From f98c63fe4a5da0ae6ffaee74e7e0dab56263370a Mon Sep 17 00:00:00 2001
From: Haipeng Lin <hplin@ucar.edu>
Date: Thu, 12 Mar 2026 13:15:05 -0400
Subject: [PATCH 1/9] Implement prescribed_volcanic_aerosol (CAM4, CAM5); add
 to tracer_data_test suite

---
 .../chemistry/prescribed_volcanic_aerosol.F90 | 362 ++++++++++++++++++
 .../prescribed_volcanic_aerosol.meta          | 239 ++++++++++++
 .../prescribed_volcanic_aerosol_namelist.xml  | 203 ++++++++++
 test/test_suites/suite_tracer_data_test.xml   |   4 +
 4 files changed, 808 insertions(+)
 create mode 100644 schemes/chemistry/prescribed_volcanic_aerosol.F90
 create mode 100644 schemes/chemistry/prescribed_volcanic_aerosol.meta
 create mode 100644 schemes/chemistry/prescribed_volcanic_aerosol_namelist.xml

diff --git a/schemes/chemistry/prescribed_volcanic_aerosol.F90 b/schemes/chemistry/prescribed_volcanic_aerosol.F90
new file mode 100644
index 00000000..a1a56c9e
--- /dev/null
+++ b/schemes/chemistry/prescribed_volcanic_aerosol.F90
@@ -0,0 +1,362 @@
+! Manages reading and interpolation of prescribed volcanic aerosol concentrations.
+!
+! This module uses CCPP constituents (non-advected) to store prescribed volcanic aero
+! fields:
+! 1) volcanic aerosol mass mixing ratio (from prescribed dataset)
+! 2) geometric-mean wet aerosol radius (derived from mass)
+!
+! Based on original CAM version from: Francis Vitt
+module prescribed_volcanic_aerosol
+  use ccpp_kinds, only: kind_phys
+
+  ! CAM-SIMA host model dependency to read aerosol data
+  use tracer_data, only: trfile     ! data information and file read state
+  use tracer_data, only: trfld      ! tracer data container
+
+  implicit none
+  private
+
+  ! public CCPP-compliant subroutines
+  public :: prescribed_volcanic_aerosol_register
+  public :: prescribed_volcanic_aerosol_init
+  public :: prescribed_volcanic_aerosol_run
+
+  ! fields to store tracer_data state and information
+  type(trfld), pointer :: tracer_data_fields(:)
+  type(trfile)         :: tracer_data_file
+
+  ! module state variables
+  logical :: has_prescribed_volcaero = .false.
+
+  ! Constituent names
+  character(len=*), parameter :: volcaero_const_name = 'VOLC_MMR'
+  character(len=*), parameter :: volcrad_const_name  = 'VOLC_RAD_GEOM'
+
+  ! Molecular weight of volcanic aerosol species (sulfate) [g mol-1]
+  real(kind_phys), parameter :: molmass_volcaero = 47.9981995_kind_phys
+
+  ! WACCM-derived empirical coefficient relating mass concentration
+  ! to wet aerosol geometric-mean radius [m (kg m-3)^(-1/3)]
+  real(kind_phys), parameter :: radius_conversion = 1.9e-4_kind_phys
+
+  ! TODO: infrastructure for writing (and reading) tracer_data restart information.
+  ! see CAM/prescribed_volcrad_aero::{init,read,write}_prescribed_volcaero_restart
+  ! !!! Restarts will not be bit-for-bit without this !!!
+  ! TODO when SIMA implements restarts.
+
+contains
+
+  ! Register prescribed volcanic aerosol constituents.
+!> \section arg_table_prescribed_volcanic_aerosol_register Argument Table
+!! \htmlinclude prescribed_volcanic_aerosol_register.html
+  subroutine prescribed_volcanic_aerosol_register( &
+    amIRoot, iulog, &
+    prescribed_volcaero_file, &
+    volcaero_constituents, &
+    errmsg, errflg)
+
+    use ccpp_constituent_prop_mod, only: ccpp_constituent_properties_t
+
+    ! Input arguments:
+    logical,            intent(in)  :: amIRoot
+    integer,            intent(in)  :: iulog
+    character(len=*),   intent(in)  :: prescribed_volcaero_file          ! input filename from namelist
+
+    ! Output arguments:
+    type(ccpp_constituent_properties_t), allocatable, intent(out) :: volcaero_constituents(:)
+    character(len=*),   intent(out) :: errmsg
+    integer,            intent(out) :: errflg
+
+    character(len=*), parameter :: subname = 'prescribed_volcanic_aerosol_register'
+
+    errmsg = ''
+    errflg = 0
+
+    ! Check if prescribed volcanic aerosols are enabled
+    if (prescribed_volcaero_file == 'NONE' .or. &
+        len_trim(prescribed_volcaero_file) == 0) then
+      has_prescribed_volcaero = .false.
+      if (amIRoot) then
+        write(iulog,*) subname//': No prescribed volcanic aerosols specified'
+      end if
+      return
+    end if
+
+    has_prescribed_volcaero = .true.
+
+    ! Register two constituents: aerosol MMR and geometric-mean radius
+    allocate(volcaero_constituents(2), stat=errflg, errmsg=errmsg)
+    if (errflg /= 0) then
+      errmsg = subname // ": " // trim(errmsg)
+      return
+    end if
+
+    ! (1) Volcanic aerosol dry mass mixing ratio
+    call volcaero_constituents(1)%instantiate( &
+         std_name          = volcaero_const_name, &
+         diag_name         = volcaero_const_name, &
+         long_name         = 'prescribed volcanic aerosol dry mass mixing ratio', &
+         units             = 'kg kg-1', &
+         vertical_dim      = 'vertical_layer_dimension', &
+         min_value         = 0.0_kind_phys, &
+         advected          = .false., &
+         water_species     = .false., &
+         mixing_ratio_type = 'dry', &
+         errcode           = errflg, &
+         errmsg            = errmsg)
+    if (errflg /= 0) return
+
+    ! (2) Volcanic aerosol geometric-mean radius (derived quantity)
+    call volcaero_constituents(2)%instantiate( &
+         std_name          = volcrad_const_name, &
+         diag_name         = volcrad_const_name, &
+         long_name         = 'prescribed volcanic aerosol geometric-mean radius derived from mass', &
+         units             = 'm', &
+         vertical_dim      = 'vertical_layer_dimension', &
+         min_value         = 0.0_kind_phys, &
+         advected          = .false., &
+         water_species     = .false., &
+         mixing_ratio_type = 'dry', &
+         errcode           = errflg, &
+         errmsg            = errmsg)
+    if (errflg /= 0) return
+
+    if (amIRoot) then
+      write(iulog,*) trim(subname)//': Registered 2 prescribed volcanic aerosol constituents'
+    end if
+
+  end subroutine prescribed_volcanic_aerosol_register
+
+  ! Initialize prescribed volcanic aerosol reading via tracer_data.
+!> \section arg_table_prescribed_volcanic_aerosol_init Argument Table
+!! \htmlinclude prescribed_volcanic_aerosol_init.html
+  subroutine prescribed_volcanic_aerosol_init( &
+    amIRoot, iulog, &
+    prescribed_volcaero_name, &
+    prescribed_volcaero_file, &
+    prescribed_volcaero_filelist, &
+    prescribed_volcaero_datapath, &
+    prescribed_volcaero_type, &
+    prescribed_volcaero_cycle_yr, &
+    prescribed_volcaero_fixed_ymd, &
+    prescribed_volcaero_fixed_tod, &
+    errmsg, errflg)
+
+    ! host model dependency for tracer_data read utility
+    use tracer_data, only: trcdata_init
+
+    ! host model dependency for history output
+    use cam_history,         only: history_add_field
+    use cam_history_support, only: horiz_only
+
+    ! Input arguments:
+    logical,            intent(in)  :: amIRoot
+    integer,            intent(in)  :: iulog
+    character(len=*),   intent(in)  :: prescribed_volcaero_name          ! netCDF field name for volcanic aerosol
+    character(len=*),   intent(in)  :: prescribed_volcaero_file          ! input filename from namelist
+    character(len=*),   intent(in)  :: prescribed_volcaero_filelist      ! input filelist from namelist
+    character(len=*),   intent(in)  :: prescribed_volcaero_datapath      ! input datapath from namelist
+    character(len=*),   intent(in)  :: prescribed_volcaero_type          ! data type from namelist
+    integer,            intent(in)  :: prescribed_volcaero_cycle_yr      ! cycle year from namelist [1]
