MODULE limit

  !*******************************************************************************
  ! Author : L. Fairhead, 27/01/94
  !-------------------------------------------------------------------------------
  ! Purpose: Boundary conditions files building for new model using climatologies.
  !          Both grids have to be regular.
  !-------------------------------------------------------------------------------
  ! Note: This routine is designed to work for Earth
  !-------------------------------------------------------------------------------
  ! Modification history:
  !  * 23/03/1994: Z. X. Li
  !  *    09/1999: L. Fairhead (netcdf reading in LMDZ.3.3)
  !  *    07/2001: P. Le Van
  !  *    11/2009: L. Guez     (ozone day & night climatos, see etat0_netcdf.F90)
  !  *    12/2009: D. Cugnet   (f77->f90, calendars, files from coupled runs)
  !-------------------------------------------------------------------------------

  USE ioipsl, ONLY: flininfo, flinopen, flinget, flinclo
  USE lmdz_assert_eq, ONLY: assert_eq
  USE cal_tools_m, ONLY: year_len, mid_month
  USE conf_dat_m, ONLY: conf_dat2d, conf_dat3d
  USE dimphy, ONLY: klon, zmasq
  USE lmdz_geometry, ONLY: longitude_deg, latitude_deg
  USE phys_state_var_mod, ONLY: pctsrf
  USE control_mod, ONLY: anneeref
  USE init_ssrf_m, ONLY: start_init_subsurf

  INTEGER, PARAMETER :: ns = 256
  CHARACTER(LEN = ns), PARAMETER :: &
          fsst(5) = ['amipbc_sst_1x1.nc   ', 'amip_sst_1x1.nc     ', 'cpl_atm_sst.nc      '&
                  , 'histmth_sst.nc      ', 'sstk.nc             '], &
          fsic(5) = ['amipbc_sic_1x1.nc   ', 'amip_sic_1x1.nc     ', 'cpl_atm_sic.nc      '&
                  , 'histmth_sic.nc      ', 'ci.nc               '], &
          vsst(5) = ['tosbcs    ', 'tos       ', 'SISUTESW  ', 'tsol_oce  ', 'sstk      '], &
          vsic(5) = ['sicbcs    ', 'sic       ', 'SIICECOV  ', 'pourc_sic ', 'ci        '], &
          frugo = 'Rugos.nc  ', falbe = 'Albedo.nc ', frelf = 'Relief.nc ', &
          vrug = 'RUGOS     ', valb = 'ALBEDO    ', vrel = 'RELIEF    ', &
          DegK(11) = ['degK          ', 'degree_K      ', 'degreeK       ', 'deg_K         '&
                  , 'degsK         ', 'degrees_K     ', 'degreesK      ', 'degs_K        '&
                  , 'degree_kelvin ', 'degrees_kelvin', 'K             '], &
          DegC(10) = ['degC          ', 'degree_C      ', 'degreeC       ', 'deg_C         '&
                  , 'degsC         ', 'degrees_C     ', 'degreesC      ', 'degs_C        '&
                  , 'degree_Celsius', 'celsius       '], &
          Perc(2) = ['%             ', 'percent       '], &
          Frac(2) = ['1.0           ', '1             ']

CONTAINS

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

  SUBROUTINE limit_netcdf(masque, phis, extrap)

    !-------------------------------------------------------------------------------
    ! Author : L. Fairhead, 27/01/94
    !-------------------------------------------------------------------------------
    ! Purpose: Boundary conditions files building for new model using climatologies.
    !          Both grids have to be regular.
    !-------------------------------------------------------------------------------
    ! Note: This routine is designed to work for Earth
    !-------------------------------------------------------------------------------
    ! Modification history:
    !  * 23/03/1994: Z. X. Li
    !  *    09/1999: L. Fairhead (netcdf reading in LMDZ.3.3)
    !  *    07/2001: P. Le Van
    !  *    11/2009: L. Guez     (ozone day & night climatos, see etat0_netcdf.F90)
    !  *    12/2009: D. Cugnet   (f77->f90, calendars, files from coupled runs)
    !  *    04/2016: D. Cugnet   (12/14 recs SST/SIC files: cyclic/interannual runs)
    !  *    05/2017: D. Cugnet   (linear time interpolation for BCS files)
    !-------------------------------------------------------------------------------
    USE indice_sol_mod
    USE netcdf, ONLY: nf90_open, nf90_create, nf90_close, &
            nf90_def_dim, nf90_def_var, nf90_put_var, nf90_put_att, &
            nf90_noerr, nf90_nowrite, nf90_global, &
            nf90_clobber, nf90_enddef, nf90_unlimited, nf90_float, &
            nf90_64bit_offset
    USE lmdz_cppkeys_wrapper, ONLY: nf90_format
    USE inter_barxy_m, ONLY: inter_barxy
    USE netcdf95, ONLY: nf95_def_var, nf95_put_att, nf95_put_var
    USE comconst_mod, ONLY: pi
    USE phys_cal_mod, ONLY: calend
    USE lmdz_abort_physic, ONLY: abort_physic
    USE lmdz_iniprint, ONLY: lunout, prt_level
    USE lmdz_comgeom2

  USE lmdz_dimensions, ONLY: iim, jjm, llm, ndm
  USE lmdz_paramet
    IMPLICIT NONE
    !-------------------------------------------------------------------------------
    ! Arguments:


    REAL, DIMENSION(iip1, jjp1), INTENT(INOUT) :: masque ! land mask
    REAL, DIMENSION(iip1, jjp1), INTENT(INOUT) :: phis   ! ground geopotential
    LOGICAL, INTENT(IN) :: extrap ! SST extrapolation flag
    !-------------------------------------------------------------------------------
    ! Local variables:

    !--- INPUT NETCDF FILES AND VARIABLES NAMES ------------------------------------
    CHARACTER(LEN = ns) :: icefile, sstfile, fnam, varname

