cam6_4_091: Implement support for moving mountain gravity wave scheme in MPAS dycore

bld/build-namelist

@@ -3852,10 +3852,10 @@ if (!$simple_phys) {
 
     if ($phys =~ /cam7/) {
 	#
-	# moving mountains only supported by SE dycore
+	# moving mountains only supported by MPAS and SE dycore
 	# (since vorticity needs to be passed to physics in dp_coupling)
 	#
-	if ( $dyn =~ /se/ ) {
+	if ( $dyn =~ /mpas|se/ ) {
 	    add_default($nl, 'use_gw_movmtn_pbl',        'val'=>'.true.');
 	} else {
 	    add_default($nl, 'use_gw_movmtn_pbl',        'val'=>'.false.');
@@ -3864,10 +3864,9 @@ if (!$simple_phys) {
 
     my $use_gw_movmtn_pbl = $nl->get_value('use_gw_movmtn_pbl');
     if ($use_gw_movmtn_pbl =~ /$TRUE/io) {
-         if ( ! ($dyn =~ /se/) ) {
-            die "$ProgName - ERROR: use_gw_movmtn_pbl is only available with the SE dycore \n";
-
-         }
+        if ( ! ($dyn =~ /mpas|se/) ) {
+            die "$ProgName - ERROR: use_gw_movmtn_pbl is only available with MPAS and SE dycore\n";
+        }
     }
 
     add_default($nl, 'use_gw_rdg_gamma' , 'val'=>'.false.');

cime_config/testdefs/testlist_cam.xml

@@ -1677,6 +1677,16 @@
       <option name="comment">CAM7 low top ~40 km with archiving</option>
     </options>
   </test>
+  <test compset="FHISTC_LTso" grid="mpasa480_mpasa480" name="ERS_D_Ln9" testmods="cam/outfrq9s_mpasa480">
+    <machines>
+      <machine name="derecho" compiler="intel" category="aux_cam"/>
+      <machine name="izumi" compiler="gnu" category="aux_cam"/>
+    </machines>
+    <options>
+      <option name="wallclock">00:30:00</option>
+      <option name="comment">CAM7 low top ~40 km with MPAS dynamical core</option>
+    </options>
+  </test>
   <test compset="FHISTC_MTso" grid="ne30pg3_ne30pg3_mt232" name="SMS_D_Ln9" testmods="cam/outfrq9s">
     <machines>
       <machine name="derecho" compiler="intel" category="aux_cam"/>

cime_config/testdefs/testmods_dirs/cam/outfrq9s_mpasa480/user_nl_clm

@@ -1,3 +1,4 @@
+flanduse_timeseries = ''
 hist_nhtfrq = 9
 hist_mfilt  = 1
 hist_ndens  = 1

doc/ChangeLog

@@ -1,5 +1,122 @@
 ===============================================================
 
