mom_barotropic mom_barotropic::barotropic_cs mom_barotropic::bt_obc_type mom_barotropic::local_bt_cont_u_type mom_barotropic::local_bt_cont_v_type mom_barotropic::memory_size_type integer integer mom_barotropic::id_clock_sync id_clock_sync =-1 CPU time clock IDs. barotropic_init set_dtbt integer integer mom_barotropic::id_clock_calc id_clock_calc =-1 CPU time clock IDs. barotropic_init btstep integer integer mom_barotropic::id_clock_calc_pre id_clock_calc_pre =-1 CPU time clock IDs. barotropic_init btstep set_local_bt_cont_types integer integer mom_barotropic::id_clock_calc_post id_clock_calc_post =-1 CPU time clock IDs. barotropic_init btstep integer integer mom_barotropic::id_clock_pass_step id_clock_pass_step =-1 CPU time clock IDs. barotropic_init btstep integer integer mom_barotropic::id_clock_pass_pre id_clock_pass_pre =-1 CPU time clock IDs. barotropic_init btstep set_local_bt_cont_types integer integer mom_barotropic::id_clock_pass_post id_clock_pass_post =-1 CPU time clock IDs. barotropic_init btstep integer, parameter integer, parameter mom_barotropic::harmonic harmonic = 1 Enumeration values for various schemes. barotropic_init btcalc integer, parameter integer, parameter mom_barotropic::arithmetic arithmetic = 2 Enumeration values for various schemes. barotropic_init btcalc integer, parameter integer, parameter mom_barotropic::hybrid hybrid = 3 Enumeration values for various schemes. barotropic_init btcalc integer, parameter integer, parameter mom_barotropic::from_bt_cont from_bt_cont = 4 Enumeration values for various schemes. barotropic_init integer, parameter integer, parameter mom_barotropic::hybrid_bt_cont hybrid_bt_cont = 5 Enumeration values for various schemes. character *(20), parameter character*(20), parameter mom_barotropic::hybrid_string hybrid_string = "HYBRID" Enumeration values for various schemes. barotropic_init character *(20), parameter character*(20), parameter mom_barotropic::harmonic_string harmonic_string = "HARMONIC" Enumeration values for various schemes. barotropic_init character *(20), parameter character*(20), parameter mom_barotropic::arithmetic_string arithmetic_string = "ARITHMETIC" Enumeration values for various schemes. barotropic_init character *(20), parameter character*(20), parameter mom_barotropic::bt_cont_string bt_cont_string = "FROM_BT_CONT" Enumeration values for various schemes. barotropic_init subroutine, public subroutine, public mom_barotropic::btstep (U_in, V_in, eta_in, dt, bc_accel_u, bc_accel_v, forces, pbce, eta_PF_in, U_Cor, V_Cor, accel_layer_u, accel_layer_v, eta_out, uhbtav, vhbtav, G, GV, US, CS, visc_rem_u, visc_rem_v, etaav, ADp, OBC, BT_cont, eta_PF_start, taux_bot, tauy_bot, uh0, vh0, u_uh0, v_vh0) btstep U_in U_in V_in V_in eta_in eta_in dt dt bc_accel_u bc_accel_u bc_accel_v bc_accel_v forces forces pbce pbce eta_PF_in eta_PF_in U_Cor U_Cor V_Cor V_Cor accel_layer_u accel_layer_u accel_layer_v accel_layer_v eta_out eta_out uhbtav uhbtav vhbtav vhbtav G G GV GV US US CS CS visc_rem_u visc_rem_u visc_rem_v visc_rem_v etaav etaav ADp ADp OBC OBC BT_cont BT_cont eta_PF_start eta_PF_start taux_bot taux_bot tauy_bot tauy_bot uh0 uh0 vh0 vh0 u_uh0 u_uh0 v_vh0 v_vh0 This subroutine time steps the barotropic equations explicitly. For gravity waves, anything between a forwards-backwards scheme and a simulated backwards Euler scheme is used, with bebt between 0.0 and 1.0 determining the scheme. In practice, bebt must be of order 0.2 or greater. A forwards-backwards treatment of the Coriolis terms is always used. g The ocean's grid structure. gv The ocean's vertical grid structure. us A dimensional unit scaling type u_in The initial (3-D) zonal velocity [L T-1 ~> m s-1]. v_in The initial (3-D) meridional velocity [L T-1 ~> m s-1]. eta_in The initial barotropic free surface height anomaly