From 878fd1ef671456a804c598df606e4cf7c803c203 Mon Sep 17 00:00:00 2001 From: Robert Hallberg Date: Mon, 24 Jul 2023 14:14:29 -0400 Subject: [PATCH] +wave_speed arg mono_N2_depth in thickness units Changed the units of the optional mono_N2_depth argument to wave_speed, wave_speed_init and wave_speed_set_param in thickness units instead of height units. Accordingly, the units of one element each in the diagnostics_CS and wave_speed_CS and a local variable in VarMix_init are also changed to thickness units. The unit descriptions of some comments describing diagnostics were also amended to also describe the non-Boussinesq versions. Because this is essentially just changing when the unit conversion occurs, all answers are bitwise identical, but there are changes to the units of an optional argument in 3 publicly visible routines. --- src/diagnostics/MOM_diagnostics.F90 | 24 +++---- src/diagnostics/MOM_wave_speed.F90 | 64 ++++++++++--------- .../lateral/MOM_lateral_mixing_coeffs.F90 | 4 +- 3 files changed, 49 insertions(+), 43 deletions(-) diff --git a/src/diagnostics/MOM_diagnostics.F90 b/src/diagnostics/MOM_diagnostics.F90 index cf8b042c14..157c7268bf 100644 --- a/src/diagnostics/MOM_diagnostics.F90 +++ b/src/diagnostics/MOM_diagnostics.F90 @@ -56,7 +56,7 @@ module MOM_diagnostics !! monotonic for the purposes of calculating the equivalent !! barotropic wave speed [nondim]. real :: mono_N2_depth = -1. !< The depth below which N2 is limited as monotonic for the purposes of - !! calculating the equivalent barotropic wave speed [Z ~> m]. + !! calculating the equivalent barotropic wave speed [H ~> m or kg m-2]. type(diag_ctrl), pointer :: diag => NULL() !< A structure that is used to !! regulate the timing of diagnostic output. @@ -984,7 +984,7 @@ subroutine calculate_energy_diagnostics(u, v, h, uh, vh, ADp, CDp, G, GV, US, CS endif if (CS%id_dKEdt > 0) then - ! Calculate the time derivative of the layer KE [H L2 T-3 ~> m3 s-3]. + ! Calculate the time derivative of the layer KE [H L2 T-3 ~> m3 s-3 or W m-2]. do k=1,nz do j=js,je ; do I=Isq,Ieq KE_u(I,j) = uh(I,j,k) * G%dxCu(I,j) * CS%du_dt(I,j,k) @@ -1006,7 +1006,7 @@ subroutine calculate_energy_diagnostics(u, v, h, uh, vh, ADp, CDp, G, GV, US, CS endif if (CS%id_PE_to_KE > 0) then - ! Calculate the potential energy to KE term [H L2 T-3 ~> m3 s-3]. + ! Calculate the potential energy to KE term [H L2 T-3 ~> m3 s-3 or W m-2]. do k=1,nz do j=js,je ; do I=Isq,Ieq KE_u(I,j) = uh(I,j,k) * G%dxCu(I,j) * ADp%PFu(I,j,k) @@ -1025,7 +1025,7 @@ subroutine calculate_energy_diagnostics(u, v, h, uh, vh, ADp, CDp, G, GV, US, CS endif if (CS%id_KE_BT > 0) then - ! Calculate the barotropic contribution to KE term [H L2 T-3 ~> m3 s-3]. + ! Calculate the barotropic contribution to KE term [H L2 T-3 ~> m3 s-3 or W m-2]. do k=1,nz do j=js,je ; do I=Isq,Ieq KE_u(I,j) = uh(I,j,k) * G%dxCu(I,j) * ADp%u_accel_bt(I,j,k) @@ -1044,7 +1044,7 @@ subroutine calculate_energy_diagnostics(u, v, h, uh, vh, ADp, CDp, G, GV, US, CS endif if (CS%id_KE_Coradv > 0) then - ! Calculate the KE source from