+    integer,            intent(in)  :: prescribed_volcaero_fixed_ymd     ! fixed year-month-day from namelist (YYYYMMDD) [1]
+    integer,            intent(in)  :: prescribed_volcaero_fixed_tod     ! fixed time of day from namelist [s]
+
+    ! Output arguments:
+    character(len=*),   intent(out) :: errmsg
+    integer,            intent(out) :: errflg
+
+    ! Local variables:
+    character(len=64) :: specifier(1)
+
+    character(len=*), parameter :: subname = 'prescribed_volcanic_aerosol_init'
+
+    errmsg = ''
+    errflg = 0
+
+    if (.not. has_prescribed_volcaero) return
+
+    if (amIRoot) then
+      write(iulog,*) trim(subname)//': volcanic aerosol is prescribed in: '// &
+           trim(prescribed_volcaero_file)
+    end if
+
+    ! Build specifier: constituent_name:ncdf_field_name
+    specifier(1) = trim(volcaero_const_name) // ':' // trim(prescribed_volcaero_name)
+
+    ! Initialize tracer_data module with file and field information
+    call trcdata_init( &
+      specifier      = specifier, &
+      filename       = prescribed_volcaero_file, &
+      filelist       = prescribed_volcaero_filelist, &
+      datapath       = prescribed_volcaero_datapath, &
+      flds           = tracer_data_fields, &
+      file           = tracer_data_file, &
+      data_cycle_yr  = prescribed_volcaero_cycle_yr, &
+      data_fixed_ymd = prescribed_volcaero_fixed_ymd, &
+      data_fixed_tod = prescribed_volcaero_fixed_tod, &
+      data_type      = prescribed_volcaero_type)
+
+    ! Verify tracer_data is correctly initialized
+    if (.not. associated(tracer_data_fields)) then
+      errflg = 1
+      errmsg = subname//': tracer_data_fields not associated after trcdata_init'
+      return
+    end if
+
+    ! Register history fields
+    call history_add_field(volcaero_const_name, &
+         'prescribed volcanic aerosol dry mass mixing ratio', &
+         'lev', 'inst', 'kg kg-1')
+    call history_add_field(volcrad_const_name, &
+         'volcanic aerosol geometric-mean radius', &
+         'lev', 'inst', 'm')
+    call history_add_field('VOLC_MASS', &
+         'volcanic aerosol vertical mass path in layer', &
+         'lev', 'inst', 'kg m-2')
+    call history_add_field('VOLC_MASS_C', &
+         'volcanic aerosol column mass', &
+         horiz_only, 'inst', 'kg m-2')
+
+    if (amIRoot) then
+      write(iulog,*) trim(subname)//': Initialized volcanic aerosol field from tracer_data'
+    end if
+
+  end subroutine prescribed_volcanic_aerosol_init
+
+  ! Advance prescribed volcanic aerosol data, convert units, apply tropopause
+  ! masking, and compute geometric-mean radius.
+!> \section arg_table_prescribed_volcanic_aerosol_run Argument Table
+!! \htmlinclude prescribed_volcanic_aerosol_run.html
+  subroutine prescribed_volcanic_aerosol_run( &
+    ncol, pver, pcnst, &
+    const_props, &
+    mwdry, boltz, gravit, &
+    T, pmiddry, pdel, zm, &
+    pmid, pint, phis, zi, &
+    tropLev, &
+    constituents, &
+    errmsg, errflg)
+
+    ! host model dependency for tracer_data
+    use tracer_data,               only: advance_trcdata
+
+    ! host model dependency for history output
+    use cam_history,               only: history_out_field
+
+    ! framework dependency for const_props
+    use ccpp_constituent_prop_mod, only: ccpp_constituent_prop_ptr_t
+
+    ! dependency to get constituent index
+    use ccpp_const_utils,          only: ccpp_const_get_idx
+
+    ! dependency for unit string handling
+    use string_utils,              only: to_lower, GLC
+
+    integer,            intent(in)    :: ncol
+    integer,            intent(in)    :: pver
+    integer,            intent(in)    :: pcnst
+    type(ccpp_constituent_prop_ptr_t), &
+                        intent(in)    :: const_props(:)
+    real(kind_phys),    intent(in)    :: mwdry             ! molecular weight of dry air [g mol-1]
+    real(kind_phys),    intent(in)    :: boltz             ! Boltzmann constant [J K-1 molecule-1]
+    real(kind_phys),    intent(in)    :: gravit            ! gravitational acceleration [m s-2]
+    real(kind_phys),    intent(in)    :: T(:,:)            ! air temperature [K] (layer centers)
+    real(kind_phys),    intent(in)    :: pmiddry(:,:)      ! dry air pressure [Pa] (layer centers)
+    real(kind_phys),    intent(in)    :: pdel(:,:)         ! air pressure thickness [Pa] (layer centers)
+    real(kind_phys),    intent(in)    :: zm(:,:)           ! geopotential height wrt surface [m] (layer centers)
+    real(kind_phys),    intent(in)    :: pmid(:,:)         ! air pressure [Pa] (layer centers)
+    real(kind_phys),    intent(in)    :: pint(:,:)         ! air pressure at interfaces [Pa]
+    real(kind_phys),    intent(in)    :: phis(:)           ! surface geopotential [m2 s-2]
+    real(kind_phys),    intent(in)    :: zi(:,:)           ! geopotential height wrt surface at interfaces [m]
+    integer,            intent(in)    :: tropLev(:)        ! tropopause vertical layer index [index]
+
+    real(kind_phys),    intent(inout) :: constituents(:,:,:)
+
+    character(len=*),   intent(out)   :: errmsg
+    integer,            intent(out)   :: errflg
+
+    ! Local variables
+    integer         :: i, k
+    integer         :: mmr_idx, rad_idx
+    real(kind_phys) :: to_mmr(ncol, pver)    ! unit conversion factor to MMR [1]
+    real(kind_phys) :: mmrvolc               ! volcanic aerosol MMR [kg kg-1]
+    real(kind_phys) :: concvolc              ! mass concentration of volcanic aerosol [kg m-3]
+    real(kind_phys) :: volcmass(ncol, pver)  ! volcanic aerosol mass path in layer [kg m-2]
+    real(kind_phys) :: columnmass(ncol)      ! volcanic aerosol column mass [kg m-2]
+
+    character(len=*), parameter :: subname = 'prescribed_volcanic_aerosol_run'
+
+    errmsg = ''
+    errflg = 0
+
+    if (.not. has_prescribed_volcaero) return
+
+    ! Advance tracer_data to current time
+    call advance_trcdata(tracer_data_fields, tracer_data_file, &
+                         pmid, pint, phis, zi)
+
+    ! Get constituent indices for MMR and radius
+    call ccpp_const_get_idx(const_props, volcaero_const_name, &
+         mmr_idx, errmsg, errflg)
+    if (errflg /= 0) return
+
+    call ccpp_const_get_idx(const_props, volcrad_const_name, &
+         rad_idx, errmsg, errflg)
+    if (errflg /= 0) return
+
+    ! Determine unit conversion factor based on units in the input file
+    select case ( to_lower(trim(tracer_data_fields(1)%units(:GLC(tracer_data_fields(1)%units)))) )
+    case ("molec/cm3", "/cm3", "molecules/cm3", "cm^-3", "cm**-3")
+      ! Number density [molecules cm-3] -> MMR [kg kg-1]
+      ! mmr = (M * 1e6 * k_B * T) / (M_air * p_dry)
+      to_mmr(:ncol,:) = (molmass_volcaero * 1.0e6_kind_phys * boltz * T(:ncol,:)) &
+                       / (mwdry * pmiddry(:ncol,:))
+    case ('kg/kg', 'mmr', 'kg kg-1')
+      to_mmr(:ncol,:) = 1.0_kind_phys
+    case ('mol/mol', 'mole/mole', 'vmr', 'fraction')
+      to_mmr(:ncol,:) = molmass_volcaero / mwdry
+    case default
+      errflg = 1
+      errmsg = subname//': unrecognized units: '//trim(tracer_data_fields(1)%units)
+      return
+    end select
+
+    ! Convert tracer_data field to MMR and store in constituent array.
+    ! Apply tropopause masking: zero below tropopause.
+    ! Compute geometric-mean radius where MMR > 0 above tropopause.
+    constituents(:ncol, :pver, rad_idx) = 0.0_kind_phys
+
+    do k = 1, pver
+      do i = 1, ncol
+        ! Apply unit conversion
+        mmrvolc = to_mmr(i, k) * tracer_data_fields(1)%data(i, k)
+
+        ! Zero below tropopause
+        if (k >= tropLev(i)) then
+          mmrvolc = 0.0_kind_phys
+        end if
+
+        constituents(i, k, mmr_idx) = mmrvolc
+