or column mass anomaly [H ~> m or kg m-2]. dt The time increment to integrate over [T ~> s]. bc_accel_u The zonal baroclinic accelerations, [L T-2 ~> m s-2]. bc_accel_v The meridional baroclinic accelerations, [L T-2 ~> m s-2]. forces A structure with the driving mechanical forces pbce The baroclinic pressure anomaly in each layer due to free surface height anomalies [L2 H-1 T-2 ~> m s-2 or m4 kg-1 s-2]. eta_pf_in The 2-D eta field (either SSH anomaly or column mass anomaly) that was used to calculate the input pressure gradient accelerations (or its final value if eta_PF_start is provided [H ~> m or kg m-2]. Note: eta_in, pbce, and eta_PF_in must have up-to-date values in the first point of their halos. u_cor The (3-D) zonal velocities used to calculate the Coriolis terms in bc_accel_u [L T-1 ~> m s-1]. v_cor The (3-D) meridional velocities used to calculate the Coriolis terms in bc_accel_u [L T-1 ~> m s-1]. accel_layer_u The zonal acceleration of each layer due to the barotropic calculation [L T-2 ~> m s-2]. accel_layer_v The meridional acceleration of each layer due to the barotropic calculation [L T-2 ~> m s-2]. eta_out The final barotropic free surface height anomaly or column mass anomaly [H ~> m or kg m-2]. uhbtav the barotropic zonal volume or mass fluxes averaged through the barotropic steps [H L2 T-1 ~> m3 or kg s-1]. vhbtav the barotropic meridional volume or mass fluxes averaged through the barotropic steps [H L2 T-1 ~> m3 or kg s-1]. cs The control structure returned by a previous call to barotropic_init. visc_rem_u Both the fraction of the momentum originally in a layer that remains after a time-step of viscosity, and the fraction of a time-step's worth of a barotropic acceleration that a layer experiences after viscosity is applied, in the zonal direction. Nondimensional between 0 (at the bottom) and 1 (far above the bottom). visc_rem_v Ditto for meridional direction [nondim]. etaav The free surface height or column mass averaged over the barotropic integration [H ~> m or kg m-2]. adp Acceleration diagnostic pointers obc The open boundary condition structure. bt_cont A structure with elements that describe the effective open face areas as a function of barotropic flow. eta_pf_start The eta field consistent with the pressure gradient at the start of the barotropic stepping [H ~> m or kg m-2]. taux_bot The zonal bottom frictional stress from ocean to the seafloor [R L Z T-2 ~> Pa]. tauy_bot The meridional bottom frictional stress from ocean to the seafloor [R L Z T-2 ~> Pa]. uh0 The zonal layer transports at reference velocities [H L2 T-1 ~> m3 s-1 or kg s-1]. u_uh0 The velocities used to calculate uh0 [L T-1 ~> m s-1] vh0 The zonal layer transports at reference velocities [H L2 T-1 ~> m3 s-1 or kg s-1]. v_vh0 The velocities used to calculate vh0 [L T-1 ~> m s-1] adjust_local_bt_cont_types apply_velocity_obcs bt_cont_to_face_areas mom_domains::complete_group_pass mom_diag_mediator::enable_averaging find_duhbt_du find_dvhbt_dv find_face_areas find_uhbt find_vhbt id_clock_calc id_clock_calc_post id_clock_calc_pre id_clock_pass_post id_clock_pass_pre id_clock_pass_step mom_error_handler::is_root_pe mom_error_handler::mom_error mom_error_handler::mom_mesg mom_open_boundary::obc_direction_n mom_open_boundary::obc_direction_s mom_time_manager::real_to_time set_local_bt_cont_types set_up_bt_obc mom_domains::start_group_pass swap mom_tidal_forcing::tidal_forcing_sensitivity subroutine, public subroutine, public mom_barotropic::set_dtbt (G, GV, US, CS, eta, pbce, BT_cont, gtot_est, SSH_add) set_dtbt G G GV GV US US CS CS eta eta pbce pbce BT_cont BT_cont gtot_est gtot_est SSH_add SSH_add This subroutine automatically determines an optimal value for dtbt based on some state of the ocean. g The ocean's grid structure. gv The ocean's vertical