mom_forcing_type mom_forcing_type::allocate_forcing_type mom_forcing_type::allocate_mech_forcing mom_forcing_type::forcing mom_forcing_type::forcing_diags mom_forcing_type::mech_forcing subroutine, public subroutine, public mom_forcing_type::extractfluxes1d (G, GV, US, fluxes, optics, nsw, j, dt, FluxRescaleDepth, useRiverHeatContent, useCalvingHeatContent, h, T, netMassInOut, netMassOut, net_heat, net_salt, pen_SW_bnd, tv, aggregate_FW, nonpenSW, netmassInOut_rate, net_Heat_Rate, net_salt_rate, pen_sw_bnd_Rate, skip_diags) extractfluxes1d G G GV GV US US fluxes fluxes optics optics nsw nsw j j dt dt FluxRescaleDepth FluxRescaleDepth useRiverHeatContent useRiverHeatContent useCalvingHeatContent useCalvingHeatContent h h T T netMassInOut netMassInOut netMassOut netMassOut net_heat net_heat net_salt net_salt pen_SW_bnd pen_SW_bnd tv tv aggregate_FW aggregate_FW nonpenSW nonpenSW netmassInOut_rate netmassInOut_rate net_Heat_Rate net_Heat_Rate net_salt_rate net_salt_rate pen_sw_bnd_Rate pen_sw_bnd_Rate skip_diags skip_diags This subroutine extracts fluxes from the surface fluxes type. It works on a j-row for optimization purposes. The 2d (i,j) wrapper is the next subroutine below. This routine multiplies fluxes by dt, so that the result is an accumulation of fluxes over a time step. g ocean grid structure gv ocean vertical grid structure us A dimensional unit scaling type fluxes structure containing pointers to possible forcing fields. NULL unused fields. optics pointer to optics nsw number of bands of penetrating SW j j-index to work on dt The time step for these fluxes [T ~> s] fluxrescaledepth min ocean depth before fluxes are scaled away [H ~> m or kg m-2] useriverheatcontent logical for river heat content usecalvingheatcontent logical for calving heat content h layer thickness [H ~> m or kg m-2] t layer temperatures [degC] netmassinout net mass flux (non-Bouss) or volume flux (if Bouss) of water in/out of ocean over a time step [H ~> m or kg m-2] netmassout net mass flux (non-Bouss) or volume flux (if Bouss) of water leaving ocean surface over a time step [H ~> m or kg m-2]. netMassOut < 0 means mass leaves ocean. net_heat net heat at the surface accumulated over a time step for coupler + restoring. Exclude two terms from net_heat: (1) downwelling (penetrative) SW, (2) evaporation heat content, (since do not yet know evap temperature). [degC H ~> degC m or degC kg m-2]. net_salt surface salt flux into the ocean accumulated over a time step [ppt H ~> ppt m or ppt kg m-2]. pen_sw_bnd penetrating SW flux, split into bands. [degC H ~> degC m or degC kg m-2] and array size nsw x G isd: G ied, where nsw=number of SW bands in pen_SW_bnd. This heat flux is not part of net_heat. tv structure containing pointers to available thermodynamic fields. Used to keep track of the heat flux associated with net mass fluxes into the ocean. aggregate_fw For determining how to aggregate forcing. nonpensw Non-penetrating SW used in net_heat net_heat_rate Rate of net surface heating net_salt_rate Surface salt flux into the ocean netmassinout_rate Rate of net mass flux into the ocean pen_sw_bnd_rate Rate of penetrative shortwave heating skip_diags If present and true, skip calculating diagnostics mom_opacity::extract_optics_slice mom_error_handler::mom_error mom_opacity::optics_nbands mom_diabatic_aux::applyboundaryfluxesinout mom_bulk_mixed_layer::bulkmixedlayer calculatebuoyancyflux1d extractfluxes2d subroutine, public subroutine, public mom_forcing_type::extractfluxes2d (G, GV, US, fluxes, optics, nsw, dt, FluxRescaleDepth, useRiverHeatContent, useCalvingHeatContent, h, T, netMassInOut, netMassOut, net_heat, Net_salt, Pen_SW_bnd, tv, aggregate_FW) extractfluxes2d G G GV GV US US fluxes fluxes optics optics nsw nsw dt dt FluxRescaleDepth FluxRescaleDepth useRiverHeatContent useRiverHeatContent useCalvingHeatContent useCalvingHeatContent h h T T netMassInOut netMassInOut netMassOut netMassOut net_heat net_heat Net_salt Net_salt Pen_SW_bnd Pen_SW_bnd tv tv aggregate_FW aggregate_FW 2d wrapper for 1d extract fluxes from surface fluxes type. This subroutine extracts fluxes from the surface fluxes type. It multiplies the fluxes by dt, so that the result is an accumulation of the fluxes over a time step. g ocean grid structure gv ocean vertical grid structure us A dimensional unit scaling type fluxes structure containing