data_override.inc

!***********************************************************************
!*                   GNU Lesser General Public License
!*
!* This file is part of the GFDL Flexible Modeling System (FMS).
!*
!* FMS is free software: you can redistribute it and/or modify it under
!* the terms of the GNU Lesser General Public License as published by
!* the Free Software Foundation, either version 3 of the License, or (at
!* your option) any later version.
!*
!* FMS is distributed in the hope that it will be useful, but WITHOUT
!* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
!* FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
!* for more details.
!*
!* You should have received a copy of the GNU Lesser General Public
!* License along with FMS.  If not, see <http://www.gnu.org/licenses/>.
!***********************************************************************
 
! This file contains the body of the data_override_r4 and data_override_r8
! modules. These modules are not intended to be used directly - they should be
! used through the data_override_mod API. See data_override.F90 for details.
 
use platform_mod, only: r4_kind, r8_kind, fms_path_len, fms_file_len
use yaml_parser_mod
use constants_mod, only: deg_to_rad
use mpp_mod, only : mpp_error, fatal, warning, note, stdout, stdlog, mpp_max
use mpp_mod, only : input_nml_file
use horiz_interp_mod, only : horiz_interp_init, horiz_interp_new, horiz_interp_type, &
                             horiz_interp_read_weights
use time_interp_external2_mod, only: time_interp_external_init, &
                                     time_interp_external, &
                                     time_interp_external_bridge, get_time_axis, &
                                     init_external_field, &
                                     get_external_field_size, &
                                     set_override_region, &
                                     reset_src_data_region, &
                                     no_region, inside_region, outside_region, &
                                     get_external_fileobj
use fms_mod, only: write_version_number, lowercase, check_nml_error
use axis_utils2_mod,  only : nearest_index, axis_edges
use mpp_domains_mod, only : domain2d, mpp_get_compute_domain, null_domain2d,operator(.NE.),operator(.EQ.)
use mpp_domains_mod, only : mpp_get_global_domain, mpp_get_data_domain
use mpp_domains_mod, only : domainug, mpp_pass_sg_to_ug, mpp_get_ug_sg_domain, null_domainug
use time_manager_mod, only: time_type, OPERATOR(>), OPERATOR(<)
use fms2_io_mod,     only : fmsnetcdffile_t, open_file, close_file, &
                            read_data, fms2_io_init, variable_exists, &
                            get_mosaic_tile_file, file_exists, get_instance_filename
use get_grid_version_mod, only: get_grid_version_1, get_grid_version_2
use fms_string_utils_mod, only: string
 
implicit none
private
 
! Include variable "version" to be written to log file.
#include<file_version.h>
 
!> Private type for holding field and grid information from a data table
!> @ingroup data_override_mod
type data_type
   character(len=3)   :: gridname
   character(len=128) :: fieldname_code  !< fieldname used in user's code (model)
   character(len=128) :: fieldname_file  !< fieldname used in the netcdf data file
   character(len=FMS_PATH_LEN) :: file_name       !< name of netCDF data file
   character(len=128) :: interpol_method !< interpolation method (default "bilinear")
   logical            :: ext_weights
   character(len=128) :: ext_weights_file_name
   character(len=128) :: ext_weights_source
   real(FMS_DATA_OVERRIDE_KIND_)        :: factor          !< For unit conversion, default=1, see OVERVIEW above
   real(FMS_DATA_OVERRIDE_KIND_)        :: lon_start, lon_end, lat_start, lat_end
   integer            :: region_type
   logical            :: multifile = .false.
   character(len=FMS_PATH_LEN) :: prev_file_name   !< name of netCDF data file for previous segment
   character(len=FMS_PATH_LEN) :: next_file_name   !< name of netCDF data file for next segment
   type(time_type), dimension(:), allocatable :: time_records
   type(time_type), dimension(:), allocatable :: time_prev_records
   type(time_type), dimension(:), allocatable :: time_next_records
end type data_type
 
!> Private type for holding various data fields for performing data overrides
!> @ingroup data_override_mod
type override_type
   character(len=3)                 :: gridname
   character(len=128)               :: fieldname
   integer                          :: t_index            !< index for time interp
   integer                          :: pt_index           !< previous index for time interp
   integer                          :: nt_index           !< next index for time interp
   type(horiz_interp_type), allocatable :: horz_interp(:) !< index for horizontal spatial interp
   integer                          :: dims(4)            !< dimensions(x,y,z,t) of the field in filename
   integer                          :: comp_domain(4)     !< istart,iend,jstart,jend for compute domain
   integer                          :: numthreads
   real(FMS_DATA_OVERRIDE_KIND_), allocatable :: lon_in(:)
   real(FMS_DATA_OVERRIDE_KIND_), allocatable :: lat_in(:)
   logical, allocatable             :: need_compute(:)
   integer                          :: numwindows
   integer                          :: window_size(2)
   integer                          :: is_src, ie_src, js_src, je_src
end type override_type
 
!> Private type for holding horiz_interp_type for a weight file
!! This is needed so that if variables use the same weight file,
!! then we won't have to read the weight file again
!> @ingroup data_override_mod
type fmsexternalweights_type
  character(len=:), allocatable :: weight_filename !< Name of the weight file
  type(horiz_interp_type)       :: horiz_interp    !< Horiz interp type read in from the weight file
end type fmsexternalweights_type
 
integer, parameter :: lkind = fms_data_override_kind_
integer, parameter :: max_table=100, max_array=100
 
integer            :: table_size !< actual size of data table
integer            :: nweight_files !< Number of weight files that have been used
type(fmsExternalWeights_type), allocatable, target :: external_weights(:) !< External weights types
logical            :: module_is_initialized = .false.
 
type(domain2D) :: ocn_domain,atm_domain,lnd_domain, ice_domain
type(domainUG) :: lnd_domainUG
 
real(FMS_DATA_OVERRIDE_KIND_), dimension(:,:), target, allocatable :: lon_local_ocn, lat_local_ocn
real(FMS_DATA_OVERRIDE_KIND_), dimension(:,:), target, allocatable :: lon_local_atm, lat_local_atm
real(FMS_DATA_OVERRIDE_KIND_), dimension(:,:), target, allocatable :: lon_local_ice, lat_local_ice
real(FMS_DATA_OVERRIDE_KIND_), dimension(:,:), target, allocatable :: lon_local_lnd, lat_local_lnd
real(FMS_DATA_OVERRIDE_KIND_) :: min_glo_lon_ocn, max_glo_lon_ocn
real(FMS_DATA_OVERRIDE_KIND_) :: min_glo_lon_atm, max_glo_lon_atm
real(FMS_DATA_OVERRIDE_KIND_) :: min_glo_lon_lnd, max_glo_lon_lnd
real(FMS_DATA_OVERRIDE_KIND_) :: min_glo_lon_ice, max_glo_lon_ice
integer :: num_fields = 0 !< number of fields in override_array already processed
 
type(data_type), dimension(:), allocatable :: data_table !< user-provided data table
 
type(data_type)                            :: default_table
type(override_type), dimension(max_array)  :: override_array !< to store processed fields
type(override_type)                        :: default_array
logical                                    :: debug_data_override
logical                                    :: grid_center_bug = .false.
logical                                    :: reproduce_null_char_bug = .false. !> Flag indicating
                                              !! to reproduce the mpp_io bug where lat/lon_bnd were
                                              !! not read correctly if null characters are present in
                                              !! the netcdf file
logical                                    :: use_center_grid_points=.false. !< Flag indicating
                                              !! whether or not to use the centroid values of the
                                              !! supergrid from the grid file as opposed to calculating it
                                              !! by taking the average of the four corner points.
                                              !! This is only relevant to OCN and ICE grids.
logical                                    :: use_data_table_yaml = .false.
 
namelist /data_override_nml/ debug_data_override, grid_center_bug, reproduce_null_char_bug, use_data_table_yaml, &
                             use_center_grid_points
 
public :: data_override_init_impl_, data_override_unset_atm_, data_override_unset_ocn_, &
        & data_override_unset_lnd_, data_override_unset_ice_, data_override_0d_, &
        & data_override_2d_, data_override_3d_, data_override_ug_1d_, &
        & data_override_ug_2d_
 
contains
 
!> @brief Assign default values for default_table, get domain of component models,
!! get global grids of component models.
!! Users should call data_override_init before calling data_override
!!
!! This subroutine should be called by data_override_init.
!!
!! Data_table is initialized here with default values. Users should provide "real" values
!! that will override the default values. Real values can be specified in either data_table
!! or data_table.yaml. Each line of data_table contains one data_entry. Items of data_entry
!! are comma-separated.
subroutine data_override_init_impl_(Atm_domain_in, Ocean_domain_in, Ice_domain_in, Land_domain_in, Land_domainUG_in)
  type (domain2d), intent(in), optional :: Atm_domain_in    !> Atmosphere domain
  type (domain2d), intent(in), optional :: Ocean_domain_in  !> Ocean domain
  type (domain2d), intent(in), optional :: Ice_domain_in    !> Ice domain
  type (domain2d), intent(in), optional :: Land_domain_in   !> Land domain
  type(domainUG) , intent(in), optional :: Land_domainUG_in !> Land domain, unstructured grid
 
  character(len=18), parameter    :: grid_file = 'INPUT/grid_spec.nc'
  integer               :: is,ie,js,je,use_get_grid_version
  integer               :: i, iunit, io_status, ierr
  logical               :: atm_on, ocn_on, lnd_on, ice_on, lndUG_on
  logical               :: file_open
  type(FmsNetcdfFile_t) :: fileobj
 
  debug_data_override = .false.
 
  read (input_nml_file, data_override_nml, iostat=io_status)
  ierr = check_nml_error(io_status, 'data_override_nml')
  iunit = stdlog()
  write(iunit, data_override_nml)
 
! grid_center_bug is no longer supported.
if (grid_center_bug) then
  call mpp_error(fatal, "data_override_init: You have overridden the default value of " // &
     "grid_center_bug and set it to .true. in data_override_nml.  This was a temporary workaround " // &
     "that is no longer supported. Please remove this namelist variable.")
endif
 
if (use_data_table_yaml) then
   call mpp_error(note, "You are using YAML.")
else
   call mpp_error(note, "You are using the legacy table.")
end if
 
  atm_on = PRESENT(atm_domain_in)
  ocn_on = PRESENT(ocean_domain_in)
  lnd_on = PRESENT(land_domain_in)
  ice_on = PRESENT(ice_domain_in)
  lndug_on = PRESENT(land_domainug_in)
  if(.not. module_is_initialized) then
    atm_domain = null_domain2d
    ocn_domain = null_domain2d
    lnd_domain = null_domain2d
    ice_domain = null_domain2d
    lnd_domainug = null_domainug
  end if
  if (atm_on) atm_domain = atm_domain_in
  if (ocn_on) ocn_domain = ocean_domain_in
  if (lnd_on) lnd_domain = land_domain_in
  if (ice_on) ice_domain = ice_domain_in
  if (lndug_on) lnd_domainug = land_domainug_in
 
  if(.not. module_is_initialized) then
    call horiz_interp_init
    call write_version_number("DATA_OVERRIDE_MOD", version)
 
!  Initialize user-provided data table
    default_table%gridname = 'non'
    default_table%fieldname_code = 'none'
    default_table%fieldname_file = 'none'
    default_table%file_name = 'none'
    default_table%factor = 1._lkind
    default_table%interpol_method = 'bilinear'
    default_table%multifile = .false.
    default_table%prev_file_name = ''
    default_table%next_file_name = ''
 
#ifdef use_yaml
    if (use_data_table_yaml) then
       if (file_exists("data_table")) &
         call mpp_error(fatal, "You cannot have the legacy data_table if use_data_table_yaml=.true.")
       call read_table_yaml(data_table)
       allocate(external_weights(table_size))
       nweight_files = 0
    else
       if (file_exists("data_table.yaml"))&
         call mpp_error(fatal, "You cannot have the yaml data_table if use_data_table_yaml=.false.")
       allocate(data_table(max_table))
       do i = 1, max_table
          data_table(i) = default_table
       enddo
       call read_table(data_table)
    end if
#else
    if (file_exists("data_table.yaml"))&
         call mpp_error(fatal, "You cannot have the yaml data_table if use_data_table_yaml=.false.")
 
    if (use_data_table_yaml) then
       call mpp_error(fatal, "You cannot have use_data_table_yaml=.true. without compiling with -Duse_yaml")
    else
 
       allocate(data_table(max_table))
       do i = 1, max_table
          data_table(i) = default_table
       enddo
       call read_table(data_table)
    end if
#endif
 
