From c1aee46afa7b8c46b362c3c65895fcf69ae50025 Mon Sep 17 00:00:00 2001 From: Robert Hallberg Date: Thu, 8 Jun 2023 10:10:36 -0400 Subject: [PATCH] *Revise calc_isoneutral_slopes when non-Boussinesq Revise calc_isoneutral_slopes to eliminate any dependence on the Boussinesq reference density when in non-Boussinesq mode. This includes the addition of two new arrays to hold the rescaled product of the gravitational acceleration and the specific volume interpolated to the interfaces at velocity points. The answers change in non-Boussinesq mode when one of several parameterizations that use the isoneutral slopes are in use, but are bitwise identical in Boussinesq or semi-Boussinesq mode. --- src/core/MOM_isopycnal_slopes.F90 | 60 ++++++++++++++++++++++++++----- 1 file changed, 52 insertions(+), 8 deletions(-) diff --git a/src/core/MOM_isopycnal_slopes.F90 b/src/core/MOM_isopycnal_slopes.F90 index 29c547148d..5aa78cb87a 100644 --- a/src/core/MOM_isopycnal_slopes.F90 +++ b/src/core/MOM_isopycnal_slopes.F90 @@ -4,6 +4,7 @@ module MOM_isopycnal_slopes ! This file is part of MOM6. See LICENSE.md for the license. use MOM_debugging, only : hchksum, uvchksum +use MOM_error_handler, only : MOM_error, FATAL use MOM_grid, only : ocean_grid_type use MOM_unit_scaling, only : unit_scale_type use MOM_variables, only : thermo_var_ptrs @@ -81,10 +82,14 @@ subroutine calc_isoneutral_slopes(G, GV, US, h, e, tv, dt_kappa_smooth, use_stan real, dimension(SZIB_(G)) :: & T_u, & ! Temperature on the interface at the u-point [C ~> degC]. S_u, & ! Salinity on the interface at the u-point [S ~> ppt]. + GxSpV_u, & ! Gravitiational acceleration times the specific volume at an interface + ! at the u-points [L2 Z-1 T-2 R-1 ~> m4 s-2 kg-1] pres_u ! Pressure on the interface at the u-point [R L2 T-2 ~> Pa]. real, dimension(SZI_(G)) :: & T_v, & ! Temperature on the interface at the v-point [C ~> degC]. S_v, & ! Salinity on the interface at the v-point [S ~> ppt]. + GxSpV_v, & ! Gravitiational acceleration times the specific volume at an interface + ! at the v-points [L2 Z-1 T-2 R-1 ~> m4 s-2 kg-1] pres_v ! Pressure on the interface at the v-point [R L2 T-2 ~> Pa]. real, dimension(SZI_(G)) :: & T_h, & ! Temperature on the interface at the h-point [C ~> degC]. @@ -202,6 +207,17 @@ subroutine calc_isoneutral_slopes(G, GV, US, h, e, tv, dt_kappa_smooth, use_stan endif endif + if ((use_EOS .and. allocated(tv%SpV_avg) .and. (tv%valid_SpV_halo < 1)) .and. & + (present_N2_u .or. present(dzSxN) .or. present_N2_v .or. present(dzSyN))) then + if (tv%valid_SpV_halo < 0) then + call MOM_error(FATAL, "calc_isoneutral_slopes called in fully non-Boussinesq mode "//& + "with invalid values of SpV_avg.") + else + call MOM_error(FATAL, "calc_isoneutral_slopes called in fully non-Boussinesq mode "//& + "with insufficiently large SpV_avg halos of width 0 but 1 is needed.") + endif + endif + ! Find the maximum and minimum permitted streamfunction. if (associated(tv%p_surf)) then !$OMP parallel do default(shared) @@ -227,7 +243,7 @@ subroutine calc_isoneutral_slopes(G, GV, US, h, e, tv, dt_kappa_smooth, use_stan !$OMP local_open_u_BC,dzu,OBC,use_stanley) & !$OMP private(drdiA,drdiB,drdkL,drdkR,pres_u,T_u,S_u, & !$OMP drho_dT_u,drho_dS_u,hg2A,hg2B,hg2L,hg2R,haA, & - !$OMP drho_dT_dT_h,scrap,pres_h,T_h,S_h, & + !$OMP drho_dT_dT_h,scrap,pres_h,T_h,S_h,GxSpV_u, & !$OMP haB,haL,haR,dzaL,dzaR,wtA,wtB,wtL,wtR,drdz, & !