    !--- OUTPUT VARIABLES FOR NETCDF FILE ------------------------------------------
    REAL :: fi_ice(klon)
    REAL, POINTER :: phy_rug(:, :) => NULL(), phy_ice(:, :) => NULL()
    REAL, POINTER :: phy_sst(:, :) => NULL(), phy_alb(:, :) => NULL()
    REAL, ALLOCATABLE :: phy_bil(:, :), pctsrf_t(:, :, :)
    INTEGER :: nbad

    !--- VARIABLES FOR OUTPUT FILE WRITING -----------------------------------------
    INTEGER :: nid, ndim, ntim, k, dims(2), ix_sic, ix_sst
    INTEGER :: id_tim, id_SST, id_BILS, id_RUG, id_ALB
    INTEGER :: id_FOCE, id_FSIC, id_FTER, id_FLIC, varid_longitude, varid_latitude
    INTEGER :: ndays                   !--- Depending on the output calendar
    CHARACTER(LEN = ns) :: str

    !--- INITIALIZATIONS -----------------------------------------------------------
    CALL inigeom

    !--- MASK, GROUND GEOPOT. & SUBSURFACES COMPUTATION (IN CASE ok_etat0==.FALSE.)
    IF(ALL(masque==-99999.)) THEN
      CALL start_init_orog0(rlonv, rlatu, phis, masque)
      CALL gr_dyn_fi(1, iip1, jjp1, klon, masque, zmasq)          !--- To physical grid
      ALLOCATE(pctsrf(klon, nbsrf))
      CALL start_init_subsurf(.FALSE.)
      !--- TO MATCH EXACTLY WHAT WOULD BE DONE IN etat0phys_netcdf
      WHERE(masque(:, :)<EPSFRA) masque(:, :) = 0.
      WHERE(1. - masque(:, :)<EPSFRA) masque(:, :) = 1.
    END IF

    !--- Beware: anneeref (from gcm.def) is used to determine output time sampling
    ndays = year_len(anneeref)

    !--- RUGOSITY TREATMENT --------------------------------------------------------
    CALL msg(0, ""); CALL msg(0, " *** TRAITEMENT DE LA RUGOSITE ***")
    CALL get_2Dfield(frugo, vrug, 'RUG', ndays, phy_rug, mask = masque(1:iim, :))

    !--- OCEAN TREATMENT -----------------------------------------------------------
    CALL msg(0, ""); CALL msg(0, " *** TRAITEMENT DE LA GLACE OCEANIQUE ***")

    ! Input SIC file selection
    ! Open file only to test if available
    DO ix_sic = 1, SIZE(fsic)
      IF (nf90_open(TRIM(fsic(ix_sic)), nf90_nowrite, nid)==nf90_noerr) THEN
        icefile = fsic(ix_sic); varname = vsic(ix_sic); EXIT
      END IF
    END DO
    IF(ix_sic==SIZE(fsic) + 1) THEN
      WRITE(lunout, *) 'ERROR! No sea-ice input file was found.'
      WRITE(lunout, *) 'One of following files must be available : '
      DO k = 1, SIZE(fsic); WRITE(lunout, *) TRIM(fsic(k));
      END DO
      CALL abort_physic('limit_netcdf', 'No sea-ice file was found', 1)
    END IF
    CALL ncerr(nf90_close(nid), icefile)
    CALL msg(0, 'Fichier choisi pour la glace de mer:' // TRIM(icefile))

    CALL get_2Dfield(icefile, varname, 'SIC', ndays, phy_ice)

    ALLOCATE(pctsrf_t(klon, nbsrf, ndays))
    DO k = 1, ndays
      fi_ice = phy_ice(:, k)
      WHERE(fi_ice>=1.0) fi_ice = 1.0
      WHERE(fi_ice<EPSFRA) fi_ice = 0.0
      pctsrf_t(:, is_ter, k) = pctsrf(:, is_ter)       ! land soil
      pctsrf_t(:, is_lic, k) = pctsrf(:, is_lic)       ! land ice
      SELECT CASE(ix_sic)
      CASE(3)                                   ! SIC=pICE*(1-LIC-TER) (CPL)
        pctsrf_t(:, is_sic, k) = fi_ice(:) * (1. - pctsrf(:, is_lic) - pctsrf(:, is_ter))
      CASE(4)                                   ! SIC=pICE            (HIST)
        pctsrf_t(:, is_sic, k) = fi_ice(:)
      CASE DEFAULT                              ! SIC=pICE-LIC   (AMIP,ERAI)
        pctsrf_t(:, is_sic, k) = fi_ice - pctsrf_t(:, is_lic, k)
      END SELECT
      WHERE(pctsrf_t(:, is_sic, k)<=0) pctsrf_t(:, is_sic, k) = 0.
      WHERE(1.0 - zmasq<EPSFRA)
        pctsrf_t(:, is_sic, k) = 0.0
        pctsrf_t(:, is_oce, k) = 0.0
      ELSEWHERE
        WHERE(pctsrf_t(:, is_sic, k)>=1.0 - zmasq)
          pctsrf_t(:, is_sic, k) = 1.0 - zmasq
          pctsrf_t(:, is_oce, k) = 0.0
        ELSEWHERE
          pctsrf_t(:, is_oce, k) = 1.0 - zmasq - pctsrf_t(:, is_sic, k)
          WHERE(pctsrf_t(:, is_oce, k)<EPSFRA)
            pctsrf_t(:, is_oce, k) = 0.0
            pctsrf_t(:, is_sic, k) = 1.0 - zmasq
          END WHERE
        END WHERE
      END WHERE
      nbad = COUNT(pctsrf_t(:, is_oce, k)<0.0)
      IF(nbad>0) WRITE(lunout, *) 'pb sous maille pour nb points = ', nbad
      nbad = COUNT(ABS(SUM(pctsrf_t(:, :, k), DIM = 2) - 1.0)>EPSFRA)
      IF(nbad>0) WRITE(lunout, *) 'pb sous surface pour nb points = ', nbad
    END DO
    DEALLOCATE(phy_ice)

    !--- SST TREATMENT -------------------------------------------------------------
    CALL msg(0, ""); CALL msg(0, " *** TRAITEMENT DE LA SST ***")

