barotropic_state_t Derived Type

type, public :: barotropic_state_t

Depth-integrated state on an Arakawa C-grid (face-located velocities as continuity-PPM produces/consumes; cell-centred h-update by flux div).


Inherited by

type~~barotropic_state_t~~InheritedByGraph type~barotropic_state_t barotropic_state_t type~ocean_state_t ocean_state_t type~ocean_state_t->type~barotropic_state_t barotropic type~ocean_engine_t ocean_engine_t type~ocean_engine_t->type~ocean_state_t state type~ocean_handle_t ocean_handle_t type~ocean_handle_t->type~ocean_state_t state type~ocean_handle_t->type~ocean_engine_t engine

Components

Type Visibility Attributes Name Initial
real(kind=wp), public, allocatable :: b(:,:)

Reference column DEPTH at cell centre (m, positive down): a 4000 m deep cell holds b = +4000, land holds b = 0, and a cell is land iff b < LAND_DEPTH_THRESHOLD (2 m, rdb_constants). Fixed by the SSH identity eta = sum_k h_layer - b (rdb_ocean_diag_fills.F90:157) and by barotropic%h = b + eta (rdb_ocean_state.F90:2482).

NOTE the opposite sign of the topographic HEIGHTS used by the porous-barrier statistics (rdb_ocean_porous.F90:17-21) and by metrics%bed_height (rdb_ocean_metrics.F90:151, = -b), and of GEBCO/ETOPO products, which give a negative height. Handing a negative-height array in unflipped puts every cell below the land threshold and yields a silent, crash-free, all-land run. (This docstring previously read “positive up” — a coastal-path leftover; the coastal regime left this tree in the ocean-only split.)
real(kind=wp), public :: coriolis_f = 0.0_wp

Beta-plane / f-plane Coriolis parameter (1/s).
real(kind=wp), public, allocatable :: flux_h(:,:)
real(kind=wp), public, allocatable :: h(:,:)

Water depth at cell centre (m), shape (nx_total, ny_total)
real(kind=wp), public, allocatable :: h0(:,:)
real(kind=wp), public, allocatable :: hu_face_x(:,:)

Face-thickness x momentum h*u (m^2/s)
real(kind=wp), public, allocatable :: hv_face_y(:,:)

Face-thickness y momentum h*v (m^2/s)
logical, public :: is_init = .false.

True between init and destroy. Prefer to allocated(...) — it also tracks GPU device attachment, which allocated cannot see.
real(kind=wp), public :: manning_n = 0.0_wp

Manning roughness for shelf-side bottom drag.
real(kind=wp), public, allocatable :: mass_flux_x(:,:)
real(kind=wp), public, allocatable :: mass_flux_y(:,:)
real(kind=wp), public, allocatable :: u_face_x(:,:)

x-velocity at east face of each cell (m/s)
real(kind=wp), public, allocatable :: u_face_x0(:,:)
real(kind=wp), public, allocatable :: v_face_y(:,:)

y-velocity at north face of each cell (m/s)
real(kind=wp), public, allocatable :: v_face_y0(:,:)

Type-Bound Procedures

procedure, public, non_overridable :: bytes => barotropic_state_bytes

  • private pure function barotropic_state_bytes(this) result(nbytes)

    Counted allocatable footprint of the ocean C-grid barotropic slot.

    Arguments

    Type IntentOptional Attributes Name
    class(barotropic_state_t), intent(in) :: this

    Return Value integer(kind=int64)

procedure, public, non_overridable :: destroy => barotropic_state_destroy

  • private subroutine barotropic_state_destroy(this)

    Tear down host allocations. Call exit_data first — destroying a still-device-mapped state leaks device memory silently.

    Arguments

    Type IntentOptional Attributes Name
    class(barotropic_state_t), intent(inout) :: this

procedure, public, non_overridable :: enter_data => barotropic_state_enter_data

  • private subroutine barotropic_state_enter_data(this)

    Attach the C-grid barotropic allocatables to the device. The parent struct is mapped by the orchestrating routine. Read+write fields use copyin; pure-workspace fields use create.

    Arguments

    Type IntentOptional Attributes Name
    class(barotropic_state_t), intent(inout) :: this

procedure, public, non_overridable :: exit_data => barotropic_state_exit_data

  • private subroutine barotropic_state_exit_data(this)

    Reverse of enter_data — copy out prognostic fields, drop scratch. Caller detaches the parent struct after this returns.