$OMP drdx,mag_grad2,slope,l_seg) do j=js,je ; do K=nz,2,-1 @@ -245,6 +261,18 @@ subroutine calc_isoneutral_slopes(G, GV, US, h, e, tv, dt_kappa_smooth, use_stan enddo call calculate_density_derivs(T_u, S_u, pres_u, drho_dT_u, drho_dS_u, & tv%eqn_of_state, EOSdom_u) + if (present_N2_u .or. (present(dzSxN))) then + if (allocated(tv%SpV_avg)) then + do I=is-1,ie + GxSpV_u(I) = GV%g_Earth * 0.25* ((tv%SpV_avg(i,j,k) + tv%SpV_avg(i+1,j,k)) + & + (tv%SpV_avg(i,j,k-1) + tv%SpV_avg(i+1,j,k-1))) + enddo + else + do I=is-1,ie + GxSpV_u(I) = G_Rho0 + enddo + endif + endif endif if (use_stanley) then @@ -308,7 +336,9 @@ subroutine calc_isoneutral_slopes(G, GV, US, h, e, tv, dt_kappa_smooth, use_stan ! drdz = ((hg2L/haL) * drdkL/dzaL + (hg2R/haR) * drdkR/dzaR) / & ! ((hg2L/haL) + (hg2R/haR)) ! This is the gradient of density along geopotentials. - if (present_N2_u) N2_u(I,j,K) = G_Rho0 * drdz * G%mask2dCu(I,j) ! Square of buoyancy freq. [L2 Z-2 T-2 ~> s-2] + if (present_N2_u) then + N2_u(I,j,K) = GxSpV_u(I) * drdz * G%mask2dCu(I,j) ! Square of buoyancy freq. [L2 Z-2 T-2 ~> s-2] + endif if (use_EOS) then drdx = ((wtA * drdiA + wtB * drdiB) / (wtA + wtB) - & @@ -343,8 +373,8 @@ subroutine calc_isoneutral_slopes(G, GV, US, h, e, tv, dt_kappa_smooth, use_stan endif slope_x(I,j,K) = slope if (present(dzSxN)) & - dzSxN(I,j,K) = sqrt( G_Rho0 * max(0., wtL * ( dzaL * drdkL ) & - + wtR * ( dzaR * drdkR )) / (wtL + wtR) ) & ! dz * N + dzSxN(I,j,K) = sqrt( GxSpV_u(I) * max(0., wtL * ( dzaL * drdkL ) & + + wtR * ( dzaR * drdkR )) / (wtL + wtR) ) & ! dz * N * abs(slope) * G%mask2dCu(I,j) ! x-direction contribution to S^2 enddo ! I @@ -357,7 +387,7 @@ subroutine calc_isoneutral_slopes(G, GV, US, h, e, tv, dt_kappa_smooth, use_stan !$OMP dzv,local_open_v_BC,OBC,use_stanley) & !$OMP private(drdjA,drdjB,drdkL,drdkR,pres_v,T_v,S_v, & !$OMP drho_dT_v,drho_dS_v,hg2A,hg2B,hg2L,hg2R,haA, & - !$OMP drho_dT_dT_h,scrap,pres_h,T_h,S_h, & + !$OMP drho_dT_dT_h,scrap,pres_h,T_h,S_h,GxSpV_v, & !$OMP drho_dT_dT_hr,pres_hr,T_hr,S_hr, & !$OMP haB,haL,haR,dzaL,dzaR,wtA,wtB,wtL,wtR,drdz, & !$OMP drdy,mag_grad2,slope,l_seg) @@ -375,7 +405,21 @@ subroutine calc_isoneutral_slopes(G, GV, US, h, e, tv, dt_kappa_smooth, use_stan enddo call calculate_density_derivs(T_v, S_v, pres_v, drho_dT_v, drho_dS_v, & tv%eqn_of_state, EOSdom_v) + + if ((present_N2_v) .or. (present(dzSyN))) then + if (allocated(tv%SpV_avg)) then + do i=is,ie + GxSpV_v(i) = GV%g_Earth * 0.25* ((tv%SpV_avg(i,j,k) + tv%SpV_avg(i,j+1,k)) + & + (tv%SpV_avg(i,j,k-1) + tv%SpV_avg(i,j+1,k-1))) + enddo + else + do i=is,ie + GxSpV_v(i) = G_Rho0 + enddo + endif + endif endif + if (use_stanley) then do i=is,ie pres_h(i) = pres(i,j,K) @@ -443,7 +487,7 @@ subroutine calc_isoneutral_slopes(G, GV, US, h, e, tv, dt_kappa_smooth, use_stan ! drdz = ((hg2L/haL) * drdkL/dzaL + (hg2R/haR) * drdkR/dzaR) / & ! ((hg2L/haL) + (hg2R/haR)) ! This is the gradient of density along geopotentials. - if (present_N2_v) N2_v(i,J,K) = G_Rho0 * drdz * G%mask2dCv(i,J) ! Square of buoyancy freq. [L2 Z-2 T-2 ~> s-2] + if (present_N2_v) N2_v(i,J,K) = GxSpV_v(i) * drdz * G%mask2dCv(i,J) ! Square of buoyancy freq. [L2 Z-2 T-2 ~> s-2] if (use_EOS) then drdy = ((wtA * drdjA + wtB * drdjB) / (wtA + wtB) - & @@ -480,8 +524,8 @@ subroutine calc_isoneutral_slopes(G, GV, US, h, e, tv, dt_kappa_smooth, use_stan endif slope_y(i,J,K) = slope if (present(dzSyN)) & - dzSyN(i,J,K) = sqrt( G_Rho0 * max(0., wtL * ( dzaL * drdkL ) & - + wtR * ( dzaR * drdkR )) / (wtL + wtR) ) & ! dz * N + dzSyN(i,J,K) = sqrt( GxSpV_v(i) * max(0., wtL * ( dzaL * drdkL ) & + + wtR * ( dzaR * drdkR )) / (wtL + wtR) ) & ! dz * N * abs(slope) * G%mask2dCv(i,J) ! x-direction contribution to S^2 enddo ! i