diff --git a/scripts/ccpp_datafile.py b/scripts/ccpp_datafile.py
index e02061fc..9ceee5b8 100755
--- a/scripts/ccpp_datafile.py
+++ b/scripts/ccpp_datafile.py
@@ -890,7 +890,7 @@ def _new_var_entry(parent, var, full_entry=True):
     >>> var = Var({'local_name' : 'foo', 'standard_name' : 'hi_mom', 'units' : 'm s-1', 'dimensions' : '(horizontal_loop_extent)', 'type' : 'real', 'intent' : 'in'}, ParseSource('vname', 'DDT', ParseContext()), _MVAR_DUMMY_RUN_ENV)
     >>> _new_var_entry(parent, var)
     >>> table_entry_pretty_print(parent, 0)
-    '<variables>\\n  <var name=hi_mom intent=in local_name=foo active=.true. kind=kind_phys persistence=timestep type=real units=m s-1>\\n    <dimensions>\\n      horizontal_loop_extent\\n    </dimensions>\\n    <source_type>\\n      ddt\\n    </source_type>\\n    <source_name>\\n      vname\\n    </source_name>\\n  </var>\\n</variables>\\n'
+    '<variables>\\n  <var name=hi_mom intent=in local_name=foo active=.true. diagnostic_name=foo kind=kind_phys persistence=timestep type=real units=m s-1>\\n    <dimensions>\\n      horizontal_loop_extent\\n    </dimensions>\\n    <source_type>\\n      ddt\\n    </source_type>\\n    <source_name>\\n      vname\\n    </source_name>\\n  </var>\\n</variables>\\n'
 
     >>> parent = ET.fromstring('<variables></variables>')
     >>> _new_var_entry(parent, var, full_entry=False)
diff --git a/scripts/constituents.py b/scripts/constituents.py
index bb83c3c7..e7e182c0 100644
--- a/scripts/constituents.py
+++ b/scripts/constituents.py
@@ -300,6 +300,7 @@ def write_constituent_routines(self, outfile, indent, suite_name, err_vars):
             # end if
             outfile.write("index = index + 1", indent+1)
             long_name = var.get_prop_value('long_name')
+            diag_name = var.get_prop_value('diagnostic_name')
             units = var.get_prop_value('units')
             dims = var.get_dim_stdnames()
             default_value = var.get_prop_value('default_value')
@@ -311,7 +312,7 @@ def write_constituent_routines(self, outfile, indent, suite_name, err_vars):
                 vertical_dim = ''
             # end if
             advect_str = self.TF_string(var.get_prop_value('advected'))
-            init_args = [f'{std_name=}', f'{long_name=}',
+            init_args = [f'{std_name=}', f'{long_name=}', f'{diag_name=}',
                          f'{units=}', f'{vertical_dim=}',
                          f'advected={advect_str}',
                          f'errcode={errvar_names["ccpp_error_code"]}',
diff --git a/scripts/metavar.py b/scripts/metavar.py
index 62badfd7..cafdbf9f 100755
--- a/scripts/metavar.py
+++ b/scripts/metavar.py
@@ -26,7 +26,7 @@
 from parse_tools import FORTRAN_CONDITIONAL_REGEX_WORDS, FORTRAN_CONDITIONAL_REGEX
 from var_props import CCPP_LOOP_DIM_SUBSTS, VariableProperty, VarCompatObj
 from var_props import find_horizontal_dimension, find_vertical_dimension
-from var_props import standard_name_to_long_name, default_kind_val
+from var_props import standard_name_to_long_name, local_name_to_diag_name, default_kind_val
 