    ! Input SST file selection
    ! Open file only to test if available
    DO ix_sst = 1, SIZE(fsst)
      IF (nf90_open(TRIM(fsst(ix_sst)), nf90_nowrite, nid)==nf90_noerr) THEN
        sstfile = fsst(ix_sst); varname = vsst(ix_sst); EXIT
      END IF
    END DO
    IF(ix_sst==SIZE(fsst) + 1) THEN
      WRITE(lunout, *) 'ERROR! No sst input file was found.'
      WRITE(lunout, *) 'One of following files must be available : '
      DO k = 1, SIZE(fsst); WRITE(lunout, *) TRIM(fsst(k));
      END DO
      CALL abort_physic('limit_netcdf', 'No sst file was found', 1)
    END IF
    CALL ncerr(nf90_close(nid), sstfile)
    CALL msg(0, 'Fichier choisi pour la temperature de mer: ' // TRIM(sstfile))

    CALL get_2Dfield(sstfile, varname, 'SST', ndays, phy_sst, flag = extrap)

    !--- ALBEDO TREATMENT ----------------------------------------------------------
    CALL msg(0, ""); CALL msg(0, " *** TRAITEMENT DE L'ALBEDO ***")
    CALL get_2Dfield(falbe, valb, 'ALB', ndays, phy_alb)

    !--- REFERENCE GROUND HEAT FLUX TREATMENT --------------------------------------
    ALLOCATE(phy_bil(klon, ndays)); phy_bil = 0.0

    !--- OUTPUT FILE WRITING -------------------------------------------------------
    CALL msg(0, ""); CALL msg(0, ' *** Ecriture du fichier limit : debut ***')
    fnam = "limit.nc"

    !--- File creation
    CALL ncerr(nf90_create(fnam, IOR(nf90_clobber, nf90_64bit_offset), nid), fnam)
    CALL ncerr(nf90_put_att(nid, nf90_global, "title", "Fichier conditions aux limites"), fnam)
    str = 'File produced using ce0l executable.'
    str = TRIM(str) // NEW_LINE(' ') // 'Sea Ice Concentration built from'
    SELECT CASE(ix_sic)
    CASE(1); str = TRIM(str) // ' Amip mid-month boundary condition (BCS).'
    CASE(2); str = TRIM(str) // ' Amip monthly mean observations.'
    CASE(3); str = TRIM(str) // ' IPSL coupled model outputs.'
    CASE(4); str = TRIM(str) // ' LMDZ model outputs.'
    CASE(5); str = TRIM(str) // ' ci.nc file.'
    END SELECT
    str = TRIM(str) // NEW_LINE(' ') // 'Sea Surface Temperature built from'
    SELECT CASE(ix_sst)
    CASE(1); str = TRIM(str) // ' Amip mid-month boundary condition (BCS).'
    CASE(2); str = TRIM(str) // ' Amip monthly mean observations.'
    CASE(3); str = TRIM(str) // ' IPSL coupled model outputs.'
    CASE(4); str = TRIM(str) // ' LMDZ model outputs.'
    CASE(5); str = TRIM(str) // ' sstk.nc file.'
    END SELECT
    CALL ncerr(nf90_put_att(nid, nf90_global, "history", TRIM(str)), fnam)

    !--- Dimensions creation
    CALL ncerr(nf90_def_dim(nid, "points_physiques", klon, ndim), fnam)
    CALL ncerr(nf90_def_dim(nid, "time", nf90_unlimited, ntim), fnam)

    dims = [ndim, ntim]

    !--- Variables creation
    CALL ncerr(nf90_def_var(nid, "TEMPS", nf90_format, [ntim], id_tim), fnam)
    CALL ncerr(nf90_def_var(nid, "FOCE", nf90_format, dims, id_FOCE), fnam)
    CALL ncerr(nf90_def_var(nid, "FSIC", nf90_format, dims, id_FSIC), fnam)
    CALL ncerr(nf90_def_var(nid, "FTER", nf90_format, dims, id_FTER), fnam)
    CALL ncerr(nf90_def_var(nid, "FLIC", nf90_format, dims, id_FLIC), fnam)
    CALL ncerr(nf90_def_var(nid, "SST", nf90_format, dims, id_SST), fnam)
    CALL ncerr(nf90_def_var(nid, "BILS", nf90_format, dims, id_BILS), fnam)
    CALL ncerr(nf90_def_var(nid, "ALB", nf90_format, dims, id_ALB), fnam)
    CALL ncerr(nf90_def_var(nid, "RUG", nf90_format, dims, id_RUG), fnam)
    CALL nf95_def_var(nid, "longitude", nf90_float, ndim, varid_longitude)
    CALL nf95_def_var(nid, "latitude", nf90_float, ndim, varid_latitude)

    !--- Attributes creation
    CALL ncerr(nf90_put_att(nid, id_tim, "title", "Jour dans l annee"), fnam)
    CALL ncerr(nf90_put_att(nid, id_tim, "calendar", calend), fnam)
    CALL ncerr(nf90_put_att(nid, id_FOCE, "title", "Fraction ocean"), fnam)
    CALL ncerr(nf90_put_att(nid, id_FSIC, "title", "Fraction glace de mer"), fnam)
    CALL ncerr(nf90_put_att(nid, id_FTER, "title", "Fraction terre"), fnam)
    CALL ncerr(nf90_put_att(nid, id_FLIC, "title", "Fraction land ice"), fnam)
    CALL ncerr(nf90_put_att(nid, id_SST, "title", "Temperature superficielle de la mer"), fnam)
    CALL ncerr(nf90_put_att(nid, id_BILS, "title", "Reference flux de chaleur au sol"), fnam)
    CALL ncerr(nf90_put_att(nid, id_ALB, "title", "Albedo a la surface"), fnam)
    CALL ncerr(nf90_put_att(nid, id_RUG, "title", "Rugosite"), fnam)

    CALL nf95_put_att(nid, varid_longitude, "standard_name", "longitude")
    CALL nf95_put_att(nid, varid_longitude, "units", "degrees_east")

