subroutine ConstantsSnowSeaIceInit
    !
    ! constants_snowseaice モジュールの初期化を行います. 
    ! NAMELIST#constants_snowseaice_nml の読み込みはこの手続きで行われます. 
    !
    ! "constants_snowseaice" module is initialized. 
    ! NAMELIST#constants_snowseaice_nml is loaded in this procedure. 
    !

    ! モジュール引用 ; USE statements
    !

    ! NAMELIST ファイル入力に関するユーティリティ
    ! Utilities for NAMELIST file input
    !
    use namelist_util, only: namelist_filename, NmlutilMsg

    ! ファイル入出力補助
    ! File I/O support
    !
    use dc_iounit, only: FileOpen

    ! 種別型パラメタ
    ! Kind type parameter
    !
    use dc_types, only: STDOUT ! 標準出力の装置番号. Unit number of standard output

    ! メッセージ出力
    ! Message output
    !
    use dc_message, only: MessageNotify

    ! 宣言文 ; Declaration statements
    !
    implicit none

    integer:: unit_nml        ! NAMELIST ファイルオープン用装置番号. 
                              ! Unit number for NAMELIST file open
    integer:: iostat_nml      ! NAMELIST 読み込み時の IOSTAT. 
                              ! IOSTAT of NAMELIST read

    ! NAMELIST 変数群
    ! NAMELIST group name
    !
    namelist /constants_snowseaice_nml/ ThresholdSurfSnow  , SnowAlbedo         , TempCondWater      , SeaIceVolHeatCap   , SeaIceThermCondCoef, SeaIceThreshold    , SeaIceThickness    , TempBelowSeaIce    , SeaIceAlbedo

          !
          ! デフォルト値については初期化手続 "constants#ConstantsInit" 
          ! のソースコードを参照のこと. 
          !
          ! Refer to source codes in the initialization procedure
          ! "constants#ConstantsInit" for the default values. 
          !

    ! 実行文 ; Executable statement
    !

    if ( constants_snowseaice_inited ) return
    call InitCheck

    ! デフォルト値の設定
    ! Default values settings
    !

    ThresholdSurfSnow  = 0.1d0 * 1.0d3 * 0.01d0
                        ! 1 cm snow depth
                        ! 0.1 * 1000 (kg m-3; water density) x 1 cm
                        ! This value is selected arbitrarily. 
    SnowAlbedo         = 0.7d0
                        ! This value is selected arbitrarily. 
    TempCondWater      = 273.15d0
                        ! <Japanese>
                        ! Condensation temperature of water

!!$    ! https://www.myroms.org/wiki/index.php/Sea-Ice_Model
!!$    SeaIceDens         = 900.0d0   ! no reliable reference
!!$    SeaIceSpecHeat     = 2093.0d0  ! no reliable reference
!!$    SeaIceHeatDiffCoef = 2.04d0 / ( SeaIceDens * SeaIceSpecHeat )  ! 2.04d0 (W (m K)-1),  no reliable reference

!!$    SeaIceDens         = 0.92d3
!!$    ! kg m-3
!!$    SeaIceHeatDiffCoef = 2.04d0 / ( SeaIceDens * SeaIceSpecHeat )
!!$    ! 2.04d0 (W (m K)-1),  no reliable reference
!!$    SeaIceSpecHeat     = 1.9d6 / SeaIceDens
!!$    ! no reliable reference

    SeaIceVolHeatCap    = 1.9d6
    ! J m-3 K-1
    ! Value of ice in Table 12.1 by Hillel (2004). 
    SeaIceThermCondCoef = 2.2d0
    ! W m-1 K-1
    ! Value of ice in Table 12.2 by Hillel (2004). 

    ! Reference
    !
    ! Hillet, D., 
    !   Introduction to Environmental Soil Physics, 
    !   Elsevier Academic Press, pp494, 2004.


    SeaIceThreshold    = 0.5d0            ! arbitrarily set, no reliable reference
    SeaIceThickness    = 2.0d0            ! arbitrarily set, no reliable reference
    TempBelowSeaIce    = 273.15d0 - 2.0d0 ! arbitrarily set, no reliable reference

    SeaIceAlbedo       = 0.5d0            ! arbitrarily set, no reliable reference

    ! NAMELIST からの入力
    ! Input from NAMELIST
    !
    if ( trim(namelist_filename) /= '' ) then
      call FileOpen( unit_nml, namelist_filename, mode = 'r' ) ! (in)

      rewind( unit_nml )
      read( unit_nml, nml = constants_snowseaice_nml, iostat = iostat_nml            )   ! (out)
      close( unit_nml )

      call NmlutilMsg( iostat_nml, module_name ) ! (in)
      if ( iostat_nml == 0 ) write( STDOUT, nml = constants_snowseaice_nml )
    end if

    ! 印字 ; Print
    !
    call MessageNotify( 'M', module_name, '----- Initialization Messages -----' )
    call MessageNotify( 'M', module_name, '  ThresholdSurfSnow   = %f', d = (/ ThresholdSurfSnow   /) )
    call MessageNotify( 'M', module_name, '  SnowAlbedo          = %f', d = (/ SnowAlbedo          /) )
    call MessageNotify( 'M', module_name, '  TempCondWater       = %f', d = (/ TempCondWater       /) )
    call MessageNotify( 'M', module_name, '  SeaIceThreshold     = %f', d = (/ SeaIceThreshold     /) )
    call MessageNotify( 'M', module_name, '  SeaIceVolHeatCap    = %f', d = (/ SeaIceVolHeatCap    /) )
    call MessageNotify( 'M', module_name, '  SeaIceThermCondCoef = %f', d = (/ SeaIceThermCondCoef /) )

!!$    call MessageNotify( 'M', module_name, '  SeaIceDens         = %f', d = (/ SeaIceDens         /) )
!!$    call MessageNotify( 'M', module_name, '  SeaIceSpecHeat     = %f', d = (/ SeaIceSpecHeat     /) )
!!$    call MessageNotify( 'M', module_name, '  SeaIceHeatDiffCoef = %f', d = (/ SeaIceHeatDiffCoef /) )

    call MessageNotify( 'M', module_name, '  SeaIceThickness     = %f', d = (/ SeaIceThickness     /) )
    call MessageNotify( 'M', module_name, '  TempBelowSeaIce     = %f', d = (/ TempBelowSeaIce     /) )
    call MessageNotify( 'M', module_name, '  SeaIceAlbedo        = %f', d = (/ SeaIceAlbedo        /) )
    call MessageNotify( 'M', module_name, '-- version = %c', c1 = trim(version) )

    constants_snowseaice_inited = .true.
  end subroutine ConstantsSnowSeaIceInit

  subroutine InitCheck
    !
    ! 依存モジュールの初期化チェック
    !
    ! Check initialization of dependency modules

    ! モジュール引用 ; USE statements
    !

    ! NAMELIST ファイル入力に関するユーティリティ
    ! Utilities for NAMELIST file input
    !
    use namelist_util, only: namelist_util_inited

    ! メッセージ出力
    ! Message output
    !
    use dc_message, only: MessageNotify

    ! 実行文 ; Executable statement
    !

    if ( .not. namelist_util_inited ) call MessageNotify( 'E', module_name, '"namelist_util" module is not initialized.' )

  end subroutine InitCheck