the combined Coriolis and advection terms [H L2 T-3 ~> m3 s-3]. + ! Calculate the KE source from the combined Coriolis and advection terms [H L2 T-3 ~> m3 s-3 or W m-2]. ! The Coriolis source should be zero, but is not due to truncation errors. There should be ! near-cancellation of the global integral of this spurious Coriolis source. do k=1,nz @@ -1069,7 +1069,7 @@ subroutine calculate_energy_diagnostics(u, v, h, uh, vh, ADp, CDp, G, GV, US, CS endif if (CS%id_KE_adv > 0) then - ! Calculate the KE source from along-layer advection [H L2 T-3 ~> m3 s-3]. + ! Calculate the KE source from along-layer advection [H L2 T-3 ~> m3 s-3 or W m-2]. ! NOTE: All terms in KE_adv are multiplied by -1, which can easily produce ! negative zeros and may signal a reproducibility issue over land. ! We resolve this by re-initializing and only evaluating over water points. @@ -1098,7 +1098,7 @@ subroutine calculate_energy_diagnostics(u, v, h, uh, vh, ADp, CDp, G, GV, US, CS endif if (CS%id_KE_visc > 0) then - ! Calculate the KE source from vertical viscosity [H L2 T-3 ~> m3 s-3]. + ! Calculate the KE source from vertical viscosity [H L2 T-3 ~> m3 s-3 or W m-2]. do k=1,nz do j=js,je ; do I=Isq,Ieq KE_u(I,j) = uh(I,j,k) * G%dxCu(I,j) * ADp%du_dt_visc(I,j,k) @@ -1117,7 +1117,7 @@ subroutine calculate_energy_diagnostics(u, v, h, uh, vh, ADp, CDp, G, GV, US, CS endif if (CS%id_KE_visc_gl90 > 0) then - ! Calculate the KE source from GL90 vertical viscosity [H L2 T-3 ~> m3 s-3]. + ! Calculate the KE source from GL90 vertical viscosity [H L2 T-3 ~> m3 s-3 or W m-2]. do k=1,nz do j=js,je ; do I=Isq,Ieq KE_u(I,j) = uh(I,j,k) * G%dxCu(I,j) * ADp%du_dt_visc_gl90(I,j,k) @@ -1136,7 +1136,7 @@ subroutine calculate_energy_diagnostics(u, v, h, uh, vh, ADp, CDp, G, GV, US, CS endif if (CS%id_KE_stress > 0) then - ! Calculate the KE source from surface stress (included in KE_visc) [H L2 T-3 ~> m3 s-3]. + ! Calculate the KE source from surface stress (included in KE_visc) [H L2 T-3 ~> m3 s-3 or W m-2]. do k=1,nz do j=js,je ; do I=Isq,Ieq KE_u(I,j) = uh(I,j,k) * G%dxCu(I,j) * ADp%du_dt_str(I,j,k) @@ -1155,7 +1155,7 @@ subroutine calculate_energy_diagnostics(u, v, h, uh, vh, ADp, CDp, G, GV, US, CS endif if (CS%id_KE_horvisc > 0) then - ! Calculate the KE source from horizontal viscosity [H L2 T-3 ~> m3 s-3]. + ! Calculate the KE source from horizontal viscosity [H L2 T-3 ~> m3 s-3 or W m-2]. do k=1,nz do j=js,je ; do I=Isq,Ieq KE_u(I,j) = uh(I,j,k) * G%dxCu(I,j) * ADp%diffu(I,j,k) @@ -1174,7 +1174,7 @@ subroutine calculate_energy_diagnostics(u, v, h, uh, vh, ADp, CDp, G, GV, US, CS endif if (CS%id_KE_dia > 0) then - ! Calculate the KE source from diapycnal diffusion [H L2 T-3 ~> m3 s-3]. + ! Calculate the KE source from diapycnal diffusion [H L2 T-3 ~> m3 s-3 or W m-2]. do k=1,nz do j=js,je ; do I=Isq,Ieq KE_u(I,j) = uh(I,j,k) * G%dxCu(I,j) * ADp%du_dt_dia(I,j,k) @@ -1594,7 +1594,7 @@ subroutine MOM_diagnostics_init(MIS, ADp, CDp, Time, G, GV, US, param_file, diag call get_param(param_file, mdl, "DIAG_EBT_MONO_N2_DEPTH", CS%mono_N2_depth, & "The