pointers to forcing. optics pointer to optics nsw number of bands of penetrating SW dt The time step for these fluxes [T ~> s] fluxrescaledepth min ocean depth before fluxes are scaled away [H ~> m or kg m-2] useriverheatcontent logical for river heat content usecalvingheatcontent logical for calving heat content h layer thickness [H ~> m or kg m-2] t layer temperatures [degC] netmassinout net mass flux (non-Bouss) or volume flux (if Bouss) of water in/out of ocean over a time step [H ~> m or kg m-2] netmassout net mass flux (non-Bouss) or volume flux (if Bouss) of water leaving ocean surface over a time step [H ~> m or kg m-2]. net_heat net heat at the surface accumulated over a time step associated with coupler + restore. Exclude two terms from net_heat: (1) downwelling (penetrative) SW, (2) evaporation heat content, (since do not yet know temperature of evap). [degC H ~> degC m or degC kg m-2] net_salt surface salt flux into the ocean accumulated over a time step [ppt H ~> ppt m or ppt kg m-2] pen_sw_bnd penetrating SW flux, by frequency band [degC H ~> degC m or degC kg m-2] with array size nsw x G isd: G ied, where nsw=number of SW bands in pen_SW_bnd. This heat flux is not in net_heat. tv structure containing pointers to available thermodynamic fields. Here it is used to keep track of the heat flux associated with net mass fluxes into the ocean. aggregate_fw For determining how to aggregate the forcing. extractfluxes1d subroutine, public subroutine, public mom_forcing_type::calculatebuoyancyflux1d (G, GV, US, fluxes, optics, nsw, h, Temp, Salt, tv, j, buoyancyFlux, netHeatMinusSW, netSalt, skip_diags) calculatebuoyancyflux1d G G GV GV US US fluxes fluxes optics optics nsw nsw h h Temp Temp Salt Salt tv tv j j buoyancyFlux buoyancyFlux netHeatMinusSW netHeatMinusSW netSalt netSalt skip_diags skip_diags This routine calculates surface buoyancy flux by adding up the heat, FW & salt fluxes. These are actual fluxes, with units of stuff per time. Setting dt=1 in the call to extractFluxes routine allows us to get "stuf per time" rather than the time integrated fluxes needed in other routines that call extractFluxes. g ocean grid gv ocean vertical grid structure us A dimensional unit scaling type fluxes surface fluxes optics penetrating SW optics nsw The number of frequency bands of penetrating shortwave radiation h layer thickness [H ~> m or kg m-2] temp prognostic temp [degC] salt salinity [ppt] tv thermodynamics type j j-row to work on buoyancyflux buoyancy fluxes [L2 T-3 ~> m2 s-3] netheatminussw surf Heat flux [degC H s-1 ~> degC m s-1 or degC kg m-2 s-1] netsalt surf salt flux [ppt H s-1 ~> ppt m s-1 or ppt kg m-2 s-1] skip_diags If present and true, skip calculating diagnostics inside extractFluxes1d() mom_eos::eos_domain extractfluxes1d mom_opacity::optics_nbands mom_opacity::sumswoverbands calculatebuoyancyflux2d subroutine, public subroutine, public mom_forcing_type::calculatebuoyancyflux2d (G, GV, US, fluxes, optics, h, Temp, Salt, tv, buoyancyFlux, netHeatMinusSW, netSalt, skip_diags) calculatebuoyancyflux2d G G GV GV US US fluxes fluxes optics optics h h Temp Temp Salt Salt tv tv buoyancyFlux buoyancyFlux netHeatMinusSW netHeatMinusSW netSalt netSalt skip_diags skip_diags Calculates surface buoyancy flux by adding up the heat, FW and salt fluxes, for 2d arrays. This is a wrapper for calculateBuoyancyFlux1d. g ocean grid gv ocean vertical grid structure us A dimensional unit scaling type fluxes surface fluxes optics SW ocean optics h layer thickness [H ~> m or kg m-2] temp temperature [degC] salt salinity [ppt] tv thermodynamics type buoyancyflux buoyancy fluxes [L2 T-3 ~> m2 s-3] netheatminussw surf temp flux [degC H ~> degC m or degC kg m-2] netsalt surf salt flux [ppt H ~> ppt m or ppt kg m-2] skip_diags If present and true, skip calculating diagnostics inside extractFluxes1d() calculatebuoyancyflux1d mom_opacity::optics_nbands mom_diabatic_driver::diabatic_ale mom_diabatic_driver::diabatic_ale_legacy mom_diabatic_driver::layered_diabatic subroutine, public subroutine, public mom_forcing_type::mom_forcing_chksum (mesg, fluxes, G, US, haloshift) mom_forcing_chksum mesg mesg fluxes fluxes G G US US haloshift haloshift Write out chksums for thermodynamic fluxes. mesg message fluxes A structure containing thermodynamic forcing fields g grid type us A dimensional unit scaling