From a1313aad99104b3690b871f8cc8c74409c0a3feb Mon Sep 17 00:00:00 2001 From: alex-huth Date: Wed, 23 Aug 2023 17:58:52 -0400 Subject: [PATCH] SSA convergence based on change of norm Added an option NONLIN_SOLVE_ERR_MODE=3 to check for convergence of the ice shelf SSA solution by testing the change of norm, i.e. 2*abs(|u_{t}|-|u_{t-1}|) / (|u_{t}|+|u_{t-1}|) --- src/ice_shelf/MOM_ice_shelf_dynamics.F90 | 70 +++++++++++++++++------- 1 file changed, 50 insertions(+), 20 deletions(-) diff --git a/src/ice_shelf/MOM_ice_shelf_dynamics.F90 b/src/ice_shelf/MOM_ice_shelf_dynamics.F90 index bb9de629f7..f4eacbb666 100644 --- a/src/ice_shelf/MOM_ice_shelf_dynamics.F90 +++ b/src/ice_shelf/MOM_ice_shelf_dynamics.F90 @@ -160,6 +160,7 @@ module MOM_ice_shelf_dynamics integer :: cg_max_iterations !< The maximum number of iterations that can be used in the CG solver integer :: nonlin_solve_err_mode !< 1: exit vel solve based on nonlin residual !! 2: exit based on "fixed point" metric (|u - u_last| / |u| < tol) where | | is infty-norm + !! 3: exit based on change of norm ! ids for outputting intermediate thickness in advection subroutine (debugging) !integer :: id_h_after_uflux = -1, id_h_after_vflux = -1, id_h_after_adv = -1 @@ -436,7 +437,7 @@ subroutine initialize_ice_shelf_dyn(param_file, Time, ISS, CS, G, US, diag, new_ units="m", default=1.e-3, scale=US%m_to_Z) call get_param(param_file, mdl, "NONLIN_SOLVE_ERR_MODE", CS%nonlin_solve_err_mode, & "Choose whether nonlin error in vel solve is based on nonlinear "//& - "residual (1) or relative change since last iteration (2)", default=1) + "residual (1), relative change since last iteration (2), or change in norm (3)", default=1) call get_param(param_file, mdl, "SHELF_MOVING_FRONT", CS%moving_shelf_front, & "Specify whether to advance shelf front (and calve).", & @@ -904,15 +905,17 @@ subroutine ice_shelf_solve_outer(CS, ISS, G, US, u_shlf, v_shlf, taudx, taudy, i real, dimension(SZDIB_(G),SZDJB_(G)) :: H_node ! Ice shelf thickness at corners [Z ~> m]. real, dimension(SZDI_(G),SZDJ_(G)) :: float_cond ! An array indicating where the ice ! shelf is floating: 0 if floating, 1 if not. + real, dimension(SZDIB_(G),SZDJB_(G)) :: Normvec ! Used for convergence character(len=160) :: mesg ! The text of an error message integer :: conv_flag, i, j, k,l, iter integer :: isdq, iedq, jsdq, jedq, isd, ied, jsd, jed, nodefloat, nsub - real :: err_max, err_tempu, err_tempv, err_init, max_vel, tempu, tempv + real :: err_max, err_tempu, err_tempv, err_init, max_vel, tempu, tempv, Norm, PrevNorm real :: rhoi_rhow ! The density of ice divided by a typical water density [nondim] real, pointer, dimension(:,:,:,:) :: Phi => NULL() ! The gradients of bilinear basis elements at Gaussian ! quadrature points surrounding the cell vertices [L-1 ~> m-1]. real, pointer, dimension(:,:,:,:,:,:) :: Phisub => NULL() ! Quadrature structure weights at subgridscale ! locations for finite element calculations [nondim] + integer :: Is_sum, Js_sum, Ie_sum, Je_sum ! Loop bounds for global sums or arrays starting at 1. ! for GL interpolation nsub = CS%n_sub_regularize @@ -993,17 +996,17 @@ subroutine ice_shelf_solve_outer(CS, ISS, G, US, u_shlf, v_shlf, taudx, taudy, i CS%basal_traction(i,j) = CS%basal_traction(i,j) * float_cond(i,j) enddo ; enddo + if (CS%nonlin_solve_err_mode == 1) then ! call apply_boundary_values(CS, ISS, G, US, time, Phisub, H_node, CS%ice_visc, & ! CS%basal_traction, float_cond, rhoi_rhow, u_bdry_cont, v_bdry_cont) - Au(:,:) = 0.0 ; Av(:,:) = 0.0 + Au(:,:) = 0.0 ; Av(:,:) = 0.0 - call CG_action(CS, Au, Av, u_shlf, v_shlf, Phi, Phisub, CS%umask, CS%vmask, ISS%hmask, H_node, & - CS%ice_visc, float_cond, CS%bed_elev, CS%basal_traction, & - G, US, G%isc-1, G%iec+1, G%jsc-1, G%jec+1, rhoi_rhow) - call pass_vector(Au, Av, G%domain, TO_ALL, BGRID_NE) + call