Detailed Description

Surface forcing for the boundary-forced-basin (BFB) configuration.

Data Types
type	bfb_surface_forcing_cs
	Control structure for BFB_surface_forcing. More...

Functions/Subroutines
subroutine, public	bfb_buoyancy_forcing (sfc_state, fluxes, day, dt, G, US, CS)
	Bouyancy forcing for the boundary-forced-basin (BFB) configuration. More...

subroutine, public	bfb_surface_forcing_init (Time, G, US, param_file, diag, CS)
	Initialization for forcing the boundary-forced-basin (BFB) configuration. More...

Function/Subroutine Documentation

◆ bfb_buoyancy_forcing()

subroutine, public bfb_surface_forcing::bfb_buoyancy_forcing	(	type(surface), intent(inout)	sfc_state,
		type(forcing), intent(inout)	fluxes,
		type(time_type), intent(in)	day,
		real, intent(in)	dt,
		type(ocean_grid_type), intent(in)	G,
		type(unit_scale_type), intent(in)	US,
		type(bfb_surface_forcing_cs), pointer	CS
	)

Bouyancy forcing for the boundary-forced-basin (BFB) configuration.

Parameters

[in,out]	sfc_state	A structure containing fields that describe the surface state of the ocean.
[in,out]	fluxes	A structure containing pointers to any possible forcing fields. Unused fields have NULL ptrs.
[in]	day	Time of the fluxes.
[in]	dt	The amount of time over which the fluxes apply [s]
[in]	g	The ocean's grid structure
[in]	us	A dimensional unit scaling type
	cs	A pointer to the control structure returned by a previous call to BFB_surface_forcing_init.

Definition at line 51 of file BFB_surface_forcing.F90.

   type(surface),                intent(inout) :: sfc_state  !< A structure containing fields that
                                                       !! describe the surface state of the ocean.
   type(forcing),                intent(inout) :: fluxes !< A structure containing pointers to any
                                                       !! possible forcing fields. Unused fields
                                                       !! have NULL ptrs.
   type(time_type),              intent(in)    :: day  !< Time of the fluxes.
   real,                         intent(in)    :: dt   !< The amount of time over which
                                                       !! the fluxes apply [s]
   type(ocean_grid_type),        intent(in)    :: g    !< The ocean's grid structure
   type(unit_scale_type),        intent(in)    :: us   !< A dimensional unit scaling type
   type(bfb_surface_forcing_cs), pointer       :: cs   !< A pointer to the control structure
                                                       !! returned by a previous call to
                                                       !! BFB_surface_forcing_init.
   ! Local variables
   real :: temp_restore   ! The temperature that is being restored toward [degC].
   real :: salin_restore  ! The salinity that is being restored toward [ppt].
   real :: density_restore  ! The potential density that is being restored
                          ! toward [R ~> kg m-3].
   real :: rhoxcp           ! Reference density times heat capacity times unit scaling
                            ! factors [Q R degC-1 ~> J m-3 degC-1]
   real :: buoy_rest_const  ! A constant relating density anomalies to the
                            ! restoring buoyancy flux [L2 T-3 R-1 ~> m5 s-3 kg-1].
   integer :: i, j, is, ie, js, je
   integer :: isd, ied, jsd, jed
 
   is = g%isc ; ie = g%iec ; js = g%jsc ; je = g%jec
   isd = g%isd ; ied = g%ied ; jsd = g%jsd ; jed = g%jed
 
   ! Allocate and zero out the forcing arrays, as necessary.  This portion is
   ! usually not changed.
   if (cs%use_temperature) then
     call safe_alloc_ptr(fluxes%evap, isd, ied, jsd, jed)
     call safe_alloc_ptr(fluxes%lprec, isd, ied, jsd, jed)
     call safe_alloc_ptr(fluxes%fprec, isd, ied, jsd, jed)
     call safe_alloc_ptr(fluxes%lrunoff, isd, ied, jsd, jed)
     call safe_alloc_ptr(fluxes%frunoff, isd, ied, jsd, jed)
     call safe_alloc_ptr(fluxes%vprec, isd, ied, jsd, jed)
 
     call safe_alloc_ptr(fluxes%sw, isd, ied, jsd, jed)
     call safe_alloc_ptr(fluxes%lw, isd, ied, jsd, jed)
     call safe_alloc_ptr(fluxes%latent, isd, ied, jsd, jed)
     call safe_alloc_ptr(fluxes%sens, isd, ied, jsd, jed)
   else ! This is the buoyancy only mode.
     call safe_alloc_ptr(fluxes%buoy, isd, ied, jsd, jed)
   endif
 
   if ( cs%use_temperature ) then
     ! Set whichever fluxes are to be used here.  Any fluxes that
     ! are always zero do not need to be changed here.
     do j=js,je ; do i=is,ie
       ! Fluxes of fresh water through the surface are in units of [R Z T-1 ~> kg m-2 s-1]
       ! and are positive downward - i.e. evaporation should be negative.
       fluxes%evap(i,j) = -0.0 * g%mask2dT(i,j)
       fluxes%lprec(i,j) = 0.0 * g%mask2dT(i,j)
 