type haloshift shift in halo mom_main subroutine, public subroutine, public mom_forcing_type::mom_mech_forcing_chksum (mesg, forces, G, US, haloshift) mom_mech_forcing_chksum mesg mesg forces forces G G US US haloshift haloshift Write out chksums for the driving mechanical forces. mesg message forces A structure with the driving mechanical forces g grid type us A dimensional unit scaling type haloshift shift in halo mom_main subroutine subroutine mom_forcing_type::mech_forcing_singlepointprint (forces, G, i, j, mesg) mech_forcing_singlepointprint forces forces G G i i j j mesg mesg Write out values of the mechanical forcing arrays at the i,j location. This is a debugging tool. forces A structure with the driving mechanical forces g Grid type mesg Message i i-index j j-index locmsg subroutine, public subroutine, public mom_forcing_type::forcing_singlepointprint (fluxes, G, i, j, mesg) forcing_singlepointprint fluxes fluxes G G i i j j mesg mesg Write out values of the fluxes arrays at the i,j location. This is a debugging tool. fluxes A structure containing thermodynamic forcing fields g Grid type mesg Message i i-index j j-index locmsg mom_diabatic_aux::applyboundaryfluxesinout subroutine, public subroutine, public mom_forcing_type::register_forcing_type_diags (Time, diag, US, use_temperature, handles, use_berg_fluxes) register_forcing_type_diags Time Time diag diag US US use_temperature use_temperature handles handles use_berg_fluxes use_berg_fluxes Register members of the forcing type for diagnostics. time time type diag diagnostic control type us A dimensional unit scaling type use_temperature True if T/S are in use handles handles for diagnostics use_berg_fluxes If true, allow iceberg flux diagnostics mom_cpu_clock::cpu_clock_id subroutine, public subroutine, public mom_forcing_type::forcing_accumulate (flux_tmp, forces, fluxes, G, wt2) forcing_accumulate flux_tmp flux_tmp forces forces fluxes fluxes G G wt2 wt2 Accumulate the forcing over time steps, taking input from a mechanical forcing type and a temporary forcing-flux type. flux_tmp A temporary structure with current thermodynamic forcing fields forces A structure with the driving mechanical forces fluxes A structure containing time-averaged thermodynamic forcing fields g The ocean's grid structure wt2 The relative weight of the new fluxes fluxes_accumulate subroutine, public subroutine, public mom_forcing_type::fluxes_accumulate (flux_tmp, fluxes, G, wt2, forces) fluxes_accumulate flux_tmp flux_tmp fluxes fluxes G G wt2 wt2 forces forces Accumulate the thermodynamic fluxes over time steps. flux_tmp A temporary structure with current thermodynamic forcing fields fluxes A structure containing time-averaged thermodynamic forcing fields g The ocean's grid structure wt2 The relative weight of the new fluxes forces A structure with the driving mechanical forces mom_error_handler::mom_error forcing_accumulate subroutine, public subroutine, public mom_forcing_type::copy_common_forcing_fields (forces, fluxes, G, skip_pres) copy_common_forcing_fields forces forces fluxes fluxes G G skip_pres skip_pres This subroutine copies the computational domains of common forcing fields from a mech_forcing type to a (thermodynamic) forcing type. forces A structure with the driving mechanical forces fluxes A structure containing thermodynamic forcing fields g grid type skip_pres If present and true, do not copy pressure fields. subroutine, public subroutine, public mom_forcing_type::set_derived_forcing_fields (forces, fluxes, G, US, Rho0) set_derived_forcing_fields forces forces fluxes fluxes G G US US Rho0 Rho0 This subroutine calculates certain derived forcing fields based on information from a mech_forcing type and stores them in a (thermodynamic) forcing type. forces A structure with the driving mechanical forces fluxes A structure containing thermodynamic forcing fields g grid type us A dimensional unit scaling type rho0 A reference density of seawater [R ~> kg m-3], as used to calculate ustar. subroutine, public subroutine, public mom_forcing_type::set_net_mass_forcing (fluxes, forces, G, US) set_net_mass_forcing fluxes fluxes forces forces G G US US This subroutine determines the net mass source to the ocean from a (thermodynamic) forcing type and stores it in a mech_forcing type. fluxes A structure containing thermodynamic forcing fields forces