    CALL nf95_put_att(nid, varid_latitude, "standard_name", "latitude")
    CALL nf95_put_att(nid, varid_latitude, "units", "degrees_north")

    CALL ncerr(nf90_enddef(nid), fnam)

    !--- Variables saving
    CALL ncerr(nf90_put_var(nid, id_tim, [(REAL(k), k = 1, ndays)]), fnam)
    CALL ncerr(nf90_put_var(nid, id_FOCE, pctsrf_t(:, is_oce, :), [1, 1], [klon, ndays]), fnam)
    CALL ncerr(nf90_put_var(nid, id_FSIC, pctsrf_t(:, is_sic, :), [1, 1], [klon, ndays]), fnam)
    CALL ncerr(nf90_put_var(nid, id_FTER, pctsrf_t(:, is_ter, :), [1, 1], [klon, ndays]), fnam)
    CALL ncerr(nf90_put_var(nid, id_FLIC, pctsrf_t(:, is_lic, :), [1, 1], [klon, ndays]), fnam)
    CALL ncerr(nf90_put_var(nid, id_SST, phy_sst(:, :), [1, 1], [klon, ndays]), fnam)
    CALL ncerr(nf90_put_var(nid, id_BILS, phy_bil(:, :), [1, 1], [klon, ndays]), fnam)
    CALL ncerr(nf90_put_var(nid, id_ALB, phy_alb(:, :), [1, 1], [klon, ndays]), fnam)
    CALL ncerr(nf90_put_var(nid, id_RUG, phy_rug(:, :), [1, 1], [klon, ndays]), fnam)
    CALL nf95_put_var(nid, varid_longitude, longitude_deg)
    CALL nf95_put_var(nid, varid_latitude, latitude_deg)

    CALL ncerr(nf90_close(nid), fnam)

    CALL msg(0, ""); CALL msg(0, ' *** Ecriture du fichier limit : fin ***')

    DEALLOCATE(pctsrf_t, phy_sst, phy_bil, phy_alb, phy_rug)


    !===============================================================================

  CONTAINS

    !===============================================================================


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

    SUBROUTINE get_2Dfield(fnam, varname, mode, ndays, champo, flag, mask)

      !-----------------------------------------------------------------------------
      ! Comments:
      !   There are two assumptions concerning the NetCDF files, that are satisfied
      !   with files that are conforming NC convention:
      !     1) The last dimension of the variables used is the time record.
      !     2) Dimensional variables have the same names as corresponding dimensions.
      !-----------------------------------------------------------------------------
      USE netcdf, ONLY: nf90_open, nf90_inq_varid, nf90_inquire_variable, &
              nf90_close, nf90_inq_dimid, nf90_inquire_dimension, nf90_get_var, &
              nf90_get_att
      USE lmdz_libmath_pch, ONLY: pchsp_95, pchfe_95
      USE lmdz_arth, ONLY: arth
      USE indice_sol_mod
      USE lmdz_abort_physic, ONLY: abort_physic
      USE lmdz_libmath, ONLY: minmax
      USE lmdz_comgeom2

USE lmdz_dimensions, ONLY: iim, jjm, llm, ndm
  USE lmdz_paramet
      IMPLICIT NONE


      !-----------------------------------------------------------------------------
      ! Arguments:
      CHARACTER(LEN = *), INTENT(IN) :: fnam     ! NetCDF file name
      CHARACTER(LEN = *), INTENT(IN) :: varname  ! NetCDF variable name
      CHARACTER(LEN = *), INTENT(IN) :: mode     ! RUG, SIC, SST or ALB
      INTEGER, INTENT(IN) :: ndays    ! current year number of days
      REAL, POINTER, DIMENSION(:, :) :: champo  ! output field = f(t)
      LOGICAL, OPTIONAL, INTENT(IN) :: flag     ! extrapol. (SST) old ice (SIC)
      REAL, OPTIONAL, DIMENSION(iim, jjp1), INTENT(IN) :: mask
      !------------------------------------------------------------------------------
      ! Local variables:
      !--- NetCDF
      INTEGER :: ncid, varid        ! NetCDF identifiers
      CHARACTER(LEN = ns) :: dnam               ! dimension name
      !--- dimensions
      INTEGER :: dids(4)            ! NetCDF dimensions identifiers
      REAL, ALLOCATABLE :: dlon_ini(:)        ! initial longitudes vector
      REAL, ALLOCATABLE :: dlat_ini(:)        ! initial latitudes  vector
      REAL, POINTER :: dlon(:), dlat(:)   ! reordered lon/lat  vectors
      !--- fields
      INTEGER :: imdep, jmdep, lmdep          ! dimensions of 'champ'
      REAL, ALLOCATABLE :: champ(:, :)         ! wanted field on initial grid
      REAL, ALLOCATABLE :: yder(:), timeyear(:)
      REAL :: champint(iim, jjp1) ! interpolated field
      REAL, ALLOCATABLE :: champtime(:, :, :)
      REAL, ALLOCATABLE :: champan(:, :, :)
      !--- input files
      CHARACTER(LEN = ns) :: fnam_m, fnam_p     ! previous/next files names
      CHARACTER(LEN = ns) :: cal_in             ! calendar
      CHARACTER(LEN = ns) :: units              ! attribute "units" in sic/sst file
      INTEGER :: ndays_in           ! number of days
      REAL :: value              ! mean/max value near equator
      !--- misc
      INTEGER :: i, j, k, l         ! loop counters
      REAL, ALLOCATABLE :: work(:, :)          ! used for extrapolation
      CHARACTER(LEN = ns) :: title, mess        ! for messages
      LOGICAL :: is_bcs             ! flag for BCS data
      LOGICAL :: extrp              ! flag for extrapolation
      LOGICAL :: ll
      REAL :: chmin, chmax, timeday, al
      INTEGER ierr, idx
      INTEGER n_extrap ! number of extrapolated points
      LOGICAL skip

      !------------------------------------------------------------------------------
      !---Variables depending on keyword 'mode' -------------------------------------
      NULLIFY(champo)