grid structure. us A dimensional unit scaling type cs Barotropic control structure. eta The barotropic free surface height anomaly or column mass anomaly [H ~> m or kg m-2]. pbce The baroclinic pressure anomaly in each layer due to free surface height anomalies [L2 H-1 T-2 ~> m s-2 or m4 kg-1 s-2]. bt_cont A structure with elements that describe the effective open face areas as a function of barotropic flow. gtot_est An estimate of the total gravitational acceleration [L2 Z-1 T-2 ~> m s-2]. ssh_add An additional contribution to SSH to provide a margin of error when calculating the external wave speed [Z ~> m]. bt_cont_to_face_areas find_face_areas id_clock_sync mom_error_handler::mom_error mom_tidal_forcing::tidal_forcing_sensitivity barotropic_init mom_dynamics_split_rk2::step_mom_dyn_split_rk2 subroutine subroutine mom_barotropic::apply_velocity_obcs (OBC, ubt, vbt, uhbt, vhbt, ubt_trans, vbt_trans, eta, ubt_old, vbt_old, BT_OBC, G, MS, US, halo, dtbt, bebt, use_BT_cont, integral_BT_cont, dt_elapsed, Datu, Datv, BTCL_u, BTCL_v, uhbt0, vhbt0, ubt_int, vbt_int, uhbt_int, vhbt_int) apply_velocity_obcs OBC OBC ubt ubt vbt vbt uhbt uhbt vhbt vhbt ubt_trans ubt_trans vbt_trans vbt_trans eta eta ubt_old ubt_old vbt_old vbt_old BT_OBC BT_OBC G G MS MS US US halo halo dtbt dtbt bebt bebt use_BT_cont use_BT_cont integral_BT_cont integral_BT_cont dt_elapsed dt_elapsed Datu Datu Datv Datv BTCL_u BTCL_u BTCL_v BTCL_v uhbt0 uhbt0 vhbt0 vhbt0 ubt_int ubt_int vbt_int vbt_int uhbt_int uhbt_int vhbt_int vhbt_int The following 4 subroutines apply the open boundary conditions. This subroutine applies the open boundary conditions on barotropic velocities and mass transports, as developed by Mehmet Ilicak. obc An associated pointer to an OBC type. g The ocean's grid structure. ms A type that describes the memory sizes of the argument arrays. ubt the zonal barotropic velocity [L T-1 ~> m s-1]. uhbt the zonal barotropic transport [H L2 T-1 ~> m3 s-1 or kg s-1]. ubt_trans The zonal barotropic velocity used in transport [L T-1 ~> m s-1]. vbt The meridional barotropic velocity [L T-1 ~> m s-1]. vhbt the meridional barotropic transport [H L2 T-1 ~> m3 s-1 or kg s-1]. vbt_trans the meridional BT velocity used in transports [L T-1 ~> m s-1]. eta The barotropic free surface height anomaly or column mass anomaly [H ~> m or kg m-2]. ubt_old The starting value of ubt in a barotropic step [L T-1 ~> m s-1]. vbt_old The starting value of vbt in a barotropic step [L T-1 ~> m s-1]. bt_obc A structure with the private barotropic arrays related to the open boundary conditions, set by set_up_BT_OBC. us A dimensional unit scaling type halo The extra halo size to use here. dtbt The time step [T ~> s]. bebt The fractional weighting of the future velocity in determining the transport. use_bt_cont If true, use the BT_cont_types to calculate transports. integral_bt_cont If true, update the barotropic continuity equation directly from the initial condition using the time-integrated barotropic velocity. dt_elapsed The amount of time in the barotropic stepping that will have elapsed [T ~> s]. datu A fixed estimate of the face areas at u points [H L ~> m2 or kg m-1]. datv A fixed estimate of the face areas at v points [H L ~> m2 or kg m-1]. btcl_u Structure of information used for a dynamic estimate of the face areas at u-points. btcl_v Structure of information used for a dynamic estimate of the face areas at v-points. uhbt0 A correction to the zonal transport so that the barotropic functions agree with the sum of the layer transports [H L2 T-1 ~> m3 s-1 or kg s-1]. vhbt0 A correction to the meridional transport so that the barotropic functions agree with the sum of the layer transports [H L2 T-1 ~> m3 s-1 or kg s-1]. ubt_int The time-integrated zonal barotropic velocity before this update [L T-1 ~> m