+Tag name: TBD
+Originator(s): kuanchihwang
+Date: TBD
+One-line Summary: Implement support for moving mountain gravity wave scheme in MPAS dycore
+Github PR URL: https://github.com/ESCOMP/CAM/pull/1297
+
+Purpose of changes (include the issue number and title text for each relevant GitHub issue):
+
+  This PR implements support for moving mountain gravity wave scheme in MPAS dycore.
+
+  The `use_gw_movmtn_pbl` namelist option will now default to `.true.` when MPAS dycore and CAM7
+  physics are both selected.
+
+  The moving mountain gravity wave scheme needs relative vorticities at cell points as input.
+  However, because MPAS uses staggered C-grid for spatial discretization, where wind vectors are
+  located at edge points, it calculates relative vorticities at vertex points instead. As a result,
+  this PR introduces a new functionality in MPAS subdriver to regrid vertex values to cell values.
+  The regridding functionality is also generalized so that it will work with all variables at vertex
+  points.
+
+  Subsequently, relative vorticities are passed to physics buffer during dynamics-physics coupling,
+  after which the moving mountain gravity wave scheme can query and use them as input.
+
+  Closes #1253 (Support for new moving mountains gravity wave trigger with MPAS dycore)
+  Closes #1277 (MPAS dycore support for moving mountains parameterization)
+
+Describe any changes made to build system:
+
+  None
+
+Describe any changes made to the namelist:
+
+  The `use_gw_movmtn_pbl` namelist option will now default to `.true.` when MPAS dycore and CAM7
+  physics are both selected.
+
+List any changes to the defaults for the boundary datasets:
+
+  None
+
+Describe any substantial timing or memory changes:
+
+  None
+
+Code reviewed by:
+
+  PeterHjortLauritzen, mgduda, nusbaume
+
+List all files eliminated:
+
+  None
+
+List all files added and what they do:
+
+  None
+
+List all existing files that have been modified, and describe the changes:
+
+  M       bld/build-namelist
+    * Allow the moving mountain gravity wave scheme to be selected with MPAS dycore
+  M       cime_config/testdefs/testlist_cam.xml
+    * Add testing for CAM7 low top with MPAS dynamical core
+  M       src/dynamics/mpas/dp_coupling.F90
+    * Pass relative vorticities to physics buffer during dynamics-physics coupling
+  M       src/dynamics/mpas/driver/cam_mpas_subdriver.F90
+    * Implement the computation of relative vorticities at cell points
+  M       src/dynamics/mpas/dyn_comp.F90
+    * Pass relative vorticities to physics buffer during dynamics-physics coupling
+
+If there were any failures reported from running test_driver.sh on any test
+platform, and checkin with these failures has been OK'd by the gatekeeper,
+then copy the lines from the td.*.status files for the failed tests to the
+appropriate machine below. All failed tests must be justified.
+
+  NOTE:
+
+  Since cam6_4_089, `model_version`, which is a variable that stores the current model version,
+  has been introduced to `nuopc.runconfig`. However, the testing framework will detect it as a
+  significant difference and fail with "NLCOMP" incorrectly.
+
+  All tests currently exhibit "NLFAIL" in their overall results due to those "NLCOMP" failures.
+
+  They are harmless and can be ignored.
+
+derecho/intel/aux_cam:
+
+  ERS_D_Ln9.mpasa480_mpasa480.FHISTC_LTso.derecho_intel.cam-outfrq9s_mpasa480 (Overall: DIFF) details:
+    FAIL ERS_D_Ln9.mpasa480_mpasa480.FHISTC_LTso.derecho_intel.cam-outfrq9s_mpasa480 BASELINE (Baseline directory does not exist)
+      * New test
+  SMS_D_Ln9_P1280x1.ne0CONUSne30x8_ne0CONUSne30x8_mt12.FCHIST.derecho_intel.cam-outfrq9s (Overall: FAIL) details:
+    FAIL SMS_D_Ln9_P1280x1.ne0CONUSne30x8_ne0CONUSne30x8_mt12.FCHIST.derecho_intel.cam-outfrq9s SETUP
+      * Pre-existing failures due to build-namelist error requiring CLM/CTSM external update
+
+derecho/nvhpc/aux_cam:
+
+  All pass
+
+izumi/nag/aux_cam:
+
+  All pass
+
+izumi/gnu/aux_cam:
+
+  ERS_D_Ln9.mpasa480_mpasa480.FHISTC_LTso.izumi_gnu.cam-outfrq9s_mpasa480 (Overall: DIFF) details:
+    FAIL ERS_D_Ln9.mpasa480_mpasa480.FHISTC_LTso.izumi_gnu.cam-outfrq9s_mpasa480 BASELINE (Baseline directory does not exist)
+      * New test
+
+CAM tag used for the baseline comparison tests if different than previous
+tag:
+
+  cam6_4_090
+
+Summarize any changes to answers:
+
+  None
+
+===============================================================
+
 Tag name: cam6_4_090
 Originator(s): lizziel
 Date: April 30, 2025

src/dynamics/mpas/dp_coupling.F90

@@ -38,15 +38,15 @@ module dp_coupling
 !=========================================================================================
 
 subroutine d_p_coupling(phys_state, phys_tend, pbuf2d, dyn_out)
-   use cam_mpas_subdriver, only: cam_mpas_update_halo
+   use cam_mpas_subdriver, only: cam_mpas_update_halo, cam_mpas_vertex_to_cell_relative_vorticities
 
    ! Convert the dynamics output state into the physics input state.
    ! Note that all pressures and tracer mixing ratios coming from the dycore are based on
    ! dry air mass.
    use cam_history,    only: hist_fld_active
-   use dyn_comp,       only: frontgf_idx, frontga_idx
+   use dyn_comp,       only: frontgf_idx, frontga_idx, vort4gw_idx
    use mpas_constants, only: Rv_over_Rd => rvord
-   use phys_control,   only: use_gw_front, use_gw_front_igw
+   use phys_control,   only: use_gw_front, use_gw_front_igw, use_gw_movmtn_pbl
    use cam_budget,     only : thermo_budget_history
 
