diff --git a/bld/build-namelist b/bld/build-namelist
index dbc6adfc43..6ce53e55b3 100755
--- a/bld/build-namelist
+++ b/bld/build-namelist
@@ -750,6 +750,15 @@ if (not $waccm_phys) {
     add_default($nl, 'p_bot_for_radmrg');
 }
 
+# Check TUV-X configuration
+my $tuvx_active = $nl->get_value('tuvx_active');
+if ($tuvx_active =~ /$TRUE/io) {
+    my $tuvx_config = $cfg->get('tuvx');
+    if (!$tuvx_config) {
+	die "$ProgName - ERROR: must use -tuvx CAM configure flag \n";
+    }
+}
+
 # Solar irradiance
 
 # First check that solar_const and solar_irrad_data_file are not both defined
diff --git a/bld/config_files/definition.xml b/bld/config_files/definition.xml
index 7b552abd0a..75b8147078 100644
--- a/bld/config_files/definition.xml
+++ b/bld/config_files/definition.xml
@@ -59,6 +59,9 @@ Option to turn on waccmx thermosphere/ionosphere extension: 0 => no, 1 => yes
 <entry id="ext_co2_cool" valid_values="0,1" value="0">
 Option to turn on extended non-LTE CO2 cooling: 0 => no, 1 => yes
 </entry>
+<entry id="tuvx" valid_values="0,1" value="0">
+Option to build TUV-X library: 0 => no, 1 => yes
+</entry>
 <entry id="ionosphere" valid_values="none,wxie" value="none">
 Ionosphere model used in WACCMX.
 </entry>
diff --git a/bld/configure b/bld/configure
index f1447e2829..b91355f2ab 100755
--- a/bld/configure
+++ b/bld/configure
@@ -107,6 +107,7 @@ OPTIONS
      -psubcols <n>      Maximum number of sub-columns in a run - set to 1 if not using sub-columns (default)
      -rad <name>        Specify the radiation package [rrtmg | rrtmgp | rrtmgp_gpu | camrt]
      -silhs             Switch on SILHS.
+     -tuvx              Switch to build TUV-X library
      -usr_mech_infile   Path and file name of the user supplied chemistry mechanism file.
      -waccm_phys        Switch enables the use of WACCM physics in any chemistry configuration.
                         The user does not need to set this if one of the waccm chemistry options
@@ -305,6 +306,7 @@ GetOptions(
     "waccm_phys"                => \$opts{'waccm_phys'},
     "waccmx"                    => \$opts{'waccmx'},
     "ext_co2_cool"              => \$opts{'ext_co2_cool'},
+    "tuvx"                      => \$opts{'tuvx'},
 )  or usage();
 
 # Give usage message.
@@ -717,6 +719,12 @@ if (defined $opts{'ext_co2_cool'}) {
 }
 my $ext_co2_cool = $cfg_ref->get('ext_co2_cool');
 
+# TUV-x option
+if (defined $opts{'tuvx'}) {
+    $cfg_ref->set('tuvx', $opts{'tuvx'});
+}
+my $tuvx = $cfg_ref->get('tuvx');
+
 #-----------------------------------------------------------------------------------------------
 
 # Prognostic species package(s)
@@ -1788,6 +1796,11 @@ if ($ext_co2_cool) {
     $cfg_cppdefs .= ' -DEXT_CO2_COOL';
 }
 
+# TUV-X
+if ($tuvx) {
+    $cfg_cppdefs .= ' -DTUVX';
+}
+
 # PIO
 my $pio2_build = (defined $opts{'pio2'}) ? 1 : 0;
 