s-1]. uhbt_int The time-integrated zonal barotropic transport [H L2 T-1 ~> m3 s-1 or kg s-1]. vbt_int The time-integrated meridional barotropic velocity before this update [L T-1 ~> m s-1]. vhbt_int The time-integrated meridional barotropic transport [H L2 T-1 ~> m3 s-1 or kg s-1]. find_uhbt find_vhbt mom_open_boundary::obc_direction_n mom_open_boundary::obc_direction_s btstep subroutine subroutine mom_barotropic::set_up_bt_obc (OBC, eta, BT_OBC, BT_Domain, G, GV, US, MS, halo, use_BT_cont, integral_BT_cont, dt_baroclinic, Datu, Datv, BTCL_u, BTCL_v) set_up_bt_obc OBC OBC eta eta BT_OBC BT_OBC BT_Domain BT_Domain G G GV GV US US MS MS halo halo use_BT_cont use_BT_cont integral_BT_cont integral_BT_cont dt_baroclinic dt_baroclinic Datu Datu Datv Datv BTCL_u BTCL_u BTCL_v BTCL_v This subroutine sets up the private structure used to apply the open boundary conditions, as developed by Mehmet Ilicak. obc An associated pointer to an OBC type. ms A type that describes the memory sizes of the argument arrays. eta The barotropic free surface height anomaly or column mass anomaly [H ~> m or kg m-2]. bt_obc A structure with the private barotropic arrays related to the open boundary conditions, set by set_up_BT_OBC. bt_domain MOM_domain_type associated with wide arrays g The ocean's grid structure. gv The ocean's vertical grid structure. us A dimensional unit scaling type halo The extra halo size to use here. use_bt_cont If true, use the BT_cont_types to calculate transports. integral_bt_cont If true, update the barotropic continuity equation directly from the initial condition using the time-integrated barotropic velocity. dt_baroclinic The baroclinic timestep for this cycle of updates to the barotropic solver [T ~> s] datu A fixed estimate of the face areas at u points [H L ~> m2 or kg m-1]. datv A fixed estimate of the face areas at v points [H L ~> m2 or kg m-1]. btcl_u Structure of information used for a dynamic estimate of the face areas at u-points. btcl_v Structure of information used for a dynamic estimate of the face areas at v-points. mom_error_handler::mom_error mom_open_boundary::obc_direction_n mom_open_boundary::obc_direction_s uhbt_to_ubt vhbt_to_vbt btstep subroutine subroutine mom_barotropic::destroy_bt_obc (BT_OBC) destroy_bt_obc BT_OBC BT_OBC Clean up the BT_OBC memory. bt_obc A structure with the private barotropic arrays related to the open boundary conditions, set by set_up_BT_OBC. barotropic_end subroutine, public subroutine, public mom_barotropic::btcalc (h, G, GV, CS, h_u, h_v, may_use_default, OBC) btcalc h h G G GV GV CS CS h_u h_u h_v h_v may_use_default may_use_default OBC OBC btcalc calculates the barotropic velocities from the full velocity and thickness fields, determines the fraction of the total water column in each layer at velocity points, and determines a corrective fictitious mass source that will drive the barotropic estimate of the free surface height toward the baroclinic estimate. g The ocean's grid structure. gv The ocean's vertical grid structure. h Layer thicknesses [H ~> m or kg m-2]. cs The control structure returned by a previous call to barotropic_init. h_u The specified thicknesses at u-points [H ~> m or kg m-2]. h_v The specified thicknesses at v-points [H ~> m or kg m-2]. may_use_default An optional logical argument to indicate that the default velocity point thicknesses may be used for this particular calculation, even though the setting of CShvel_scheme would usually require that h_u and h_v be passed in. obc Open boundary control structure. arithmetic harmonic hybrid mom_error_handler::mom_error mom_open_boundary::obc_direction_n mom_open_boundary::obc_direction_s barotropic_init real function real function mom_barotropic::find_uhbt (u, BTC) find_uhbt u u BTC BTC The function find_uhbt determines the