 ##############################################################################
 
@@ -174,6 +174,9 @@ class Var:
                                      check_fn_in=check_cf_standard_name),
                     VariableProperty('long_name', str, optional_in=True,
                                      default_fn_in=standard_name_to_long_name),
+                    VariableProperty('diagnostic_name', str, optional_in=True,
+                                     default_fn_in=local_name_to_diag_name,
+                                     check_fn_in=check_diagnostic_id),
                     VariableProperty('units', str,
                                      check_fn_in=check_units),
                     VariableProperty('dimensions', list,
@@ -189,9 +192,6 @@ class Var:
                                      optional_in=True, default_in=False),
                     VariableProperty('allocatable', bool,
                                      optional_in=True, default_in=False),
-                    VariableProperty('diagnostic_name', str,
-                                     optional_in=True, default_in='',
-                                     check_fn_in=check_diagnostic_id),
                     VariableProperty('diagnostic_name_fixed', str,
                                      optional_in=True, default_in='',
                                      check_fn_in=check_diagnostic_fixed),
diff --git a/scripts/var_props.py b/scripts/var_props.py
index a53e8b68..fc217548 100755
--- a/scripts/var_props.py
+++ b/scripts/var_props.py
@@ -128,6 +128,44 @@ def find_vertical_dimension(dims):
     # end for
     return (var_vdim, vindex)
 
+########################################################################
+def local_name_to_diag_name(prop_dict, context=None):
+########################################################################
+    """
+    Translate a local_name to its default diagnostic name.
+    Currently, this is just equal to the local name. If no local name
+    exists in the property dictionary, a truncation of the standard
+    name is used. (256 characters = max length of NetCDF variable name)
+    >>> local_name_to_diag_name({'local_name':'foo', 'standard_nam':'cloud_optical_depth'})
+    'foo'
+    >>> local_name_to_diag_name({'standard_name':'cloud_optical_depth_layers_from_0p55mu_to_0p99mu'})
+    'cloud_optical_depth_layers_from_0p55mu_to_0p99mu'
+    >>> local_name_to_diag_name({'units':'km'}) #doctest: +ELLIPSIS
+    Traceback (most recent call last):
+    ...
+    parse_source.CCPPError: No standard name or local name to convert to diagnostic name
+    """
+    diag_name = None
+    if 'local_name' in prop_dict:
+        locname = prop_dict['local_name']
+        if locname:
+            diag_name = prop_dict['local_name']
+        # end if
+    elif 'standard_name' in prop_dict:
+        stdname = prop_dict['standard_name']
+        if stdname:
+            maxlen = 256
+            diag_name = stdname[:maxlen]
+        # end if
+    # end if
+
+    if not diag_name:
+        emsg = 'No standard name or local name to convert to diagnostic name'
+        raise CCPPError(emsg)
+    # end if
+
+    return diag_name
+
 ########################################################################
 def standard_name_to_long_name(prop_dict, context=None):
 ########################################################################
diff --git a/src/ccpp_constituent_prop_mod.F90 b/src/ccpp_constituent_prop_mod.F90
index a08291b6..29e8a365 100644
--- a/src/ccpp_constituent_prop_mod.F90
+++ b/src/ccpp_constituent_prop_mod.F90
@@ -34,6 +34,7 @@ module ccpp_constituent_prop_mod
       !   for a constituent species and provides interfaces to access that data.
       character(len=:), private, allocatable :: var_std_name
       character(len=:), private, allocatable :: var_long_name
+      character(len=:), private, allocatable :: var_diag_name
       character(len=:), private, allocatable :: var_units
       character(len=:), private, allocatable :: vert_dim
       integer,          private              :: const_ind = int_unassigned
@@ -60,6 +61,7 @@ module ccpp_constituent_prop_mod
       procedure :: is_instantiated           => ccp_is_instantiated
       procedure :: standard_name             => ccp_get_standard_name
       procedure :: long_name                 => ccp_get_long_name
+      procedure :: diagnostic_name           => ccp_get_diagnostic_name
       procedure :: units                     => ccp_get_units
       procedure :: is_layer_var              => ccp_is_layer_var
       procedure :: is_interface_var          => ccp_is_interface_var
@@ -103,6 +105,7 @@ module ccpp_constituent_prop_mod
       ! Informational methods
       procedure :: standard_name             => ccpt_get_standard_name
       procedure :: long_name                 => ccpt_get_long_name
+      procedure :: diagnostic_name           => ccpt_get_diagnostic_name
       procedure :: units                     => ccpt_get_units
       procedure :: is_layer_var              => ccpt_is_layer_var
       procedure :: is_interface_var          => ccpt_is_interface_var
@@ -219,6 +222,7 @@ subroutine copyConstituent(outConst, inConst)
 
