Release FV3 solver updates (NOAA-EMC#261)

* Bringing over internal updates to nh_core and nh_utils which includes a revision to the semi-implicit solver to linearize vertical sound wave propagation about the hydrostatic state.

* resolve inconsistent use of single and double precision in rayleigh damping.  Address spacing change.

* rename tau_w

* Modify the rff calculation to be fully double precision.  Fixed a mistake in the previous cherry-pick commit

* fully implement the name change of tau_w to fast_tau_w_sec

model/dyn_core.F90

@@ -632,7 +632,8 @@ subroutine dyn_core(npx, npy, npz, ng, sphum, nq, bdt, n_map, n_split, zvir, cp,
 #endif
                                ptop, phis, omga, ptc,  &
                                q_con,  delpc, gz,  pkc, ws3, flagstruct%p_fac, &
-                                flagstruct%a_imp, flagstruct%scale_z )
+                               flagstruct%a_imp, flagstruct%scale_z, pfull, &
+                               flagstruct%fast_tau_w_sec, flagstruct%rf_cutoff )
                                                call timing_off('Riem_Solver')
 
            if (gridstruct%nested) then
@@ -1050,7 +1051,8 @@ subroutine dyn_core(npx, npy, npz, ng, sphum, nq, bdt, n_map, n_split, zvir, cp,
                          ptop, zs, q_con, w, delz, pt, delp, zh,   &
                          pe, pkc, pk3, pk, peln, ws, &
                          flagstruct%scale_z, flagstruct%p_fac, flagstruct%a_imp, &
-                         flagstruct%use_logp, remap_step, beta<-0.1)
+                         flagstruct%use_logp, remap_step, beta<-0.1, &
+                         flagstruct%fast_tau_w_sec)
                                                          call timing_off('Riem_Solver')
 
                                        call timing_on('COMM_TOTAL')

model/fv_arrays.F90

@@ -698,6 +698,9 @@ module fv_arrays_mod
                          !< considered; and for non-hydrostatic models values of 10 or less should be
                          !< considered, with smaller values for higher-resolution.
    real    :: rf_cutoff = 30.E2   !< Pressure below which no Rayleigh damping is applied if tau > 0.
+   real    :: fast_tau_w_sec = 0.0 !< Time scale (seconds) for Rayleigh damping applied to vertical velocity only.
+                                   !< Values of 0.2 are very effective at eliminating spurious vertical motion in
+                                   !< the stratosphere. Default is 0.0, which disables this.
    logical :: filter_phys = .false.
    logical :: dwind_2d = .false.   !< Whether to use a simpler & faster algorithm for interpolating
                                    !< the A-grid (cell-centered) wind tendencies computed from the physics

model/fv_control.F90

@@ -331,6 +331,7 @@ subroutine fv_control_init(Atm, dt_atmos, this_grid, grids_on_this_pe, p_split,
      real    , pointer :: consv_te
      real    , pointer :: tau
      real    , pointer :: tau_w
+     real    , pointer :: fast_tau_w_sec
      real    , pointer :: rf_cutoff
      logical , pointer :: filter_phys
      logical , pointer :: dwind_2d
@@ -887,6 +888,7 @@ subroutine set_namelist_pointers(Atm)
        consv_te                      => Atm%flagstruct%consv_te
        tau                           => Atm%flagstruct%tau
        tau_w                         => Atm%flagstruct%tau_w
+       fast_tau_w_sec                => Atm%flagstruct%fast_tau_w_sec
        rf_cutoff                     => Atm%flagstruct%rf_cutoff
        filter_phys                   => Atm%flagstruct%filter_phys
        dwind_2d                      => Atm%flagstruct%dwind_2d
@@ -1055,7 +1057,7 @@ subroutine read_namelist_fv_core_nml(Atm)
             dry_mass, grid_type, do_Held_Suarez, do_reed_physics, reed_cond_only, &
             consv_te, fill, filter_phys, fill_dp, fill_wz, fill_gfs, consv_am, RF_fast, &
             range_warn, dwind_2d, inline_q, z_tracer, reproduce_sum, adiabatic, do_vort_damp, no_dycore,   &
-            tau, tau_w, tau_h2o, rf_cutoff, nf_omega, hydrostatic, fv_sg_adj, sg_cutoff, breed_vortex_inline,  &
+            tau, tau_w, fast_tau_w_sec, tau_h2o, rf_cutoff, nf_omega, hydrostatic, fv_sg_adj, sg_cutoff, breed_vortex_inline,  &
             na_init, nudge_dz, hybrid_z, Make_NH, n_zs_filter, nord_zs_filter, full_zs_filter, reset_eta,         &
             pnats, dnats, dnrts, a2b_ord, remap_t, p_ref, d2_bg_k1, d2_bg_k2,  &
             c2l_ord, dx_const, dy_const, umax, deglat,      &