A structure with the driving mechanical forces us A dimensional unit scaling type g The ocean grid type get_net_mass_forcing subroutine, public subroutine, public mom_forcing_type::get_net_mass_forcing (fluxes, G, US, net_mass_src) get_net_mass_forcing fluxes fluxes G G US US net_mass_src net_mass_src This subroutine calculates determines the net mass source to the ocean from a (thermodynamic) forcing type and stores it in a provided array. fluxes A structure containing thermodynamic forcing fields g The ocean grid type us A dimensional unit scaling type net_mass_src The net mass flux of water into the ocean [kg m-2 s-1]. set_net_mass_forcing subroutine, public subroutine, public mom_forcing_type::copy_back_forcing_fields (fluxes, forces, G) copy_back_forcing_fields fluxes fluxes forces forces G G This subroutine copies the computational domains of common forcing fields from a mech_forcing type to a (thermodynamic) forcing type. fluxes A structure containing thermodynamic forcing fields forces A structure with the driving mechanical forces g grid type subroutine, public subroutine, public mom_forcing_type::mech_forcing_diags (forces_in, dt, G, time_end, diag, handles) mech_forcing_diags forces_in forces_in dt dt G G time_end time_end diag diag handles handles Offer mechanical forcing fields for diagnostics for those fields registered as part of register_forcing_type_diags. forces_in mechanical forcing input fields dt time step for the forcing [s] g grid type time_end The end time of the diagnostic interval. diag diagnostic type handles diagnostic id for diag_manager deallocate_mech_forcing mom_diag_mediator::disable_averaging mom_diag_mediator::enable_averaging rotate_mech_forcing mom_main ocean_model_mod::update_ocean_model subroutine, public subroutine, public mom_forcing_type::forcing_diagnostics (fluxes_in, sfc_state, G_in, US, time_end, diag, handles) forcing_diagnostics fluxes_in fluxes_in sfc_state sfc_state G_in G_in US US time_end time_end diag diag handles handles Offer buoyancy forcing fields for diagnostics for those fields registered as part of register_forcing_type_diags. fluxes_in A structure containing thermodynamic forcing fields sfc_state A structure containing fields that describe the surface state of the ocean. g_in Input grid type us A dimensional unit scaling type time_end The end time of the diagnostic interval. diag diagnostic regulator handles diagnostic ids deallocate_forcing_type mom_diag_mediator::disable_averaging mom_diag_mediator::enable_averages mom_spatial_means::global_area_integral mom_spatial_means::global_area_mean rotate_forcing mom_main ocean_model_mod::update_ocean_model subroutine subroutine mom_forcing_type::allocate_forcing_by_group (G, fluxes, water, heat, ustar, press, shelf, iceberg, salt, fix_accum_bug) allocate_forcing_by_group G G fluxes fluxes water water heat heat ustar ustar press press shelf shelf iceberg iceberg salt salt fix_accum_bug fix_accum_bug Conditionally allocate fields within the forcing type. g Ocean grid structure fluxes A structure containing thermodynamic forcing fields water If present and true, allocate water fluxes heat If present and true, allocate heat fluxes ustar If present and true, allocate ustar and related fields press If present and true, allocate p_surf and related fields shelf If present and true, allocate fluxes for ice-shelf iceberg If present and true, allocate fluxes for icebergs salt If present and true, allocate salt fluxes fix_accum_bug If present and true, avoid using a bug in accumulation of ustar_gustless myalloc subroutine subroutine mom_forcing_type::allocate_forcing_by_ref (fluxes_ref, G, fluxes) allocate_forcing_by_ref fluxes_ref fluxes_ref G G fluxes fluxes fluxes_ref Reference fluxes g Grid metric of target fluxes fluxes Target fluxes get_forcing_groups myalloc subroutine subroutine mom_forcing_type::allocate_mech_forcing_by_group (G, forces, stress, ustar, shelf, press, iceberg) allocate_mech_forcing_by_group G G forces forces stress stress ustar ustar shelf shelf press press iceberg iceberg Conditionally allocate fields within the mechanical forcing type using control flags. g Ocean grid structure forces Forcing fields structure stress If present and true, allocate taux, tauy ustar If present and true, allocate ustar and related fields shelf If present and true, allocate forces for ice-shelf