       outConst%var_std_name        = inConst%var_std_name
       outConst%var_long_name       = inConst%var_long_name
+      outConst%var_diag_name       = inConst%var_diag_name
       outConst%vert_dim            = inConst%vert_dim
       outConst%const_ind           = inConst%const_ind
       outConst%advected            = inConst%advected
@@ -373,8 +377,8 @@ end function ccp_is_instantiated
 
    !#######################################################################
 
-   subroutine ccp_instantiate(this, std_name, long_name, units, vertical_dim,  &
-        advected, default_value, min_value, molar_mass, water_species,         &
+   subroutine ccp_instantiate(this, std_name, long_name, diag_name, units,            &
+        vertical_dim, advected, default_value, min_value, molar_mass, water_species,  &
         mixing_ratio_type, errcode, errmsg)
       ! Initialize all fields in <this>
 
@@ -382,6 +386,7 @@ subroutine ccp_instantiate(this, std_name, long_name, units, vertical_dim,  &
       class(ccpp_constituent_properties_t), intent(inout) :: this
       character(len=*),                     intent(in)    :: std_name
       character(len=*),                     intent(in)    :: long_name
+      character(len=*),                     intent(in)    :: diag_name
       character(len=*),                     intent(in)    :: units
       character(len=*),                     intent(in)    :: vertical_dim
       logical, optional,                    intent(in)    :: advected
@@ -404,6 +409,7 @@ subroutine ccp_instantiate(this, std_name, long_name, units, vertical_dim,  &
       end if
       if (errcode == 0) then
          this%var_long_name = trim(long_name)
+         this%var_diag_name = trim(diag_name)
          this%var_units = trim(units)
          this%vert_dim = trim(vertical_dim)
          if (present(advected)) then
@@ -479,6 +485,9 @@ subroutine ccp_deallocate(this)
       if (allocated(this%var_long_name)) then
          deallocate(this%var_long_name)
       end if
+      if (allocated(this%var_diag_name)) then
+         deallocate(this%var_diag_name)
+      end if
       if (allocated(this%vert_dim)) then
          deallocate(this%vert_dim)
       end if
@@ -530,6 +539,25 @@ end subroutine ccp_get_long_name
 
    !#######################################################################
 
+   subroutine ccp_get_diagnostic_name(this, diag_name, errcode, errmsg)
+      ! Return this constituent's diagnostic name
+
+      ! Dummy arguments
+      class(ccpp_constituent_properties_t), intent(in)  :: this
+      character(len=*),                     intent(out) :: diag_name
+      integer,          optional,           intent(out) :: errcode
+      character(len=*), optional,           intent(out) :: errmsg
+
+      if (this%is_instantiated(errcode, errmsg)) then
+         diag_name = this%var_diag_name
+      else
+         diag_name = ''
+      end if
+
+   end subroutine ccp_get_diagnostic_name
+
+   !#######################################################################
+
    subroutine ccp_get_units(this, units, errcode, errmsg)
       ! Return this constituent's units
 