      SELECT CASE(mode)
      CASE('RUG'); title = 'Rugosite'
      CASE('SIC'); title = 'Sea-ice'
      CASE('SST'); title = 'SST'
      CASE('ALB'); title = 'Albedo'
      END SELECT
      extrp = .FALSE.; IF(PRESENT(flag).AND.mode=='SST') extrp = flag
      is_bcs = (mode=='SIC'.AND.ix_sic==1).OR.(mode=='SST'.AND.ix_sst==1)
      idx = INDEX(fnam, '.nc') - 1

      !--- GETTING SOME DIMENSIONAL VARIABLES FROM FILE -----------------------------
      CALL msg(5, ' Now reading file : ' // TRIM(fnam))
      CALL ncerr(nf90_open(fnam, nf90_nowrite, ncid), fnam)
      CALL ncerr(nf90_inq_varid(ncid, trim(varname), varid), fnam)
      CALL ncerr(nf90_inquire_variable(ncid, varid, dimids = dids), fnam)

      !--- Longitude
      CALL ncerr(nf90_inquire_dimension(ncid, dids(1), name = dnam, len = imdep), fnam)
      ALLOCATE(dlon_ini(imdep), dlon(imdep))
      CALL ncerr(nf90_inq_varid(ncid, dnam, varid), fnam)
      CALL ncerr(nf90_get_var(ncid, varid, dlon_ini), fnam)
      CALL msg(5, 'variable ' // TRIM(dnam) // ' dimension ', imdep)

      !--- Latitude
      CALL ncerr(nf90_inquire_dimension(ncid, dids(2), name = dnam, len = jmdep), fnam)
      ALLOCATE(dlat_ini(jmdep), dlat(jmdep))
      CALL ncerr(nf90_inq_varid(ncid, dnam, varid), fnam)
      CALL ncerr(nf90_get_var(ncid, varid, dlat_ini), fnam)
      CALL msg(5, 'variable ' // TRIM(dnam) // ' dimension ', jmdep)

      !--- Time (variable is not needed - it is rebuilt - but calendar is)
      CALL ncerr(nf90_inquire_dimension(ncid, dids(3), name = dnam, len = lmdep), fnam)
      ALLOCATE(timeyear(lmdep + 2))
      CALL ncerr(nf90_inq_varid(ncid, dnam, varid), fnam)
      cal_in = ' '
      IF(nf90_get_att(ncid, varid, 'calendar', cal_in)/=nf90_noerr) THEN
        SELECT CASE(mode)
        CASE('RUG', 'ALB'); cal_in = '360_day'
        CASE('SIC', 'SST'); cal_in = 'gregorian'
        END SELECT
        CALL msg(0, 'WARNING: missing "calendar" attribute for "time" in '&
                // TRIM(fnam) // '. Choosing default value.')
      END IF
      CALL strclean(cal_in)                     !--- REMOVE (WEIRD) NULL CHARACTERS
      CALL msg(0, 'var, calendar, dim: ' // TRIM(dnam) // ' ' // TRIM(cal_in), lmdep)

      !--- Determining input file number of days, depending on calendar
      ndays_in = year_len(anneeref, cal_in)

      !--- Rebuilding input time vector (field from input file might be unreliable)
      IF(lmdep==12) THEN
        timeyear = mid_month(anneeref, cal_in)
        CALL msg(0, 'Monthly input file(s) for ' // TRIM(title) // '.')
      ELSE IF(lmdep==ndays_in) THEN
        timeyear = [(REAL(k) - 0.5, k = 0, ndays_in + 1)]
        CALL msg(0, 'Daily input file (no time interpolation).')
      ELSE
        WRITE(mess, '(a,i3,a,i3,a)')'Mismatching input file: found', lmdep, &
                ' records, 12/', ndays_in, ' (monthly/daily needed).'
        CALL abort_physic('mid_month', TRIM(mess), 1)
      END IF

      !--- GETTING THE FIELD AND INTERPOLATING IT ----------------------------------
      ALLOCATE(champ(imdep, jmdep), champtime(iim, jjp1, lmdep + 2))
      IF(extrp) ALLOCATE(work(imdep, jmdep))
      CALL msg(5, '')
      CALL msg(5, 'READ AND INTERPOLATE HORIZONTALLY ', lmdep, ' FIELDS.')
      CALL ncerr(nf90_inq_varid(ncid, varname, varid), fnam)
      DO l = 1, lmdep
        CALL ncerr(nf90_get_var(ncid, varid, champ, [1, 1, l], [imdep, jmdep, 1]), fnam)
        CALL conf_dat2d(title, dlon_ini, dlat_ini, dlon, dlat, champ, .TRUE.)

        !--- FOR SIC/SST FIELDS ONLY
        IF(l==1.AND.is_in(mode, ['SIC', 'SST'])) THEN

          !--- DETERMINE THE UNIT: READ FROM FILE OR ASSUMED USING FIELD VALUES
          ierr = nf90_get_att(ncid, varid, 'units', units)
          IF(ierr==nf90_noerr) THEN !--- ATTRIBUTE "units" FOUND IN THE FILE
            CALL strclean(units)
            IF(mode=='SIC'.AND.is_in(units, Perc)) units = "%"
            IF(mode=='SIC'.AND.is_in(units, Frac)) units = "1"
            IF(mode=='SST'.AND.is_in(units, DegC)) units = "C"
            IF(mode=='SST'.AND.is_in(units, DegK)) units = "K"
          ELSE                      !--- CHECK THE FIELD VALUES
            IF(mode=='SIC') value = MAXVAL(champ(:, :))
            IF(mode=='SST') value = SUM(champ(:, jmdep / 2), DIM = 1) / REAL(imdep)
            IF(mode=='SIC') THEN; units = "1"; IF(value>= 10.) units = "%";
            END IF
            IF(mode=='SST') THEN; units = "C"; IF(value>=100.) units = "K";
            END IF
          END IF
          CALL msg(0, 'INPUT FILE ' // TRIM(title) // ' UNIT IS: "' // TRIM(units) // '".')
          IF(ierr/=nf90_noerr) CALL msg(0, 'WARNING ! UNIT TO BE CHECKED ! '      &
                  // 'No "units" attribute, so only based on the fields values.')