       ! vprec will be set later, if it is needed for salinity restoring.
       fluxes%vprec(i,j) = 0.0
 
       ! Heat fluxes are in units of [Q R Z T-1 ~> W m-2] and are positive into the ocean.
       fluxes%lw(i,j) = 0.0 * g%mask2dT(i,j)
       fluxes%latent(i,j) = 0.0 * g%mask2dT(i,j)
       fluxes%sens(i,j) = 0.0 * g%mask2dT(i,j)
       fluxes%sw(i,j) = 0.0 * g%mask2dT(i,j)
     enddo ; enddo
   else ! This is the buoyancy only mode.
     do j=js,je ; do i=is,ie
       !   fluxes%buoy is the buoyancy flux into the ocean [L2 T-3 ~> m2 s-3].  A positive
       ! buoyancy flux is of the same sign as heating the ocean.
       fluxes%buoy(i,j) = 0.0 * g%mask2dT(i,j)
     enddo ; enddo
   endif
 
   if (cs%restorebuoy) then
     if (cs%use_temperature) then
       call safe_alloc_ptr(fluxes%heat_added, isd, ied, jsd, jed)
       !   When modifying the code, comment out this error message.  It is here
       ! so that the original (unmodified) version is not accidentally used.
       call mom_error(fatal, "User_buoyancy_surface_forcing: " // &
         "Temperature and salinity restoring used without modification." )
 
       rhoxcp = cs%Rho0 * fluxes%C_p
       do j=js,je ; do i=is,ie
         !   Set Temp_restore and Salin_restore to the temperature (in degC) and
         ! salinity (in ppt) that are being restored toward.
         temp_restore = 0.0
         salin_restore = 0.0
 
         fluxes%heat_added(i,j) = (g%mask2dT(i,j) * (rhoxcp * cs%Flux_const)) * &
             (temp_restore - sfc_state%SST(i,j))
         fluxes%vprec(i,j) = - (g%mask2dT(i,j) * (cs%Rho0*cs%Flux_const)) * &
             ((salin_restore - sfc_state%SSS(i,j)) / (0.5 * (salin_restore + sfc_state%SSS(i,j))))
       enddo ; enddo
     else
       !   When modifying the code, comment out this error message.  It is here
       ! so that the original (unmodified) version is not accidentally used.
       ! call MOM_error(FATAL, "User_buoyancy_surface_forcing: " // &
       !   "Buoyancy restoring used without modification." )
 
       ! The -1 is because density has the opposite sign to buoyancy.
       buoy_rest_const = -1.0 * (cs%G_Earth * cs%Flux_const) / cs%Rho0
       temp_restore = 0.0
       do j=js,je ; do i=is,ie
        !   Set density_restore to an expression for the surface potential
        ! density [R ~> kg m-3] that is being restored toward.
         if (g%geoLatT(i,j) < cs%lfrslat) then
             temp_restore = cs%SST_s
         elseif (g%geoLatT(i,j) > cs%lfrnlat) then
             temp_restore = cs%SST_n
         else
             temp_restore = (cs%SST_s - cs%SST_n)/(cs%lfrslat - cs%lfrnlat) * &
                     (g%geoLatT(i,j) - cs%lfrslat) + cs%SST_s
         endif
 
         density_restore = temp_restore*cs%drho_dt + cs%Rho0
 
         fluxes%buoy(i,j) = g%mask2dT(i,j) * buoy_rest_const * &
                           (density_restore - sfc_state%sfc_density(i,j))
       enddo ; enddo
     endif
   endif                                             ! end RESTOREBUOY
 

◆ bfb_surface_forcing_init()

subroutine, public bfb_surface_forcing::bfb_surface_forcing_init	(	type(time_type), intent(in)	Time,
		type(ocean_grid_type), intent(in)	G,
		type(unit_scale_type), intent(in)	US,
		type(param_file_type), intent(in)	param_file,
		type(diag_ctrl), intent(in), target	diag,
		type(bfb_surface_forcing_cs), pointer	CS
	)

Initialization for forcing the boundary-forced-basin (BFB) configuration.