press If present and true, allocate p_surf and related fields iceberg If present and true, allocate forces for icebergs myalloc subroutine subroutine mom_forcing_type::allocate_mech_forcing_from_ref (forces_ref, G, forces) allocate_mech_forcing_from_ref forces_ref forces_ref G G forces forces Conditionally allocate fields within the mechanical forcing type based on a reference forcing. forces_ref Reference forcing fields g Grid metric of target forcing forces Mechanical forcing fields get_mech_forcing_groups subroutine subroutine mom_forcing_type::get_forcing_groups (fluxes, water, heat, ustar, press, shelf, iceberg, salt, heat_added, buoy) get_forcing_groups fluxes fluxes water water heat heat ustar ustar press press shelf shelf iceberg iceberg salt salt heat_added heat_added buoy buoy Return flags indicating which groups of forcings are allocated. fluxes Reference flux fields water True if fluxes contains water-based fluxes heat True if fluxes contains heat-based fluxes ustar True if fluxes contains ustar fluxes press True if fluxes contains surface pressure shelf True if fluxes contains ice shelf fields iceberg True if fluxes contains iceberg fluxes salt True if fluxes contains salt flux heat_added True if fluxes contains explicit heat buoy True if fluxes contains buoyancy fluxes allocate_forcing_by_ref rotate_forcing subroutine subroutine mom_forcing_type::get_mech_forcing_groups (forces, stress, ustar, shelf, press, iceberg) get_mech_forcing_groups forces forces stress stress ustar ustar shelf shelf press press iceberg iceberg Return flags indicating which groups of mechanical forcings are allocated. forces Reference forcing fields stress True if forces contains wind stress fields ustar True if forces contains ustar field shelf True if forces contains ice shelf fields press True if forces contains pressure fields iceberg True if forces contains iceberg fields allocate_mech_forcing_from_ref rotate_mech_forcing subroutine subroutine mom_forcing_type::myalloc (array, is, ie, js, je, flag) myalloc array array is is ie ie js js je je flag flag Allocates and zeroes-out array. array Array to be allocated is Start i-index ie End i-index js Start j-index je End j-index flag Flag to indicate to allocate allocate_forcing_by_group allocate_forcing_by_ref allocate_mech_forcing_by_group subroutine, public subroutine, public mom_forcing_type::deallocate_forcing_type (fluxes) deallocate_forcing_type fluxes fluxes Deallocate the forcing type. fluxes Forcing fields structure forcing_diagnostics subroutine, public subroutine, public mom_forcing_type::deallocate_mech_forcing (forces) deallocate_mech_forcing forces forces Deallocate the mechanical forcing type. forces Forcing fields structure mech_forcing_diags subroutine, public subroutine, public mom_forcing_type::rotate_forcing (fluxes_in, fluxes, turns) rotate_forcing fluxes_in fluxes_in fluxes fluxes turns turns fluxes_in Input forcing struct fluxes Rotated forcing struct turns Number of quarter turns get_forcing_groups mom_error_handler::mom_error forcing_diagnostics mom::step_mom subroutine, public subroutine, public mom_forcing_type::rotate_mech_forcing (forces_in, turns, forces) rotate_mech_forcing forces_in forces_in turns turns forces forces forces_in Forcing on the input domain turns Number of quarter-turns forces Forcing on the rotated domain get_mech_forcing_groups mech_forcing_diags mom::step_mom This module implements boundary forcing for MOM6. The ocean is a forced-dissipative system. Forcing occurs at the boundaries, and this module mediates the various forcing terms from momentum, heat, salt, and mass. Boundary fluxes from other tracers are treated by coupling to biogeochemical models. We here present elements of how MOM6 assumes boundary fluxes are passed into the ocean. Note that all fluxes are positive into the ocean. For surface boundary fluxes, that means fluxes are positive downward. For example, a positive shortwave flux warms the ocean. The ocean surface exchanges momentum with the overlying atmosphere, sea ice, and land ice. The momentum is exchanged as a horizontal stress (Newtons per squared meter: N/m2) imposed on the upper ocean grid cell. The ocean gains or loses mass through evaporation, precipitation, sea ice melt/form, and and river runoff. Positive mass fluxes add mass to the liquid ocean. The boundary mass flux units