+        ! Compute geometric-mean wet aerosol radius from mass concentration
+        if (mmrvolc > 0.0_kind_phys) then
+          ! concvolc [kg m-3] = mmr [kg kg-1] * pdel [Pa] / (g [m s-2] * zm [m])
+          concvolc = (mmrvolc * pdel(i, k)) / (gravit * zm(i, k))
+          constituents(i, k, rad_idx) = radius_conversion * (concvolc ** (1.0_kind_phys / 3.0_kind_phys))
+        end if
+      end do
+    end do
+
+    ! Compute volcanic aerosol mass path in each layer [kg m-2]
+    volcmass(:ncol, :pver)  = constituents(:ncol, :pver, mmr_idx) * pdel(:ncol, :pver) / gravit
+    columnmass(:ncol) = sum(volcmass(:ncol, :pver), 2)
+
+    ! History output
+    call history_out_field(volcaero_const_name, constituents(:, :, mmr_idx))
+    call history_out_field(volcrad_const_name,  constituents(:, :, rad_idx))
+    call history_out_field('VOLC_MASS',   volcmass(:, :))
+    call history_out_field('VOLC_MASS_C', columnmass(:))
+
+  end subroutine prescribed_volcanic_aerosol_run
+
+end module prescribed_volcanic_aerosol
diff --git a/schemes/chemistry/prescribed_volcanic_aerosol.meta b/schemes/chemistry/prescribed_volcanic_aerosol.meta
new file mode 100644
index 00000000..d56f7c49
--- /dev/null
+++ b/schemes/chemistry/prescribed_volcanic_aerosol.meta
@@ -0,0 +1,239 @@
+[ccpp-table-properties]
+  name = prescribed_volcanic_aerosol
+  type = scheme
+
+[ccpp-arg-table]
+  name  = prescribed_volcanic_aerosol_register
+  type  = scheme
+[ amIRoot ]
+  standard_name = flag_for_mpi_root
+  units = flag
+  type = logical
+  dimensions = ()
+  intent = in
+[ iulog ]
+  standard_name = log_output_unit
+  units = 1
+  type = integer
+  dimensions = ()
+  intent = in
+[ prescribed_volcaero_file ]
+  standard_name = filename_for_prescribed_volcanic_aerosol
+  units = none
+  type = character | kind = len=*
+  dimensions = ()
+  intent = in
+[ volcaero_constituents ]
+  # or can this just be the ccpp_constituent_properties?
+  standard_name = prescribed_volcanic_aerosol_constituents
+  units = none
+  type = ccpp_constituent_properties_t
+  allocatable = True
+  dimensions = (:)
+  intent = out
+[ errmsg ]
+  standard_name = ccpp_error_message
+  units = none
+  type = character | kind = len=*
+  dimensions = ()
+  intent = out
+[ errflg ]
+  standard_name = ccpp_error_code
+  units = 1
+  type = integer
+  dimensions = ()
+  intent = out
+
+[ccpp-arg-table]
+  name  = prescribed_volcanic_aerosol_init
+  type  = scheme
+[ amIRoot ]
+  standard_name = flag_for_mpi_root
+  units = flag
+  type = logical
+  dimensions = ()
+  intent = in
+[ iulog ]
+  standard_name = log_output_unit
+  units = 1
+  type = integer
+  dimensions = ()
+  intent = in
+[ prescribed_volcaero_name ]
+  standard_name = variable_name_of_volcanic_aerosol_in_file_for_prescribed_volcanic_aerosol
+  units = none
+  type = character | kind = len=*
+  dimensions = ()
+  intent = in
+[ prescribed_volcaero_file ]
+  standard_name = filename_for_prescribed_volcanic_aerosol
+  units = none
+  type = character | kind = len=*
+  dimensions = ()
+  intent = in
+[ prescribed_volcaero_filelist ]
+  standard_name = filename_of_file_list_for_prescribed_volcanic_aerosol
+  units = none
+  type = character | kind = len=*
+  dimensions = ()
+  intent = in
+[ prescribed_volcaero_datapath ]
+  standard_name = datapath_for_prescribed_volcanic_aerosol
+  units = none
+  type = character | kind = len=*
+  dimensions = ()
+  intent = in
+[ prescribed_volcaero_type ]
+  standard_name = time_interpolation_method_for_prescribed_volcanic_aerosol
+  units = none
+  type = character | kind = len=*
+  dimensions = ()
+  intent = in
+[ prescribed_volcaero_cycle_yr ]
+  standard_name = cycle_year_for_prescribed_volcanic_aerosol
+  units = 1
+  type = integer
+  dimensions = ()
+  intent = in
+[ prescribed_volcaero_fixed_ymd ]
+  standard_name = fixed_date_for_prescribed_volcanic_aerosol
+  units = 1
+  type = integer
+  dimensions = ()
+  intent = in
+[ prescribed_volcaero_fixed_tod ]
+  standard_name = fixed_time_of_day_for_prescribed_volcanic_aerosol
+  units = s
+  type = integer
+  dimensions = ()
+  intent = in
+[ errmsg ]
+  standard_name = ccpp_error_message
+  units = none
+  type = character | kind = len=*
+  dimensions = ()
+  intent = out
+[ errflg ]
+  standard_name = ccpp_error_code
+  units = 1
+  type = integer
+  dimensions = ()
+  intent = out
+
+[ccpp-arg-table]
+  name  = prescribed_volcanic_aerosol_run
+  type  = scheme
+[ ncol ]
+  standard_name = horizontal_loop_extent
+  units = count
+  type = integer
+  dimensions = ()
+  intent = in
+[ pver ]
+  standard_name = vertical_layer_dimension
+  units = count
+  type = integer
+  dimensions = ()
+  intent = in
+[ pcnst ]
+  standard_name = number_of_ccpp_constituents
+  units = count
+  type = integer
+  dimensions = ()
+  intent = in
+[ const_props ]
+  standard_name = ccpp_constituent_properties
+  units = none
+  type = ccpp_constituent_prop_ptr_t
+  dimensions = (number_of_ccpp_constituents)
+  intent = in
+[ mwdry ]
+  standard_name = molecular_weight_of_dry_air
+  units = g mol-1
+  type = real | kind = kind_phys
+  dimensions = ()
+  intent = in
+[ boltz ]
+  standard_name = boltzmann_constant
+  units = J K-1
+  type = real | kind = kind_phys
+  dimensions = ()
+  intent = in
+[ gravit ]
+  standard_name = standard_gravitational_acceleration
+  units = m s-2
+  type = real | kind = kind_phys
+  dimensions = ()
+  intent = in
+[ T ]
+  standard_name = air_temperature
+  units = K
+  type = real | kind = kind_phys
+  dimensions = (horizontal_loop_extent, vertical_layer_dimension)
+  intent = in
+[ pmiddry ]
+  standard_name = air_pressure_of_dry_air
+  units = Pa
+  type = real | kind = kind_phys
+  dimensions = (horizontal_loop_extent, vertical_layer_dimension)
+  intent = in
+[ pdel ]
+  standard_name = air_pressure_thickness
+  units = Pa
+  type = real | kind = kind_phys
+  dimensions = (horizontal_dimension, vertical_layer_dimension)
+  intent = in
+[ zm ]
+  standard_name = geopotential_height_wrt_surface
+  units = m
+  type = real | kind = kind_phys
+  dimensions = (horizontal_dimension, vertical_layer_dimension)
+  intent = in
+[ pmid ]
+  standard_name = air_pressure
+  units = Pa
+  type = real | kind = kind_phys
+  dimensions = (horizontal_loop_extent, vertical_layer_dimension)
+  intent = in
+[ pint ]
+  standard_name = air_pressure_at_interface
+  units = Pa
+  type = real | kind = kind_phys
+  dimensions = (horizontal_loop_extent, vertical_interface_dimension)
+  intent = in
+[ phis ]
+  standard_name = surface_geopotential
+  units = m2 s-2
+  type = real | kind = kind_phys
+  dimensions = (horizontal_loop_extent)
+  intent = in
+[ zi ]
+  standard_name = geopotential_height_wrt_surface_at_interface
+  units = m
+  type = real | kind = kind_phys
+  dimensions = (horizontal_loop_extent, vertical_interface_dimension)
+  intent = in
+[ tropLev ]
+  standard_name = tropopause_vertical_layer_index
+  units = index
+  type = integer
+  dimensions = (horizontal_loop_extent)
+  intent = in
+[ constituents ]
+  standard_name = ccpp_constituents
+  units = none
+  type = real | kind = kind_phys
+  dimensions = (horizontal_loop_extent, vertical_layer_dimension, number_of_ccpp_constituents)
+  intent = inout
+[ errmsg ]
+  standard_name = ccpp_error_message
+  units = none
+  type = character | kind = len=*
+  dimensions = ()
+  intent = out
+[ errflg ]
+  standard_name = ccpp_error_code
+  units = 1
+  type = integer
+  dimensions = ()
+  intent = out
diff --git a/schemes/chemistry/prescribed_volcanic_aerosol_namelist.xml b/schemes/chemistry/prescribed_volcanic_aerosol_namelist.xml
new file mode 100644
index 00000000..cc2a8e25
--- /dev/null