          !--- CHECK VALUES ARE IN THE EXPECTED RANGE
          SELECT CASE(units)
          CASE('%'); ll = ANY(champ>100.0 + EPSFRA); str = 'percentages > 100.'
          CASE('1'); ll = ANY(champ>  1.0 + EPSFRA); str = 'fractions > 1.'
          CASE('C'); ll = ANY(champ<-100.).OR.ANY(champ> 60.); str = '<-100 or >60 DegC'
          CASE('K'); ll = ANY(champ< 180.).OR.ANY(champ>330.); str = '<180 or >330 DegK'
          CASE DEFAULT; CALL abort_physic(mode, 'Unrecognized ' // TRIM(title)   &
                  // ' unit: ' // TRIM(units), 1)
          END SELECT

          !--- DROPPED FOR BCS DATA (FRACTIONS CAN BE HIGHER THAN 1)
          IF(ll.AND.ix_sic/=1.AND.mode=='SIC') &
                  CALL abort_physic(mode, 'unrealistic ' // TRIM(mode) // ' found: ' // TRIM(str), 1)

        END IF

        IF(extrp) CALL extrapol(champ, imdep, jmdep, 999999., .TRUE., .TRUE., 2, work)
        IF(l==1) THEN
          CALL msg(5, "--------------------------------------------------------")
          CALL msg(5, "$$$ Barycentric interpolation for " // TRIM(title) // " $$$")
          CALL msg(5, "--------------------------------------------------------")
        END IF
        IF(mode=='RUG') champ = LOG(champ)
        CALL inter_barxy(dlon, dlat(:jmdep - 1), champ, rlonu(:iim), rlatv, champint)
        IF(mode=='RUG') THEN
          champint = EXP(champint)
          WHERE(NINT(mask)/=1) champint = 0.001
        END IF
        champtime(:, :, l + 1) = champint
      END DO
      CALL ncerr(nf90_close(ncid), fnam)

      !--- FIRST RECORD: LAST ONE OF PREVIOUS YEAR (CURRENT YEAR IF UNAVAILABLE)
      fnam_m = fnam(1:idx) // '_m.nc'
      IF(nf90_open(fnam_m, nf90_nowrite, ncid)==nf90_noerr) THEN
        CALL msg(0, 'Reading previous year file ("' // TRIM(fnam_m) // '") last record for ' // TRIM(title))
        CALL ncerr(nf90_inq_varid(ncid, varname, varid), fnam_m)
        CALL ncerr(nf90_inquire_variable(ncid, varid, dimids = dids), fnam_m)
        CALL ncerr(nf90_inquire_dimension(ncid, dids(3), len = l), fnam_m)
        CALL ncerr(nf90_get_var(ncid, varid, champ, [1, 1, l], [imdep, jmdep, 1]), fnam_m)
        CALL ncerr(nf90_close(ncid), fnam_m)
        CALL conf_dat2d(title, dlon_ini, dlat_ini, dlon, dlat, champ, .TRUE.)
        IF(extrp) CALL extrapol(champ, imdep, jmdep, 999999., .TRUE., .TRUE., 2, work)
        IF(mode=='RUG') champ = LOG(champ)
        CALL inter_barxy(dlon, dlat(:jmdep - 1), champ, rlonu(:iim), rlatv, champint)
        IF(mode=='RUG') THEN
          champint = EXP(champint)
          WHERE(NINT(mask)/=1) champint = 0.001
        END IF
        champtime(:, :, 1) = champint
      ELSE
        CALL msg(0, 'Using current year file ("' // TRIM(fnam) // '") last record for ' // TRIM(title))
        champtime(:, :, 1) = champtime(:, :, lmdep + 1)
      END IF

      !--- LAST RECORD: FIRST ONE OF NEXT YEAR (CURRENT YEAR IF UNAVAILABLE)
      fnam_p = fnam(1:idx) // '_p.nc'
      IF(nf90_open(fnam_p, nf90_nowrite, ncid)==nf90_noerr) THEN
        CALL msg(0, 'Reading next year file ("' // TRIM(fnam_p) // '") first record for ' // TRIM(title))
        CALL ncerr(nf90_inq_varid(ncid, varname, varid), fnam_p)
        CALL ncerr(nf90_get_var(ncid, varid, champ, [1, 1, 1], [imdep, jmdep, 1]), fnam_p)
        CALL ncerr(nf90_close(ncid), fnam_p)
        CALL conf_dat2d(title, dlon_ini, dlat_ini, dlon, dlat, champ, .TRUE.)
        IF(extrp) CALL extrapol(champ, imdep, jmdep, 999999., .TRUE., .TRUE., 2, work)
        IF(mode=='RUG') champ = LOG(champ)
        CALL inter_barxy(dlon, dlat(:jmdep - 1), champ, rlonu(:iim), rlatv, champint)
        IF(mode=='RUG') THEN
          champint = EXP(champint)
          WHERE(NINT(mask)/=1) champint = 0.001
        END IF
        champtime(:, :, lmdep + 2) = champint
      ELSE
        CALL msg(0, 'Using current year file ("' // TRIM(fnam) // '") first record for ' // TRIM(title))
        champtime(:, :, lmdep + 2) = champtime(:, :, 2)
      END IF
      DEALLOCATE(dlon_ini, dlat_ini, dlon, dlat, champ)
      IF(extrp) DEALLOCATE(work)

      !--- TIME INTERPOLATION ------------------------------------------------------
      IF(prt_level>0) THEN
        IF(ndays/=ndays_in) THEN
          WRITE(lunout, *)'DIFFERENT YEAR LENGTHS:'
          WRITE(lunout, *)' In the  input file: ', ndays_in
          WRITE(lunout, *)' In the output file: ', ndays
        END IF
        IF(lmdep==ndays_in) THEN
          WRITE(lunout, *)'NO TIME INTERPOLATION.'
          WRITE(lunout, *)' Daily input file.'
        ELSE
          IF(is_bcs) WRITE(lunout, *)'LINEAR TIME INTERPOLATION.'
          IF(.NOT.is_bcs) WRITE(lunout, *)'SPLINES TIME INTERPOLATION.'
          WRITE(lunout, *)' Input time vector: ', timeyear
          WRITE(lunout, *)' Output time vector: from 0.5 to ', ndays - 0.5
        END IF
      END IF
      ALLOCATE(champan(iip1, jjp1, ndays))