zonal transport for a given velocity, or with INTEGRAL_BT_CONT=True it determines the time-integrated zonal transport for a given time-integrated velocity. u The local zonal velocity [L T-1 ~> m s-1] or time integrated velocity [L ~> m] btc A structure containing various fields that allow the barotropic transports to be calculated consistently with the layers' continuity equations. The dimensions of some of the elements in this type vary depending on INTEGRAL_BT_CONT. The zonal barotropic transport [L2 H T-1 ~> m3 s-1] or time integrated transport [L2 H ~> m3] apply_velocity_obcs btstep real function real function mom_barotropic::find_duhbt_du (u, BTC) find_duhbt_du u u BTC BTC The function find_duhbt_du determines the marginal zonal face area for a given velocity, or with INTEGRAL_BT_CONT=True for a given time-integrated velocity. u The local zonal velocity [L T-1 ~> m s-1] or time integrated velocity [L ~> m] btc A structure containing various fields that allow the barotropic transports to be calculated consistently with the layers' continuity equations. The dimensions of some of the elements in this type vary depending on INTEGRAL_BT_CONT. The zonal barotropic face area [L H ~> m2] btstep real function real function mom_barotropic::uhbt_to_ubt (uhbt, BTC, guess) uhbt_to_ubt uhbt uhbt BTC BTC guess guess This function inverts the transport function to determine the barotopic velocity that is consistent with a given transport, or if INTEGRAL_BT_CONT=True this finds the time-integrated velocity that is consistent with a time-integrated transport. uhbt The barotropic zonal transport that should be inverted for, [H L2 T-1 ~> m3 s-1 or kg s-1] or the time-integrated transport [H L2 ~> m3 or kg]. btc A structure containing various fields that allow the barotropic transports to be calculated consistently with the layers' continuity equations. The dimensions of some of the elements in this type vary depending on INTEGRAL_BT_CONT. guess A guess at what ubt will be [L T-1 ~> m s-1] or [L ~> m]. The result is not allowed to be dramatically larger than guess. The result - The velocity that gives uhbt transport [L T-1 ~> m s-1] or the time-integrated velocity [L ~> m]. set_up_bt_obc real function real function mom_barotropic::find_vhbt (v, BTC) find_vhbt v v BTC BTC The function find_vhbt determines the meridional transport for a given velocity, or with INTEGRAL_BT_CONT=True it determines the time-integrated meridional transport for a given time-integrated velocity. v The local meridional velocity [L T-1 ~> m s-1] or time integrated velocity [L ~> m] btc A structure containing various fields that allow the barotropic transports to be calculated consistently with the layers' continuity equations. The dimensions of some of the elements in this type vary depending on INTEGRAL_BT_CONT. The meridional barotropic transport [L2 H T-1 ~> m3 s-1] or time integrated transport [L2 H ~> m3] apply_velocity_obcs btstep real function real function mom_barotropic::find_dvhbt_dv (v, BTC) find_dvhbt_dv v v BTC BTC The function find_dvhbt_dv determines the marginal meridional face area for a given velocity, or with INTEGRAL_BT_CONT=True for a given time-integrated velocity. v The local meridional velocity [L T-1 ~> m s-1] or time integrated velocity [L ~> m] btc A structure containing various fields that allow the barotropic transports to be calculated consistently with the layers' continuity equations. The dimensions of some of the elements in this type vary depending on INTEGRAL_BT_CONT. The meridional barotropic face area [L H ~> m2] btstep real function real function mom_barotropic::vhbt_to_vbt (vhbt, BTC, guess) vhbt_to_vbt vhbt vhbt BTC BTC guess guess This function inverts the transport function to determine the barotopic velocity that is consistent with a given transport, or