+++ b/schemes/chemistry/prescribed_volcanic_aerosol_namelist.xml
@@ -0,0 +1,203 @@
+<?xml version="1.0"?>
+
+<?xml-stylesheet type="text/xsl"?>
+
+<entry_id_pg version="2.0">
+
+<!-- Each namelist variable is defined in an <entry> element.  The
+     content of the element is the documentation of how the variable is
+     used.  Other aspects of the variable's definition are expressed as
+     attributes of the <entry> element.  Note that it is an XML requirement
+     that the attribute values are enclosed in quotes.  The attributes are:
+
+     id
+          The variable's name.  *** N.B. *** The name must be lower case.
+          The module convert all namelist variable names to lower case
+          since Fortran is case insensitive.
+
+     type
+          An abbreviation of the fortran declaration for the variable.
+    Valid declarations are:
+
+          char*n
+    integer
+    logical
+    real
+
+    Any of these types may be followed by a comma separated list of
+    integers enclosed in parenthesis to indicate an array.
+
+    The current namelist validation code only distinquishes between
+    string and non-string types.
+
+     input_pathname
+          Only include this attribute to indicate that the variable
+          contains the pathname of an input dataset that resides in the
+          CESM inputdata directory tree.  Note that the variables
+          containing the names of restart files that are used in branch
+          runs don't reside in the inputdata tree and should not be given
+          this attribute.
+
+    The recognized values are "abs" to indicate that an absolute
+          pathname is required, or "rel:var_name" to indicate that the
+          pathname is relative and that the namelist variable "var_name"
+          contains the absolute root directory.
+
+     category
+          A category assigned for organizing the documentation.
+
+     group
+          The namelist group that the variable is declared in.
+
+     valid_values
+          This is an optional attribute that is mainly useful for variables
+          that have only a small number of allowed values. It is a
+          comma-separated list of valid values for the variable.
+
+     desc
+          This is a text description of the variable including its
+          purpose and use.
+
+     values
+          This is a grouping of all the cases where a value can be
+          assigned with the namelist generator has been run.
+
+     value
+          Each <value> tag specifies a case where a value is assigned
+          to this variable when the namelist generator is run. If the
+          tag has no attributes, it is a default value. In general,
+          the namelist generator attempts to find a value with the
+          maximium number of attribute matches (and no non-matches).
+
+     standard_name
+          This is the CCPP Standard Name of the variable
+
+     units
+          This is the CCPP unit specification of the variable (e.g., m s-1).
+                                                                        -->
+  <entry id="prescribed_volcaero_datapath">
+    <type>char*256</type>
+    <category>chemistry</category>
+    <group>prescribed_volcaero_nl</group>
+    <standard_name>datapath_for_prescribed_volcanic_aerosol</standard_name>
+    <units>none</units>
+    <desc>
+      Full pathname of the directory that contains the files specified in prescribed_volcaero_filelist.
+    </desc>
+    <values>
+      <value></value>
+      <value phys_suite="cam4">${DIN_LOC_ROOT}/atm/cam/volc</value>
+      <value phys_suite="cam5">${DIN_LOC_ROOT}/atm/cam/volc</value>
+    </values>
+  </entry>
+
+  <entry id="prescribed_volcaero_file">
+    <type>char*256</type>
+    <category>chemistry</category>
+    <group>prescribed_volcaero_nl</group>
+    <standard_name>filename_for_prescribed_volcanic_aerosol</standard_name>
+    <units>none</units>
+    <desc>
+      Filename of dataset for prescribed volcanic aerosols.
+    </desc>
+    <values>
+      <value></value>
+      <value phys_suite="cam4">CCSM4_volcanic_1850-2008_prototype1.nc</value>
+      <value phys_suite="cam5">CCSM4_volcanic_1850-2008_prototype1.nc</value>
+    </values>
+  </entry>
+
+  <entry id="prescribed_volcaero_filelist">
+    <type>char*256</type>
+    <category>chemistry</category>
+    <group>prescribed_volcaero_nl</group>
+    <standard_name>filename_of_file_list_for_prescribed_volcanic_aerosol</standard_name>
+    <units>none</units>
+    <desc>
+      Filename of file that contains a sequence of filenames for prescribed volcanic aerosols.
+      The filenames in this file are relative to the directory specified by prescribed_volcaero_datapath.
+    </desc>
+    <values>
+      <value></value>
+    </values>
+  </entry>
+
+  <entry id="prescribed_volcaero_name">
+    <type>char*16</type>
+    <category>chemistry</category>
+    <group>prescribed_volcaero_nl</group>
+    <standard_name>variable_name_of_volcanic_aerosol_in_file_for_prescribed_volcanic_aerosol</standard_name>
+    <units>none</units>
+    <desc>
+      Name of variable containing volcanic aerosol data in the prescribed volcanic aerosol datasets.
+      Default: 'MMRVOLC'
+    </desc>
+    <values>
+      <value>MMRVOLC</value>
+    </values>
+  </entry>
+
+  <entry id="prescribed_volcaero_type">
+    <type>char*32</type>
+    <category>chemistry</category>
+    <group>prescribed_volcaero_nl</group>
+    <standard_name>time_interpolation_method_for_prescribed_volcanic_aerosol</standard_name>
+    <units>none</units>
+    <valid_values>CYCLICAL,SERIAL,INTERP_MISSING_MONTHS,FIXED</valid_values>
+    <desc>
+      Type of time interpolation for data in prescribed_aero files.
+      Can be set to 'CYCLICAL', 'SERIAL', 'INTERP_MISSING_MONTHS', or 'FIXED'.
+      Default: 'SERIAL'
+    </desc>
+    <values>
+      <value>SERIAL</value>
+    </values>
+  </entry>
+
+  <entry id="prescribed_volcaero_cycle_yr">
+    <type>integer</type>
+    <category>chemistry</category>
+    <group>prescribed_volcaero_nl</group>
+    <standard_name>cycle_year_for_prescribed_volcanic_aerosol</standard_name>
+    <units>1</units>
+    <desc>
+      The cycle year of the prescribed volcanic aerosol data if prescribed_volcaero_type is 'CYCLICAL'.
+      Format: YYYY
+      Default: 0
+    </desc>
+    <values>
+      <value>0</value>
+    </values>
+  </entry>
+
+  <entry id="prescribed_volcaero_fixed_ymd">
+    <type>integer</type>
+    <category>chemistry</category>
+    <group>prescribed_volcaero_nl</group>
+    <standard_name>fixed_date_for_prescribed_volcanic_aerosol</standard_name>
+    <units>1</units>
+    <desc>
+      The date at which the prescribed volcanic aerosol data is fixed if prescribed_volcaero_type is 'FIXED'.
+      Format: YYYYMMDD
+      Default: 0
+    </desc>
+    <values>
+      <value>0</value>
+    </values>
+  </entry>
+
+  <entry id="prescribed_volcaero_fixed_tod">
+    <type>integer</type>
+    <category>chemistry</category>
+    <group>prescribed_volcaero_nl</group>
+    <standard_name>fixed_time_of_day_for_prescribed_volcanic_aerosol</standard_name>
+    <units>s</units>
+    <desc>
+      The time of day (seconds) corresponding to prescribed_volcaero_fixed_ymd at which the prescribed volcanic aerosol data is fixed if prescribed_aero_type is 'FIXED'.
+      Default: 0 seconds
+    </desc>
+    <values>
+      <value>0</value>
+    </values>
+  </entry>
+</entry_id_pg>
diff --git a/test/test_suites/suite_tracer_data_test.xml b/test/test_suites/suite_tracer_data_test.xml
index c7f7319d..ca4df619 100644
--- a/test/test_suites/suite_tracer_data_test.xml
+++ b/test/test_suites/suite_tracer_data_test.xml
@@ -10,5 +10,9 @@
 