      IF(lmdep==ndays_in) THEN  !--- DAILY DATA: NO     TIME INTERPOLATION
        DO l = 1, lmdep
          champan(1:iim, :, l) = champtime(:, :, l + 1)
        END DO
      ELSE IF(is_bcs) THEN      !--- BCS   DATA: LINEAR TIME INTERPOLATION
        l = 1
        DO k = 1, ndays
          timeday = (REAL(k) - 0.5) * REAL(ndays_in) / ndays
          IF(timeyear(l + 1)<timeday) l = l + 1
          al = (timeday - timeyear(l)) / (timeyear(l + 1) - timeyear(l))
          champan(1:iim, :, k) = champtime(1:iim, :, l) + al * (champtime(1:iim, :, l + 1) - champtime(1:iim, :, l))
        END DO
      ELSE                      !--- AVE   DATA: SPLINE TIME INTERPOLATION
        skip = .FALSE.
        n_extrap = 0
        ALLOCATE(yder(lmdep + 2))
        DO j = 1, jjp1
          DO i = 1, iim
            yder = pchsp_95(timeyear, champtime(i, j, :), ibeg = 2, iend = 2, &
                    vc_beg = 0., vc_end = 0.)
            CALL pchfe_95(timeyear, champtime(i, j, :), yder, skip, &
                    arth(0.5, real(ndays_in) / ndays, ndays), champan(i, j, :), ierr)
            IF (ierr < 0) CALL abort_physic("get_2Dfield", "", 1)
            n_extrap = n_extrap + ierr
          END DO
        END DO
        IF(n_extrap /= 0) WRITE(lunout, *) "get_2Dfield pchfe_95: n_extrap = ", n_extrap
        DEALLOCATE(yder)
      END IF
      champan(iip1, :, :) = champan(1, :, :)
      DEALLOCATE(champtime, timeyear)

      !--- Checking the result
      DO j = 1, jjp1
        CALL minmax(iip1, champan(1, j, 10), chmin, chmax)
        IF (prt_level>5) WRITE(lunout, *)' ', TRIM(title), ' at time 10 ', chmin, chmax, j
      END DO

      !--- SPECIAL FILTER FOR SST: SST>271.38 --------------------------------------
      IF(mode=='SST') THEN
        SELECT CASE(units)
        CASE("K"); CALL msg(0, 'SST field is already in kelvins.')
        CASE("C"); CALL msg(0, 'SST field converted from celcius degrees to kelvins.')
        champan(:, :, :) = champan(:, :, :) + 273.15
        END SELECT
        CALL msg(0, 'Filtering SST: Sea Surface Temperature >= 271.38')
        WHERE(champan<271.38) champan = 271.38
      END IF

      !--- SPECIAL FILTER FOR SIC: 0.0<SIC<1.0 -------------------------------------
      IF(mode=='SIC') THEN
        SELECT CASE(units)
        CASE("1"); CALL msg(0, 'SIC field already in fraction of 1')
        CASE("%"); CALL msg(0, 'SIC field converted from percentage to fraction of 1.')
        champan(:, :, :) = champan(:, :, :) / 100.
        END SELECT
        CALL msg(0, 'Filtering SIC: 0.0 <= Sea-ice <=1.0')
        WHERE(champan>1.0) champan = 1.0
        WHERE(champan<0.0) champan = 0.0
      END IF

      !--- DYNAMICAL TO PHYSICAL GRID ----------------------------------------------
      ALLOCATE(champo(klon, ndays))
      DO k = 1, ndays
        CALL gr_dyn_fi(1, iip1, jjp1, klon, champan(1, 1, k), champo(:, k))
      END DO
      DEALLOCATE(champan)

    END SUBROUTINE get_2Dfield

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


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

    SUBROUTINE start_init_orog0(lon_in, lat_in, phis, masque)
      USE grid_noro_m, ONLY: grid_noro0


      IMPLICIT NONE
      !===============================================================================
      ! Purpose:  Compute "phis" just like it would be in start_init_orog.
      !===============================================================================
      ! Arguments:
      REAL, INTENT(IN) :: lon_in(:), lat_in(:)   ! dim (iml) (jml)
      REAL, INTENT(INOUT) :: phis(:, :), masque(:, :) ! dim (iml,jml)
      !-------------------------------------------------------------------------------
      ! Local variables:
      CHARACTER(LEN = ns) :: modname = "start_init_orog0"
      INTEGER :: fid, llm_tmp, ttm_tmp, iml, jml, iml_rel, jml_rel, itau(1)
      REAL :: lev(1), date, dt, deg2rad
      REAL, ALLOCATABLE :: lon_rad(:), lon_ini(:), lon_rel(:, :), relief_hi(:, :)
      REAL, ALLOCATABLE :: lat_rad(:), lat_ini(:), lat_rel(:, :)
      !-------------------------------------------------------------------------------
      iml = assert_eq(SIZE(lon_in), SIZE(phis, 1), SIZE(masque, 1), TRIM(modname) // " iml")
      jml = assert_eq(SIZE(lat_in), SIZE(phis, 2), SIZE(masque, 2), TRIM(modname) // " jml")
      IF(iml/=iip1) CALL abort_gcm(TRIM(modname), 'iml/=iip1', 1)
      IF(jml/=jjp1) CALL abort_gcm(TRIM(modname), 'jml/=jjp1', 1)
      pi = 2.0 * ASIN(1.0); deg2rad = pi / 180.0
      IF(ANY(phis/=-99999.)) RETURN                  !--- phis ALREADY KNOWN

      !--- HIGH RESOLUTION OROGRAPHY
      CALL flininfo(frelf, iml_rel, jml_rel, llm_tmp, ttm_tmp, fid)