!  Initialize override array
    default_array%gridname = 'NONE'
    default_array%fieldname = 'NONE'
    default_array%t_index = -1
    default_array%dims = -1
    default_array%comp_domain = -1
    do i = 1, max_array
       override_array(i) = default_array
    enddo
    call time_interp_external_init
 end if
 
 module_is_initialized = .true.
 
 if ( .NOT. (atm_on .or. ocn_on .or. lnd_on .or. ice_on .or. lndug_on)) return
 if (table_size .eq. 0) then
    call mpp_error(note, "data_table is empty, not doing any data_overrides")
    return
 endif
 call fms2_io_init
 
! Test if grid_file is already opened
 inquire (file=trim(grid_file), opened=file_open)
 if(file_open) call mpp_error(fatal, trim(grid_file)//' already opened')
 
 if(.not. open_file(fileobj, grid_file, 'read' )) then
   call mpp_error(fatal, 'data_override_mod: Error in opening file '//trim(grid_file))
 endif
 
 if(variable_exists(fileobj, "x_T" ) .OR. variable_exists(fileobj, "geolon_t" ) ) then
   use_get_grid_version = 1
   call close_file(fileobj)
 else if(variable_exists(fileobj, "ocn_mosaic_file" ) .OR. variable_exists(fileobj, "gridfiles" ) ) then
   use_get_grid_version = 2
   if(variable_exists(fileobj, "gridfiles" ) ) then
     if(count_ne_1((ocn_on .OR. ice_on), lnd_on, atm_on)) call mpp_error(fatal, 'data_override_mod: the grid file ' //&
          'is a solo mosaic, one and only one of atm_on, lnd_on or ice_on/ocn_on should be true')
   end if
 else
   call mpp_error(fatal, 'data_override_mod: none of x_T, geolon_t, ocn_mosaic_file or gridfiles exist in '// &
                  & trim(grid_file))
 endif
 
 if(use_get_grid_version .EQ. 1) then
    if (atm_on .and. .not. allocated(lon_local_atm) ) then
       call mpp_get_compute_domain( atm_domain,is,ie,js,je)
       allocate(lon_local_atm(is:ie,js:je), lat_local_atm(is:ie,js:je))
       call get_grid_version_1(grid_file, 'atm', atm_domain, is, ie, js, je, lon_local_atm, lat_local_atm, &
          min_glo_lon_atm, max_glo_lon_atm )
    endif
    if (ocn_on .and. .not. allocated(lon_local_ocn) ) then
       call mpp_get_compute_domain( ocn_domain,is,ie,js,je)
       allocate(lon_local_ocn(is:ie,js:je), lat_local_ocn(is:ie,js:je))
       call get_grid_version_1(grid_file, 'ocn', ocn_domain, is, ie, js, je, lon_local_ocn, lat_local_ocn, &
          min_glo_lon_ocn, max_glo_lon_ocn )
    endif
 
    if (lnd_on .and. .not. allocated(lon_local_lnd) ) then
       call mpp_get_compute_domain( lnd_domain,is,ie,js,je)
       allocate(lon_local_lnd(is:ie,js:je), lat_local_lnd(is:ie,js:je))
       call get_grid_version_1(grid_file, 'lnd', lnd_domain, is, ie, js, je, lon_local_lnd, lat_local_lnd, &
          min_glo_lon_lnd, max_glo_lon_lnd )
    endif
 
    if (ice_on .and. .not. allocated(lon_local_ice) ) then
       call mpp_get_compute_domain( ice_domain,is,ie,js,je)
       allocate(lon_local_ice(is:ie,js:je), lat_local_ice(is:ie,js:je))
       call get_grid_version_1(grid_file, 'ice', ice_domain, is, ie, js, je, lon_local_ice, lat_local_ice, &
          min_glo_lon_ice, max_glo_lon_ice )
    endif
 else
   if (atm_on .and. .not. allocated(lon_local_atm) ) then
       call mpp_get_compute_domain(atm_domain,is,ie,js,je)
       allocate(lon_local_atm(is:ie,js:je), lat_local_atm(is:ie,js:je))
       call get_grid_version_2(fileobj, 'atm', atm_domain, is, ie, js, je, lon_local_atm, lat_local_atm, &
                               min_glo_lon_atm, max_glo_lon_atm )
   endif
 
   if (ocn_on .and. .not. allocated(lon_local_ocn) ) then
       call mpp_get_compute_domain( ocn_domain,is,ie,js,je)
       allocate(lon_local_ocn(is:ie,js:je), lat_local_ocn(is:ie,js:je))
       call get_grid_version_2(fileobj, 'ocn', ocn_domain, is, ie, js, je, lon_local_ocn, lat_local_ocn, &
                               min_glo_lon_ocn, max_glo_lon_ocn, use_center_grid_points)
   endif
 
   if (lnd_on .and. .not. allocated(lon_local_lnd) ) then
       call mpp_get_compute_domain( lnd_domain,is,ie,js,je)
       allocate(lon_local_lnd(is:ie,js:je), lat_local_lnd(is:ie,js:je))
       call get_grid_version_2(fileobj, 'lnd', lnd_domain, is, ie, js, je, lon_local_lnd, lat_local_lnd, &
                               min_glo_lon_lnd, max_glo_lon_lnd )
   endif
 
   if (ice_on .and. .not. allocated(lon_local_ice) ) then
       call mpp_get_compute_domain( ice_domain,is,ie,js,je)
       allocate(lon_local_ice(is:ie,js:je), lat_local_ice(is:ie,js:je))
       call get_grid_version_2(fileobj, 'ocn', ice_domain, is, ie, js, je, lon_local_ice, lat_local_ice, &
                               min_glo_lon_ice, max_glo_lon_ice, use_center_grid_points )
   endif
 end if
 if(use_get_grid_version .EQ. 2) then
   call close_file(fileobj)
 end if
end subroutine data_override_init_impl_
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!> @brief Implementation of the following truth table:
!!
!! Arg 1    Arg 2    Arg 3   | Result  !!
!!
!! .true.   .true.   .true.  | .true.  !!
!! .true.   .true.   .false. | .true.  !!
!! .true.   .false.  .true.  | .true.  !!
!! .true.   .false.  .false. | .false. !!
!! .false.  .true.   .true.  | .true.  !!
!! .false.  .true.   .false. | .false. !!
!! .false.  .false.  .true.  | .false. !!
!! .false.  .false.  .false. | .true.  !!
function count_ne_1(in_1, in_2, in_3)
  logical, intent(in)  :: in_1 !< Argument 1
  logical, intent(in)  :: in_2 !< Argument 2
  logical, intent(in)  :: in_3 !< Argument 3
  logical :: count_ne_1
 
  count_ne_1 = .not.(in_1.NEQV.in_2.NEQV.in_3) .OR. (in_1.AND.in_2.AND.in_3)
end function count_ne_1
 
subroutine read_table(data_table)
    type(data_type), dimension(max_table), intent(inout) :: data_table
 
    integer :: ntable
    integer :: ntable_lima
    integer :: ntable_new
 
    integer :: iunit
    integer :: io_status
    integer :: index_1col, index_2col
    character(len=256)    :: record
    type(data_type)  :: data_entry
 
    logical               :: ongrid
    logical               :: table_exists !< Flag indicating existence of data_table
    character(len=128)    :: region, region_type
 
    integer :: sunit
 
!  Read coupler_table
    inquire(file='data_table', exist=table_exists)
    if (.not. table_exists) then
      call mpp_error(note, 'data_override_mod: File data_table does not exist.')
      table_size = 0
      return
    end if
 
    open(newunit=iunit, file='data_table', action='READ', iostat=io_status)
    if(io_status/=0) call mpp_error(fatal, 'data_override_mod: Error in opening file data_table.')
 
    ntable = 0
    ntable_lima = 0
    ntable_new = 0
 
    do while (ntable <= max_table)
       read(iunit,'(a)',end=100) record
       if (record(1:1) == '#') cycle
       if (record(1:10) == '          ') cycle
       ntable=ntable+1
       if(index(lowercase(record), "inside_region") .ne. 0 .or. index(lowercase(record), "outside_region") .ne. 0) then
          if(index(lowercase(record), ".false.") .ne. 0 .or. index(lowercase(record), ".true.") .ne. 0 ) then
             ntable_lima = ntable_lima + 1
             read(record,*,err=99) data_entry%gridname, data_entry%fieldname_code, data_entry%fieldname_file, &
                                   data_entry%file_name, ongrid, data_entry%factor, region, region_type
             if(ongrid) then
                data_entry%interpol_method = 'none'
             else
                data_entry%interpol_method = 'bilinear'
             endif
          else
             ntable_new=ntable_new+1
             read(record,*,err=99) data_entry%gridname, data_entry%fieldname_code, data_entry%fieldname_file, &
                                   data_entry%file_name, data_entry%interpol_method, data_entry%factor, region, &
                                 & region_type
 