     <!-- prescribed aerosol deposition flux (requires prescribed_aerosols) -->
     <scheme>prescribed_aerosol_deposition_flux</scheme>
+
+    <!-- prescribed volcanic aerosol (simpler, like prescribed_ozone) (CAM4, CAM5) -->
+    <scheme>tropopause_find</scheme>
+    <scheme>prescribed_volcanic_aerosol</scheme>
   </group>
 </suite>

From 37afbefa1354c77cebc464ae84e4c65f74650f4d Mon Sep 17 00:00:00 2001
From: Haipeng Lin <hplin@ucar.edu>
Date: Thu, 12 Mar 2026 13:39:41 -0400
Subject: [PATCH 2/9] Update UNSET (since paramgen does not like empty values);
 GLC

---
 schemes/chemistry/prescribed_volcanic_aerosol.F90          | 6 +++---
 schemes/chemistry/prescribed_volcanic_aerosol.meta         | 4 ++--
 schemes/chemistry/prescribed_volcanic_aerosol_namelist.xml | 6 +++---
 3 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/schemes/chemistry/prescribed_volcanic_aerosol.F90 b/schemes/chemistry/prescribed_volcanic_aerosol.F90
index a1a56c9e..0c14cc2b 100644
--- a/schemes/chemistry/prescribed_volcanic_aerosol.F90
+++ b/schemes/chemistry/prescribed_volcanic_aerosol.F90
@@ -73,7 +73,7 @@ subroutine prescribed_volcanic_aerosol_register( &
     errflg = 0
 
     ! Check if prescribed volcanic aerosols are enabled
-    if (prescribed_volcaero_file == 'NONE' .or. &
+    if (prescribed_volcaero_file == 'UNSET' .or. &
         len_trim(prescribed_volcaero_file) == 0) then
       has_prescribed_volcaero = .false.
       if (amIRoot) then
@@ -250,7 +250,7 @@ subroutine prescribed_volcanic_aerosol_run( &
     use ccpp_const_utils,          only: ccpp_const_get_idx
 
     ! dependency for unit string handling
-    use string_utils,              only: to_lower, GLC
+    use string_utils,              only: to_lower, get_last_significant_char
 
     integer,            intent(in)    :: ncol
     integer,            intent(in)    :: pver
@@ -305,7 +305,7 @@ subroutine prescribed_volcanic_aerosol_run( &
     if (errflg /= 0) return
 