      ALLOCATE(lat_rel(iml_rel, jml_rel), lon_rel(iml_rel, jml_rel))
      CALL flinopen(frelf, .FALSE., iml_rel, jml_rel, llm_tmp, lon_rel, lat_rel, &
              lev, ttm_tmp, itau, date, dt, fid)
      ALLOCATE(relief_hi(iml_rel, jml_rel))
      CALL flinget(fid, vrel, iml_rel, jml_rel, llm_tmp, ttm_tmp, 1, 1, relief_hi)
      CALL flinclo(fid)

      !--- IF ANGLES ARE IN DEGREES, THEY ARE CONVERTED INTO RADIANS
      ALLOCATE(lon_ini(iml_rel), lat_ini(jml_rel))
      lon_ini(:) = lon_rel(:, 1); IF(MAXVAL(lon_rel)>pi) lon_ini = lon_ini * deg2rad
      lat_ini(:) = lat_rel(1, :); IF(MAXVAL(lat_rel)>pi) lat_ini = lat_ini * deg2rad

      !--- FIELDS ARE PROCESSED TO BE ON STANDARD ANGULAR DOMAINS
      ALLOCATE(lon_rad(iml_rel), lat_rad(jml_rel))
      CALL conf_dat2d(vrel, lon_ini, lat_ini, lon_rad, lat_rad, relief_hi, .FALSE.)
      DEALLOCATE(lon_ini, lat_ini)

      !--- COMPUTING SURFACE GEOPOTENTIAL USING ROUTINE grid_noro0
      WRITE(lunout, *)
      WRITE(lunout, *)'*** Compute surface geopotential ***'

      !--- CALL OROGRAPHY MODULE (REDUCED VERSION) TO COMPUTE FIELDS
      CALL grid_noro0(lon_rad, lat_rad, relief_hi, lon_in, lat_in, phis, masque)
      phis = phis * 9.81
      phis(iml, :) = phis(1, :)
      DEALLOCATE(relief_hi, lon_rad, lat_rad)

    END SUBROUTINE start_init_orog0

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


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

    SUBROUTINE msg(lev, str1, i, str2)

      !-------------------------------------------------------------------------------
      ! Arguments:
      INTEGER, INTENT(IN) :: lev
      CHARACTER(LEN = *), INTENT(IN) :: str1
      INTEGER, OPTIONAL, INTENT(IN) :: i
      CHARACTER(LEN = *), OPTIONAL, INTENT(IN) :: str2
      !-------------------------------------------------------------------------------
      IF(prt_level>=lev) THEN
        IF(PRESENT(str2)) THEN
          WRITE(lunout, *) TRIM(str1), i, TRIM(str2)
        ELSE IF(PRESENT(i)) THEN
          WRITE(lunout, *) TRIM(str1), i
        ELSE
          WRITE(lunout, *) TRIM(str1)
        END IF
      END IF

    END SUBROUTINE msg

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


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

    SUBROUTINE ncerr(ncres, fnam)

      !-------------------------------------------------------------------------------
      ! Purpose: NetCDF errors handling.
      !-------------------------------------------------------------------------------
      USE netcdf, ONLY: nf90_noerr, nf90_strerror
      USE lmdz_abort_physic, ONLY: abort_physic
      IMPLICIT NONE
      !-------------------------------------------------------------------------------
      ! Arguments:
      INTEGER, INTENT(IN) :: ncres
      CHARACTER(LEN = *), INTENT(IN) :: fnam
      !-------------------------------------------------------------------------------
      IF(ncres/=nf90_noerr) THEN
        WRITE(lunout, *)'Problem with file ' // TRIM(fnam) // ' in routine limit_netcdf.'
        CALL abort_physic('limit_netcdf', nf90_strerror(ncres), 1)
      END IF

    END SUBROUTINE ncerr

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


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

    SUBROUTINE strclean(s)

      !-------------------------------------------------------------------------------
      IMPLICIT NONE
      !-------------------------------------------------------------------------------
      ! Purpose: Remove tail null characters from the input string.
      !-------------------------------------------------------------------------------
      ! Parameters:
      CHARACTER(LEN = *), INTENT(INOUT) :: s
      !-------------------------------------------------------------------------------
      ! Local variable:
      INTEGER :: k
      !-------------------------------------------------------------------------------
      k = LEN_TRIM(s); DO WHILE(ICHAR(s(k:k))==0); s(k:k) = ' '; k = LEN_TRIM(s);
      END DO

    END SUBROUTINE strclean

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


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

    FUNCTION is_in(s1, s2) RESULT(res)

      !-------------------------------------------------------------------------------
      IMPLICIT NONE
      !-------------------------------------------------------------------------------
      ! Purpose: Check wether s1 is present in the s2(:) list (case insensitive).
      !-------------------------------------------------------------------------------
      ! Arguments:
      CHARACTER(LEN = *), INTENT(IN) :: s1, s2(:)
      LOGICAL :: res
      !-------------------------------------------------------------------------------
      res = .FALSE.; DO k = 1, SIZE(s2); res = res.OR.strLow(s1)==strLow(s2(k));
      END DO

    END FUNCTION is_in

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


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

    ELEMENTAL FUNCTION strLow(s) RESULT(res)

      !-------------------------------------------------------------------------------
      IMPLICIT NONE
      !-------------------------------------------------------------------------------
      ! Purpose: Lower case conversion.
      !-------------------------------------------------------------------------------
      ! Arguments:
      CHARACTER(LEN = *), INTENT(IN) :: s
      CHARACTER(LEN = ns) :: res
      !-------------------------------------------------------------------------------
      ! Local variable:
      INTEGER :: k, ix
      !-------------------------------------------------------------------------------
      res = s
      DO k = 1, LEN(s); ix = IACHAR(s(k:k))
      IF(64<ix.AND.ix<91) res(k:k) = ACHAR(ix + 32)
      END DO

    END FUNCTION strLow

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

  END SUBROUTINE limit_netcdf

END MODULE limit

!*******************************************************************************