             if (index(data_entry%file_name, ":") .ne. 0) then
               data_entry%multifile = .true.
               index_1col = index(data_entry%file_name, ":")
               index_2col = index(data_entry%file_name(index_1col+1:), ":")
               if (index_2col .eq. 0) call mpp_error(fatal, "data_override: when bridging over forcing files, " &
                 // "central forcing files must be preceded AND followed by the column (:) separator")
               data_entry%prev_file_name = data_entry%file_name(1:index_1col-1)
               data_entry%next_file_name = data_entry%file_name(index_1col+index_2col+1:)
               ! once previous/next files are filled in, overwrite current
               data_entry%file_name = data_entry%file_name(index_1col+1:index_1col+index_2col-1)
             else
               data_entry%multifile = .false.
               data_entry%prev_file_name = ""
               data_entry%next_file_name = ""
             endif
             if (data_entry%interpol_method == 'default') then
                data_entry%interpol_method = default_table%interpol_method
             endif
             if (.not.(data_entry%interpol_method == 'default'  .or. &
                  data_entry%interpol_method == 'bicubic'  .or. &
                  data_entry%interpol_method == 'bilinear' .or. &
                  data_entry%interpol_method == 'none')) then
                sunit = stdout()
                write(sunit,*)" gridname is ", trim(data_entry%gridname)
                write(sunit,*)" fieldname_code is ", trim(data_entry%fieldname_code)
                write(sunit,*)" fieldname_file is ", trim(data_entry%fieldname_file)
                write(sunit,*)" file_name is ", trim(data_entry%file_name)
                write(sunit,*)" factor is ", data_entry%factor
                write(sunit,*)" interpol_method is ", trim(data_entry%interpol_method)
                call mpp_error(fatal, 'data_override_mod: invalid last entry in data_override_table, ' &
                     //'its value should be "default", "bicubic", "bilinear" or "none" ')
             endif
          endif
          if( trim(region_type) == "inside_region" ) then
             data_entry%region_type = inside_region
          else if( trim(region_type) == "outside_region" ) then
             data_entry%region_type = outside_region
          else
             call mpp_error(fatal, 'data_override_mod: region type should be inside_region or outside_region')
          endif
          if (data_entry%file_name == "") call mpp_error(fatal, &
              "data_override: filename not given in data_table when region_type is not NO_REGION")
          if(data_entry%fieldname_file == "") call mpp_error(fatal, &
             "data_override: fieldname_file must be specified in data_table when region_type is not NO_REGION")
          if( trim(data_entry%interpol_method) == 'none') call mpp_error(fatal, &
             "data_override(data_override_init): ongrid must be false when region_type is not NO_REGION")
          read(region,*) data_entry%lon_start, data_entry%lon_end, data_entry%lat_start, data_entry%lat_end
          !--- make sure data_entry%lon_end > data_entry%lon_start and data_entry%lat_end > data_entry%lat_start
          if(data_entry%lon_end .LE. data_entry%lon_start) call mpp_error(fatal, &
             "data_override: lon_end should be greater than lon_start")
          if(data_entry%lat_end .LE. data_entry%lat_start) call mpp_error(fatal, &
             "data_override: lat_end should be greater than lat_start")
       ! old format
       else if (index(lowercase(record), ".false.") .ne. 0 .or. index(lowercase(record), ".true.") .ne. 0 ) then
          ntable_lima = ntable_lima + 1
          read(record,*,err=99) data_entry%gridname, data_entry%fieldname_code, data_entry%fieldname_file, &
                                   data_entry%file_name, ongrid, data_entry%factor
          if (index(data_entry%file_name, ":") .ne. 0) then
            data_entry%multifile = .true.
            index_1col = index(data_entry%file_name, ":")
            index_2col = index(data_entry%file_name(index_1col+1:), ":")
            if (index_2col .eq. 0) call mpp_error(fatal, "data_override: when bridging over forcing files, " &
              // "central forcing files must be preceded AND followed by the column (:) separator")
            data_entry%prev_file_name = data_entry%file_name(1:index_1col-1)
            data_entry%next_file_name = data_entry%file_name(index_1col+index_2col+1:)
            ! once previous/next files are filled in, overwrite current
            data_entry%file_name = data_entry%file_name(index_1col+1:index_1col+index_2col-1)
          else
            data_entry%multifile = .false.
            data_entry%prev_file_name = ""
            data_entry%next_file_name = ""
          endif
          if(ongrid) then
             data_entry%interpol_method = 'none'
          else
             data_entry%interpol_method = 'bilinear'
          endif
          data_entry%lon_start = 0.0_lkind
          data_entry%lon_end   = -1.0_lkind
          data_entry%lat_start = 0.0_lkind
          data_entry%lat_end   = -1.0_lkind
          data_entry%region_type = no_region
       else                                      ! new format
          ntable_new=ntable_new+1
          read(record,*,err=99) data_entry%gridname, data_entry%fieldname_code, data_entry%fieldname_file, &
                                data_entry%file_name, data_entry%interpol_method, data_entry%factor
          if (index(data_entry%file_name, ":") .ne. 0) then
            index_1col = index(data_entry%file_name, ":")
            index_2col = index(data_entry%file_name(index_1col+1:), ":")
            data_entry%multifile = .true.
            if (index_2col .eq. 0) call mpp_error(fatal, "data_override: when bridging over forcing files, " &
              // "central forcing files must be preceded AND followed by the column (:) separator")
            data_entry%prev_file_name = data_entry%file_name(1:index_1col-1)
            data_entry%next_file_name = data_entry%file_name(index_1col+index_2col+1:)
            ! once previous/next files are filled in, overwrite current
            data_entry%file_name = data_entry%file_name(index_1col+1:index_1col+index_2col-1)
          else
            data_entry%multifile = .false.
            data_entry%prev_file_name = ""
            data_entry%next_file_name = ""
          endif
          if (data_entry%interpol_method == 'default') then
            data_entry%interpol_method = default_table%interpol_method
          endif
          if (.not.(data_entry%interpol_method == 'default'  .or. &
                    data_entry%interpol_method == 'bicubic'  .or. &
                    data_entry%interpol_method == 'bilinear' .or. &
                    data_entry%interpol_method == 'none')) then
             sunit = stdout()
             write(sunit,*)" gridname is ", trim(data_entry%gridname)
             write(sunit,*)" fieldname_code is ", trim(data_entry%fieldname_code)
             write(sunit,*)" fieldname_file is ", trim(data_entry%fieldname_file)
             write(sunit,*)" file_name is ", trim(data_entry%file_name)
             write(sunit,*)" factor is ", data_entry%factor
             write(sunit,*)" interpol_method is ", trim(data_entry%interpol_method)
             call mpp_error(fatal, 'data_override_mod: invalid last entry in data_override_table, ' &
                               //'its value should be "default", "bicubic", "bilinear" or "none" ')
          endif
          data_entry%lon_start = 0.0_lkind
          data_entry%lon_end   = -1.0_lkind
          data_entry%lat_start = 0.0_lkind
          data_entry%lat_end   = -1.0_lkind
          data_entry%region_type = no_region
       endif
       data_entry%ext_weights = .false.
       data_table(ntable) = data_entry
    enddo
    call mpp_error(fatal,'too many enries in data_table')
99  call mpp_error(fatal,'error in data_table format')
100 continue
    table_size = ntable
    if(ntable_new*ntable_lima /= 0) call mpp_error(fatal, &
       'data_override_mod: New and old formats together in same data_table not supported')
    close(iunit, iostat=io_status)
    if(io_status/=0) call mpp_error(fatal, 'data_override_mod: Error in closing file data_table')
end subroutine read_table
 
#ifdef use_yaml
!> @brief Read and parse the data_table.yaml
subroutine read_table_yaml(data_table)
    type(data_type), dimension(:), allocatable, intent(out) :: data_table !< Contents of the data_table.yaml
 
    integer, allocatable :: entry_id(:)
    integer :: sub_block_id(1), sub2_block_id(1)
    integer :: nentries, mentries
    integer :: i
    character(len=50) :: buffer
    character(len=FMS_FILE_LEN) :: filename !< Name of the expected data_table.yaml
    integer :: file_id
 
    ! If doing and ensemble or nest run add the filename appendix (ens_XX or nest_XX) to the filename
    call get_instance_filename("data_table.yaml", filename)
    if (index(trim(filename), "ens_") .ne. 0) then
      if (file_exists(filename) .and. file_exists("data_table.yaml")) &
        call mpp_error(fatal, "Both data_table.yaml and "//trim(filename)//" exists, pick one!")
 
      !< If the end_* file does not exist, revert back to "data_table.yaml"
      !! where every ensemble is using the same yaml
      if (.not. file_exists(filename)) filename = "data_table.yaml"
    endif
 
    file_id = open_and_parse_file(trim(filename))
 
    if (file_id==999) then
      nentries = 0
    else
      nentries = get_num_blocks(file_id, "data_table")
      allocate(data_table(nentries))
      allocate(entry_id(nentries))
      call get_block_ids(file_id, "data_table", entry_id)
 
      do i = 1, nentries
        call get_value_from_key(file_id, entry_id(i), "factor", data_table(i)%factor)
        call get_value_from_key(file_id, entry_id(i), "grid_name", data_table(i)%gridname)
        call check_for_valid_gridname(data_table(i)%gridname)
        call get_value_from_key(file_id, entry_id(i), "fieldname_in_model", data_table(i)%fieldname_code)
 
        mentries = get_num_blocks(file_id, "override_file", parent_block_id=entry_id(i))
        data_table(i)%file_name = ""
        data_table(i)%fieldname_file = ""
        data_table(i)%interpol_method = "none"
        data_table(i)%multifile = .false.
        data_table(i)%ext_weights = .false.
        data_table(i)%region_type = no_region
        data_table(i)%prev_file_name = ""
        data_table(i)%next_file_name = ""
        data_table(i)%ext_weights_file_name = ""
        data_table(i)%ext_weights_source = ""
 
        ! If there is no override_file block, then not overriding from file, so move on to the next entry
        if (mentries .eq. 0) cycle
 
        if(mentries.gt.1) call mpp_error(fatal, "Too many override_file blocks in data table. "//&
              "Check your data_table.yaml entry for field:"//trim(data_table(i)%gridname)//":"//&
              trim(data_table(i)%fieldname_code))
        call get_block_ids(file_id, "override_file", sub_block_id, parent_block_id=entry_id(i))
 
        call get_value_from_key(file_id, sub_block_id(1), "file_name", data_table(i)%file_name)
        call get_value_from_key(file_id, sub_block_id(1), "fieldname_in_file", data_table(i)%fieldname_file)
        call get_value_from_key(file_id, sub_block_id(1), "interp_method", data_table(i)%interpol_method)
        call check_interpol_method(data_table(i)%interpol_method, data_table(i)%file_name, &
              & data_table(i)%fieldname_file)
 
        mentries = get_num_blocks(file_id, "multi_file", parent_block_id=sub_block_id(1))
        if(mentries.gt.1) call mpp_error(fatal, "Too many multi_file blocks in tata table. "//&
              "Check your data_table.yaml entry for field:"//trim(data_table(i)%gridname)//":"//&
              trim(data_table(i)%fieldname_code))
 
        if(mentries.gt.0) data_table(i)%multifile = .true.
 
        if (data_table(i)%multifile) then
          call get_block_ids(file_id, "multi_file", sub2_block_id, parent_block_id=sub_block_id(1))
          call get_value_from_key(file_id, sub2_block_id(1), "prev_file_name", data_table(i)%prev_file_name)
          call get_value_from_key(file_id, sub2_block_id(1), "next_file_name", data_table(i)%next_file_name)
          if (trim(data_table(i)%prev_file_name) .eq. "" .and. trim(data_table(i)%next_file_name) .eq. "") &
            call mpp_error(fatal, "The prev_file_name and next_file_name must be present if is_multi_file. "//&
              "Check your data_table.yaml entry for field:"//trim(data_table(i)%gridname)//":"//&
              trim(data_table(i)%fieldname_code))
        endif
 
        mentries = get_num_blocks(file_id, "external_weights", parent_block_id=sub_block_id(1))
        if(mentries.gt.1) call mpp_error(fatal, "Too many external_weight blocks in data table. "//&
              "Check your data_table.yaml entry for field:"//trim(data_table(i)%gridname)//":"//&
              trim(data_table(i)%fieldname_code))
 
        if(mentries.gt.0) data_table(i)%ext_weights = .true.
 
        if (data_table(i)%ext_weights) then
          call get_block_ids(file_id, "external_weights", sub2_block_id, parent_block_id=sub_block_id(1))
          call get_value_from_key(file_id, sub2_block_id(1), "file_name", data_table(i)%ext_weights_file_name)
          call get_value_from_key(file_id, sub2_block_id(1), "source", data_table(i)%ext_weights_source)
          if (trim(data_table(i)%ext_weights_file_name) .eq. "" .and. trim(data_table(i)%ext_weights_source) .eq. "") &
            call mpp_error(fatal, "The file_name and source must be present when using external weights"//&
              "Check your data_table.yaml entry for field:"//trim(data_table(i)%gridname)//":"//&
              trim(data_table(i)%fieldname_code))
        endif
 
        mentries = get_num_blocks(file_id, "subregion", parent_block_id=entry_id(i))
        if(mentries.gt.1) call mpp_error(fatal, "Too many subregion blocks in data table. "//&
          "Check your data_table.yaml entry for field:"//trim(data_table(i)%gridname)//":"//&
          trim(data_table(i)%fieldname_code))
 
        buffer = ""
        if(mentries.gt.0) then
          call get_block_ids(file_id, "subregion", sub_block_id, parent_block_id=entry_id(i))
          call get_value_from_key(file_id, sub_block_id(1), "type", buffer)
        endif
 
        call check_and_set_region_type(buffer, data_table(i)%region_type)
        if (data_table(i)%region_type .ne. no_region) then
          call get_value_from_key(file_id, sub_block_id(1), "lon_start", data_table(i)%lon_start)
          call get_value_from_key(file_id, sub_block_id(1), "lon_end", data_table(i)%lon_end)
          call get_value_from_key(file_id, sub_block_id(1), "lat_start", data_table(i)%lat_start)
          call get_value_from_key(file_id, sub_block_id(1), "lat_end", data_table(i)%lat_end)
          call check_valid_lat_lon(data_table(i)%lon_start, data_table(i)%lon_end, &
                                   data_table(i)%lat_start, data_table(i)%lat_end)
        endif
      end do
 
    end if
    table_size = nentries !< Because one variable is not enough
end subroutine read_table_yaml
 
!> @brief Check if a grid name is valid, crashes if it is not
subroutine check_for_valid_gridname(gridname)
   character(len=*), intent(in) :: gridname !< Gridname
 
   select case(trim(gridname))
   case ("OCN", "ATM", "LND", "ICE")
   case default
      call mpp_error(fatal, trim(gridname)//" is not a valid gridname. "//&
         "The acceptable values are OCN ATM LND and ICE. Check your data_table.yaml")
   end select
end subroutine check_for_valid_gridname
 
!> @brief Check if the interpol method is correct, crashes if it is not
subroutine check_interpol_method(interp_method, filename, fieldname)
   character(len=*), intent(in) :: interp_method !< The interpo_method
   character(len=*), intent(in) :: filename      !< The filename
   character(len=*), intent(in) :: fieldname     !< The fieldname in the file
 
   select case(trim(interp_method))
   case ("bicubic", "bilinear")
      if (trim(filename) .eq. "" .or. trim(fieldname) .eq. "") call mpp_error(fatal, &
         "The file_name and the fieldname_file must be set if using the bicubic or bilinear interpolation method."//&
         " Check your data_table.yaml")
   case ("none")
      if (trim(filename) .ne. "" ) then
         if (trim(fieldname) .eq. "") call mpp_error(fatal, &
            "If the interpol_method is none and file_name is specified (ongrid case), "//&
            "you must also specify the fieldname_file")
      endif
   case default
      call mpp_error(fatal, trim(interp_method)//" is not a valid interp method. "//&
         "The acceptable values are bilinear and bicubic")
   end select
end subroutine check_interpol_method
 