depth below which N2 is limited as monotonic for the "// & "purposes of calculating the equivalent barotropic wave speed.", & - units='m', scale=US%m_to_Z, default=-1.) + units='m', scale=GV%m_to_H, default=-1.) call get_param(param_file, mdl, "INTERNAL_WAVE_SPEED_TOL", wave_speed_tol, & "The fractional tolerance for finding the wave speeds.", & units="nondim", default=0.001) diff --git a/src/diagnostics/MOM_wave_speed.F90 b/src/diagnostics/MOM_wave_speed.F90 index 5757e25cd1..c2b671f1c6 100644 --- a/src/diagnostics/MOM_wave_speed.F90 +++ b/src/diagnostics/MOM_wave_speed.F90 @@ -38,7 +38,7 @@ module MOM_wave_speed !! wave speed [nondim]. This parameter controls the default behavior of !! wave_speed() which can be overridden by optional arguments. real :: mono_N2_depth = -1. !< The depth below which N2 is limited as monotonic for the purposes of - !! calculating the equivalent barotropic wave speed [Z ~> m]. + !! calculating the equivalent barotropic wave speed [H ~> m or kg m-2]. !! If this parameter is negative, this limiting does not occur. !! This parameter controls the default behavior of wave_speed() which !! can be overridden by optional arguments. @@ -81,7 +81,7 @@ subroutine wave_speed(h, tv, G, GV, US, cg1, CS, full_halos, use_ebt_mode, mono_ !! for the purposes of calculating vertical modal structure [nondim]. real, optional, intent(in) :: mono_N2_depth !< A depth below which N2 is limited as !! monotonic for the purposes of calculating vertical - !! modal structure [Z ~> m]. + !! modal structure [H ~> m or kg m-2]. real, dimension(SZI_(G),SZJ_(G),SZK_(GV)), & optional, intent(out) :: modal_structure !< Normalized model structure [nondim] @@ -157,9 +157,11 @@ subroutine wave_speed(h, tv, G, GV, US, cg1, CS, full_halos, use_ebt_mode, mono_ real :: sum_hc ! The sum of the layer thicknesses [Z ~> m] real :: gp ! A limited local copy of gprime [L2 Z-1 T-2 ~> m s-2] real :: N2min ! A minimum buoyancy frequency, including a slope rescaling factor [L2 Z-2 T-2 ~> s-2] + logical :: below_mono_N2_frac ! True if an interface is below the fractional depth where N2 should not increase. + logical :: below_mono_N2_depth ! True if an interface is below the absolute depth where N2 should not increase. logical :: l_use_ebt_mode, calc_modal_structure real :: l_mono_N2_column_fraction ! A local value of mono_N2_column_fraction [nondim] - real :: l_mono_N2_depth ! A local value of mono_N2_column_depth [Z ~> m] + real :: l_mono_N2_depth ! A local value of mono_N2_column_depth [H ~> m or kg m-2] real :: mode_struct(SZK_(GV)) ! The mode structure [nondim], but it is also temporarily ! in units of [L2 T-2 ~> m2 s-2] after it is modified inside of tdma6. real :: ms_min, ms_max ! The minimum and maximum mode structure values returned from tdma6 [L2 T-2 ~> m2 s-2] @@ -214,18 +216,11 @@ subroutine wave_speed(h, tv, G, GV, US, cg1, CS, full_halos, use_ebt_mode, mono_ c2_scale = US%m_s_to_L_T**2 / 4096.0**2 ! Other powers of 2 give identical results. min_h_frac = tol_Hfrac / real(nz) -!