if INTEGRAL_BT_CONT=True this finds the time-integrated velocity that is consistent with a time-integrated transport. vhbt The barotropic meridional transport that should be inverted for [H L2 T-1 ~> m3 s-1 or kg s-1] or the time-integrated transport [H L2 ~> m3 or kg]. btc A structure containing various fields that allow the barotropic transports to be calculated consistently with the layers' continuity equations. The dimensions of some of the elements in this type vary depending on INTEGRAL_BT_CONT. guess A guess at what vbt will be [L T-1 ~> m s-1] or [L ~> m]. The result is not allowed to be dramatically larger than guess. The result - The velocity that gives vhbt transport [L T-1 ~> m s-1] or the time-integrated velocity [L ~> m]. set_up_bt_obc subroutine subroutine mom_barotropic::set_local_bt_cont_types (BT_cont, BTCL_u, BTCL_v, G, US, MS, BT_Domain, halo, dt_baroclinic) set_local_bt_cont_types BT_cont BT_cont BTCL_u BTCL_u BTCL_v BTCL_v G G US US MS MS BT_Domain BT_Domain halo halo dt_baroclinic dt_baroclinic This subroutine sets up reordered versions of the BT_cont type in the local_BT_cont types, which have wide halos properly filled in. bt_cont The BT_cont_type input to the barotropic solver. ms A type that describes the memory sizes of the argument arrays. btcl_u A structure with the u information from BT_cont. btcl_v A structure with the v information from BT_cont. g The ocean's grid structure. us A dimensional unit scaling type bt_domain The domain to use for updating the halos of wide arrays. halo The extra halo size to use here. dt_baroclinic The baroclinic time step [T ~> s], which is provided if INTEGRAL_BT_CONTINUITY is true. id_clock_calc_pre id_clock_pass_pre swap btstep subroutine subroutine mom_barotropic::adjust_local_bt_cont_types (ubt, uhbt, vbt, vhbt, BTCL_u, BTCL_v, G, US, MS, halo, dt_baroclinic) adjust_local_bt_cont_types ubt ubt uhbt uhbt vbt vbt vhbt vhbt BTCL_u BTCL_u BTCL_v BTCL_v G G US US MS MS halo halo dt_baroclinic dt_baroclinic Adjust_local_BT_cont_types expands the range of velocities with a cubic curve translating velocities into transports to match the inital values of velocities and summed transports when the velocities are larger than the first guesses of the cubic transition velocities used to set up the local_BT_cont types. ms A type that describes the memory sizes of the argument arrays. ubt The linearization zonal barotropic velocity [L T-1 ~> m s-1]. uhbt The linearization zonal barotropic transport vbt The linearization meridional barotropic velocity [L T-1 ~> m s-1]. vhbt The linearization meridional barotropic transport btcl_u A structure with the u information from BT_cont. btcl_v A structure with the v information from BT_cont. g The ocean's grid structure. us A dimensional unit scaling type halo The extra halo size to use here. dt_baroclinic The baroclinic time step [T ~> s], which is provided if INTEGRAL_BT_CONTINUITY is true. btstep subroutine subroutine mom_barotropic::bt_cont_to_face_areas (BT_cont, Datu, Datv, G, US, MS, halo, maximize) bt_cont_to_face_areas BT_cont BT_cont Datu Datu Datv Datv G G US US MS MS halo halo maximize maximize This subroutine uses the BTCL types to find typical or maximum face areas, which can then be used for finding wave speeds, etc. bt_cont The BT_cont_type input to the barotropic solver. ms A type that describes the memory sizes of the argument arrays. datu The effective zonal face area [H L ~> m2 or kg m-1]. datv The effective meridional face area [H L ~> m2 or kg m-1]. g The ocean's grid structure. us A dimensional unit scaling type halo The extra halo size to use here. maximize If present and true, find the maximum face area for any velocity. btstep set_dtbt subroutine subroutine mom_barotropic::swap (a, b) swap a a b b Swap the values of two real