!> @brief Check if a region_type is valid, crashes if it is not. Otherwise it sets the
!! correct integer parameter.
subroutine check_and_set_region_type(region_type_str, region_type_int)
   character(len=*), intent(in)  :: region_type_str !< The region type as defined in the data.yaml
   integer,          intent(out) :: region_type_int !< The region type as an integer parameter
 
   select case(trim(region_type_str))
   case ("inside_region")
      region_type_int = inside_region
   case ("outside_region")
      region_type_int = outside_region
   case ("")
      region_type_int = no_region
   case default
      call mpp_error(fatal, trim(region_type_str)//" is not a valid region type. "//&
         "The acceptable values are inside_region and outside_regioon. Check your data_table.yaml")
   end select
end subroutine check_and_set_region_type
 
!> @brief Check if a region lon_start, lon_end, lat_start and lat_end is valid.
!! Crashes if it is not.
subroutine check_valid_lat_lon(lon_start, lon_end, lat_start, lat_end)
   real(FMS_DATA_OVERRIDE_KIND_), intent(in) :: lon_start !< Starting longitude of the data_override region
   real(FMS_DATA_OVERRIDE_KIND_), intent(in) :: lon_end   !< Ending longitude of the data_override region
   real(FMS_DATA_OVERRIDE_KIND_), intent(in) :: lat_start !< Starting lattiude of the data_override region
   real(FMS_DATA_OVERRIDE_KIND_), intent(in) :: lat_end   !< Ending lattiude of the data_override region
 
   if (lon_start > lon_end) call mpp_error(fatal, &
      "lon_start:"//string(lon_start)//" is greater than lon_end"//string(lon_end)//&
      ". Check your data_table.yaml.")
 
   if (lat_start > lat_end) call mpp_error(fatal, &
      "lat_start:"//string(lat_start)//" is greater than lat_end:"//string(lat_end)//&
      ". Check your data_table.yaml.")
end subroutine check_valid_lat_lon
#endif
 
subroutine data_override_unset_atm_
  atm_domain = null_domain2d
  if (allocated(lon_local_atm)) deallocate(lon_local_atm)
  if (allocated(lat_local_atm)) deallocate(lat_local_atm)
end subroutine
 
subroutine data_override_unset_ocn_
  ocn_domain = null_domain2d
  if (allocated(lon_local_ocn)) deallocate(lon_local_ocn)
  if (allocated(lat_local_ocn)) deallocate(lat_local_ocn)
end subroutine
 
subroutine data_override_unset_lnd_
  lnd_domain = null_domain2d
  if (allocated(lon_local_lnd)) deallocate(lon_local_lnd)
  if (allocated(lat_local_lnd)) deallocate(lat_local_lnd)
end subroutine
 
subroutine data_override_unset_ice_
  ice_domain = null_domain2d
  if (allocated(lon_local_ice)) deallocate(lon_local_ice)
  if (allocated(lat_local_ice)) deallocate(lat_local_ice)
end subroutine
 
!> @brief Given a gridname, this routine returns the working domain associated with this gridname
subroutine get_domain(gridname, domain, comp_domain)
  character(len=3), intent(in) :: gridname
  type(domain2D), intent(inout) :: domain
  integer, intent(out), optional :: comp_domain(4) !< istart,iend,jstart,jend for compute domain
 
  domain = null_domain2d
  select case (gridname)
     case('OCN')
        domain = ocn_domain
     case('ATM')
        domain = atm_domain
     case('LND')
        domain = lnd_domain
     case('ICE')
        domain = ice_domain
     case default
        call mpp_error(fatal,'error in data_override get_domain')
  end select
  if(domain .EQ. null_domain2d) call mpp_error(fatal,'data_override: failure in get_domain')
  if(present(comp_domain)) &
     call mpp_get_compute_domain(domain,comp_domain(1),comp_domain(2),comp_domain(3),comp_domain(4))
end subroutine get_domain
 
!> @brief Given a gridname, this routine returns the working domain associated with this gridname
subroutine get_domainug(gridname, UGdomain, comp_domain)
  character(len=3), intent(in) :: gridname
  type(domainUG), intent(inout) :: UGdomain
  integer, intent(out), optional :: comp_domain(4) !< istart,iend,jstart,jend for compute domain
  type(domain2D), pointer :: SGdomain => null()
 
  ugdomain = null_domainug
  select case (gridname)
     case('LND')
        ugdomain = lnd_domainug
     case default
        call mpp_error(fatal,'error in data_override get_domain')
  end select
!  if(UGdomain .EQ. NULL_DOMAINUG) call mpp_error(FATAL,'data_override: failure in get_domain')
  if(present(comp_domain)) &
     call mpp_get_ug_sg_domain(ugdomain,sgdomain)
     call mpp_get_compute_domain(sgdomain,comp_domain(1),comp_domain(2),comp_domain(3),comp_domain(4))
end subroutine get_domainug
!===============================================================================================
 
!> @brief Routine to perform data override for scalar fields
subroutine data_override_0d_(gridname,fieldname_code,data_out,time,override,data_index)
  character(len=3), intent(in) :: gridname !< model grid ID (ocn,ice,atm,lnd)
  character(len=*), intent(in) :: fieldname_code !< field name as used in the model (may be
                                                 !! different from the name in NetCDF data file)
  logical, intent(out), optional :: override !< true if the field has been overriden succesfully
  type(time_type), intent(in) :: time !< (target) model time
  real(FMS_DATA_OVERRIDE_KIND_), intent(out) :: data_out !< output data array returned by this call
  integer, intent(in), optional :: data_index
 
  type(time_type)    :: first_record !< first record of "current" file
  type(time_type)    :: last_record !< last record of "current" file
  character(len=FMS_PATH_LEN) :: filename !< file containing source data
  character(len=FMS_PATH_LEN) :: prevfilename !< file containing previous source data, when using multiple files
  character(len=FMS_PATH_LEN) :: nextfilename !< file containing next source data, when using multiple files
  character(len=128) :: fieldname !< fieldname used in the data file
  integer :: index1 !< field index in data_table
  integer            :: dims(4)
  integer            :: prev_dims(4) !< dimensions of previous source data, when using multiple files
  integer            :: next_dims(4) !< dimensions of next source data, when using multiple files
  integer :: id_time !< index for time interp in override array
  integer            :: id_time_prev=-1 !< time index for previous file, when using multiple files
  integer            :: id_time_next=-1 !< time index for next file, when using multiple files
  integer :: curr_position !< position of the field currently processed in override_array
  integer :: i
  real(FMS_DATA_OVERRIDE_KIND_) :: factor
  logical :: multifile !< use multiple consecutive files for override
 
  if(.not.module_is_initialized) &
       call mpp_error(fatal,'Error: need to call data_override_init first')
 
!1  Look  for the data file in data_table
  if(PRESENT(override)) override = .false.
  if (present(data_index)) then
    index1 = data_index
  else
    index1 = -1
    do i = 1, table_size
       if( trim(gridname) /= trim(data_table(i)%gridname)) cycle
       if( trim(fieldname_code) /= trim(data_table(i)%fieldname_code)) cycle
       index1 = i                               ! field found
       exit
    enddo
    if(index1 .eq. -1) then
       if(debug_data_override) &
         call mpp_error(warning,'this field is NOT found in data_table: '//trim(fieldname_code))
       return  ! NO override was performed
    endif
  endif
 
  fieldname = data_table(index1)%fieldname_file ! fieldname in netCDF data file
  factor = data_table(index1)%factor
  multifile = data_table(index1)%multifile
 
  if(fieldname == "") then
     data_out = factor
     if(PRESENT(override)) override = .true.
     return
  else
     filename = data_table(index1)%file_name
     if (filename == "") call mpp_error(fatal,'data_override: filename not given in data_table')
     if (multifile) prevfilename = data_table(index1)%prev_file_name
     if (multifile) nextfilename = data_table(index1)%next_file_name
  endif
 
!3 Check if fieldname has been previously processed
!$OMP SINGLE
  curr_position = -1
  if(num_fields > 0 ) then
     do i = 1, num_fields
        if(trim(override_array(i)%gridname) /= trim(gridname))   cycle
        if(trim(override_array(i)%fieldname) /= trim(fieldname_code)) cycle
        curr_position = i
        exit
     enddo
  endif
 
  if(curr_position < 0) then ! the field has not been processed previously
     num_fields = num_fields + 1
     curr_position = num_fields
     ! record fieldname, gridname in override_array
     override_array(curr_position)%fieldname = fieldname_code
     override_array(curr_position)%gridname = gridname
     id_time = init_external_field(filename,fieldname,verbose=debug_data_override)
     if(id_time<0) call mpp_error(fatal,'data_override:field not found in init_external_field 1')
     override_array(curr_position)%t_index = id_time
  else !curr_position >0
     !9 Get id_time  previously stored in override_array
     id_time = override_array(curr_position)%t_index
  endif !if curr_position < 0
 
 
  ! if using consecutive files for data_override, get time axis for previous and next files
  ! and check spatial dims for consistency
  if_multi1: if (multifile) then
    id_time_prev = -1
    if_prev1: if (trim(prevfilename) /= '') then
      id_time_prev = init_external_field(prevfilename,fieldname,verbose=debug_data_override)
      dims = get_external_field_size(id_time)
      prev_dims = get_external_field_size(id_time_prev)
      ! check consistency of spatial dims
      if ((prev_dims(1) .ne. dims(1)) .or. (prev_dims(2) .ne. dims(2)) .or. &
          (prev_dims(3) .ne. dims(3))) then
        call mpp_error(fatal, 'data_override: dimensions mismatch between consecutive forcing files')
      endif
      allocate(data_table(index1)%time_prev_records(prev_dims(4)))
      call get_time_axis(id_time_prev,data_table(index1)%time_prev_records)
    endif if_prev1
    id_time_next = -1
    if_next1: if (trim(nextfilename) /= '') then
      id_time_next = init_external_field(nextfilename,fieldname,verbose=debug_data_override)
      dims = get_external_field_size(id_time)
      next_dims = get_external_field_size(id_time_next)
      ! check consistency of spatial dims
      if ((next_dims(1) .ne. dims(1)) .or. (next_dims(2) .ne. dims(2)) .or. &
          (next_dims(3) .ne. dims(3))) then
        call mpp_error(fatal, 'data_override: dimensions mismatch between consecutive forcing files')
      endif
      allocate(data_table(index1)%time_next_records(next_dims(4)))
      call get_time_axis(id_time_next,data_table(index1)%time_next_records)
    endif if_next1
  endif if_multi1
 
 
  !10 do time interp to get data in compute_domain
 
  ! if using consecutive files, allow to perform time interpolation between the last record of previous
  ! file and first record of current file OR between the last record of current file and first record of
  ! next file hence "bridging" over files.
  if_multi2: if (multifile) then
    dims = get_external_field_size(id_time)
    if (.not. allocated(data_table(index1)%time_records)) allocate(data_table(index1)%time_records(dims(4)))
    call get_time_axis(id_time,data_table(index1)%time_records)
 
    first_record = data_table(index1)%time_records(1)
    last_record = data_table(index1)%time_records(dims(4))
 
    if_time2: if (time<first_record) then
      if (id_time_prev<0) call mpp_error(fatal,'data_override:previous file needed with multifile')
      prev_dims = get_external_field_size(id_time_prev)
      if (time<data_table(index1)%time_prev_records(prev_dims(4))) call mpp_error(fatal, &
          'data_override: time_interp_external_bridge should only be called to bridge with previous file')
      call time_interp_external_bridge(id_time_prev, id_time,time,data_out,verbose=debug_data_override)
    elseif (time>last_record) then
      if (id_time_next<0) call mpp_error(fatal,'data_override:next file needed with multifile')
      if (time>data_table(index1)%time_next_records(1)) call mpp_error(fatal, &
          'data_override: time_interp_external_bridge should only be called to bridge with next file')
      call time_interp_external_bridge(id_time, id_time_next,time,data_out,verbose=debug_data_override)
    else ! first_record < time < last_record, do not use bridge
      call time_interp_external(id_time,time,data_out,verbose=debug_data_override)
    endif if_time2
  else ! standard behavior
     call time_interp_external(id_time,time,data_out,verbose=debug_data_override)
  endif if_multi2
 
 
  data_out = data_out*factor
!$OMP END SINGLE
 
  if(PRESENT(override)) override = .true.
 