@@ -1864,7 +1877,7 @@ if ($cosp) {
       $ldflags .= " -L$cosp_libdir -lrttov13_wrapper -lrttov13_mw_scatt -lrttov13_brdf_atlas -lrttov13_emis_atlas -lrttov13_other -lrttov13_parallel -lrttov13_coef_io -lrttov13_hdf -lrttov13_main ";
       $cfg_ref->set('ldflags', $ldflags);
       print "Adding rttov libraries as dependencies in ldflags.\n";
-    }       
+    }
     # Create the COSP Makefile from a template and copy it into the cosp bld directory
     if ($print) { print "creating $cosp_libdir/Makefile\n"; }
     write_cosp_makefile("$cfgdir/../src/physics/cosp2/Makefile.in", "$cosp_libdir/Makefile");
diff --git a/cime_config/buildlib b/cime_config/buildlib
index 49a196b53d..3ff27782b1 100755
--- a/cime_config/buildlib
+++ b/cime_config/buildlib
@@ -6,7 +6,7 @@ create the cam library
 # pylint: disable=multiple-imports, wrong-import-position, wildcard-import
 # pylint: disable=unused-wildcard-import, bad-whitespace, too-many-locals
 # pylint: disable=invalid-name
-import sys, os, filecmp, shutil
+import sys, os, filecmp, shutil, re
 from glob import glob
 
 _CIMEROOT = os.environ.get("CIMEROOT")
@@ -232,60 +232,76 @@ def _build_tuvx(caseroot, libroot, bldroot):
 # Builds the TUV-x library and updates the case variables used to set the
 # include paths and linked libraries
 