model/nh_core.F90

@@ -72,7 +72,7 @@ subroutine Riem_Solver3(ms, dt,   is,   ie,   js, je, km, ng,    &
                           ptop, zs, q_con, w,  delz, pt,  &
                           delp, zh, pe, ppe, pk3, pk, peln, &
                           ws, scale_m,  p_fac, a_imp, &
-                          use_logp, last_call, fp_out)
+                          use_logp, last_call, fp_out, fast_tau_w_sec)
 !--------------------------------------------
 ! !OUTPUT PARAMETERS
 ! Ouput: gz: grav*height at edges
@@ -82,7 +82,7 @@ subroutine Riem_Solver3(ms, dt,   is,   ie,   js, je, km, ng,    &
    integer, intent(in):: ms, is, ie, js, je, km, ng
    integer, intent(in):: isd, ied, jsd, jed
    real, intent(in):: dt         !< the BIG horizontal Lagrangian time step
-   real, intent(in):: akap, cp, ptop, p_fac, a_imp, scale_m
+   real, intent(in):: akap, cp, ptop, p_fac, a_imp, scale_m, fast_tau_w_sec
    real, intent(in):: zs(isd:ied,jsd:jed)
    logical, intent(in):: last_call, use_logp, fp_out
    real, intent(in):: ws(is:ie,js:je)
@@ -116,10 +116,10 @@ subroutine Riem_Solver3(ms, dt,   is,   ie,   js, je, km, ng,    &
 !$OMP parallel do default(none) shared(is,ie,js,je,km,delp,ptop,peln1,pk3,ptk,akap,rgrav,zh,pt, &
 !$OMP                                  w,a_imp,dt,gama,ws,p_fac,scale_m,ms,delz,last_call,  &
 #ifdef MULTI_GASES
-!$OMP                                  peln,pk,fp_out,ppe,use_logp,zs,pe,cappa,q_con,kapad )          &
+!$OMP                                  peln,pk,fp_out,ppe,use_logp,zs,pe,cappa,q_con,kapad,fast_tau_w_sec )          &
 !$OMP                          private(cp2, gm2, dm, dz2, pm2, pem, peg, pelng, pe2, peln2, w2,kapad2)
 #else
-!$OMP                                  peln,pk,fp_out,ppe,use_logp,zs,pe,cappa,q_con )          &
+!$OMP                                  peln,pk,fp_out,ppe,use_logp,zs,pe,cappa,q_con,fast_tau_w_sec )     &
 !$OMP                          private(cp2, gm2, dm, dz2, pm2, pem, peg, pelng, pe2, peln2, w2)
 #endif
    do 2000 j=js, je
@@ -206,15 +206,15 @@ subroutine Riem_Solver3(ms, dt,   is,   ie,   js, je, km, ng,    &
                             kapad2,  &
 #endif
                             pe2, dm,   &
-                            pm2, pem, w2, dz2, pt(is:ie,j,1:km), ws(is,j), p_fac)
+                            pm2, pem, w2, dz2, pt(is:ie,j,1:km), ws(is,j), p_fac, fast_tau_w_sec)
       else
            call SIM_solver(dt, is, ie, km, rdgas, gama, gm2, cp2, akap, &
 #ifdef MULTI_GASES
                            kapad2,  &
 #endif
                            pe2, dm,  &
                            pm2, pem, w2, dz2, pt(is:ie,j,1:km), ws(is,j), &
-                           a_imp, p_fac, scale_m)
+                           a_imp, p_fac, scale_m, fast_tau_w_sec)
       endif
 