end subroutine data_override_0d_
 
!> @brief This routine performs data override for 2D fields.
subroutine data_override_2d_(gridname,fieldname,data_2D,time,override, is_in, ie_in, js_in, je_in)
  character(len=3), intent(in) :: gridname !< model grid ID
  character(len=*), intent(in) :: fieldname !< field to override
  logical, intent(out), optional :: override !< true if the field has been overriden succesfully
  type(time_type), intent(in) :: time !<  model time
  real(FMS_DATA_OVERRIDE_KIND_), dimension(:,:), intent(inout) :: data_2D !< data returned by this call
  integer,           optional,  intent(in) :: is_in, ie_in, js_in, je_in
  real(FMS_DATA_OVERRIDE_KIND_), dimension(:,:,:), allocatable ::  data_3D
  integer       :: index1
  integer       :: i
 
!1  Look  for the data file in data_table
  if(PRESENT(override)) override = .false.
  index1 = -1
  do i = 1, table_size
     if( trim(gridname) /= trim(data_table(i)%gridname)) cycle
     if( trim(fieldname) /= trim(data_table(i)%fieldname_code)) cycle
     index1 = i                               ! field found
     exit
  enddo
  if(index1 .eq. -1) return  ! NO override was performed
 
  allocate(data_3d(size(data_2d,1),size(data_2d,2),1))
  data_3d(:,:,1) = data_2d
  call data_override_3d_(gridname,fieldname,data_3d,time,override,data_index=index1,&
                       is_in=is_in,ie_in=ie_in,js_in=js_in,je_in=je_in)
 
  data_2d(:,:) = data_3d(:,:,1)
  deallocate(data_3d)
end subroutine data_override_2d_
 
!> @brief This routine performs data override for 3D fields
subroutine data_override_3d_(gridname,fieldname_code,return_data,time,override,data_index, is_in, ie_in, js_in, je_in)
  character(len=3),             intent(in) :: gridname !< model grid ID
  character(len=*),             intent(in) :: fieldname_code !< field name as used in the model
  logical,           optional, intent(out) :: override !< true if the field has been overriden succesfully
  type(time_type),              intent(in) :: time !< (target) model time
  integer,           optional,  intent(in) :: data_index
  real(FMS_DATA_OVERRIDE_KIND_), dimension(:,:,:), intent(inout) :: return_data !< data returned by this call
  integer,           optional,  intent(in) :: is_in, ie_in, js_in, je_in
  logical, dimension(:,:,:),   allocatable :: mask_out
 
  character(len=FMS_PATH_LEN) :: filename !< file containing source data
  character(len=FMS_PATH_LEN) :: filename2 !< file containing source data
  character(len=FMS_PATH_LEN) :: prevfilename !< file containing source data for previous file
  character(len=FMS_PATH_LEN) :: prevfilename2 !< file containing source data for previous file
  character(len=FMS_PATH_LEN) :: nextfilename !< file containing source data for next file
  character(len=FMS_PATH_LEN) :: nextfilename2 !< file containing source data for next file
  character(len=128) :: fieldname !< fieldname used in the data file
  integer            :: i,j
  integer            :: dims(4)
  integer            :: prev_dims(4) !< dimensions of previous source data, when using multiple files
  integer            :: next_dims(4) !< dimensions of next source data, when using multiple files
  integer            :: index1 !< field index in data_table
  integer            :: id_time !< index for time interp in override array
  integer            :: id_time_prev=-1 !< time index for previous file, when using multiple files
  integer            :: id_time_next=-1 !< time index for next file, when using multiple files
  integer            :: axis_sizes(4)
  character(len=32)  :: axis_names(4)
  real(FMS_DATA_OVERRIDE_KIND_), dimension(:,:), pointer :: lon_local =>null() !< of output (target) grid cells
  real(FMS_DATA_OVERRIDE_KIND_), dimension(:,:), pointer :: lat_local =>null() !< of output (target) grid cells
  real(FMS_DATA_OVERRIDE_KIND_), dimension(:), allocatable :: lon_tmp, lat_tmp
 
  logical :: data_file_is_2D = .false.  !< data in netCDF file is 2D
  logical :: ongrid, use_comp_domain
  type(domain2D) :: domain
  type(time_type)    :: first_record !< first record of "current" file
  type(time_type)    :: last_record !< last record of "current" file
  integer :: curr_position !< position of the field currently processed in override_array
  real(FMS_DATA_OVERRIDE_KIND_) :: factor
  integer, dimension(4) :: comp_domain = 0  !< istart,iend,jstart,jend for compute domain
  integer :: nxd, nyd, nxc, nyc, nwindows
  integer :: nwindows_x, ipos, jpos, window_size(2)
  integer :: istart, iend, jstart, jend
  integer :: isw, iew, jsw, jew
  integer :: omp_get_num_threads, window_id
  logical :: need_compute
  real(FMS_DATA_OVERRIDE_KIND_) :: lat_min, lat_max
  integer :: is_src, ie_src, js_src, je_src
  logical :: exists
  logical :: multifile !< use multiple consecutive files for override
  type(FmsNetcdfFile_t) :: fileobj
  integer :: startingi !< Starting x index for the compute domain relative to the input buffer
  integer :: endingi !< Ending x index for the compute domain relative to the input buffer
  integer :: startingj !< Starting y index for the compute domain relative to the input buffer
  integer :: endingj !< Ending y index for the compute domain relative to the input buffer
  integer :: nhalox !< Number of halos in the x direction
  integer :: nhaloy !< Number of halos in the y direction
  logical :: found_weight_file !< .True. if the weight file has already been read
  integer :: nglat !< Number of latitudes in the global domain
  integer :: nglon !< Number of longitudes in the global domain
 
  use_comp_domain = .false.
  if(.not.module_is_initialized) &
       call mpp_error(fatal,'Error: need to call data_override_init first')
 
!1  Look  for the data file in data_table
  if(PRESENT(override)) override = .false.
  if (present(data_index)) then
    index1 = data_index
  else
    index1 = -1
    do i = 1, table_size
       if( trim(gridname) /= trim(data_table(i)%gridname)) cycle
       if( trim(fieldname_code) /= trim(data_table(i)%fieldname_code)) cycle
       index1 = i                               ! field found
       exit
    enddo
    if(index1 .eq. -1) then
       if(debug_data_override) &
         call mpp_error(warning,'this field is NOT found in data_table: '//trim(fieldname_code))
       return  ! NO override was performed
    endif
  endif
 
  fieldname = data_table(index1)%fieldname_file ! fieldname in netCDF data file
  factor = data_table(index1)%factor
  multifile = data_table(index1)%multifile
 
  if(fieldname == "") then
     return_data = factor
     if(PRESENT(override)) override = .true.
     return
  else
     filename = data_table(index1)%file_name
     if (filename == "") call mpp_error(fatal,'data_override: filename not given in data_table')
     if (multifile) prevfilename = data_table(index1)%prev_file_name
     if (multifile) nextfilename = data_table(index1)%next_file_name
  endif
 
  ongrid = (data_table(index1)%interpol_method == 'none')
 
!3 Check if fieldname has been previously processed
!$OMP CRITICAL
  curr_position = -1
  if(num_fields > 0 ) then
     do i = 1, num_fields
        if(trim(override_array(i)%gridname) /= trim(gridname))   cycle
        if(trim(override_array(i)%fieldname) /= trim(fieldname_code)) cycle
        curr_position = i
        exit
     enddo
  endif
 
  if(curr_position < 0) then ! the field has not been processed previously
     num_fields = num_fields + 1
     curr_position = num_fields
 
! Get working domain from model's gridname
     call get_domain(gridname,domain,comp_domain)
     call mpp_get_data_domain(domain, xsize=nxd, ysize=nyd)
     nxc = comp_domain(2)-comp_domain(1) + 1
     nyc = comp_domain(4)-comp_domain(3) + 1
 
! record fieldname, gridname in override_array
     override_array(curr_position)%fieldname = fieldname_code
     override_array(curr_position)%gridname = gridname
     override_array(curr_position)%comp_domain = comp_domain
! get number of threads
     override_array(curr_position)%numthreads = 1
#if defined(_OPENMP)
     override_array(curr_position)%numthreads = omp_get_num_threads()
#endif
!--- data_override may be called from physics windows. The following are possible situations
!--- 1. size(return_data,1) == nxd and size(return_data,2) == nyd
!---    (on return_data domain and there is only one window).
!--- 2. nxc is divisible by size(return_data,1), nyc is divisible by size(return_data,2),
!---    nwindow = (nxc/size(return_data(1))*(nyc/size(return_data,2)),
!---    also we require nwindows is divisible by nthreads.
!---    The another restrition is that size(return_data,1) == ie_in - is_in + 1,
!---                                   size(return_data,2) == je_in - js_in + 1
     nwindows = 1
     if( nxd == size(return_data,1) .AND. nyd == size(return_data,2) ) then  !
        use_comp_domain = .false.
     else if ( mod(nxc, size(return_data,1)) ==0 .AND. mod(nyc, size(return_data,2)) ==0 ) then
        use_comp_domain = .true.
        nwindows = (nxc/size(return_data,1))*(nyc/size(return_data,2))
     else
        call mpp_error(fatal, &
                     & "data_override: data is not on data domain and compute domain is not divisible by size(data)")
     endif
     override_array(curr_position)%window_size(1) = size(return_data,1)
     override_array(curr_position)%window_size(2) = size(return_data,2)
 
     window_size = override_array(curr_position)%window_size
     override_array(curr_position)%numwindows = nwindows
     if( mod(nwindows, override_array(curr_position)%numthreads) .NE. 0 ) then
        call mpp_error(fatal, "data_override: nwindow is not divisible by nthreads")
     endif
     allocate(override_array(curr_position)%need_compute(nwindows))
     override_array(curr_position)%need_compute = .true.
 
!4 get index for time interp
     if(ongrid) then
        if( data_table(index1)%region_type .NE. no_region ) then
           call mpp_error(fatal,.NE.'data_override: ongrid must be false when region_type  NO_REGION')
        endif
 
!  Allow on-grid data_overrides on cubed sphere grid
        inquire(file=trim(filename),exist=exists)
        if (.not. exists) then
           call get_mosaic_tile_file(filename,filename2,.false.,domain)
           filename = filename2
        endif
 
        ! if using consecutive files for data_override, get file names
        if_multi3: if (multifile) then
          if_prev3: if (trim(prevfilename) /= '') then
            inquire(file=trim(prevfilename),exist=exists)
            if (.not. exists) then
               call get_mosaic_tile_file(prevfilename,prevfilename2,.false.,domain)
               prevfilename = prevfilename2
            endif
          endif if_prev3
          if_next3: if (trim(nextfilename) /= '') then
            inquire(file=trim(nextfilename),exist=exists)
            if (.not. exists) then
               call get_mosaic_tile_file(nextfilename,nextfilename2,.false.,domain)
               nextfilename = nextfilename2
            endif
          endif if_next3
        endif if_multi3
 
        !--- we always only pass data on compute domain
        id_time = init_external_field(filename,fieldname,domain=domain,verbose=debug_data_override, &
                                    use_comp_domain=use_comp_domain, nwindows=nwindows, ongrid=ongrid)
 
        ! if using consecutive files for data_override, get time axis for previous and next files
        ! and check spatial dims for consistency
        if_multi4: if (multifile) then
          id_time_prev = -1
          if_prev4:if (trim(prevfilename) /= '') then
            id_time_prev = init_external_field(prevfilename,fieldname,domain=domain, &
               verbose=debug_data_override,use_comp_domain=use_comp_domain, &
               nwindows = nwindows, ongrid=ongrid)
            dims = get_external_field_size(id_time)
            prev_dims = get_external_field_size(id_time_prev)
            ! check consistency of spatial dims
            if ((prev_dims(1) .ne. dims(1)) .or. (prev_dims(2) .ne. dims(2)) .or. &
                (prev_dims(3) .ne. dims(3))) then
              call mpp_error(fatal, 'data_override: dimensions mismatch between consecutive forcing files')
            endif
            allocate(data_table(index1)%time_prev_records(prev_dims(4)))
            call get_time_axis(id_time_prev,data_table(index1)%time_prev_records)
          endif if_prev4
          id_time_next = -1
          if_next4: if (trim(nextfilename) /= '') then
            id_time_next = init_external_field(nextfilename,fieldname,domain=domain, &
               verbose=debug_data_override,use_comp_domain=use_comp_domain, &
               nwindows = nwindows, ongrid=ongrid)
            dims = get_external_field_size(id_time)
            next_dims = get_external_field_size(id_time_next)
            ! check consistency of spatial dims
            if ((next_dims(1) .ne. dims(1)) .or. (next_dims(2) .ne. dims(2)) .or. &
                (next_dims(3) .ne. dims(3))) then
              call mpp_error(fatal, 'data_override: dimensions mismatch between consecutive forcing files')
            endif
            allocate(data_table(index1)%time_next_records(next_dims(4)))
            call get_time_axis(id_time_next,data_table(index1)%time_next_records)
          endif if_next4
        endif if_multi4
 
        dims = get_external_field_size(id_time)
        override_array(curr_position)%dims = dims
        if(id_time<0) call mpp_error(fatal,'data_override:field not found in init_external_field 1')
        override_array(curr_position)%t_index = id_time
        override_array(curr_position)%pt_index = id_time_prev
        override_array(curr_position)%nt_index = id_time_next
     else !ongrid=false
        id_time = init_external_field(filename,fieldname,domain=domain, axis_names=axis_names,&
            axis_sizes=axis_sizes, verbose=debug_data_override,override=.true.,use_comp_domain=use_comp_domain, &
            nwindows = nwindows)
 