-    with Case(caseroot) as case:
-        bldpath = os.path.join(bldroot, "tuv-x")
-        if not os.path.exists(bldpath):
-            os.makedirs(bldpath)
-        srcpath = os.path.abspath(os.path.join(case.get_value("SRCROOT"), \
-                                               "libraries", "tuv-x", ""))
-        logger.info("Building TUV-x in {} from source in {}\n".format(bldpath, srcpath))
-
-        arg_dict = _cmake_default_args(caseroot)
-        cmake_args = "-DCMAKE_VERBOSE_MAKEFILE=ON "
-        if case.get_value("MPILIB") != "mpi-serial":
-            cmake_args += "-DTUVX_ENABLE_MPI:BOOL=TRUE "
-        cmake_args += "-DCMAKE_BUILD_TYPE=Debug "
-        cmake_args += "-DCMAKE_Fortran_COMPILER=mpif90 "
-        cmake_args += "-DCMAKE_C_COMPILER=mpicc "
-        cmake_args += "-DCMAKE_CXX_COMPILER=mpicxx "
-        cmake_args += "-DCMAKE_Fortran_COMPILER_WORKS=1 "
-        cmake_args += "-DCMAKE_C_COMPILER_WORKS=1 "
-        cmake_args += "-DCMAKE_CXX_COMPILER_WORKS=1 "
-        if (case.get_value("MACH") == "izumi") :
-            cmake_args += f"-DCMAKE_PREFIX_PATH={arg_dict['NETCDF_PATH']} "
-            cmake_args += f"-DCMAKE_IGNORE_PATH={os.environ.get('PYTHONHOME')} "
-        if (case.get_value("MACH") == "izumi") and (case.get_value('COMPILER') == "nag") :
-            cmake_args += "-DCMAKE_Fortran_FLAGS='-C=all -g ' "
-        else :
-            cmake_args += f"-DCMAKE_Fortran_FLAGS='{arg_dict['FFLAGS']}' "
-        cmake_args += f"-DCMAKE_INSTALL_PREFIX='{libroot}' "
-        cmake_args += "-DTUVX_ENABLE_TESTS=OFF "
-        cmake_args += "-DTUVX_ENABLE_COVERAGE=OFF "
-        cmake_args += "-DTUVX_BUILD_CLI=OFF "
-        cmake_args += f"-DTUVX_INSTALL_INCLUDE_DIR='{_tuvx_include_dir(libroot)}' "
-        cmake_args += f"-DTUVX_INSTALL_MOD_DIR='{_tuvx_include_dir(libroot)}' "
-        cmake_args += srcpath
-
-        _run_cmd(f"cmake {cmake_args}", bldpath)
-        _run_cmd(case.get_value('GMAKE'), bldpath)
-        _run_cmd(f"{case.get_value('GMAKE')} install", bldpath)
-
-        # add TUV-x to include paths
-        incldir = os.environ.get('USER_INCLDIR')
-        if incldir is None:
-            incldir = ''
-        os.environ['USER_INCLDIR'] = incldir + \
-            f" -I{_tuvx_include_dir(libroot)} "
-
-        # create symlink to library in folder CIME expects libraries to be in
-        dst = os.path.join(libroot, "libtuvx.a")
-        if os.path.isfile(dst):
-            os.remove(dst)
-        os.symlink(_tuvx_lib_path(libroot), dst)
-        dst = os.path.join(libroot, "libyaml-cpp.a")
-        if os.path.isfile(dst):
-            os.remove(dst)
-        os.symlink(_yaml_cpp_lib_path(libroot), dst)
+    with Case(caseroot, read_only=False) as case:
+        config_opts = case.get_value("CAM_CONFIG_OPTS")
+
+        # Remove any TUV-x link options set by a previous build, so that
+        # re-building the case does not accumulate duplicate or stale
+        # options in CAM_LINKED_LIBS:
+        linked_libs = case.get_value("CAM_LINKED_LIBS",
+                                     subgroup="build_component_cam")
+        tuvx_link_opts = " -ltuvx -lyaml-cpp"
+        new_linked_libs = re.sub(r"\s*-ltuvx -lyaml-cpp", "", linked_libs)
+        if "-tuvx" in config_opts:
+            bldpath = os.path.join(bldroot, "tuv-x")
+            if not os.path.exists(bldpath):
+                os.makedirs(bldpath)
+            srcpath = os.path.abspath(os.path.join(case.get_value("SRCROOT"), \
+                                      "libraries", "tuv-x", ""))
+            logger.info("Building TUV-x in {} from source in {}\n".format(bldpath, srcpath))
+
+            arg_dict = _cmake_default_args(caseroot)
+            cmake_args = "-DCMAKE_VERBOSE_MAKEFILE=ON "
+            if case.get_value("MPILIB") != "mpi-serial":
+                cmake_args += "-DTUVX_ENABLE_MPI:BOOL=TRUE "
+            cmake_args += "-DCMAKE_BUILD_TYPE=Debug "
+            cmake_args += "-DCMAKE_Fortran_COMPILER=mpif90 "
+            cmake_args += "-DCMAKE_C_COMPILER=mpicc "
+            cmake_args += "-DCMAKE_CXX_COMPILER=mpicxx "
+            cmake_args += "-DCMAKE_Fortran_COMPILER_WORKS=1 "
+            cmake_args += "-DCMAKE_C_COMPILER_WORKS=1 "
+            cmake_args += "-DCMAKE_CXX_COMPILER_WORKS=1 "
+            cmake_args += "-DCMAKE_DISABLE_FIND_PACKAGE_yaml-cpp=1 "
+            if (case.get_value("MACH") == "izumi") :
+                cmake_args += f"-DCMAKE_PREFIX_PATH={arg_dict['NETCDF_PATH']} "
+            if (case.get_value("MACH") == "izumi") and (case.get_value('COMPILER') == "nag") :
+                cmake_args += "-DCMAKE_Fortran_FLAGS='-C=all -g ' "
+            else :
+                cmake_args += f"-DCMAKE_Fortran_FLAGS='{arg_dict['FFLAGS']}' "
+            cmake_args += f"-DCMAKE_INSTALL_PREFIX='{libroot}' "
+            cmake_args += "-DTUVX_ENABLE_TESTS=OFF "
+            cmake_args += "-DTUVX_ENABLE_COVERAGE=OFF "
+            cmake_args += "-DTUVX_BUILD_CLI=OFF "
+            cmake_args += f"-DTUVX_INSTALL_INCLUDE_DIR='{_tuvx_include_dir(libroot)}' "
+            cmake_args += f"-DTUVX_INSTALL_MOD_DIR='{_tuvx_include_dir(libroot)}' "
+            cmake_args += srcpath
+
+            _run_cmd(f"cmake {cmake_args}", bldpath)
+            _run_cmd(case.get_value('GMAKE'), bldpath)
+            _run_cmd(f"{case.get_value('GMAKE')} install", bldpath)
+
+            # add TUV-x to include paths
+            incldir = os.environ.get('USER_INCLDIR')
+            if incldir is None:
+                incldir = ''
+            os.environ['USER_INCLDIR'] = incldir + \
+                f" -I{_tuvx_include_dir(libroot)} "
+
+            # create symlink to library in folder CIME expects libraries to be in
+            dst = os.path.join(libroot, "libtuvx.a")
+            if os.path.isfile(dst):
+                os.remove(dst)
+            os.symlink(_tuvx_lib_path(libroot), dst)
+            dst = os.path.join(libroot, "libyaml-cpp.a")
+            if os.path.isfile(dst):
+                os.remove(dst)
+            os.symlink(_yaml_cpp_lib_path(libroot), dst)
+
+            # Add TUVX to CAM linked library list:
+            new_linked_libs = tuvx_link_opts.strip() + " " + new_linked_libs
+
+        if new_linked_libs != linked_libs:
+            case.set_value("CAM_LINKED_LIBS", new_linked_libs)
 