variables. a The first variable to be swapped. b The second variable to be swapped. btstep set_local_bt_cont_types subroutine subroutine mom_barotropic::find_face_areas (Datu, Datv, G, GV, US, CS, MS, eta, halo, add_max) find_face_areas Datu Datu Datv Datv G G GV GV US US CS CS MS MS eta eta halo halo add_max add_max This subroutine determines the open face areas of cells for calculating the barotropic transport. ms A type that describes the memory sizes of the argument arrays. datu The open zonal face area [H L ~> m2 or kg m-1]. datv The open meridional face area [H L ~> m2 or kg m-1]. g The ocean's grid structure. gv The ocean's vertical grid structure. us A dimensional unit scaling type cs The control structure returned by a previous call to barotropic_init. eta The barotropic free surface height anomaly halo The halo size to use, default = 1. add_max A value to add to the maximum depth (used to overestimate the external wave speed) [Z ~> m]. barotropic_init btstep set_dtbt subroutine, public subroutine, public mom_barotropic::bt_mass_source (h, eta, set_cor, G, GV, CS) bt_mass_source h h eta eta set_cor set_cor G G GV GV CS CS bt_mass_source determines the appropriately limited mass source for the barotropic solver, along with a corrective fictitious mass source that will drive the barotropic estimate of the free surface height toward the baroclinic estimate. g The ocean's grid structure. gv The ocean's vertical grid structure. h Layer thicknesses [H ~> m or kg m-2]. eta The free surface height that is to be corrected [H ~> m or kg m-2]. set_cor A flag to indicate whether to set the corrective fluxes (and update the slowly varying part of eta_cor) (.true.) or whether to incrementally update the corrective fluxes. cs The control structure returned by a previous call to barotropic_init. mom_error_handler::mom_error subroutine, public subroutine, public mom_barotropic::barotropic_init (u, v, h, eta, Time, G, GV, US, param_file, diag, CS, restart_CS, calc_dtbt, BT_cont, tides_CSp) barotropic_init u u v v h h eta eta Time Time G G GV GV US US param_file param_file diag diag CS CS restart_CS restart_CS calc_dtbt calc_dtbt BT_cont BT_cont tides_CSp tides_CSp barotropic_init initializes a number of time-invariant fields used in the barotropic calculation and initializes any barotropic fields that have not already been initialized. g The ocean's grid structure. gv The ocean's vertical grid structure. us A dimensional unit scaling type u The zonal velocity [L T-1 ~> m s-1]. v The meridional velocity [L T-1 ~> m s-1]. h Layer thicknesses [H ~> m or kg m-2]. eta Free surface height or column mass anomaly time The current model time. param_file A structure to parse for run-time parameters. diag A structure that is used to regulate diagnostic output. cs A pointer to the control structure for this module that is set in register_barotropic_restarts. restart_cs A pointer to the restart control structure. calc_dtbt If true, the barotropic time step must be recalculated before stepping. bt_cont A structure with elements that describe the tides_csp A pointer to the control structure of the arithmetic arithmetic_string bt_cont_string btcalc mom_cpu_clock::cpu_clock_id find_face_areas from_bt_cont harmonic harmonic_string hybrid hybrid_string id_clock_calc id_clock_calc_post id_clock_calc_pre id_clock_pass_post id_clock_pass_pre id_clock_pass_step id_clock_sync mom_error_handler::mom_error mom_error_handler::mom_mesg set_dtbt subroutine, public subroutine, public mom_barotropic::barotropic_get_tav (CS, ubtav, vbtav, G, US) barotropic_get_tav CS CS ubtav ubtav vbtav vbtav G G US US Copies ubtav and vbtav from private type into arrays. cs Control structure for this module g Grid structure ubtav Zonal barotropic velocity averaged over a baroclinic timestep [L T-1 ~> m