        ! if using consecutive files for data_override, get time axis for previous and next files
        ! and check spatial dims for consistency
        if_multi5: if (multifile) then
          id_time_prev = -1
          if_prev5: if (trim(prevfilename) /= '') then
            id_time_prev = init_external_field(prevfilename,fieldname,domain=domain, axis_names=axis_names,&
               axis_sizes=axis_sizes, verbose=debug_data_override,override=.true.,use_comp_domain=use_comp_domain, &
               nwindows = nwindows)
            prev_dims = get_external_field_size(id_time_prev)
            allocate(data_table(index1)%time_prev_records(prev_dims(4)))
            call get_time_axis(id_time_prev,data_table(index1)%time_prev_records)
          endif if_prev5
          id_time_next = -1
          if_next5: if (trim(nextfilename) /= '') then
            id_time_next = init_external_field(nextfilename,fieldname,domain=domain, axis_names=axis_names,&
               axis_sizes=axis_sizes, verbose=debug_data_override,override=.true.,use_comp_domain=use_comp_domain, &
               nwindows = nwindows)
            next_dims = get_external_field_size(id_time_next)
            allocate(data_table(index1)%time_next_records(next_dims(4)))
            call get_time_axis(id_time_next,data_table(index1)%time_next_records)
          endif if_next5
        endif if_multi5
 
        dims = get_external_field_size(id_time)
        override_array(curr_position)%dims = dims
        if(id_time<0) call mpp_error(fatal,'data_override:field not found in init_external_field 2')
        override_array(curr_position)%t_index = id_time
        override_array(curr_position)%pt_index = id_time_prev
        override_array(curr_position)%nt_index = id_time_next
 
        !  get lon and lat of the input (source) grid, assuming that axis%data contains
        !  lat and lon of the input grid (in degrees)
 
        allocate(override_array(curr_position)%horz_interp(nwindows))
        allocate(override_array(curr_position)%lon_in(axis_sizes(1)+1))
        allocate(override_array(curr_position)%lat_in(axis_sizes(2)+1))
        if(get_external_fileobj(filename, fileobj)) then
           call axis_edges(fileobj, axis_names(1), override_array(curr_position)%lon_in, &
              reproduce_null_char_bug_flag=reproduce_null_char_bug)
           call axis_edges(fileobj, axis_names(2), override_array(curr_position)%lat_in, &
              reproduce_null_char_bug_flag=reproduce_null_char_bug)
        else
           call mpp_error(fatal,'data_override: file '//trim(filename)//' is not opened in time_interp_external')
        end if
! convert lon_in and lat_in from deg to radian
        override_array(curr_position)%lon_in = override_array(curr_position)%lon_in * real(deg_to_rad, lkind)
        override_array(curr_position)%lat_in = override_array(curr_position)%lat_in * real(deg_to_rad, lkind)
 
        !--- find the region of the source grid that cover the local model grid.
        !--- currently we only find the index range for j-direction because
        !--- of the cyclic condition in i-direction. The purpose of this is to
        !--- decrease the memory usage and increase the IO performance.
        select case(gridname)
        case('OCN')
           lon_local => lon_local_ocn; lat_local => lat_local_ocn
        case('ICE')
           lon_local => lon_local_ice; lat_local => lat_local_ice
        case('ATM')
           lon_local => lon_local_atm; lat_local => lat_local_atm
        case('LND')
           lon_local => lon_local_lnd; lat_local => lat_local_lnd
        case default
           call mpp_error(fatal,'error: gridname not recognized in data_override')
        end select
 
        lat_min = minval(lat_local)
        lat_max = maxval(lat_local)
        is_src = 1
        ie_src = axis_sizes(1)
        js_src = 1
        je_src = axis_sizes(2)
        ! do j = 1, axis_sizes(2)+1
        !    if( override_array(curr_position)%lat_in(j) > lat_min ) exit
        !    js_src = j
        ! enddo
        ! do j = 1, axis_sizes(2)+1
        !    je_src = j
        !    if( override_array(curr_position)%lat_in(j) > lat_max ) exit
        ! enddo
 
        !--- bicubic interpolation need one extra point in each direction. Also add
        !--- one more point for because lat_in is in the corner but the interpolation
        !--- use center points.
        select case (data_table(index1)%interpol_method)
        case ('bilinear')
           js_src = max(1, js_src-1)
           je_src = min(axis_sizes(2), je_src+1)
        case ('bicubic')
           js_src = max(1, js_src-2)
           je_src = min(axis_sizes(2), je_src+2)
        end select
        override_array(curr_position)%is_src = is_src
        override_array(curr_position)%ie_src = ie_src
        override_array(curr_position)%js_src = js_src
        override_array(curr_position)%je_src = je_src
        call reset_src_data_region(id_time, is_src, ie_src, js_src, je_src)
        if (multifile) then
          if (trim(prevfilename) /= '') then
            call reset_src_data_region(id_time_prev, is_src, ie_src, js_src, je_src)
          endif
          if (trim(nextfilename) /= '') then
            call reset_src_data_region(id_time_next, is_src, ie_src, js_src, je_src)
          endif
        endif
 
!       Find the index of lon_start, lon_end, lat_start and lat_end in the input grid (nearest points)
        if( data_table(index1)%region_type .NE. no_region ) then
           allocate( lon_tmp(axis_sizes(1)), lat_tmp(axis_sizes(2)) )
           call read_data(fileobj, axis_names(1), lon_tmp)
           call read_data(fileobj, axis_names(2), lat_tmp)
           ! limit lon_start, lon_end are inside lon_in
           !       lat_start, lat_end are inside lat_in
           if(data_table(index1)%lon_start < lon_tmp(1) .OR. data_table(index1)%lon_start .GT. lon_tmp(axis_sizes(1)))&
              call mpp_error(fatal, "data_override: lon_start is outside lon_T")
           if( data_table(index1)%lon_end < lon_tmp(1) .OR. data_table(index1)%lon_end .GT. lon_tmp(axis_sizes(1))) &
              call mpp_error(fatal, "data_override: lon_end is outside lon_T")
           if(data_table(index1)%lat_start < lat_tmp(1) .OR. data_table(index1)%lat_start .GT. lat_tmp(axis_sizes(2)))&
              call mpp_error(fatal, "data_override: lat_start is outside lat_T")
           if( data_table(index1)%lat_end < lat_tmp(1) .OR. data_table(index1)%lat_end .GT. lat_tmp(axis_sizes(2))) &
              call mpp_error(fatal, "data_override: lat_end is outside lat_T")
           istart = nearest_index(data_table(index1)%lon_start, lon_tmp)
           iend   = nearest_index(data_table(index1)%lon_end,   lon_tmp)
           jstart = nearest_index(data_table(index1)%lat_start, lat_tmp)
           jend   = nearest_index(data_table(index1)%lat_end,   lat_tmp)
           ! adjust the index according to is_src and js_src
           istart = istart - is_src + 1
           iend   = iend   - is_src + 1
           jstart = jstart - js_src + 1
           jend   = jend   - js_src + 1
           call set_override_region(id_time, data_table(index1)%region_type, istart, iend, jstart, jend)
           if (multifile) then
             if (trim(prevfilename) /= '') then
               call set_override_region(id_time_prev, data_table(index1)%region_type, istart, iend, jstart, jend)
             endif
             if (trim(nextfilename) /= '') then
               call set_override_region(id_time_next, data_table(index1)%region_type, istart, iend, jstart, jend)
             endif
           endif
           deallocate(lon_tmp, lat_tmp)
        endif
 
     endif !ongrid
  else !curr_position >0
     dims = override_array(curr_position)%dims
     comp_domain = override_array(curr_position)%comp_domain
     nxc = comp_domain(2)-comp_domain(1) + 1
     nyc = comp_domain(4)-comp_domain(3) + 1
     is_src      = override_array(curr_position)%is_src
     ie_src      = override_array(curr_position)%ie_src
     js_src      = override_array(curr_position)%js_src
     je_src      = override_array(curr_position)%je_src
     window_size = override_array(curr_position)%window_size
     !---make sure data size match window_size
     if( window_size(1) .NE. size(return_data,1) .OR. window_size(2) .NE. size(return_data,2) ) then
        call mpp_error(fatal, "data_override: window_size does not match size(data)")
     endif
!9 Get id_time  previously stored in override_array
     id_time = override_array(curr_position)%t_index
     id_time_prev = override_array(curr_position)%pt_index
     id_time_next = override_array(curr_position)%nt_index
  endif
!$OMP END CRITICAL
 
  if( override_array(curr_position)%numwindows > 1 ) then
      if( .NOT. PRESENT(is_in) .OR. .NOT. PRESENT(is_in) .OR. .NOT. PRESENT(is_in) .OR. .NOT. PRESENT(is_in) ) then
          call mpp_error(fatal, "data_override: is_in, ie_in, js_in, je_in must be present when nwindows > 1")
      endif
  endif
 
  isw = comp_domain(1)
  iew = comp_domain(2)
  jsw = comp_domain(3)
  jew = comp_domain(4)
  window_id = 1
  if( override_array(curr_position)%numwindows > 1 ) then
     nxc = comp_domain(2) - comp_domain(1) + 1
     nwindows_x = nxc/window_size(1)
     ipos = (is_in-1)/window_size(1) + 1
     jpos = (js_in-1)/window_size(2)
 
     window_id = jpos*nwindows_x + ipos
     isw = isw + is_in - 1
     iew = isw + ie_in - is_in
     jsw = jsw + js_in - 1
     jew = jsw + je_in - js_in
  endif
 
  if( ongrid ) then
     need_compute = .false.
  else
     !--- find the index for windows.
     need_compute=override_array(curr_position)%need_compute(window_id)
  endif
 
  !--- call horiz_interp_new is not initialized
 
  if( need_compute ) then
     select case(gridname)
     case('OCN')
        lon_local => lon_local_ocn; lat_local => lat_local_ocn
     case('ICE')
        lon_local => lon_local_ice; lat_local => lat_local_ice
     case('ATM')
        lon_local => lon_local_atm; lat_local => lat_local_atm
     case('LND')
        lon_local => lon_local_lnd; lat_local => lat_local_lnd
     case default
        call mpp_error(fatal,'error: gridname not recognized in data_override')
     end select
 
     if (data_table(index1)%ext_weights) then
      found_weight_file = .false.
      do i = 1, nweight_files
        if (external_weights(i)%weight_filename .eq. trim(data_table(index1)%ext_weights_file_name)) then
          override_array(curr_position)%horz_interp(window_id) = external_weights(i)%horiz_interp
          found_weight_file = .true.
          exit
        endif
      enddo
 
      if (.not. found_weight_file) then
        nweight_files = nweight_files + 1
        external_weights(nweight_files)%weight_filename = trim(data_table(index1)%ext_weights_file_name)
 
        call mpp_get_global_domain(domain, xsize=nglon, ysize=nglat)
        call horiz_interp_read_weights(external_weights(nweight_files)%horiz_interp, &
          external_weights(nweight_files)%weight_filename, &
          lon_local(isw:iew,jsw:jew), lat_local(isw:iew,jsw:jew), &
          override_array(curr_position)%lon_in(is_src:ie_src+1), &
          override_array(curr_position)%lat_in(js_src:je_src+1), &
          data_table(index1)%ext_weights_source, &
          data_table(index1)%interpol_method, isw, iew, jsw, jew, nglon, nglat)
 
        override_array(curr_position)%horz_interp(window_id) = external_weights(nweight_files)%horiz_interp
      endif
     else
      select case (data_table(index1)%interpol_method)
      case ('bilinear')
        call horiz_interp_new (override_array(curr_position)%horz_interp(window_id), &
             override_array(curr_position)%lon_in(is_src:ie_src+1),                  &
             override_array(curr_position)%lat_in(js_src:je_src+1),                  &
             lon_local(isw:iew,jsw:jew), lat_local(isw:iew,jsw:jew), interp_method="bilinear")
      case ('bicubic')
        call horiz_interp_new (override_array(curr_position)%horz_interp(window_id), &
             override_array(curr_position)%lon_in(is_src:ie_src+1),                  &
             override_array(curr_position)%lat_in(js_src:je_src+1),                  &
             lon_local(isw:iew,jsw:jew), lat_local(isw:iew,jsw:jew), interp_method="bicubic")
      end select
    endif
     override_array(curr_position)%need_compute(window_id) = .false.
  endif
 