@@ -763,6 +791,7 @@ subroutine ccp_is_equivalent(this, oconst, equiv, errcode, errmsg)
            oconst%is_instantiated(errcode, errmsg)) then
          equiv = (trim(this%var_std_name) == trim(oconst%var_std_name)) .and. &
               (trim(this%var_long_name) == trim(oconst%var_long_name))  .and. &
+              (trim(this%var_diag_name) == trim(oconst%var_diag_name))  .and. &
               (trim(this%vert_dim) == trim(oconst%vert_dim))            .and. &
               (trim(this%var_units) == trim(oconst%var_units))          .and. &
               (this%advected .eqv. oconst%advected)                     .and. &
@@ -1007,7 +1036,6 @@ logical function ccp_is_match(this, comp_props) result(is_match)
       ! Local variable
       logical :: val, comp_val
       character(len=stdname_len) :: char_val, char_comp_val
-      logical :: check
 
       ! By default, every constituent is a match
       is_match = .true.
@@ -1989,6 +2017,29 @@ end subroutine ccpt_get_long_name
 
    !#######################################################################
 
+   subroutine ccpt_get_diagnostic_name(this, diag_name, errcode, errmsg)
+      ! Return this constituent's diagnostic name
+
+      ! Dummy arguments
+      class(ccpp_constituent_prop_ptr_t), intent(in)  :: this
+      character(len=*),                   intent(out) :: diag_name
+      integer,          optional,         intent(out) :: errcode
+      character(len=*), optional,         intent(out) :: errmsg
+      ! Local variable
+      character(len=*), parameter :: subname = 'ccpt_get_diagnostic_name'
+
+      if (associated(this%prop)) then
+         call this%prop%diagnostic_name(diag_name, errcode, errmsg)
+      else
+         diag_name = ''
+         call append_errvars(1, ": invalid constituent pointer",        &
+              subname, errcode=errcode, errmsg=errmsg)
+      end if
+
+   end subroutine ccpt_get_diagnostic_name
+
+   !#######################################################################
+
    subroutine ccpt_get_units(this, units, errcode, errmsg)
       ! Return this constituent's units
 
diff --git a/test/advection_test/cld_ice.F90 b/test/advection_test/cld_ice.F90
index 759bcab1..15f5b502 100644
--- a/test/advection_test/cld_ice.F90
+++ b/test/advection_test/cld_ice.F90
@@ -34,13 +34,13 @@ subroutine cld_ice_register(dyn_const_ice, errmsg, errcode)
          return
       end if
       call dyn_const_ice(1)%instantiate(std_name='dyn_const1', long_name='dyn const1', &
-           units='kg kg-1', default_value=0._kind_phys,                            &
-           vertical_dim='vertical_layer_dimension', advected=.true.,               &
-           min_value=1000._kind_phys, water_species=.true., mixing_ratio_type='wet', &
+           diag_name='DYNCONST1', units='kg kg-1', default_value=0._kind_phys,         &
+           vertical_dim='vertical_layer_dimension', advected=.true.,                   &
+           min_value=1000._kind_phys, water_species=.true., mixing_ratio_type='wet',   &
            errcode=errcode, errmsg=errmsg)
       call dyn_const_ice(2)%instantiate(std_name='dyn_const2_wrt_moist_air', long_name='dyn const2', &
-           units='kg kg-1', default_value=0._kind_phys,                            &
-           vertical_dim='vertical_layer_dimension', advected=.true.,               &
+           diag_name='DYNCONST2', units='kg kg-1', default_value=0._kind_phys,                       &
+           vertical_dim='vertical_layer_dimension', advected=.true.,                                 &
            water_species=.false., errcode=errcode, errmsg=errmsg)
 