s-1] vbtav Meridional barotropic velocity averaged over a baroclinic timestep [L T-1 ~> m s-1] us A dimensional unit scaling type mom_hor_visc::horizontal_viscosity subroutine, public subroutine, public mom_barotropic::barotropic_end (CS) barotropic_end CS CS Clean up the barotropic control structure. cs Control structure to clear out. destroy_bt_obc subroutine, public subroutine, public mom_barotropic::register_barotropic_restarts (HI, GV, param_file, CS, restart_CS) register_barotropic_restarts HI HI GV GV param_file param_file CS CS restart_CS restart_CS This subroutine is used to register any fields from MOM_barotropic.F90 that should be written to or read from the restart file. hi A horizontal index type structure. param_file A structure to parse for run-time parameters. cs A pointer that is set to point to the control structure for this module. gv The ocean's vertical grid structure. restart_cs A pointer to the restart control structure. mom_error_handler::mom_error mom_io::var_desc Baropotric solver. By Robert Hallberg, April 1994 - January 2007.This program contains the subroutines that time steps the linearized barotropic equations. btstep is used to actually time step the barotropic equations, and contains most of the substance of this module.btstep uses a forwards-backwards based scheme to time step the barotropic equations, returning the layers' accelerations due to the barotropic changes in the ocean state, the final free surface height (or column mass), and the volume (or mass) fluxes summed through the layers and averaged over the baroclinic time step. As input, btstep takes the initial 3-D velocities, the inital free surface height, the 3-D accelerations of the layers, and the external forcing. Everything in btstep is cast in terms of anomalies, so if everything is in balance, there is explicitly no acceleration due to btstep.The spatial discretization of the continuity equation is second order accurate. A flux conservative form is used to guarantee global conservation of volume. The spatial discretization of the momentum equation is second order accurate. The Coriolis force is written in a form which does not contribute to the energy tendency and which conserves linearized potential vorticity, f/D. These terms are exactly removed from the baroclinic momentum equations, so the linearization of vorticity advection will not degrade the overall solution.btcalc calculates the fractional thickness of each layer at the velocity points, for later use in calculating the barotropic velocities and the averaged accelerations. Harmonic mean thicknesses (i.e. 2*h_L*h_R/(h_L + h_R)) are used to avoid overly strong weighting of overly thin layers. This may later be relaxed to use thicknesses determined from the continuity equations.bt_mass_source determines the real mass sources for the barotropic solver, along with the corrective pseudo-fluxes that keep the barotropic and baroclinic estimates of the free surface height close to each other. Given the layer thicknesses and the free surface height that correspond to each other, it calculates a corrective mass source that is added to the barotropic continuity* equation, and optionally adjusts a slowly varying correction rate. Newer algorithmic changes have deemphasized the need for this, but it is still here to add net water sources to the barotropic solver.*barotropic_init allocates and initializes any barotropic arrays that have not been read from a restart file, reads parameters from the inputfile, and sets up diagnostic fields.barotropic_end deallocates anything allocated in barotropic_init or register_barotropic_restarts.register_barotropic_restarts is used to indicate any fields that are private to the barotropic solver that need to be included in the restart files, and to ensure that they are read.