 

model/nh_utils.F90

@@ -54,9 +54,11 @@ module nh_utils_mod
 #else
    use constants_mod,     only: rdgas, cp_air, grav
 #endif
+   use constants_mod,     only: pi_8
    use tp_core_mod,       only: fv_tp_2d
    use sw_core_mod,       only: fill_4corners, del6_vt_flux
    use fv_arrays_mod,     only: fv_grid_bounds_type, fv_grid_type,fv_nest_BC_type_3d
+   use mpp_mod,           only: mpp_pe
 #ifdef MULTI_GASES
    use multi_gases_mod,  only:  vicpqd, vicvqd
 #endif
@@ -71,6 +73,10 @@ module nh_utils_mod
 
    real, parameter:: r3 = 1./3.
 
+   real, allocatable :: rff(:)
+   logical :: RFw_initialized = .false.
+   integer :: k_rf = 0
+
 CONTAINS
 
   subroutine update_dz_c(is, ie, js, je, km, ng, dt, dp0, zs, area, ut, vt, gz, ws, &
@@ -346,11 +352,12 @@ subroutine Riem_Solver_c(ms,   dt,  is,   ie,   js, je, km,   ng,  &
                            kapad, &
 #endif
                            ptop, hs, w3,  pt, q_con, &
-                           delp, gz,  pef,  ws, p_fac, a_imp, scale_m)
+                           delp, gz,  pef,  ws, p_fac, a_imp, scale_m, &
+                           pfull, fast_tau_w_sec, rf_cutoff)
 
    integer, intent(in):: is, ie, js, je, ng, km
    integer, intent(in):: ms
-   real, intent(in):: dt,  akap, cp, ptop, p_fac, a_imp, scale_m
+   real, intent(in):: dt,  akap, cp, ptop, p_fac, a_imp, scale_m, fast_tau_w_sec, rf_cutoff
    real, intent(in):: ws(is-ng:ie+ng,js-ng:je+ng)
    real, intent(in), dimension(is-ng:ie+ng,js-ng:je+ng,km):: pt, delp
    real, intent(in), dimension(is-ng:,js-ng:,1:):: q_con, cappa
@@ -359,6 +366,7 @@ subroutine Riem_Solver_c(ms,   dt,  is,   ie,   js, je, km,   ng,  &
 #endif
    real, intent(in)::   hs(is-ng:ie+ng,js-ng:je+ng)
    real, intent(in), dimension(is-ng:ie+ng,js-ng:je+ng,km):: w3
+   real, intent(in) :: pfull(km)
 ! OUTPUT PARAMETERS
    real, intent(inout), dimension(is-ng:ie+ng,js-ng:je+ng,km+1):: gz
    real, intent(  out), dimension(is-ng:ie+ng,js-ng:je+ng,km+1):: pef
@@ -369,6 +377,7 @@ subroutine Riem_Solver_c(ms,   dt,  is,   ie,   js, je, km,   ng,  &
   real, dimension(is-1:ie+1,km  ):: kapad2
 #endif
   real gama, rgrav
+  real(kind=8) :: rff_temp
   integer i, j, k
   integer is1, ie1
 
@@ -378,12 +387,26 @@ subroutine Riem_Solver_c(ms,   dt,  is,   ie,   js, je, km,   ng,  &
    is1 = is - 1
    ie1 = ie + 1
 