$OMP parallel do default(none) shared(is,ie,js,je,nz,h,G,GV,US,min_h_frac,use_EOS,tv,& -!$OMP calc_modal_structure,l_use_ebt_mode,modal_structure, & -!$OMP l_mono_N2_column_fraction,l_mono_N2_depth,CS, & -!$OMP Z_to_pres,cg1,g_Rho0,rescale,I_rescale, & -!$OMP better_est,cg1_min2,tol_merge,tol_solve,c2_scale) & -!$OMP private(htot,hmin,kf,H_here,HxT_here,HxS_here,HxR_here, & -!$OMP Hf,Tf,Sf,Rf,pres,T_int,S_int,drho_dT,drho_dS, & -!$OMP drxh_sum,kc,Hc,Hc_H,Tc,Sc,I_Hnew,gprime,& -!$OMP Rc,speed2_tot,Igl,Igu,lam0,lam,lam_it,dlam, & -!$OMP mode_struct,sum_hc,N2min,gp,hw, & -!$OMP ms_min,ms_max,ms_sq,H_top,H_bot,I_Htot,merge, & -!$OMP det,ddet,det_it,ddet_it) + !$OMP parallel do default(private) shared(is,ie,js,je,nz,h,G,GV,US,tv,use_EOS, & + !$OMP CS,min_h_frac,calc_modal_structure,l_use_ebt_mode, & + !$OMP modal_structure,l_mono_N2_column_fraction,l_mono_N2_depth, & + !$OMP Z_to_pres,cg1,g_Rho0,rescale,I_rescale,cg1_min2, & + !$OMP better_est,tol_solve,tol_merge,c2_scale) do j=js,je ! First merge very thin layers with the one above (or below if they are ! at the top). This also transposes the row order so that columns can @@ -335,7 +330,7 @@ subroutine wave_speed(h, tv, G, GV, US, cg1, CS, full_halos, use_ebt_mode, mono_ drxh_sum = drxh_sum + 0.5*(Hf(k-1,i)+Hf(k,i)) * max(0.0,Rf(k,i)-Rf(k-1,i)) enddo endif - endif + endif ! use_EOS ! Find gprime across each internal interface, taking care of convective instabilities by ! merging layers. If the estimated wave speed is too small, simply return zero. @@ -452,24 +447,34 @@ subroutine wave_speed(h, tv, G, GV, US, cg1, CS, full_halos, use_ebt_mode, mono_ Igu(1) = 0. ! Neumann condition for pressure modes sum_hc = Hc(1) N2min = gprime(2)/Hc(1) + + below_mono_N2_frac = .false. + below_mono_N2_depth = .false. do k=2,kc hw = 0.5*(Hc(k-1)+Hc(k)) gp = gprime(K) if (l_mono_N2_column_fraction>0. .or. l_mono_N2_depth>=0.) then - !### Change to: if ( ((htot(i) - sum_hc < l_mono_N2_column_fraction*htot(i)) .or. & ) ) - if ( (((G%bathyT(i,j)+G%Z_ref) - sum_hc < l_mono_N2_column_fraction*(G%bathyT(i,j)+G%Z_ref)) .or. & - ((l_mono_N2_depth >= 0.) .and. (sum_hc > l_mono_N2_depth))) .and. & - (gp > N2min*hw) ) then - ! Filters out regions where N2 increases with depth but only in a lower fraction + ! Determine whether N2 estimates should not be allowed to increase with depth. + if (l_mono_N2_column_fraction>0.) then + !### Change to: (htot(i) - sum_hc < l_mono_N2_column_fraction*htot(i)) + below_mono_N2_frac = ((G%bathyT(i,j)+G%Z_ref) - GV%H_to_Z*sum_hc < & + l_mono_N2_column_fraction*(G%bathyT(i,j)+G%Z_ref)) + endif + if (l_mono_N2_depth >= 0.) below_mono_N2_depth = (sum_hc > GV%H_to_Z*l_mono_N2_depth) + + if ( (gp > N2min*hw) .and. (below_mono_N2_frac .or. below_mono_N2_depth) ) then + ! Filters out regions where N2 increases with depth, but only in a lower fraction ! of the water column or below a certain depth. gp = N2min * hw else N2min = gp / hw endif endif + Igu(k) = 1.0/(gp*Hc(k)) Igl(k-1) = 1.0/(gp*Hc(k-1)) sum_hc = sum_hc + Hc(k) + if (better_est) then ! Estimate that the ebt_mode is sqrt(2) times the