    end subroutine cld_ice_register
diff --git a/test/advection_test/cld_liq.F90 b/test/advection_test/cld_liq.F90
index 023a608c..83a6f961 100644
--- a/test/advection_test/cld_liq.F90
+++ b/test/advection_test/cld_liq.F90
@@ -31,7 +31,7 @@ subroutine cld_liq_register(dyn_const, errmsg, errflg)
          return
       end if
       call dyn_const(1)%instantiate(std_name="dyn_const3_wrt_moist_air_and_condensed_water", long_name='dyn const3', &
-           units='kg kg-1', default_value=1._kind_phys,                            &
+           diag_name='DYNCONST3', units='kg kg-1', default_value=1._kind_phys,     &
            vertical_dim='vertical_layer_dimension', advected=.true.,               &
            water_species=.true., mixing_ratio_type='dry',                          &
            errcode=errflg, errmsg=errmsg)
diff --git a/test/advection_test/cld_liq.meta b/test/advection_test/cld_liq.meta
index e55dcfe7..b3ef3a0d 100644
--- a/test/advection_test/cld_liq.meta
+++ b/test/advection_test/cld_liq.meta
@@ -105,6 +105,7 @@
   intent = in
 [ cld_liq_array ]
   standard_name = cloud_liquid_dry_mixing_ratio
+  diagnostic_name = CLDLIQ
   advected = .true.
   units = kg kg-1
   dimensions = (horizontal_dimension, vertical_layer_dimension)
diff --git a/test/advection_test/dlc_liq.F90 b/test/advection_test/dlc_liq.F90
index 93230f81..db456073 100644
--- a/test/advection_test/dlc_liq.F90
+++ b/test/advection_test/dlc_liq.F90
@@ -31,7 +31,7 @@ subroutine dlc_liq_init(dyn_const, errmsg, errflg)
          return
       end if
       call dyn_const(1)%instantiate(std_name="dyn_const3", long_name='dyn const3', &
-           units='kg kg-1', default_value=1._kind_phys,                            &
+           diag_name='DYNCONST3', units='kg kg-1', default_value=1._kind_phys,     &
            vertical_dim='vertical_layer_dimension', advected=.true.,               &
            errcode=errflg, errmsg=errmsg)
       call dyn_const(1)%standard_name(stdname, errcode=errflg, errmsg=errmsg)
diff --git a/test/advection_test/test_host.F90 b/test/advection_test/test_host.F90
index c1482a93..30a618e8 100644
--- a/test/advection_test/test_host.F90
+++ b/test/advection_test/test_host.F90
@@ -266,12 +266,12 @@ subroutine test_host(retval, test_suites)
               'constituent with this name already exists'
       allocate(host_constituents(2))
       call host_constituents(1)%instantiate(std_name="specific_humidity",     &
-           long_name="Specific humidity", units="kg kg-1",                    &
+           long_name="Specific humidity", diag_name='H2O', units="kg kg-1",   &
            vertical_dim="vertical_layer_dimension", advected=.true.,          &
            min_value=1000._kind_phys, molar_mass=2000._kind_phys,             &
            errcode=errflg, errmsg=errmsg)
       call host_constituents(2)%instantiate(std_name="specific_humidity",     &
-           long_name="Specific humidity", units="kg kg",                      &
+           long_name="Specific humidity", diag_name='H2O', units="kg kg",     &
            vertical_dim="vertical_layer_dimension", advected=.true.,          &
            min_value=1000._kind_phys, molar_mass=2000._kind_phys,             &
            errcode=errflg, errmsg=errmsg)
@@ -309,12 +309,12 @@ subroutine test_host(retval, test_suites)
       end do
       allocate(host_constituents(2))
       call host_constituents(1)%instantiate(std_name="specific_humidity",     &
-           long_name="Specific humidity", units="kg kg-1",                    &
+           long_name="Specific humidity", diag_name='H2O', units="kg kg-1",   &
            vertical_dim="vertical_layer_dimension", advected=.true.,          &
-           min_value=1000._kind_phys, molar_mass=2000._kind_phys,           &
+           min_value=1000._kind_phys, molar_mass=2000._kind_phys,             &
            errcode=errflg, errmsg=errmsg)
       call host_constituents(2)%instantiate(std_name="specific_humidity",     &