     ! Determine unit conversion factor based on units in the input file
-    select case ( to_lower(trim(tracer_data_fields(1)%units(:GLC(tracer_data_fields(1)%units)))) )
+    select case ( to_lower(trim(tracer_data_fields(1)%units(:get_last_significant_char(tracer_data_fields(1)%units)))) )
     case ("molec/cm3", "/cm3", "molecules/cm3", "cm^-3", "cm**-3")
       ! Number density [molecules cm-3] -> MMR [kg kg-1]
       ! mmr = (M * 1e6 * k_B * T) / (M_air * p_dry)
diff --git a/schemes/chemistry/prescribed_volcanic_aerosol.meta b/schemes/chemistry/prescribed_volcanic_aerosol.meta
index d56f7c49..5545b159 100644
--- a/schemes/chemistry/prescribed_volcanic_aerosol.meta
+++ b/schemes/chemistry/prescribed_volcanic_aerosol.meta
@@ -181,13 +181,13 @@
   standard_name = air_pressure_thickness
   units = Pa
   type = real | kind = kind_phys
-  dimensions = (horizontal_dimension, vertical_layer_dimension)
+  dimensions = (horizontal_loop_extent, vertical_layer_dimension)
   intent = in
 [ zm ]
   standard_name = geopotential_height_wrt_surface
   units = m
   type = real | kind = kind_phys
-  dimensions = (horizontal_dimension, vertical_layer_dimension)
+  dimensions = (horizontal_loop_extent, vertical_layer_dimension)
   intent = in
 [ pmid ]
   standard_name = air_pressure
diff --git a/schemes/chemistry/prescribed_volcanic_aerosol_namelist.xml b/schemes/chemistry/prescribed_volcanic_aerosol_namelist.xml
index cc2a8e25..ad6c343d 100644
--- a/schemes/chemistry/prescribed_volcanic_aerosol_namelist.xml
+++ b/schemes/chemistry/prescribed_volcanic_aerosol_namelist.xml
@@ -85,7 +85,7 @@
       Full pathname of the directory that contains the files specified in prescribed_volcaero_filelist.
     </desc>
     <values>
-      <value></value>
+      <value>UNSET</value>
       <value phys_suite="cam4">${DIN_LOC_ROOT}/atm/cam/volc</value>
       <value phys_suite="cam5">${DIN_LOC_ROOT}/atm/cam/volc</value>
     </values>
@@ -101,7 +101,7 @@
       Filename of dataset for prescribed volcanic aerosols.
     </desc>
     <values>
-      <value></value>
+      <value>UNSET</value>
       <value phys_suite="cam4">CCSM4_volcanic_1850-2008_prototype1.nc</value>
       <value phys_suite="cam5">CCSM4_volcanic_1850-2008_prototype1.nc</value>
     </values>
@@ -118,7 +118,7 @@
       The filenames in this file are relative to the directory specified by prescribed_volcaero_datapath.
     </desc>
     <values>
-      <value></value>
+      <value>UNSET</value>
     </values>
   </entry>
 

From 7c4a0c798ce96c5cab16c6d3a5dac6914035e625 Mon Sep 17 00:00:00 2001
From: Haipeng Lin <hplin@ucar.edu>
Date: Fri, 13 Mar 2026 14:30:28 -0400
Subject: [PATCH 3/9] Fix boltz physconst units.

---
 schemes/chemistry/prescribed_ozone.meta            | 2 +-
 schemes/chemistry/prescribed_volcanic_aerosol.meta | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/schemes/chemistry/prescribed_ozone.meta b/schemes/chemistry/prescribed_ozone.meta
index 3e0b9d84..6db778a7 100644
--- a/schemes/chemistry/prescribed_ozone.meta
+++ b/schemes/chemistry/prescribed_ozone.meta
@@ -150,7 +150,7 @@
   intent = in
 [ boltz ]
   standard_name = boltzmann_constant
-  units = J K-1
+  units = J K-1 molecule-1
   type = real | kind = kind_phys
   dimensions = ()
   intent = in
diff --git a/schemes/chemistry/prescribed_volcanic_aerosol.meta b/schemes/chemistry/prescribed_volcanic_aerosol.meta
index 5545b159..3123859c 100644
--- a/schemes/chemistry/prescribed_volcanic_aerosol.meta
+++ b/schemes/chemistry/prescribed_volcanic_aerosol.meta
@@ -155,7 +155,7 @@
   intent = in
 [ boltz ]
   standard_name = boltzmann_constant
-  units = J K-1
+  units = J K-1 molecule-1
   type = real | kind = kind_phys
   dimensions = ()
   intent = in

From df29ac0d9a07c7b0a6635e6ef15ace3cbe992da5 Mon Sep 17 00:00:00 2001
From: Haipeng Lin <hplin@ucar.edu>
Date: Sat, 14 Mar 2026 11:54:27 -0400
Subject: [PATCH 4/9] cherry-picked from trunk
 175ea9ebb6e40f5a17f082f1df47b71597121791

to cherry-pick: remove constituent diag in prescribe_volcanic_aerosol
---
 schemes/chemistry/prescribed_volcanic_aerosol.F90 | 12 +++---------
 1 file changed, 3 insertions(+), 9 deletions(-)

diff --git a/schemes/chemistry/prescribed_volcanic_aerosol.F90 b/schemes/chemistry/prescribed_volcanic_aerosol.F90
index 0c14cc2b..afabe639 100644
--- a/schemes/chemistry/prescribed_volcanic_aerosol.F90
+++ b/schemes/chemistry/prescribed_volcanic_aerosol.F90
@@ -203,13 +203,9 @@ subroutine prescribed_volcanic_aerosol_init( &
       return
     end if
 
-    ! Register history fields
-    call history_add_field(volcaero_const_name, &
-         'prescribed volcanic aerosol dry mass mixing ratio', &
-         'lev', 'inst', 'kg kg-1')
-    call history_add_field(volcrad_const_name, &
-         'volcanic aerosol geometric-mean radius', &
-         'lev', 'inst', 'm')
+    ! Register history fields.
+    ! No longer need history output for the constituents because, well,
+    ! they are constituents.
     call history_add_field('VOLC_MASS', &
          'volcanic aerosol vertical mass path in layer', &
          'lev', 'inst', 'kg m-2')
@@ -352,8 +348,6 @@ subroutine prescribed_volcanic_aerosol_run( &
     columnmass(:ncol) = sum(volcmass(:ncol, :pver), 2)
 
     ! History output
-    call history_out_field(volcaero_const_name, constituents(:, :, mmr_idx))
-    call history_out_field(volcrad_const_name,  constituents(:, :, rad_idx))
     call history_out_field('VOLC_MASS',   volcmass(:, :))
     call history_out_field('VOLC_MASS_C', columnmass(:))
 

From 9b8852de84a090a7f9b36924740c7c9c40851f68 Mon Sep 17 00:00:00 2001
From: Haipeng Lin <hplin@ucar.edu>
Date: Mon, 6 Apr 2026 15:20:01 -0400
Subject: [PATCH 5/9] Add sima_state_diagnostics to test SDF to get volc_mmr
 constituent diag