speed of the flat bottom modes. speed2_tot = speed2_tot + 2.0 * gprime(K)*((H_top(K) * H_bot(K)) * I_Htot) @@ -690,7 +695,7 @@ subroutine wave_speeds(h, tv, G, GV, US, nmodes, cn, CS, w_struct, u_struct, u_s H_top, & ! The distance of each filtered interface from the ocean surface [Z ~> m] H_bot, & ! The distance of each filtered interface from the bottom [Z ~> m] gprime, & ! The reduced gravity across each interface [L2 Z-1 T-2 ~> m s-2]. - N2 ! The Brunt Vaissalla freqency squared [T-2 ~> s-2] + N2 ! The buoyancy freqency squared [T-2 ~> s-2] real, dimension(SZK_(GV),SZI_(G)) :: & Hf, & ! Layer thicknesses after very thin layers are combined [Z ~> m] Tf, & ! Layer temperatures after very thin layers are combined [C ~> degC] @@ -704,7 +709,7 @@ subroutine wave_speeds(h, tv, G, GV, US, nmodes, cn, CS, w_struct, u_struct, u_s Sc, & ! A column of layer salinities after convective instabilities are removed [S ~> ppt] Rc, & ! A column of layer densities after convective instabilities are removed [R ~> kg m-3] Hc_H ! Hc(:) rescaled from Z to thickness units [H ~> m or kg m-2] - real :: I_Htot ! The inverse of the total filtered thicknesses [Z ~> m] + real :: I_Htot ! The inverse of the total filtered thicknesses [Z-1 ~> m-1] real :: c2_scale ! A scaling factor for wave speeds to help control the growth of the determinant and its ! derivative with lam between rows of the Thomas algorithm solver [L2 s2 T-2 m-2 ~> nondim]. ! The exact value should not matter for the final result if it is an even power of 2. @@ -797,6 +802,7 @@ subroutine wave_speeds(h, tv, G, GV, US, nmodes, cn, CS, w_struct, u_struct, u_s ! Simplifying the following could change answers at roundoff. Z_to_pres = GV%Z_to_H * (GV%H_to_RZ * GV%g_Earth) use_EOS = associated(tv%eqn_of_state) + if (CS%c1_thresh < 0.0) & call MOM_error(FATAL, "INTERNAL_WAVE_CG1_THRESH must be set to a non-negative "//& "value via wave_speed_init for wave_speeds to be used.") @@ -978,7 +984,7 @@ subroutine wave_speeds(h, tv, G, GV, US, nmodes, cn, CS, w_struct, u_struct, u_s I_Hnew = 1.0 / (Hc(kc) + Hc(kc-1)) Tc(kc-1) = (Hc(kc)*Tc(kc) + Hc(kc-1)*Tc(kc-1)) * I_Hnew Sc(kc-1) = (Hc(kc)*Sc(kc) + Hc(kc-1)*Sc(kc-1)) * I_Hnew - Hc(kc-1) = (Hc(kc) + Hc(kc-1)) + Hc(kc-1) = Hc(kc) + Hc(kc-1) kc = kc - 1 else ; exit ; endif enddo @@ -1006,7 +1012,7 @@ subroutine wave_speeds(h, tv, G, GV, US, nmodes, cn, CS, w_struct, u_struct, u_s if (merge) then ! Merge this layer with the one above and backtrack. Rc(kc) = (Hc(kc)*Rc(kc) + Hf(k,i)*Rf(k,i)) / (Hc(kc) + Hf(k,i)) - Hc(kc) = (Hc(kc) + Hf(k,i)) + Hc(kc) = Hc(kc) + Hf(k,i) ! Backtrack to remove any convective instabilities above... Note ! that the tolerance is a factor of two larger, to avoid limit how ! far back we go. @@ -1019,7 +1025,7 @@ subroutine wave_speeds(h, tv, G, GV, US, nmodes, cn, CS, w_struct, u_struct, u_s if (merge) then ! Merge the two bottommost layers. At this point kc = k2. Rc(kc-1) = (Hc(kc)*Rc(kc) + Hc(kc-1)*Rc(kc-1)) / (Hc(kc) + Hc(kc-1)) - Hc(kc-1) = (Hc(kc) + Hc(kc-1)) + Hc(kc-1) = Hc(kc) + Hc(kc-1) kc = kc - 1 