smooth lambda

interfaces/physics_schemes_interface/rose-meta/um-boundary_layer/HEAD/rose-meta.conf

@@ -257,15 +257,24 @@ help=Relax to SHARPEST: the stable stability function requested relaxes
     =above the BL top" is selected this option will also smoothly merge
     =to the asymptotic mixing length by 3km above the surface.
     =
-    =Corrected NTML is as the original but corrects the level
+    =Original with corrected NTML is as the original but corrects the level
     =(ntml_local) below which the boundary layer value is used.
-    =The final option extends this version to use interactively diagnosed
-    =turbulent layer depths throughout the atmospheric column.
+    =
+    =Original with diagnosed turbulent layer depths extends this version to
+    =use interactively diagnosed turbulent layer depths throughout the
+    =atmospheric column.
+    =
+    =Reduce smoothly towards layer boundaries calculates the lengthscale
+    =within each turbulent layer (including the surface layer) more smoothly,
+    =by interpolating between sub- and super- critical levels to find the
+    =base and top heights, and tapering the mixing length down near the base
+    =and top.
 ns=namelist/Science/UM Boundary layer
 sort-key=Panel-A05
 value-titles=Relax to SHARPEST,Original with corrected NTML,
-            =Original with diagnosed turbulent layer depths
-values='to_sharp','ntml_corrected','free_trop_layer'
+            =Original with diagnosed turbulent layer depths,
+            =Reduce smoothly towards layer boundaries
+values='to_sharp','ntml_corrected','free_trop_layer','smooth_to_boundaries'
 
 [namelist:blayer=fric_heating]
 compulsory=true

interfaces/physics_schemes_interface/source/support/um_physics_init_mod.f90

@@ -47,6 +47,7 @@ module um_physics_init_mod
                                         free_atm_mix, free_atm_mix_to_sharp,   &
                                         free_atm_mix_ntml_corrected,           &
                                         free_atm_mix_free_trop_layer,          &
+                                        free_atm_mix_smooth_to_boundaries,     &
                                         interp_local, interp_local_gradients,  &
                                         interp_local_cf_dbdz,                  &
                                         new_kcloudtop, p_unstable,             &
@@ -336,10 +337,11 @@ subroutine um_physics_init()
          DynDiag_ZL_corrn, blend_allpoints, ng_stress,                     &
          BrownGrant97_limited, BrownGrant97_original, lem_std,             &
          lem_adjust, interactive_fluxes, specified_fluxes_only,            &
-         except_disc_inv, ntml_level_corrn, free_trop_layers, sharpest,    &
-         lem_stability, sg_shear_enh_lambda, l_new_kcloudtop, buoy_integ,  &
-         l_reset_dec_thres, DynDiag_ZL_CuOnly, i_interp_local,             &
-         i_interp_local_gradients, l_noice_in_turb, l_use_var_fixes,       &
+         except_disc_inv, ntml_level_corrn, free_trop_layers,              &
+         smooth_to_bdys, sharpest, lem_stability, sg_shear_enh_lambda,     &
+         l_new_kcloudtop, buoy_integ, l_reset_dec_thres, DynDiag_ZL_CuOnly,&
+         i_interp_local, i_interp_local_gradients,                         &
+         l_noice_in_turb, l_use_var_fixes,                                 &
          i_interp_local_cf_dbdz, tke_diag_fac, a_ent_2, dec_thres_cloud,   &
          dec_thres_cu, near_neut_z_on_l, blend_gridindep_fa,               &
          specified_fluxes_tstar, buoy_integ_low, num_sweeps_bflux,         &
@@ -731,6 +733,8 @@ subroutine um_physics_init()
           local_fa = ntml_level_corrn
         case(free_atm_mix_free_trop_layer)
           local_fa = free_trop_layers
+        case(free_atm_mix_smooth_to_boundaries)
+          local_fa = smooth_to_bdys
       end select
 
       pstb = 2.0_r_um
@@ -765,9 +769,9 @@ subroutine um_physics_init()
           sg_orog_mixing = sg_shear_enh_lambda
       end select
 
-      ! Switch for corrections to variance diagnostics
-      l_use_var_fixes = .true.
+      ! TKE scaling parameter and switch for fixes to variance diagnostics
       tke_diag_fac  = 1.0_r_bl
+      l_use_var_fixes = .true.
       zhloc_depth_fac = real(zhloc_depth_fac_in, r_bl)
 
       if (topography == topography_horizon) then

rose-stem/app/lfric_atm/opt/rose-app-comorph_dev.conf

@@ -1,6 +1,7 @@
 [namelist:blayer]
 dzrad_disc_opt='smooth_1p5'
 entr_smooth_dec='taper_zh'
+free_atm_mix='smooth_to_boundaries'
 kprof_cu='buoy_integ_low'
 l_converge_ga=.true.
 l_use_sml_dsc_fixes=.true.