---
 test/test_suites/suite_tracer_data_test.xml | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/test/test_suites/suite_tracer_data_test.xml b/test/test_suites/suite_tracer_data_test.xml
index ca4df619..39f1ec65 100644
--- a/test/test_suites/suite_tracer_data_test.xml
+++ b/test/test_suites/suite_tracer_data_test.xml
@@ -14,5 +14,8 @@
     <!-- prescribed volcanic aerosol (simpler, like prescribed_ozone) (CAM4, CAM5) -->
     <scheme>tropopause_find</scheme>
     <scheme>prescribed_volcanic_aerosol</scheme>
+
+    <!-- constituent diagnostics (VOLC_MMR) -->
+    <scheme>sima_state_diagnostics</scheme>
   </group>
 </suite>

From e812a6bf6d55502b0fa339f5311c947d1dab13d1 Mon Sep 17 00:00:00 2001
From: Haipeng Lin <hplin@ucar.edu>
Date: Mon, 11 May 2026 06:32:31 -0400
Subject: [PATCH 6/9] Address review comments

---
 schemes/chemistry/prescribed_ozone.meta       |  2 +-
 .../chemistry/prescribed_volcanic_aerosol.F90 | 23 ++++++-------------
 .../prescribed_volcanic_aerosol.meta          |  3 +--
 3 files changed, 9 insertions(+), 19 deletions(-)

diff --git a/schemes/chemistry/prescribed_ozone.meta b/schemes/chemistry/prescribed_ozone.meta
index 6db778a7..3e0b9d84 100644
--- a/schemes/chemistry/prescribed_ozone.meta
+++ b/schemes/chemistry/prescribed_ozone.meta
@@ -150,7 +150,7 @@
   intent = in
 [ boltz ]
   standard_name = boltzmann_constant
-  units = J K-1 molecule-1
+  units = J K-1
   type = real | kind = kind_phys
   dimensions = ()
   intent = in
diff --git a/schemes/chemistry/prescribed_volcanic_aerosol.F90 b/schemes/chemistry/prescribed_volcanic_aerosol.F90
index afabe639..a7145267 100644
--- a/schemes/chemistry/prescribed_volcanic_aerosol.F90
+++ b/schemes/chemistry/prescribed_volcanic_aerosol.F90
@@ -75,7 +75,6 @@ subroutine prescribed_volcanic_aerosol_register( &
     ! Check if prescribed volcanic aerosols are enabled
     if (prescribed_volcaero_file == 'UNSET' .or. &
         len_trim(prescribed_volcaero_file) == 0) then
-      has_prescribed_volcaero = .false.
       if (amIRoot) then
         write(iulog,*) subname//': No prescribed volcanic aerosols specified'
       end if
@@ -204,8 +203,6 @@ subroutine prescribed_volcanic_aerosol_init( &
     end if
 
     ! Register history fields.
-    ! No longer need history output for the constituents because, well,
-    ! they are constituents.
     call history_add_field('VOLC_MASS', &
          'volcanic aerosol vertical mass path in layer', &
          'lev', 'inst', 'kg m-2')
@@ -225,7 +222,6 @@ end subroutine prescribed_volcanic_aerosol_init
 !! \htmlinclude prescribed_volcanic_aerosol_run.html
   subroutine prescribed_volcanic_aerosol_run( &
     ncol, pver, pcnst, &
-    const_props, &
     mwdry, boltz, gravit, &
     T, pmiddry, pdel, zm, &
     pmid, pint, phis, zi, &
@@ -239,11 +235,8 @@ subroutine prescribed_volcanic_aerosol_run( &
     ! host model dependency for history output
     use cam_history,               only: history_out_field
 
-    ! framework dependency for const_props
-    use ccpp_constituent_prop_mod, only: ccpp_constituent_prop_ptr_t
-
-    ! dependency to get constituent index
-    use ccpp_const_utils,          only: ccpp_const_get_idx
+    ! framework dependency to get constituent index
+    use ccpp_scheme_utils,         only: ccpp_constituent_index
 
     ! dependency for unit string handling
     use string_utils,              only: to_lower, get_last_significant_char
@@ -251,10 +244,8 @@ subroutine prescribed_volcanic_aerosol_run( &
     integer,            intent(in)    :: ncol
     integer,            intent(in)    :: pver
     integer,            intent(in)    :: pcnst
-    type(ccpp_constituent_prop_ptr_t), &
-                        intent(in)    :: const_props(:)
     real(kind_phys),    intent(in)    :: mwdry             ! molecular weight of dry air [g mol-1]
-    real(kind_phys),    intent(in)    :: boltz             ! Boltzmann constant [J K-1 molecule-1]
+    real(kind_phys),    intent(in)    :: boltz             ! Boltzmann constant [J K-1]
     real(kind_phys),    intent(in)    :: gravit            ! gravitational acceleration [m s-2]
     real(kind_phys),    intent(in)    :: T(:,:)            ! air temperature [K] (layer centers)
     real(kind_phys),    intent(in)    :: pmiddry(:,:)      ! dry air pressure [Pa] (layer centers)
@@ -292,12 +283,12 @@ subroutine prescribed_volcanic_aerosol_run( &
                          pmid, pint, phis, zi)
 
     ! Get constituent indices for MMR and radius
-    call ccpp_const_get_idx(const_props, volcaero_const_name, &
-         mmr_idx, errmsg, errflg)
+    call ccpp_constituent_index(volcaero_const_name, &
+         mmr_idx, errmsg=errmsg, errcode=errflg)
     if (errflg /= 0) return
 
-    call ccpp_const_get_idx(const_props, volcrad_const_name, &
-         rad_idx, errmsg, errflg)
+    call ccpp_constituent_index(volcrad_const_name, &
+         rad_idx, errmsg=errmsg, errcode=errflg)
     if (errflg /= 0) return
 
     ! Determine unit conversion factor based on units in the input file
diff --git a/schemes/chemistry/prescribed_volcanic_aerosol.meta b/schemes/chemistry/prescribed_volcanic_aerosol.meta
index 3123859c..290e76ad 100644
--- a/schemes/chemistry/prescribed_volcanic_aerosol.meta
+++ b/schemes/chemistry/prescribed_volcanic_aerosol.meta
@@ -24,7 +24,6 @@
   dimensions = ()
   intent = in
 [ volcaero_constituents ]
-  # or can this just be the ccpp_constituent_properties?
   standard_name = prescribed_volcanic_aerosol_constituents
   units = none
   type = ccpp_constituent_properties_t
@@ -155,7 +154,7 @@
   intent = in
 [ boltz ]
   standard_name = boltzmann_constant
-  units = J K-1 molecule-1
+  units = J K-1
   type = real | kind = kind_phys
   dimensions = ()
   intent = in

From 1649409b0927d7effd901ed56cc3b31b11835841 Mon Sep 17 00:00:00 2001
From: Haipeng Lin <hplin@ucar.edu>
Date: Mon, 11 May 2026 23:11:50 -0400
Subject: [PATCH 7/9] Remove extraneous const_props

---
 schemes/chemistry/prescribed_volcanic_aerosol.meta | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/schemes/chemistry/prescribed_volcanic_aerosol.meta b/schemes/chemistry/prescribed_volcanic_aerosol.meta
index 290e76ad..a37655b7 100644
--- a/schemes/chemistry/prescribed_volcanic_aerosol.meta
+++ b/schemes/chemistry/prescribed_volcanic_aerosol.meta
@@ -140,12 +140,6 @@
   type = integer
   dimensions = ()
   intent = in
-[ const_props ]
-  standard_name = ccpp_constituent_properties
-  units = none
-  type = ccpp_constituent_prop_ptr_t
-  dimensions = (number_of_ccpp_constituents)
-  intent = in
 [ mwdry ]
   standard_name = molecular_weight_of_dry_air
   units = g mol-1