+   !Set up rayleigh damping
+   if (fast_tau_w_sec > 1.e-5 .and. .not. RFw_initialized) then
+      allocate(rff(km))
+      RFw_initialized = .true.
+      do k=1,km
+         if (pfull(k) > rf_cutoff) exit
+         k_rf = k
+         rff_temp = real(dt/fast_tau_w_sec,kind=8) &
+                  * sin(0.5d0*pi_8*log(real(rf_cutoff/pfull(k),kind=8))/log(real(rf_cutoff/ptop, kind=8)))**2
+         rff(k) = 1.0d0 / ( 1.0d0+rff_temp )
+      enddo
+   endif
+
+
 !$OMP parallel do default(none) shared(js,je,is1,ie1,km,delp,pef,ptop,gz,rgrav,w3,pt, &
 #ifdef MULTI_GASES
 !$OMP                                  a_imp,dt,gama,akap,ws,p_fac,scale_m,ms,hs,q_con,cappa,kapad) &
 !$OMP                          private(cp2,gm2, dm, dz2, w2, pm2, pe2, pem, peg, kapad2)
 #else
-!$OMP                                  a_imp,dt,gama,akap,ws,p_fac,scale_m,ms,hs,q_con,cappa) &
+!$OMP                                  a_imp,dt,gama,akap,ws,p_fac,scale_m,ms,hs,q_con,cappa,fast_tau_w_sec) &
 !$OMP                          private(cp2,gm2, dm, dz2, w2, pm2, pe2, pem, peg)
 #endif
    do 2000 j=js-1, je+1
@@ -455,7 +478,7 @@ subroutine Riem_Solver_c(ms,   dt,  is,   ie,   js, je, km,   ng,  &
                             kapad2, &
 #endif
                             pe2,  &
-                            dm, pm2, pem, w2, dz2, pt(is1:ie1,j,1:km), ws(is1,j), p_fac)
+                            dm, pm2, pem, w2, dz2, pt(is1:ie1,j,1:km), ws(is1,j), p_fac, fast_tau_w_sec)
       endif
 
       do k=2,km+1
@@ -622,15 +645,15 @@ subroutine Riem_Solver3test(ms, dt,   is,   ie,   js, je, km, ng,    &
                             kapad2, &
 #endif
                             pe2, dm,   &
-                            pm2, pem, w2, dz2, pt(is:ie,j,1:km), ws(is,j), p_fac)
+                            pm2, pem, w2, dz2, pt(is:ie,j,1:km), ws(is,j), p_fac, -1.)
       else
            call SIM_solver(dt, is, ie, km, rdgas, gama, gm2, cp2, akap, &
 #ifdef MULTI_GASES
                            kapad2, &
 #endif
                            pe2, dm,  &
                            pm2, pem, w2, dz2, pt(is:ie,j,1:km), ws(is,j), &
-                           a_imp, p_fac, scale_m)
+                           a_imp, p_fac, scale_m, -1.)
       endif
 
       do k=1, km
@@ -1385,9 +1408,9 @@ subroutine SIM1_solver(dt,  is,  ie, km, rgas, gama, gm2, cp2, kappa, &
                         kapad2, &
 #endif
                         pe, dm2,   &
-                        pm2, pem, w2, dz2, pt2, ws, p_fac)
+                        pm2, pem, w2, dz2, pt2, ws, p_fac, fast_tau_w_sec)
    integer, intent(in):: is, ie, km
-   real,    intent(in):: dt, rgas, gama, kappa, p_fac
+   real,    intent(in):: dt, rgas, gama, kappa, p_fac, fast_tau_w_sec
    real, intent(in), dimension(is:ie,km):: dm2, pt2, pm2, gm2, cp2
    real, intent(in )::  ws(is:ie)
    real, intent(in ), dimension(is:ie,km+1):: pem
@@ -1464,14 +1487,14 @@ subroutine SIM1_solver(dt,  is,  ie, km, rgas, gama, gm2, cp2, kappa, &
     do k=2, km
        do i=is, ie
 #ifdef MOIST_CAPPA
-          aa(i,k) = t1g*0.5*(gm2(i,k-1)+gm2(i,k))/(dz2(i,k-1)+dz2(i,k)) * (pem(i,k)+pp(i,k))
+          aa(i,k) = t1g*0.5*(gm2(i,k-1)+gm2(i,k))/(dz2(i,k-1)+dz2(i,k)) * (pem(i,k))
 #else
 #ifdef MULTI_GASES
           gamax = 1./(1.-kapad2(i,k))
           t1gx = gamax * 2.*dt*dt
-          aa(i,k) = t1gx/(dz2(i,k-1)+dz2(i,k)) * (pem(i,k)+pp(i,k))
+          aa(i,k) = t1gx/(dz2(i,k-1)+dz2(i,k)) * (pem(i,k))
 #else
-          aa(i,k) = t1g/(dz2(i,k-1)+dz2(i,k)) * (pem(i,k)+pp(i,k))
+          aa(i,k) = t1g/(dz2(i,k-1)+dz2(i,k)) * (pem(i,k))
 #endif
 #endif
        enddo
@@ -1489,14 +1512,14 @@ subroutine SIM1_solver(dt,  is,  ie, km, rgas, gama, gm2, cp2, kappa, &
     enddo
     do i=is, ie
 #ifdef MOIST_CAPPA
-           p1(i) = t1g*gm2(i,km)/dz2(i,km)*(pem(i,km+1)+pp(i,km+1))
+       p1(i) = t1g*gm2(i,km)/dz2(i,km)*(pem(i,km+1))
 #else
 #ifdef MULTI_GASES
            gamax = 1./(1.-kapad2(i,km))
            t1gx = gamax * 2.*dt*dt
-           p1(i) = t1gx/dz2(i,km)*(pem(i,km+1)+pp(i,km+1))
+           p1(i) = t1gx/dz2(i,km)*(pem(i,km+1))
 #else
-           p1(i) = t1g/dz2(i,km)*(pem(i,km+1)+pp(i,km+1))
+           p1(i) = t1g/dz2(i,km)*(pem(i,km+1))
 #endif
 #endif
        gam(i,km) = aa(i,km) / bet(i)
@@ -1509,6 +1532,16 @@ subroutine SIM1_solver(dt,  is,  ie, km, rgas, gama, gm2, cp2, kappa, &
        enddo
     enddo
 