    ! arguments
@@ -101,6 +101,12 @@ subroutine d_p_coupling(phys_state, phys_tend, pbuf2d, dyn_out)
    real(r8), allocatable :: frontgf_phys(:,:,:)
    real(r8), allocatable :: frontga_phys(:,:,:)
 
+   ! Temporary arrays to hold vorticity for the "moving mountain" gravity wave scheme.
+   real(r8), allocatable :: vort4gw(:, :)         ! Data are unchunked.
+   real(r8), allocatable :: vort4gw_phys(:, :, :) ! Data are chunked.
+   ! Pointer to vorticity in physics buffer for the "moving mountain" gravity wave scheme.
+   real(r8), pointer :: pbuf_vort4gw(:, :)
+
    type(physics_buffer_desc), pointer :: pbuf_chnk(:)
 
    integer :: lchnk, icol, icol_p, k, kk      ! indices over chunks, columns, physics columns and layers
@@ -116,6 +122,11 @@ subroutine d_p_coupling(phys_state, phys_tend, pbuf2d, dyn_out)
    character(len=*), parameter :: subname = 'd_p_coupling'
    !----------------------------------------------------------------------------
 
+   nullify(pbuf_chnk)
+   nullify(pbuf_frontgf)
+   nullify(pbuf_frontga)
+   nullify(pbuf_vort4gw)
+
    compute_energy_diags=thermo_budget_history
 
    nCellsSolve = dyn_out % nCellsSolve
@@ -155,9 +166,6 @@ subroutine d_p_coupling(phys_state, phys_tend, pbuf2d, dyn_out)
 
    if (use_gw_front .or. use_gw_front_igw) then
       call cam_mpas_update_halo('scalars', endrun)   ! scalars is the name of tracers in the MPAS state pool
-      nullify(pbuf_chnk)
-      nullify(pbuf_frontgf)
-      nullify(pbuf_frontga)
       !
       ! compute frontogenesis function and angle for gravity wave scheme
       !
@@ -195,6 +203,16 @@ subroutine d_p_coupling(phys_state, phys_tend, pbuf2d, dyn_out)
 
    end if
 
+   if (use_gw_movmtn_pbl) then
+      call cam_mpas_vertex_to_cell_relative_vorticities(vort4gw)
+
+      allocate(vort4gw_phys(pcols, pver, begchunk:endchunk), stat=ierr)
+
+      if (ierr /= 0) then
+         call endrun(subname // ': Failed to allocate vort4gw_phys')
+      end if
+   end if
+
    call t_startf('dpcopy')
 
    ncols = columns_on_task
@@ -225,6 +243,10 @@ subroutine d_p_coupling(phys_state, phys_tend, pbuf2d, dyn_out)
             frontgf_phys(icol_p, k, lchnk) = frontogenesisFunction(kk, i)
             frontga_phys(icol_p, k, lchnk) = frontogenesisAngle(kk, i)
          end if
+
+         if (use_gw_movmtn_pbl) then
+            vort4gw_phys(icol_p, k, lchnk) = vort4gw(kk, i)
+         end if
       end do
 
       do k = 1, pverp
@@ -261,6 +283,25 @@ subroutine d_p_coupling(phys_state, phys_tend, pbuf2d, dyn_out)
       deallocate(frontogenesisAngle)
    end if
 
+   if (use_gw_movmtn_pbl) then
+      !$omp parallel do private (lchnk, ncols, icol, k, pbuf_chnk, pbuf_vort4gw)
+      do lchnk = begchunk, endchunk
+         ncols = get_ncols_p(lchnk)
+         pbuf_chnk => pbuf_get_chunk(pbuf2d, lchnk)
+
+         call pbuf_get_field(pbuf_chnk, vort4gw_idx, pbuf_vort4gw)
+
+         do k = 1, pver
+            do icol = 1, ncols
+               pbuf_vort4gw(icol, k) = vort4gw_phys(icol, k, lchnk)
+            end do
+         end do
+      end do
+
+      deallocate(vort4gw)
+      deallocate(vort4gw_phys)
+   end if
+
    call t_stopf('dpcopy')
 
    call t_startf('derived_phys')