM,ps_timeseries)
     CALL gr_dyn_fi(timelen,iim_input+1,jjm_input+1,ngrid,q_co2_dyn,q_co2)
     CALL gr_dyn_fi(timelen,iim_input+1,jjm_input+1,ngrid,q_h2o_dyn,q_h2o)

     DO islope = 1,nslope
       CALL gr_dyn_fi(1,iim_input+1,jjm_input+1,ngrid,min_co2_ice_dyn(:,:,islope),min_co2_ice(:,islope))
       CALL gr_dyn_fi(1,iim_input+1,jjm_input+1,ngrid,min_h2o_ice_dyn(:,:,islope),min_h2o_ice(:,islope))
       if(soil_pem) then
       DO l=1,nsoilmx
         CALL gr_dyn_fi(1,iim_input+1,jjm_input+1,ngrid,tsoil_ave_dyn(:,:,l,islope),tsoil_ave(:,l,islope))
         DO t=1,timelen
           CALL gr_dyn_fi(1,iim_input+1,jjm_input+1,ngrid,tsoil_gcm_dyn(:,:,l,islope,t),tsoil_gcm(:,l,islope,t))
           CALL gr_dyn_fi(1,iim_input+1,jjm_input+1,ngrid,watersoil_density_dyn(:,:,l,islope,t),watersoil_density(:,l,islope,t))
         ENDDO
       ENDDO
       endif !soil_pem
       DO t=1,timelen
         CALL gr_dyn_fi(1,iim_input+1,jjm_input+1,ngrid,tsurf_GCM_dyn(:,:,islope,t),tsurf_GCM(:,islope,t))
         CALL gr_dyn_fi(1,iim_input+1,jjm_input+1,ngrid,co2_ice_slope_dyn(:,:,islope,t),co2_ice_slope(:,islope,t))
       ENDDO
     ENDDO

     CALL gr_dyn_fi(nslope,iim_input+1,jjm_input+1,ngrid,tsurf_ave_dyn,tsurf_ave)

#else

  vmr_co2_gcm_phys(1,:)=vmr_co2_gcm(1,1,:)
  ps_timeseries(1,:)=ps_GCM(1,1,:)
  q_co2(1,:)=q_co2_dyn(1,1,:)
  q_h2o(1,:)=q_h2o_dyn(1,1,:)
  min_co2_ice(1,:)=min_co2_ice_dyn(1,1,:)
  min_h2o_ice(1,:)=min_h2o_ice_dyn(1,1,:)
  if(soil_pem) then
    tsoil_ave(1,:,:)=tsoil_ave_dyn(1,1,:,:)
    tsoil_gcm(1,:,:,:)=tsoil_gcm_dyn(1,1,:,:,:)
    watersoil_density(1,:,:,:)=watersoil_density_dyn(1,1,:,:,:)
  endif !soil_pem
  tsurf_GCM(1,:,:)=tsurf_GCM_dyn(1,1,:,:)
  co2_ice_slope(1,:,:)=co2_ice_slope_dyn(1,1,:,:)
  tsurf_ave(1,:)=tsurf_ave_dyn(1,1,:)

#endif

  CONTAINS

SUBROUTINE check_dim(n1,n2,str1,str2)
  INTEGER,          INTENT(IN) :: n1, n2
  CHARACTER(LEN=*), INTENT(IN) :: str1, str2
  CHARACTER(LEN=256) :: s1, s2
  IF(n1/=n2) THEN
    s1='value of '//TRIM(str1)//' ='
    s2=' read in starting file differs from parametrized '//TRIM(str2)//' ='
    WRITE(msg,'(10x,a,i4,2x,a,i4)')TRIM(s1),n1,TRIM(s2),n2
    CALL ABORT_gcm(TRIM(modname),TRIM(msg),1)
  END IF
END SUBROUTINE check_dim


SUBROUTINE get_var1(var,v)
  CHARACTER(LEN=*), INTENT(IN)  :: var
  REAL,             INTENT(OUT) :: v(:)
  CALL err(NF90_INQ_VARID(fID,var,vID),"inq",var)
  CALL err(NF90_GET_VAR(fID,vID,v),"get",var)
END SUBROUTINE get_var1


SUBROUTINE get_var3(var,v) ! on U grid
  CHARACTER(LEN=*), INTENT(IN)  :: var
  REAL,             INTENT(OUT) :: v(:,:,:)
  CALL err(NF90_INQ_VARID(fID,var,vID),"inq",var)
  CALL err(NF90_GET_VAR(fID,vID,v),"get",var)

END SUBROUTINE get_var3

SUBROUTINE get_var4(var,v) 
  CHARACTER(LEN=*), INTENT(IN)  :: var
  REAL,             INTENT(OUT) :: v(:,:,:,:)
  CALL err(NF90_INQ_VARID(fID,var,vID),"inq",var)
  CALL err(NF90_GET_VAR(fID,vID,v),"get",var)
END SUBROUTINE get_var4

SUBROUTINE err(ierr,typ,nam)
  INTEGER,          INTENT(IN) :: ierr   !--- NetCDF ERROR CODE
  CHARACTER(LEN=*), INTENT(IN) :: typ    !--- TYPE OF OPERATION
  CHARACTER(LEN=*), INTENT(IN) :: nam    !--- FIELD/FILE NAME
  IF(ierr==NF90_NoERR) RETURN
  SELECT CASE(typ)
    CASE('inq');   msg="Field <"//TRIM(nam)//"> is missing"
    CASE('get');   msg="Reading failed for <"//TRIM(nam)//">"
    CASE('open');  msg="File opening failed for <"//TRIM(nam)//">"
    CASE('close'); msg="File closing failed for <"//TRIM(nam)//">"
  END SELECT
  CALL ABORT_gcm(TRIM(modname),TRIM(msg),ierr)
END SUBROUTINE err

END SUBROUTINE read_data_gcm