    Arguments

    Type IntentOptional Attributes Name
    class(barotropic_state_t), intent(inout) :: this

procedure, public, non_overridable :: init => barotropic_state_init

  • private subroutine barotropic_state_init(this, grid)

    Allocate every C-grid barotropic array zero-filled. East-face arrays are (nx+1, ny), north-face (nx, ny+1). Scalars (manning_n, coriolis_f) are populated by state_init_from_config afterwards.

    Arguments

    Type IntentOptional Attributes Name
    class(barotropic_state_t), intent(inout) :: this
    type(hgrid_t), intent(in) :: grid

Source Code

   type :: barotropic_state_t
      !! Depth-integrated state on an Arakawa C-grid (face-located velocities as
      !! continuity-PPM produces/consumes; cell-centred h-update by flux div).

      logical :: is_init = .false.
         !! True between `init` and `destroy`. Prefer to `allocated(...)` — it
         !! also tracks GPU device attachment, which `allocated` cannot see.

      ! ---- Cell-centred scalars ----
      real(wp), allocatable :: h(:, :)
         !! Water depth at cell centre (m), shape (nx_total, ny_total)
      real(wp), allocatable :: b(:, :)
         !! Reference column DEPTH at cell centre (m, **positive down**):
         !! a 4000 m deep cell holds `b = +4000`, land holds `b = 0`, and a
         !! cell is land iff `b < LAND_DEPTH_THRESHOLD` (2 m,
         !! `rdb_constants`).  Fixed by the SSH identity
         !! `eta = sum_k h_layer - b` (`rdb_ocean_diag_fills.F90:157`) and by
         !! `barotropic%h = b + eta` (`rdb_ocean_state.F90:2482`).
         !!
         !! NOTE the opposite sign of the topographic HEIGHTS used by the
         !! porous-barrier statistics (`rdb_ocean_porous.F90:17-21`) and by
         !! `metrics%bed_height` (`rdb_ocean_metrics.F90:151`, `= -b`), and of
         !! GEBCO/ETOPO products, which give a negative height.  Handing a
         !! negative-height array in unflipped puts every cell below the land
         !! threshold and yields a silent, crash-free, all-land run.
         !! (This docstring previously read "positive up" — a coastal-path
         !! leftover; the coastal regime left this tree in the ocean-only
         !! split.)

      ! ---- Face-located velocities / momentum ----
      ! u on east face: u_face_x(i,j) at interface (i,j)|(i+1,j), shape
      ! (nx_total+1, ny_total) so face index runs 1 (west wall)..nx+1 (east wall).
      real(wp), allocatable :: u_face_x(:, :)
         !! x-velocity at east face of each cell (m/s)
      real(wp), allocatable :: hu_face_x(:, :)
         !! Face-thickness x momentum h*u (m^2/s)

      ! v on north face: v_face_y(i,j) at interface (i,j)|(i,j+1),
      ! shape (nx_total, ny_total+1).
      real(wp), allocatable :: v_face_y(:, :)
         !! y-velocity at north face of each cell (m/s)
      real(wp), allocatable :: hv_face_y(:, :)
         !! Face-thickness y momentum h*v (m^2/s)

      ! ---- Per-face mass fluxes (continuity-PPM primary output) ----
      ! PPM mass flux at east/north faces; consumed by tracer advection under
      ! CWC. Same shape as the face-velocity arrays.
      real(wp), allocatable :: mass_flux_x(:, :)
      real(wp), allocatable :: mass_flux_y(:, :)

      ! ---- Flux divergence (workspace) ----
      ! Cell-centred net divergence used to step h forward.
      real(wp), allocatable :: flux_h(:, :)

      ! ---- RK2 save buffers ----
      ! State at start of the outer RK step; the inner substeps run N times
      ! from this snapshot.
      real(wp), allocatable :: h0(:, :)
      real(wp), allocatable :: u_face_x0(:, :)
      real(wp), allocatable :: v_face_y0(:, :)

      ! ---- Physics scalars ----
      real(wp) :: manning_n = 0.0_wp
         !! Manning roughness for shelf-side bottom drag.
      real(wp) :: coriolis_f = 0.0_wp
         !! Beta-plane / f-plane Coriolis parameter (1/s).
   contains
      procedure, non_overridable :: init => barotropic_state_init
      procedure, non_overridable :: destroy => barotropic_state_destroy
      procedure, non_overridable :: enter_data => barotropic_state_enter_data
      procedure, non_overridable :: exit_data => barotropic_state_exit_data
      procedure, non_overridable :: bytes => barotropic_state_bytes
   end type barotropic_state_t