From 68a09edd99336f2ed17832059879c6308bf5e74b Mon Sep 17 00:00:00 2001
From: Haipeng Lin <hplin@ucar.edu>
Date: Wed, 13 May 2026 14:18:03 -0400
Subject: [PATCH 8/9] Address review comments

---
 schemes/chemistry/prescribed_volcanic_aerosol.F90          | 4 +++-
 schemes/chemistry/prescribed_volcanic_aerosol.meta         | 4 ++--
 schemes/chemistry/prescribed_volcanic_aerosol_namelist.xml | 2 +-
 3 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/schemes/chemistry/prescribed_volcanic_aerosol.F90 b/schemes/chemistry/prescribed_volcanic_aerosol.F90
index a7145267..20e0a7e3 100644
--- a/schemes/chemistry/prescribed_volcanic_aerosol.F90
+++ b/schemes/chemistry/prescribed_volcanic_aerosol.F90
@@ -121,7 +121,9 @@ subroutine prescribed_volcanic_aerosol_register( &
     if (errflg /= 0) return
 
     if (amIRoot) then
-      write(iulog,*) trim(subname)//': Registered 2 prescribed volcanic aerosol constituents'
+      write(iulog,*) trim(subname)//&
+        ': Registered 2 prescribed volcanic aerosol constituents: '//&
+        volcaero_const_name//', '//volcrad_const_name
     end if
 
   end subroutine prescribed_volcanic_aerosol_register
diff --git a/schemes/chemistry/prescribed_volcanic_aerosol.meta b/schemes/chemistry/prescribed_volcanic_aerosol.meta
index a37655b7..8d2f67a0 100644
--- a/schemes/chemistry/prescribed_volcanic_aerosol.meta
+++ b/schemes/chemistry/prescribed_volcanic_aerosol.meta
@@ -18,7 +18,7 @@
   dimensions = ()
   intent = in
 [ prescribed_volcaero_file ]
-  standard_name = filename_for_prescribed_volcanic_aerosol
+  standard_name = filename_of_prescribed_volcanic_aerosol
   units = none
   type = character | kind = len=*
   dimensions = ()
@@ -65,7 +65,7 @@
   dimensions = ()
   intent = in
 [ prescribed_volcaero_file ]
-  standard_name = filename_for_prescribed_volcanic_aerosol
+  standard_name = filename_of_prescribed_volcanic_aerosol
   units = none
   type = character | kind = len=*
   dimensions = ()
diff --git a/schemes/chemistry/prescribed_volcanic_aerosol_namelist.xml b/schemes/chemistry/prescribed_volcanic_aerosol_namelist.xml
index ad6c343d..506733d1 100644
--- a/schemes/chemistry/prescribed_volcanic_aerosol_namelist.xml
+++ b/schemes/chemistry/prescribed_volcanic_aerosol_namelist.xml
@@ -95,7 +95,7 @@
     <type>char*256</type>
     <category>chemistry</category>
     <group>prescribed_volcaero_nl</group>
-    <standard_name>filename_for_prescribed_volcanic_aerosol</standard_name>
+    <standard_name>filename_of_prescribed_volcanic_aerosol</standard_name>
     <units>none</units>
     <desc>
       Filename of dataset for prescribed volcanic aerosols.

From 962296b72c986ddfceba07cc23b53b8ad1e675ca Mon Sep 17 00:00:00 2001
From: Haipeng Lin <hplin@ucar.edu>
Date: Wed, 13 May 2026 14:20:29 -0400
Subject: [PATCH 9/9] Update remaining filename_for_ to filename_of_ to match
 ESMStandardNames rules

---
 schemes/chemistry/prescribed_aerosol_deposition_flux.meta     | 2 +-
 .../chemistry/prescribed_aerosol_deposition_flux_namelist.xml | 2 +-
 schemes/chemistry/prescribed_aerosols.meta                    | 4 ++--
 schemes/chemistry/prescribed_aerosols_namelist.xml            | 2 +-
 4 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/schemes/chemistry/prescribed_aerosol_deposition_flux.meta b/schemes/chemistry/prescribed_aerosol_deposition_flux.meta
index 7f932c58..18bc6d01 100644
--- a/schemes/chemistry/prescribed_aerosol_deposition_flux.meta
+++ b/schemes/chemistry/prescribed_aerosol_deposition_flux.meta
@@ -24,7 +24,7 @@
   dimensions = (aerodep_flx_specifier_dimension)
   intent = in
 [ filename ]
-  standard_name = filename_for_prescribed_aerosol_deposition_fluxes
+  standard_name = filename_of_prescribed_aerosol_deposition_fluxes
   units = none
   type = character | kind = len=*
   dimensions = ()
diff --git a/schemes/chemistry/prescribed_aerosol_deposition_flux_namelist.xml b/schemes/chemistry/prescribed_aerosol_deposition_flux_namelist.xml
index 3e421355..03de316b 100644
--- a/schemes/chemistry/prescribed_aerosol_deposition_flux_namelist.xml
+++ b/schemes/chemistry/prescribed_aerosol_deposition_flux_namelist.xml
@@ -93,7 +93,7 @@
     <type>char*256</type>
     <category>chemistry</category>
     <group>aerodep_flx_nl</group>
-    <standard_name>filename_for_prescribed_aerosol_deposition_fluxes</standard_name>
+    <standard_name>filename_of_prescribed_aerosol_deposition_fluxes</standard_name>
     <units>none</units>
     <desc>
       Filename of dataset for prescribed aerosol deposition fluxes.
diff --git a/schemes/chemistry/prescribed_aerosols.meta b/schemes/chemistry/prescribed_aerosols.meta
index eec2debe..6e4ba68d 100644
--- a/schemes/chemistry/prescribed_aerosols.meta
+++ b/schemes/chemistry/prescribed_aerosols.meta
@@ -25,7 +25,7 @@
   dimensions = (prescribed_aero_specifier_dimension)
   intent = in
 [ prescribed_aero_file ]
-  standard_name = filename_for_prescribed_aerosols
+  standard_name = filename_of_prescribed_aerosols
   units = none
   type = character | kind = len=*
   dimensions = ()
@@ -115,7 +115,7 @@
   dimensions = (prescribed_aero_specifier_dimension)
   intent = in
 [ prescribed_aero_file ]
-  standard_name = filename_for_prescribed_aerosols
+  standard_name = filename_of_prescribed_aerosols
   units = none
   type = character | kind = len=*
   dimensions = ()
diff --git a/schemes/chemistry/prescribed_aerosols_namelist.xml b/schemes/chemistry/prescribed_aerosols_namelist.xml
index 878043b6..c248eda1 100644
--- a/schemes/chemistry/prescribed_aerosols_namelist.xml
+++ b/schemes/chemistry/prescribed_aerosols_namelist.xml
@@ -117,7 +117,7 @@
     <type>char*256</type>
     <category>chemistry</category>
     <group>prescribed_aero_nl</group>
-    <standard_name>filename_for_prescribed_aerosols</standard_name>
+    <standard_name>filename_of_prescribed_aerosols</standard_name>
     <units>none</units>
     <desc>
       Filename of dataset for prescribed aerosols.