science/physics_schemes/source/boundary_layer/bdy_expl2.F90

@@ -82,7 +82,7 @@ subroutine bdy_expl2 (                                                         &
     nl_bl_levels, local_fa, free_trop_layers, to_sharp_across_1km,             &
     sbl_op, equilibrium_sbl, one_third, two_thirds, blending_option,           &
     blend_except_cu, blend_cth_shcu_only, sg_shear, sg_shear_enh_lambda,       &
-    max_tke, tke_diag_fac,                                                     &
+    max_tke, tke_diag_fac, smooth_to_bdys,                                     &
     i_interp_local, i_interp_local_gradients, i_interp_local_cf_dbdz,          &
     shallow_cu_maxtop, sc_cftol, near_neut_z_on_l, zero, one, one_half
 use cloud_inputs_mod, only: i_rhcpt, forced_cu, i_cld_vn, i_pc2_init_method,   &
@@ -670,6 +670,8 @@ subroutine bdy_expl2 (                                                         &
                               !  boundary layer (metres) as
                               !  determined from the local
                               !  Richardson number profile.
+zdsc_base(pdims%i_start:pdims%i_end,pdims%j_start:pdims%j_end),                &
+                              ! Height of base of K_top in DSC
 dsldz(tdims%i_start:tdims%i_end,tdims%j_start:tdims%j_end,                     &
       bl_levels),                                                              &
                               ! TL+gz/cp gradient between
@@ -945,7 +947,7 @@ subroutine bdy_expl2 (                                                         &
 ! heterogeneous land surface this is poorly defined and we can't use Rib
 ! from the surface scheme as vertically averaging Ri is numerically
 ! unstable.  So, over land, only the average temperature gradient is used
-if (.not. l_use_surf_in_ri) then
+if ( .not. l_use_surf_in_ri ) then
   ! if not using surface variables in Ri (l_use_surf_in_ri=false) we
   ! extrapolate dbdz itself from level 2, with the sl and qw gradients being
   ! used in the variance calculations and with i_interp_local_cf_dbdz
@@ -1859,7 +1861,7 @@ subroutine bdy_expl2 (                                                         &
     !     INOUT fields
              ftl,fqw,zhnl,dzh,cumulus,ntml_nl,w,etadot,t1_sd,q1_sd,wtrac_bl,   &
     !     out fields
-             rhokmz,rhokhz,rhokm_top,rhokh_top,zhsc,                           &
+             rhokmz,rhokhz,rhokm_top,rhokh_top,zhsc,zdsc_base,                 &
              unstable,dsc,coupled,sml_disc_inv,dsc_disc_inv,                   &
              ntdsc,nbdsc,f_ngstress,tke_nl,                                    &
              grad_t_adj, grad_q_adj,                                           &
@@ -1882,7 +1884,7 @@ subroutine bdy_expl2 (                                                         &
 !$OMP SHARED(pdims,unstable,fb_surf,cumulus,l_shallow,sml_disc_inv,ntpar,      &
 !$OMP        ntml_nl,zhnl,grad_t_adj,grad_q_adj,dsc,dsc_disc_inv,ntdsc,nbdsc,  &
 !$OMP        zhsc,dzh,coupled,kent,kent_dsc,t_frac,zrzi,we_lim,t_frac_dsc,     &
-!$OMP        zrzi_dsc,we_lim_dsc,kplume)
+!$OMP        zdsc_base,zrzi_dsc,we_lim_dsc,kplume)
 !$OMP do SCHEDULE(STATIC)
   do j = pdims%j_start, pdims%j_end
     do i = pdims%i_start, pdims%i_end
@@ -1903,6 +1905,7 @@ subroutine bdy_expl2 (                                                         &
       ntdsc(i,j)   = 0
       nbdsc(i,j)   = 0
       zhsc(i,j)    = zero
+      zdsc_base(i,j) = zero
       coupled(i,j) = .false.
       ! entrainment variables for non-local tracer mixing
       kent(i,j) = 2
@@ -1988,8 +1991,9 @@ subroutine bdy_expl2 (                                                         &
 ! in levels/logicals
    bl_levels,k_log_layr,BL_diag,                                               &
 ! in fields
-   sigma_h,flandg,dvdzm,ri,rho_wet_tq,z_uv,z_tq,z0m_eff_gb,zhpar,ntpar,        &
-   ntml_nl,ntdsc,nbdsc,l_shallow_cth,rmlmax2,rneutml_sq,delta_smag,            &
+   sigma_h,flandg,dvdzm,ri,rho_wet_tq,z_uv,z_tq,z0m_eff_gb,zhnl,zhpar,zhsc,    &
+   zdsc_base,ntpar,ntml_nl,ntdsc,nbdsc,l_shallow_cth,rmlmax2,rneutml_sq,       &
+   delta_smag,      &
 ! in/out fields
    cumulus,weight_1dbl,                                                        &
 ! out fields
@@ -2025,7 +2029,7 @@ subroutine bdy_expl2 (                                                         &
                             + (weight2/weight1)*weight_1dbl(i,j,k)
       end if
 
-      if (local_fa == free_trop_layers) then
+      if (local_fa == free_trop_layers .or. local_fa == smooth_to_bdys) then
         ! elh already included in rhokh_th so no need to calculate
         ! here, but interpolate elh separately for diagnostic
         if (BL_diag%l_elh3d) then
@@ -2076,7 +2080,7 @@ subroutine bdy_expl2 (                                                         &
           rhokh(i,j,k) = elh_rho(i,j,k) * rhokh(i,j,k)
 
         end if   ! test on sbl_op
-      end if   ! test on local_fa = free_trop_layers
+      end if   ! test on local_fa = free_trop_layers or smooth_to_bdys
 
           ! Finally multiply RHOKH by dry density
       if (l_mr_physics)                                                        &

science/physics_schemes/source/boundary_layer/bl_option_mod.F90

@@ -120,6 +120,10 @@ module bl_option_mod
 ! free_trop_layers (=3) => as "ntml_level_corrn" but also diagnose
 ! FA turbulent layer depths
 integer, parameter :: free_trop_layers    = 3
+! smooth_to_bdys (=4) => as "free_trop_layers" but smoothly interpolate
+! between sub- and super-critical model-levels to find depth of turbulent
+! layers, and taper the mixing-length down near top and bottom of each layer.
+integer, parameter :: smooth_to_bdys = 4
 
 ! 10 Switch to keep local mixing in free atmosphere
 integer :: Keep_Ri_FA = imdi