  ! Determine if  data in netCDF file is 2D or not
  data_file_is_2d = .false.
  if((dims(3) == 1) .and. (size(return_data,3)>1)) data_file_is_2d = .true.
 
  if(dims(3) .NE. 1 .and. (size(return_data,3) .NE. dims(3))) &
      call mpp_error(fatal, .NE..NE."data_override: dims(3)  1 and size(return_data,3)  dims(3)")
 
 
  dims = get_external_field_size(id_time)
  if (.not. allocated(data_table(index1)%time_records)) allocate(data_table(index1)%time_records(dims(4)))
  call get_time_axis(id_time,data_table(index1)%time_records)
 
  first_record = data_table(index1)%time_records(1)
  last_record = data_table(index1)%time_records(dims(4))
 
  if(ongrid) then
    if (.not. use_comp_domain) then
        !< Determine the size of the halox and the part of `data` that is in the compute domain
        nhalox = (size(return_data,1) - nxc)/2
        nhaloy = (size(return_data,2) - nyc)/2
        startingi = lbound(return_data,1) + nhalox
        startingj = lbound(return_data,2) + nhaloy
        endingi   = ubound(return_data,1) - nhalox
        endingj   = ubound(return_data,2) - nhaloy
    end if
 
!10 do time interp to get data in compute_domain
    if(data_file_is_2d) then
      if (use_comp_domain) then
 
        ! if using consecutive files, allow to perform time interpolation between the last record of previous
        ! file and first record of current file OR between the last record of current file and first record of
        ! next file hence "bridging" over files.
        if_multi6: if (multifile) then
          if_time6: if (time<first_record) then
            ! previous file must be init and time must be between last record of previous file and
            ! first record of current file
            if (id_time_prev<0) call mpp_error(fatal,'data_override:previous file needed with multifile')
            prev_dims = get_external_field_size(id_time_prev)
            if (time<data_table(index1)%time_prev_records(prev_dims(4))) call mpp_error(fatal, &
                'data_override: time_interp_external_bridge should only be called to bridge with previous file')
            ! bridge with previous file
            call time_interp_external_bridge(id_time_prev,id_time,time,return_data(:,:,1),verbose=debug_data_override, &
                                      is_in=is_in,ie_in=ie_in,js_in=js_in,je_in=je_in,window_id=window_id)
          elseif (time>last_record) then
            ! next file must be init and time must be between last record of current file and
            ! first record of next file
            if (id_time_next<0) call mpp_error(fatal,'data_override:next file needed with multifile')
            if (time>data_table(index1)%time_next_records(1)) call mpp_error(fatal, &
                'data_override: time_interp_external_bridge should only be called to bridge with next file')
            ! bridge with next file
            call time_interp_external_bridge(id_time,id_time_next,time,return_data(:,:,1),verbose=debug_data_override, &
                                      is_in=is_in,ie_in=ie_in,js_in=js_in,je_in=je_in,window_id=window_id)
          else  ! first_record <= time <= last_record, do not use bridge
            call time_interp_external(id_time,time,return_data(:,:,1),verbose=debug_data_override, &
                                      is_in=is_in,ie_in=ie_in,js_in=js_in,je_in=je_in,window_id=window_id)
          endif if_time6
        else  ! standard behavior
          call time_interp_external(id_time,time,return_data(:,:,1),verbose=debug_data_override, &
                                    is_in=is_in,ie_in=ie_in,js_in=js_in,je_in=je_in,window_id=window_id)
        endif if_multi6
 
      else
        !> If this in an ongrid case and you are not in the compute domain, send in `data` to be the correct
        !! size
 
        ! if using consecutive files, allow to perform time interpolation between the last record of previous
        ! file and first record of current file OR between the last record of current file and first record of
        ! next file hence "bridging" over files.
        if_multi7: if (multifile) then
          if_time7: if (time<first_record) then
            ! previous file must be init and time must be between last record of previous file and
            ! first record of current file
            if (id_time_prev<0) call mpp_error(fatal,'data_override:previous file needed with multifile')
            prev_dims = get_external_field_size(id_time_prev)
            if (time<data_table(index1)%time_prev_records(prev_dims(4))) call mpp_error(fatal, &
                'data_override: time_interp_external_bridge should only be called to bridge with previous file')
            ! bridge with previous file
            call time_interp_external_bridge(id_time_prev,id_time,time,&
                                             return_data(startingi:endingi,startingj:endingj,1), &
                                             verbose=debug_data_override,is_in=is_in,ie_in=ie_in, &
                                             js_in=js_in,je_in=je_in,window_id=window_id)
          elseif (time>last_record) then
            ! next file must be init and time must be between last record of current file and
            ! first record of next file
            if (id_time_next<0) call mpp_error(fatal,'data_override:next file needed with multifile')
            if (time>data_table(index1)%time_next_records(1)) call mpp_error(fatal, &
                'data_override: time_interp_external_bridge should only be called to bridge with next file')
            ! bridge with next file
            call time_interp_external_bridge(id_time,id_time_next,time,&
                                             return_data(startingi:endingi,startingj:endingj,1), &
                                             verbose=debug_data_override,is_in=is_in,ie_in=ie_in, &
                                             js_in=js_in,je_in=je_in,window_id=window_id)
          else  ! first_record <= time <= last_record, do not use bridge
            call time_interp_external(id_time,time,return_data(startingi:endingi,startingj:endingj,1), &
                                      verbose=debug_data_override,is_in=is_in,ie_in=ie_in, &
                                      js_in=js_in,je_in=je_in,window_id=window_id)
          endif if_time7
        else  ! standard behavior
          call time_interp_external(id_time,time,return_data(startingi:endingi,startingj:endingj,1), &
                                    verbose=debug_data_override,is_in=is_in,ie_in=ie_in, &
                                    js_in=js_in,je_in=je_in,window_id=window_id)
        endif if_multi7
 
      end if
      return_data(:,:,1) = return_data(:,:,1)*factor
      do i = 2, size(return_data,3)
        return_data(:,:,i) = return_data(:,:,1)
      end do
    else
      if (use_comp_domain) then
 
        ! if using consecutive files, allow to perform time interpolation between the last record of previous
        ! file and first record of current file OR between the last record of current file and first record of
        ! next file hence "bridging" over files.
        if_multi8: if (multifile) then
          if_time8: if (time<first_record) then
            if (id_time_prev<0) call mpp_error(fatal,'data_override:previous file needed with multifile')
            prev_dims = get_external_field_size(id_time_prev)
            if (time<data_table(index1)%time_prev_records(prev_dims(4))) call mpp_error(fatal, &
                'data_override: time_interp_external_bridge should only be called to bridge with previous file')
            call time_interp_external_bridge(id_time_prev,id_time,time,return_data,verbose=debug_data_override, &
                                             is_in=is_in,ie_in=ie_in,js_in=js_in,je_in=je_in,window_id=window_id)
          elseif (time>last_record) then
            if (id_time_next<0) call mpp_error(fatal,'data_override:next file needed with multifile')
            if (time>data_table(index1)%time_next_records(1)) call mpp_error(fatal, &
                'data_override: time_interp_external_bridge should only be called to bridge with next file')
            call time_interp_external_bridge(id_time,id_time_next,time,return_data,verbose=debug_data_override, &
                                             is_in=is_in,ie_in=ie_in,js_in=js_in,je_in=je_in,window_id=window_id)
          else ! first_record <= time <= last_record, do not use bridge
            call time_interp_external(id_time,time,return_data,verbose=debug_data_override, &
                                      is_in=is_in,ie_in=ie_in,js_in=js_in,je_in=je_in,window_id=window_id)
          endif if_time8
        else ! standard behavior
          call time_interp_external(id_time,time,return_data,verbose=debug_data_override, &
                                    is_in=is_in,ie_in=ie_in,js_in=js_in,je_in=je_in,window_id=window_id)
       endif if_multi8
 
      else
        !> If this in an ongrid case and you are not in the compute domain, send in `data` to be the correct
        !! size
 
        ! if using consecutive files, allow to perform time interpolation between the last record of previous
        ! file and first record of current file OR between the last record of current file and first record of
        ! next file hence "bridging" over files.
        if_multi9: if (multifile) then
          if_time9: if (time<first_record) then
            if (id_time_prev<0) call mpp_error(fatal,'data_override:previous file needed with multifile')
            prev_dims = get_external_field_size(id_time_prev)
            if (time<data_table(index1)%time_prev_records(prev_dims(4))) call mpp_error(fatal, &
                'data_override: time_interp_external_bridge should only be called to bridge with previous file')
            call time_interp_external_bridge(id_time_prev,id_time,time,&
                                             return_data(startingi:endingi,startingj:endingj,:), &
                                             verbose=debug_data_override,is_in=is_in,ie_in=ie_in, &
                                             js_in=js_in,je_in=je_in,window_id=window_id)
          elseif (time>last_record) then
            if (id_time_next<0) call mpp_error(fatal,'data_override:next file needed with multifile')
            if (time>data_table(index1)%time_next_records(1)) call mpp_error(fatal, &
                'data_override: time_interp_external_bridge should only be called to bridge with next file')
            call time_interp_external_bridge(id_time,id_time_next,time,&
                                             return_data(startingi:endingi,startingj:endingj,:), &
                                             verbose=debug_data_override,is_in=is_in,ie_in=ie_in, &
                                             js_in=js_in,je_in=je_in,window_id=window_id)
          else ! first_record <= time <= last_record, do not use bridge
            call time_interp_external(id_time,time,return_data(startingi:endingi,startingj:endingj,:), &
                                      verbose=debug_data_override,is_in=is_in,ie_in=ie_in, &
                                      js_in=js_in,je_in=je_in,window_id=window_id)
          endif if_time9
        else ! standard behavior
          call time_interp_external(id_time,time,return_data(startingi:endingi,startingj:endingj,:), &
                                    verbose=debug_data_override,is_in=is_in,ie_in=ie_in, &
                                    js_in=js_in,je_in=je_in,window_id=window_id)
        endif if_multi9
 
      end if
      return_data = return_data*factor
    endif
  else  ! off grid case
! do time interp to get global data
     if(data_file_is_2d) then
        if( data_table(index1)%region_type == no_region ) then
 
           ! if using consecutive files, allow to perform time interpolation between the last record of previous
           ! file and first record of current file OR between the last record of current file and first record of
           ! next file hence "bridging" over files.
           if_multi10: if (multifile) then
             if_time10: if (time<first_record) then
               if (id_time_prev<0) call mpp_error(fatal,'data_override:previous file needed with multifile')
               prev_dims = get_external_field_size(id_time_prev)
               if (time<data_table(index1)%time_prev_records(prev_dims(4))) call mpp_error(fatal, &
                   'data_override: time_interp_external_bridge should only be called to bridge with previous file')
               call time_interp_external_bridge(id_time_prev,id_time,time,return_data(:,:,1), &
                                                verbose=debug_data_override, &
                                                horz_interp=override_array(curr_position)%horz_interp(window_id), &
                                                is_in=is_in,ie_in=ie_in,js_in=js_in,je_in=je_in,window_id=window_id)
             elseif (time>last_record) then
               if (id_time_next<0) call mpp_error(fatal,'data_override:next file needed with multifile')
               if (time>data_table(index1)%time_next_records(1)) call mpp_error(fatal, &
                   'data_override: time_interp_external_bridge should only be called to bridge with next file')
               call time_interp_external_bridge(id_time,id_time_next,time,return_data(:,:,1), &
                                                verbose=debug_data_override, &
                                                horz_interp=override_array(curr_position)%horz_interp(window_id), &
                                                is_in=is_in,ie_in=ie_in,js_in=js_in,je_in=je_in,window_id=window_id)
             else ! first_record <= time <= last_record, do not use bridge
               call time_interp_external(id_time,time,return_data(:,:,1),verbose=debug_data_override, &
                                         horz_interp=override_array(curr_position)%horz_interp(window_id), &
                                         is_in=is_in,ie_in=ie_in,js_in=js_in,je_in=je_in,window_id=window_id)
             endif if_time10
           else ! standard behavior
             call time_interp_external(id_time,time,return_data(:,:,1),verbose=debug_data_override, &
                                       horz_interp=override_array(curr_position)%horz_interp(window_id), &
                                       is_in=is_in,ie_in=ie_in,js_in=js_in,je_in=je_in,window_id=window_id)
           endif if_multi10
 
           return_data(:,:,1) = return_data(:,:,1)*factor
           do i = 2, size(return_data,3)
             return_data(:,:,i) = return_data(:,:,1)
           enddo
        else
           allocate(mask_out(size(return_data,1), size(return_data,2),1))
           mask_out = .false.
 