else ; exit ; endif enddo @@ -1109,7 +1115,7 @@ subroutine wave_speeds(h, tv, G, GV, US, nmodes, cn, CS, w_struct, u_struct, u_s do k=1,kc w2avg = w2avg + 0.5*(mode_struct(K)**2+mode_struct(K+1)**2)*Hc(k) ![Z L4 T-4] enddo - renorm = sqrt(htot(i)*a_int/w2avg) ![L-2 T-2] + renorm = sqrt(htot(i)*a_int/w2avg) ! [T2 L-2] do K=1,kc+1 ; mode_struct(K) = renorm * mode_struct(K) ; enddo ! after renorm, mode_struct is again [nondim] @@ -1437,7 +1443,7 @@ subroutine wave_speed_init(CS, use_ebt_mode, mono_N2_column_fraction, mono_N2_de !! calculating the vertical modal structure [nondim]. real, optional, intent(in) :: mono_N2_depth !< The depth below which N2 is limited !! as monotonic for the purposes of calculating the - !! vertical modal structure [Z ~> m]. + !! vertical modal structure [H ~> m or kg m-2]. logical, optional, intent(in) :: remap_answers_2018 !< If true, use the order of arithmetic and expressions !! that recover the remapping answers from 2018. Otherwise !! use more robust but mathematically equivalent expressions. @@ -1489,7 +1495,7 @@ subroutine wave_speed_set_param(CS, use_ebt_mode, mono_N2_column_fraction, mono_ !! calculating the vertical modal structure [nondim]. real, optional, intent(in) :: mono_N2_depth !< The depth below which N2 is limited !! as monotonic for the purposes of calculating the - !! vertical modal structure [Z ~> m]. + !! vertical modal structure [H ~> m or kg m-2]. logical, optional, intent(in) :: remap_answers_2018 !< If true, use the order of arithmetic and expressions !! that recover the remapping answers from 2018. Otherwise !! use more robust but mathematically equivalent expressions. diff --git a/src/parameterizations/lateral/MOM_lateral_mixing_coeffs.F90 b/src/parameterizations/lateral/MOM_lateral_mixing_coeffs.F90 index e74e48055a..df26f3f6a4 100644 --- a/src/parameterizations/lateral/MOM_lateral_mixing_coeffs.F90 +++ b/src/parameterizations/lateral/MOM_lateral_mixing_coeffs.F90 @@ -1103,7 +1103,7 @@ subroutine VarMix_init(Time, G, GV, US, param_file, diag, CS) real :: oneOrTwo ! A variable that may be 1 or 2, depending on which form ! of the equatorial deformation radius us used [nondim] real :: N2_filter_depth ! A depth below which stratification is treated as monotonic when - ! calculating the first-mode wave speed [Z ~> m] + ! calculating the first-mode wave speed [H ~> m or kg m-2] real :: KhTr_passivity_coeff ! Coefficient setting the ratio between along-isopycnal tracer ! mixing and interface height mixing [nondim] real :: absurdly_small_freq ! A miniscule frequency that is used to avoid division by 0 [T-1 ~> s-1]. The @@ -1241,7 +1241,7 @@ subroutine VarMix_init(Time, G, GV, US, param_file, diag, CS) "The depth below which N2 is monotonized to avoid stratification "//& "artifacts from altering the equivalent barotropic mode structure. "//& "This monotonzization is disabled if this parameter is negative.", & - units="m", default=-1.0, scale=US%m_to_Z) + units="m", default=-1.0, scale=GV%m_to_H) allocate(CS%ebt_struct(isd:ied,jsd:jed,GV%ke), source=0.0) endif