Parameters

[in]	time	The current model time.
[in]	g	The ocean's grid structure
[in]	us	A dimensional unit scaling type
[in]	param_file	A structure to parse for run-time parameters
[in]	diag	A structure that is used to regulate diagnostic output.
	cs	A pointer to the control structure for this module

Definition at line 176 of file BFB_surface_forcing.F90.

   type(time_type),              intent(in) :: time !< The current model time.
   type(ocean_grid_type),        intent(in) :: g    !< The ocean's grid structure
   type(unit_scale_type),        intent(in) :: us   !< A dimensional unit scaling type
   type(param_file_type),        intent(in) :: param_file !< A structure to parse for run-time parameters
   type(diag_ctrl), target,      intent(in) :: diag !< A structure that is used to
                                                    !! regulate diagnostic output.
   type(bfb_surface_forcing_cs), pointer    :: cs   !< A pointer to the control structure for this module
 ! This include declares and sets the variable "version".
 #include "version_variable.h"
   character(len=40)  :: mdl = "BFB_surface_forcing" ! This module's name.
 
   if (associated(cs)) then
     call mom_error(warning, "BFB_surface_forcing_init called with an associated "// &
                              "control structure.")
     return
   endif
   allocate(cs)
   cs%diag => diag
 
   ! Read all relevant parameters and write them to the model log.
   call log_version(param_file, mdl, version, "")
   call get_param(param_file, mdl, "ENABLE_THERMODYNAMICS", cs%use_temperature, &
                  "If true, Temperature and salinity are used as state variables.", default=.true.)
 
   call get_param(param_file, mdl, "G_EARTH", cs%G_Earth, &
                  "The gravitational acceleration of the Earth.", &
                  units="m s-2", default = 9.80, scale=us%m_to_L**2*us%Z_to_m*us%T_to_s**2)
   call get_param(param_file, mdl, "RHO_0", cs%Rho0, &
                  "The mean ocean density used with BOUSSINESQ true to "//&
                  "calculate accelerations and the mass for conservation "//&
                  "properties, or with BOUSSINSEQ false to convert some "//&
                  "parameters from vertical units of m to kg m-2.", &
                  units="kg m-3", default=1035.0, scale=us%kg_m3_to_R)
   call get_param(param_file, mdl, "LFR_SLAT", cs%lfrslat, &
                  "Southern latitude where the linear forcing ramp begins.", &
                  units="degrees", default=20.0)
   call get_param(param_file, mdl, "LFR_NLAT", cs%lfrnlat, &
                  "Northern latitude where the linear forcing ramp ends.", &
                  units="degrees", default=40.0)
   call get_param(param_file, mdl, "SST_S", cs%SST_s, &
                  "SST at the southern edge of the linear forcing ramp.", &
                  units="C", default=20.0)
   call get_param(param_file, mdl, "SST_N", cs%SST_n, &
                  "SST at the northern edge of the linear forcing ramp.", &
                  units="C", default=10.0)
   call get_param(param_file, mdl, "DRHO_DT", cs%drho_dt, &
                  "The rate of change of density with temperature.", &
                  units="kg m-3 K-1", default=-0.2, scale=us%kg_m3_to_R)
   call get_param(param_file, mdl, "GUST_CONST", cs%gust_const, &
                  "The background gustiness in the winds.", units="Pa", default=0.0)
 
   call get_param(param_file, mdl, "RESTOREBUOY", cs%restorebuoy, &
                  "If true, the buoyancy fluxes drive the model back "//&
                  "toward some specified surface state with a rate "//&
                  "given by FLUXCONST.", default= .false.)
   if (cs%restorebuoy) then
     call get_param(param_file, mdl, "FLUXCONST", cs%Flux_const, &
                  "The constant that relates the restoring surface fluxes to the relative "//&
                  "surface anomalies (akin to a piston velocity).  Note the non-MKS units.", &
                  default=0.0, units="m day-1", scale=us%m_to_Z*us%T_to_s)
     ! Convert CS%Flux_const from m day-1 to m s-1.
     cs%Flux_const = cs%Flux_const / 86400.0
   endif
 

Detailed Description

Data Types

Functions/Subroutines

Function/Subroutine Documentation

◆ bfb_buoyancy_forcing()

◆ bfb_surface_forcing_init()