           ! if using consecutive files, allow to perform time interpolation between the last record of previous
           ! file and first record of current file OR between the last record of current file and first record of
           ! next file hence "bridging" over files.
           if_multi11: if (multifile) then
             if_time11: if (time<first_record) then
               if (id_time_prev<0) call mpp_error(fatal,'data_override:previous file needed with multifile')
               prev_dims = get_external_field_size(id_time_prev)
               if (time<data_table(index1)%time_prev_records(prev_dims(4))) call mpp_error(fatal, &
                   'data_override: time_interp_external_bridge should only be called to bridge with previous file')
               call time_interp_external_bridge(id_time_prev,id_time,time,return_data(:,:,1), &
                                                verbose=debug_data_override, &
                                                horz_interp=override_array(curr_position)%horz_interp(window_id), &
                                                mask_out   =mask_out(:,:,1), &
                                                is_in=is_in,ie_in=ie_in,js_in=js_in,je_in=je_in,window_id=window_id)
             elseif (time>last_record) then
               if (id_time_next<0) call mpp_error(fatal,'data_override:next file needed with multifile')
               if (time>data_table(index1)%time_next_records(1)) call mpp_error(fatal, &
                   'data_override: time_interp_external_bridge should only be called to bridge with next file')
               call time_interp_external_bridge(id_time,id_time_next,time,return_data(:,:,1), &
                                                verbose=debug_data_override, &
                                                horz_interp=override_array(curr_position)%horz_interp(window_id), &
                                                mask_out   =mask_out(:,:,1), &
                                                is_in=is_in,ie_in=ie_in,js_in=js_in,je_in=je_in,window_id=window_id)
             else ! first_record <= time <= last_record, do not use bridge
               call time_interp_external(id_time,time,return_data(:,:,1),verbose=debug_data_override, &
                                         horz_interp=override_array(curr_position)%horz_interp(window_id), &
                                         mask_out   =mask_out(:,:,1), &
                                         is_in=is_in,ie_in=ie_in,js_in=js_in,je_in=je_in,window_id=window_id)
             endif if_time11
           else ! standard behavior
             call time_interp_external(id_time,time,return_data(:,:,1),verbose=debug_data_override, &
                                       horz_interp=override_array(curr_position)%horz_interp(window_id), &
                                       mask_out   =mask_out(:,:,1), &
                                       is_in=is_in,ie_in=ie_in,js_in=js_in,je_in=je_in,window_id=window_id)
           endif if_multi11
 
           where(mask_out(:,:,1))
              return_data(:,:,1) = return_data(:,:,1)*factor
           end where
           do i = 2, size(return_data,3)
              where(mask_out(:,:,1))
              return_data(:,:,i) = return_data(:,:,1)
              end where
           enddo
           deallocate(mask_out)
        endif
     else
        if( data_table(index1)%region_type == no_region ) then
 
           ! if using consecutive files, allow to perform time interpolation between the last record of previous
           ! file and first record of current file OR between the last record of current file and first record of
           ! next file hence "bridging" over files.
           if_multi12: if (multifile) then
             if_time12: if (time<first_record) then
               if (id_time_prev<0) call mpp_error(fatal,'data_override:previous file needed with multifile')
               prev_dims = get_external_field_size(id_time_prev)
               if (time<data_table(index1)%time_prev_records(prev_dims(4))) call mpp_error(fatal, &
                   'data_override: time_interp_external_bridge should only be called to bridge with previous file')
               call time_interp_external_bridge(id_time_prev,id_time,time,return_data,verbose=debug_data_override, &
                                                horz_interp=override_array(curr_position)%horz_interp(window_id), &
                                                is_in=is_in,ie_in=ie_in,js_in=js_in,je_in=je_in,window_id=window_id)
             elseif (time>last_record) then
               if (id_time_next<0) call mpp_error(fatal,'data_override:next file needed with multifile')
               if (time>data_table(index1)%time_next_records(1)) call mpp_error(fatal, &
                   'data_override: time_interp_external_bridge should only be called to bridge with next file')
               call time_interp_external_bridge(id_time,id_time_next,time,return_data,verbose=debug_data_override, &
                                                horz_interp=override_array(curr_position)%horz_interp(window_id), &
                                                is_in=is_in,ie_in=ie_in,js_in=js_in,je_in=je_in,window_id=window_id)
             else ! first_record <= time <= last_record, do not use bridge
               call time_interp_external(id_time,time,return_data,verbose=debug_data_override, &
                    horz_interp=override_array(curr_position)%horz_interp(window_id), &
                    is_in=is_in,ie_in=ie_in,js_in=js_in,je_in=je_in,window_id=window_id)
             endif if_time12
           else ! standard behavior
             call time_interp_external(id_time,time,return_data,verbose=debug_data_override, &
                  horz_interp=override_array(curr_position)%horz_interp(window_id), &
                  is_in=is_in,ie_in=ie_in,js_in=js_in,je_in=je_in,window_id=window_id)
           endif if_multi12
 
           return_data = return_data*factor
        else
           allocate(mask_out(size(return_data,1), size(return_data,2), size(return_data,3)) )
           mask_out = .false.
 
           ! if using consecutive files, allow to perform time interpolation between the last record of previous
           ! file and first record of current file OR between the last record of current file and first record of
           ! next file hence "bridging" over files.
           if_multi13: if (multifile) then
             if_time13: if (time<first_record) then
               if (id_time_prev<0) call mpp_error(fatal,'data_override:previous file needed with multifile')
               prev_dims = get_external_field_size(id_time_prev)
               if (time<data_table(index1)%time_prev_records(prev_dims(4))) call mpp_error(fatal, &
                   'data_override: time_interp_external_bridge should only be called to bridge with previous file')
               call time_interp_external_bridge(id_time_prev,id_time,time,return_data,verbose=debug_data_override, &
                                                horz_interp=override_array(curr_position)%horz_interp(window_id), &
                                                mask_out   =mask_out, &
                                                is_in=is_in,ie_in=ie_in,js_in=js_in,je_in=je_in,window_id=window_id)
             elseif (time>last_record) then
               if (id_time_next<0) call mpp_error(fatal,'data_override:next file needed with multifile')
               if (time>data_table(index1)%time_next_records(1)) call mpp_error(fatal, &
                   'data_override: time_interp_external_bridge should only be called to bridge with next file')
               call time_interp_external_bridge(id_time,id_time_next,time,return_data,verbose=debug_data_override, &
                                                horz_interp=override_array(curr_position)%horz_interp(window_id), &
                                                mask_out   =mask_out, &
                                                is_in=is_in,ie_in=ie_in,js_in=js_in,je_in=je_in,window_id=window_id)
             else ! first_record <= time <= last_record, do not use bridge
               call time_interp_external(id_time,time,return_data,verbose=debug_data_override, &
                    horz_interp=override_array(curr_position)%horz_interp(window_id), &
                    mask_out   =mask_out, &
                    is_in=is_in,ie_in=ie_in,js_in=js_in,je_in=je_in,window_id=window_id)
             endif if_time13
           else ! standard behavior
             call time_interp_external(id_time,time,return_data,verbose=debug_data_override, &
                  horz_interp=override_array(curr_position)%horz_interp(window_id), &
                  mask_out   =mask_out, &
                  is_in=is_in,ie_in=ie_in,js_in=js_in,je_in=je_in,window_id=window_id)
           endif if_multi13
 
           where(mask_out)
           return_data = return_data*factor
           end where
           deallocate(mask_out)
        endif
     endif
 
  endif
 
  if(PRESENT(override)) override = .true.
end subroutine data_override_3d_
 
!> @brief Data override for 1D unstructured grids
subroutine data_override_ug_1d_(gridname,fieldname,return_data,time,override)
  character(len=3),   intent(in) :: gridname !< model grid ID
  character(len=*),   intent(in) :: fieldname !< field to override
  real(FMS_DATA_OVERRIDE_KIND_), dimension(:), intent(inout) :: return_data !< data returned by this call
  type(time_type),    intent(in) :: time !<  model time
  logical, intent(out), optional :: override !< true if the field has been overriden succesfully
  !local vars
  real(FMS_DATA_OVERRIDE_KIND_), dimension(:,:), allocatable ::  data_SG
  type(domainUG) :: UG_domain
  integer       :: index1
  integer       :: i
  integer, dimension(4) :: comp_domain = 0  !< istart,iend,jstart,jend for compute domain
 
  !1  Look  for the data file in data_table
  if(PRESENT(override)) override = .false.
  index1 = -1
  do i = 1, table_size
     if( trim(gridname) /= trim(data_table(i)%gridname)) cycle
     if( trim(fieldname) /= trim(data_table(i)%fieldname_code)) cycle
     index1 = i                               ! field found
     exit
  enddo
  if(index1 .eq. -1) return  ! NO override was performed
 
  call get_domainug(gridname,ug_domain,comp_domain)
  allocate(data_sg(comp_domain(1):comp_domain(2),comp_domain(3):comp_domain(4)))
 
  call data_override_2d_(gridname,fieldname,data_sg,time,override)
 
  call mpp_pass_sg_to_ug(ug_domain, data_sg(:,:), return_data(:))
 
  deallocate(data_sg)
end subroutine data_override_ug_1d_
 
!> @brief Data override for 2D unstructured grids
subroutine data_override_ug_2d_(gridname,fieldname,return_data,time,override)
  character(len=3),     intent(in) :: gridname !< model grid ID
  character(len=*),     intent(in) :: fieldname !< field to override
  real(FMS_DATA_OVERRIDE_KIND_), dimension(:,:), intent(inout) :: return_data !< data returned by this call
  type(time_type),      intent(in) :: time !<  model time
  logical, intent(out), optional :: override !< true if the field has been overriden succesfully
  !local vars
  real(FMS_DATA_OVERRIDE_KIND_), dimension(:,:,:), allocatable ::  data_SG
  real(FMS_DATA_OVERRIDE_KIND_), dimension(:,:),   allocatable ::  data_UG
  type(domainUG) :: UG_domain
  integer       :: index1
  integer       :: i, nlevel, nlevel_max
  integer, dimension(4) :: comp_domain = 0  !< istart,iend,jstart,jend for compute domain
 
!1  Look  for the data file in data_table
  if(PRESENT(override)) override = .false.
  index1 = -1
  do i = 1, table_size
     if( trim(gridname) /= trim(data_table(i)%gridname)) cycle
     if( trim(fieldname) /= trim(data_table(i)%fieldname_code)) cycle
     index1 = i                               ! field found
     exit
  enddo
  if(index1 .eq. -1) return  ! NO override was performed
 
  nlevel = size(return_data,2)
  nlevel_max = nlevel
  call mpp_max(nlevel_max)
 
  call get_domainug(gridname,ug_domain,comp_domain)
  allocate(data_sg(comp_domain(1):comp_domain(2),comp_domain(3):comp_domain(4),nlevel_max))
  allocate(data_ug(size(return_data,1), nlevel_max))
  data_sg = 0._lkind
  call data_override_3d_(gridname,fieldname,data_sg,time,override)
 
  call mpp_pass_sg_to_ug(ug_domain, data_sg(:,:,:), data_ug(:,:))
  return_data(:,1:nlevel) = data_ug(:,1:nlevel)
 
  deallocate(data_sg, data_ug)
end subroutine data_override_ug_2d_