-           long_name="Specific humidity", units="kg kg-1",                    &
+           long_name="Specific humidity", diag_name='H2O', units="kg kg-1",   &
            vertical_dim="vertical_layer_dimension", advected=.true.,          &
            min_value=1000._kind_phys, molar_mass=2000._kind_phys,           &
            errcode=errflg, errmsg=errmsg)
@@ -480,6 +480,63 @@ subroutine test_host(retval, test_suites)
          ! Reset error flag to continue testing other properties:
          errflg = 0
       end if
+
+      ! Diagnostic name:
+      call const_props(index_liq)%diagnostic_name(const_str, errflg, errmsg)
+      if (errflg /= 0) then
+         write(6, '(a,i0,a,i0,/,a)') "ERROR: Error, ", errflg, " trying ",    &
+               "to get diagnostic name for cld_liq index = ",                       &
+               index_liq, trim(errmsg)
+         errflg_final = -1 ! Notify test script that a failure occured
+      end if
+      if (errflg == 0) then
+         if (trim(const_str) /= 'CLDLIQ') then
+            write(6, *) "ERROR: diagnostic name, '", trim(const_str),               &
+                 "' should be 'CLDLIQ'"
+            errflg_final = -1 ! Notify test script that a failure occured
+         end if
+      else
+         ! Reset error flag to continue testing other properties:
+         errflg = 0
+      end if
+      ! Check default diagnostic name is set correctly
+      call const_props(index_ice)%diagnostic_name(const_str, errflg, errmsg)
+      if (errflg /= 0) then
+         write(6, '(a,i0,a,i0,/,a)') "ERROR: Error, ", errflg, " trying ",    &
+               "to get diagnostic name for cld_ice index = ",                       &
+               index_ice, trim(errmsg)
+         errflg_final = -1 ! Notify test script that a failure occured
+      end if
+      if (errflg == 0) then
+         if (trim(const_str) /= 'cld_ice_array') then
+            write(6, *) "ERROR: diagnostic name, '", trim(const_str),               &
+                 "' should be 'cld_ice_array'"
+            errflg_final = -1 ! Notify test script that a failure occured
+         end if
+      else
+         ! Reset error flag to continue testing other properties:
+         errflg = 0
+      end if
+      ! Check diagnostic name of a dynamic constituent
+      call const_props(index_dyn2)%diagnostic_name(const_str, errflg,     &
+           errmsg)
+      if (errflg /= 0) then
+         write(6, '(a,i0,a,a,i0,/,a)') "ERROR: Error, ", errflg, " trying ",  &
+              "to get diagnostic name for dyn_const2 index = ",           &
+              index_dyn2, trim(errmsg)
+         errflg_final = -1 ! Notify test script that a failure occured
+      end if
+      if (errflg == 0) then
+         if (trim(const_str) /= 'DYNCONST2') then
+            write(6, *) "ERROR: diagnostic name, '", trim(const_str),               &
+                 "' should be 'DYNCONST2'"
+            errflg_final = -1 ! Notify test script that a failure occured
+         end if
+      else
+         ! Reset error flag to continue testing other properties:
+         errflg = 0
+      end if
+
       ! Mass mixing ratio:
       call const_props(index_ice)%is_mass_mixing_ratio(const_log, errflg,     &
            errmsg)
diff --git a/test/unit_tests/sample_scheme_files/temp_adjust.F90 b/test/unit_tests/sample_scheme_files/temp_adjust.F90
index 7b1d0cbb..70613ba1 100644
--- a/test/unit_tests/sample_scheme_files/temp_adjust.F90
+++ b/test/unit_tests/sample_scheme_files/temp_adjust.F90
@@ -29,7 +29,7 @@ subroutine temp_adjust_register(config_var, dyn_const, errflg, errmsg)
 
      allocate(dyn_const(1))
      call dyn_const(1)%instantiate(std_name="dyn_const", long_name='dyn const', &
-          units='kg kg-1', default_value=1._kind_phys,                          &
+          diag_name='DYNCONST', units='kg kg-1', default_value=1._kind_phys,    &
           vertical_dim='vertical_layer_dimension', advected=.true.,             &
           errcode=errflg, errmsg=errmsg)