CG_action(CS, Au, Av, u_shlf, v_shlf, Phi, Phisub, CS%umask, CS%vmask, ISS%hmask, H_node, & + CS%ice_visc, float_cond, CS%bed_elev, CS%basal_traction, & + G, US, G%isc-1, G%iec+1, G%jsc-1, G%jec+1, rhoi_rhow) + call pass_vector(Au, Av, G%domain, TO_ALL, BGRID_NE) - if (CS%nonlin_solve_err_mode == 1) then err_init = 0 ; err_tempu = 0 ; err_tempv = 0 do J=G%IscB,G%JecB ; do I=G%IscB,G%IecB if (CS%umask(I,J) == 1) then @@ -1019,6 +1022,24 @@ subroutine ice_shelf_solve_outer(CS, ISS, G, US, u_shlf, v_shlf, taudx, taudy, i enddo ; enddo call max_across_PEs(err_init) + elseif (CS%nonlin_solve_err_mode == 3) then + Normvec=0.0 + ! Determine the loop limits for sums, bearing in mind that the arrays will be starting at 1. + Is_sum = G%isc + (1-G%IsdB) + Ie_sum = G%iecB + (1-G%IsdB) + ! Include the edge if tile is at the western bdry; Should add a test to avoid this if reentrant. + if (G%isc+G%idg_offset==G%isg) Is_sum = G%IscB + (1-G%IsdB) + + Js_sum = G%jsc + (1-G%JsdB) + Je_sum = G%jecB + (1-G%JsdB) + ! Include the edge if tile is at the southern bdry; Should add a test to avoid this if reentrant. + if (G%jsc+G%jdg_offset==G%jsg) Js_sum = G%JscB + (1-G%JsdB) + do J=G%jscB,G%jecB ; do I=G%iscB,G%iecB + if (CS%umask(I,J) == 1) Normvec(I,J) = Normvec(I,J) + u_shlf(I,J)*u_shlf(I,J) + if (CS%vmask(I,J) == 1) Normvec(I,J) = Normvec(I,J) + v_shlf(I,J)*v_shlf(I,J) + enddo; enddo + Norm = reproducing_sum( Normvec, Is_sum, Ie_sum, Js_sum, Je_sum ) + Norm = sqrt(Norm) endif u_last(:,:) = u_shlf(:,:) ; v_last(:,:) = v_shlf(:,:) @@ -1051,22 +1072,21 @@ subroutine ice_shelf_solve_outer(CS, ISS, G, US, u_shlf, v_shlf, taudx, taudy, i CS%basal_traction(i,j) = CS%basal_traction(i,j) * float_cond(i,j) enddo ; enddo - !u_bdry_cont(:,:) = 0 ; v_bdry_cont(:,:) = 0 - - !call apply_boundary_values(CS, ISS, G, US, time, Phisub, H_node, CS%ice_visc, & - ! CS%basal_traction, float_cond, rhoi_rhow, u_bdry_cont, v_bdry_cont) + if (CS%nonlin_solve_err_mode == 1) then + !u_bdry_cont(:,:) = 0 ; v_bdry_cont(:,:) = 0 - Au(:,:) = 0 ; Av(:,:) = 0 + ! call apply_boundary_values(CS, ISS, G, US, time, Phisub, H_node, CS%ice_visc, & + ! CS%basal_traction, float_cond, rhoi_rhow, u_bdry_cont, v_bdry_cont) - call CG_action(CS, Au, Av, u_shlf, v_shlf, Phi, Phisub, CS%umask, CS%vmask, ISS%hmask, H_node, & - CS%ice_visc, float_cond, CS%bed_elev, CS%basal_traction, & - G, US, G%isc-1, G%iec+1, G%jsc-1, G%jec+1, rhoi_rhow) + Au(:,:) = 0 ; Av(:,:) = 0 - call pass_vector(Au, Av, G%domain, TO_ALL, BGRID_NE) + call CG_action(CS, Au, Av, u_shlf, v_shlf, Phi, Phisub, CS%umask, CS%vmask, ISS%hmask, H_node, & + CS%ice_visc, float_cond, CS%bed_elev, CS%basal_traction, & + G, US, G%isc-1, G%iec+1, G%jsc-1, G%jec+1, rhoi_rhow) - err_max = 0 + call pass_vector(Au, Av, G%domain, TO_ALL, BGRID_NE) - if (CS%nonlin_solve_err_mode == 1) then + err_max = 0 do J=G%jscB,G%jecB ; do I=G%jscB,G%iecB if (CS%umask(I,J) == 1) then @@ -1085,7 +1105,7 @@ subroutine ice_shelf_solve_outer(CS, ISS, G, US, u_shlf, v_shlf, taudx, taudy, i elseif (CS%nonlin_solve_err_mode == 2) then - max_vel = 0 ; tempu = 0 ; tempv = 0 + err_max=0. ; max_vel = 0 ; tempu = 0 ; tempv = 0 ; err_tempu = 0 do J=G%jscB,G%jecB ; do I=G%iscB,G%iecB if (CS%umask(I,J) == 1) then err_tempu = ABS(u_last(I,J)-u_shlf(I,J)) @@ -1108,6 +1128,16 @@ subroutine ice_shelf_solve_outer(CS, ISS, G, US, u_shlf, v_shlf, taudx, taudy, i call max_across_PEs(max_vel) call max_across_PEs(err_max) err_init = max_vel + + elseif (CS%nonlin_solve_err_mode == 3) then + PrevNorm=Norm; Norm=0.0; Normvec=0.0 + do J=G%jscB,G%jecB ; do I=G%iscB,G%iecB + if (CS%umask(I,J) == 1) Normvec(I,J) = Normvec(I,J) + u_shlf(I,J)*u_shlf(I,J) + if (CS%vmask(I,J) == 1) Normvec(I,J) = Normvec(I,J) + v_shlf(I,J)*v_shlf(I,J) + enddo; enddo + Norm = reproducing_sum( Normvec, Is_sum, Ie_sum, Js_sum, Je_sum ) + Norm = sqrt(Norm) + err_max=2.*abs(Norm-PrevNorm); err_init=Norm+PrevNorm endif write(mesg,*) "ice_shelf_solve_outer: nonlinear fractional residual = ", err_max/err_init