are (kilogram per square meter per sec: kg/(m2/sec)). Evaporation field can in fact represent a mass loss (evaporation) or mass gain (condensation in foggy areas). sea ice formation leads to mass moving from the liquid ocean to the ice model, and melt adds liquid to the ocean. Precipitation can be liquid or frozen (snow). Furthermore, in some versions of the GFDL coupler, precipitation can be negative. The reason is that the ice model combines precipitation with ice melt and ice formation. This limitation of the ice model diagnostics should be overcome future versions. River runoff can be liquid or frozen. Frozen runoff is often associated with calving land-ice and/or ice bergs. Over most of the ocean, there is no exchange of salt with the atmosphere. However, the liquid ocean exchanges salt with sea ice. When ice forms, it extracts salt from ice pockets and discharges the salt into the liquid ocean. The salt concentration of sea ice is therefore much lower (around 5ppt) than liquid seawater (around 30-35ppt in high latitudes). For ocean-ice models run with a prescribed atmosphere, such as in the CORE/OMMIP simulations, it is necessary to employ a surface restoring term to the k=1 salinity equation, thus imposing a salt flux onto the ocean even outside of sea ice regimes. This salt flux is non-physical, and represents a limitation of the ocean-ice models run without an interactive atmosphere. Sometimes this salt flux is converted to an implied fresh water flux. However, doing so generally leads to changes in the sea level, unless a global normalization is provided to zero-out the net water flux. As a complement, for models with a restoring salt flux, one may choose to zero-out the net salt entering the ocean. There are pros/cons of each approach. There are many terms that contribute to boundary-related heating of the k=1 surface model grid cell. We here outline details of this heat, with each term having units W/m2. The net flux of heat crossing ocean surface is stored in the diagnostic array "hfds". This array is computed as \[ \mbox{hfds = shortwave + longwave + latent + sensible + mass transfer + frazil + restore + flux adjustments} \] shortwave (SW) = shortwave radiation (always warms ocean) longwave (LW) = longwave radiation (generally cools ocean) latent (LAT) = turbulent latent heat loss due to evaporation (liquid to vapor) or melt (snow to liquid); generally cools the ocean sensible (SENS) = turbulent heat transfer due to differences in air-sea or ice-sea temperature mass transfer (MASS) = heat transfer due to heat content of mass (e.g., E-P+R) transferred across ocean surface; computed relative to 0 Celsius frazil (FRAZ) = heat transferred to form frazil sea ice (positive heating of liquid ocean) restore (RES) = heat from surface damping sometimes imposed in non-coupled model simulations . restore (flux adjustments) = heat from surface flux adjustment. The shortwave field itself is split into two pieces: shortwave = penetrative SW + non-penetrative SW non-penetrative = non-downwelling shortwave; portion of SW totally absorbed in the k=1 cell. The non-penetrative SW is combined with LW+LAT+SENS+seaice_melt_heat in net_heat inside routine extractFluxes1d. Notably, for many cases, non-penetrative SW = 0. penetrative = that portion of shortwave penetrating below a tiny surface layer. This is the downwelling shortwave. Penetrative SW participates in the penetrative SW heating of k=1,nz cells, with the amount of penetration dependent on optical properties. The convergence of boundary-related heat into surface grid cell is given by the difference in the net heat entering the top of the k=1 cell and the penetrative SW leaving the bottom of the cell. \begin{eqnarray*} Q(k=1) &=& \mbox{hfds} - \mbox{pen}\_\mbox{SW(leaving bottom of k=1)} \\ &=& \mbox{nonpen}\_\mbox{SW} + (\mbox{pen}\_\mbox{SW(enter k=1)}-\mbox{pen}\_\mbox{SW(leave k=1)}) + \mbox{LW+LAT+SENS+MASS+FRAZ+RES} \\ &=& \mbox{nonpen}\_\mbox{SW}+ \mbox{LW+LAT+SENS+MASS+FRAZ+RES} + [\mbox{pen}\_\mbox{SW(enter k=1)} - \mbox{pen}\_\mbox{SW(leave k=1)}] \end{eqnarray*} The convergence of the penetrative shortwave flux is given by $ \mbox{pen}\_\mbox{SW (enter k)}-\mbox{pen}\_\mbox{SW (leave k)}$. This term appears for all cells k=1,nz. It is diagnosed as "rsdoabsorb" inside module MOM6/src/parameterizations/vertical/MOM_diabatic_aux.F90