+!!! Try Rayleigh damping of w
+    if (fast_tau_w_sec > 1.e-5) then
+       !currently not damping to heat
+       do k=1,k_rf
+          do i=is,ie
+             w2(i,k) = w2(i,k)*rff(k)
+          enddo
+       enddo
+    endif
+
     do i=is, ie
        pe(i,1) = 0.
     enddo
@@ -1549,16 +1582,16 @@ subroutine SIM1_solver(dt,  is,  ie, km, rgas, gama, gm2, cp2, kappa, &
        enddo
     enddo
 
- end subroutine SIM1_solver
+  end subroutine SIM1_solver
 
  subroutine SIM_solver(dt,  is,  ie, km, rgas, gama, gm2, cp2, kappa,  &
 #ifdef MULTI_GASES
                        kapad2, &
 #endif
                        pe2, dm2,   &
-                       pm2, pem, w2, dz2, pt2, ws, alpha, p_fac, scale_m)
+                       pm2, pem, w2, dz2, pt2, ws, alpha, p_fac, scale_m, fast_tau_w_sec)
    integer, intent(in):: is, ie, km
-   real, intent(in):: dt, rgas, gama, kappa, p_fac, alpha, scale_m
+   real, intent(in):: dt, rgas, gama, kappa, p_fac, alpha, scale_m, fast_tau_w_sec
    real, intent(in), dimension(is:ie,km):: dm2, pt2, pm2, gm2, cp2
    real, intent(in )::  ws(is:ie)
    real, intent(in ), dimension(is:ie,km+1):: pem
@@ -1637,8 +1670,7 @@ subroutine SIM_solver(dt,  is,  ie, km, rgas, gama, gm2, cp2, kappa,  &
 
     do k=1, km+1
        do i=is, ie
-! pe2 is Full p
-          pe2(i,k) = pem(i,k) + pp(i,k)
+          pe2(i,k) = pem(i,k)
        enddo
     enddo
 
@@ -1697,6 +1729,16 @@ subroutine SIM_solver(dt,  is,  ie, km, rgas, gama, gm2, cp2, kappa,  &
       enddo
     enddo
 
+!!! Try Rayleigh damping of w
+    if (fast_tau_w_sec > 1.e-5) then
+       !currently not damping to heat
+       do k=1,k_rf
+          do i=is,ie
+             w2(i,k) = w2(i,k)*rff(k)
+          enddo
+       enddo
+    endif
+
     do i=is, ie
        pe2(i,1) = 0.
     enddo