 ###############################################################################
 def _tuvx_include_dir(libroot):
diff --git a/cime_config/buildnml b/cime_config/buildnml
index 44238cf6e5..71ae4a44d1 100755
--- a/cime_config/buildnml
+++ b/cime_config/buildnml
@@ -65,7 +65,8 @@ def buildnml(case, caseroot, compname):
             "Gregorian calendar (modifier _cG) cannot be used with spinup compset \n  {}".format(COMPSET)
         )
 
-    tuvx_data_src = os.path.join(srcroot, "libraries", "tuv-x", "data")
+    if '-tuvx' in CAM_CONFIG_OPTS:
+        tuvx_data_src = os.path.join(srcroot, "libraries", "tuv-x", "data")
 
     testsrc = os.path.join(srcroot, "components", "cam")
     if os.path.exists(testsrc):
@@ -237,10 +238,11 @@ def buildnml(case, caseroot, compname):
                    shutil.copy(file1,file2)
 
         # Copy TUV-x data to rundir
-        dest_data = os.path.join(rundir, "data")
-        if os.path.exists(dest_data):
-            shutil.rmtree(dest_data)
-        shutil.copytree(tuvx_data_src, dest_data)
+        if '-tuvx' in CAM_CONFIG_OPTS:
+            dest_data = os.path.join(rundir, "data")
+            if os.path.exists(dest_data):
+                shutil.rmtree(dest_data)
+            shutil.copytree(tuvx_data_src, dest_data)
 
 ###############################################################################
 def _main_func():
diff --git a/cime_config/config_component.xml b/cime_config/config_component.xml
index d2ce3c980d..b15bc59949 100644
--- a/cime_config/config_component.xml
+++ b/cime_config/config_component.xml
@@ -230,7 +230,7 @@
   <entry id="CAM_LINKED_LIBS">
     <type>char</type>
     <valid_values></valid_values>
-    <default_value>-ltuvx -lyaml-cpp -lstdc++</default_value>
+    <default_value>-lstdc++</default_value>
     <group>build_component_cam</group>
     <file>env_build.xml</file>
     <desc>
diff --git a/cime_config/testdefs/testmods_dirs/cam/carma_mixed_sulfate/shell_commands b/cime_config/testdefs/testmods_dirs/cam/carma_mixed_sulfate/shell_commands
index e3d9ef9950..ed92990dcb 100644
--- a/cime_config/testdefs/testmods_dirs/cam/carma_mixed_sulfate/shell_commands
+++ b/cime_config/testdefs/testmods_dirs/cam/carma_mixed_sulfate/shell_commands
@@ -1,4 +1,4 @@
-./xmlchange CAM_CONFIG_OPTS=" -phys cam4 -rad rrtmg -chem waccm_ma_sulfur -carma mixed_sulfate"
+./xmlchange CAM_CONFIG_OPTS=" -phys cam4 -rad rrtmg -chem waccm_ma_sulfur -carma mixed_sulfate -tuvx"
 ./xmlchange ROF_NCPL=\$ATM_NCPL
 ./xmlchange GLC_NCPL=\$ATM_NCPL
 ./xmlchange RUN_STARTDATE="0001-01-01"
diff --git a/cime_config/testdefs/testmods_dirs/cam/outfrq9s_tuvx_waccm_ma_mam5/shell_commands b/cime_config/testdefs/testmods_dirs/cam/outfrq9s_tuvx_waccm_ma_mam5/shell_commands
index eb40ad83e0..f064e3e999 100644
--- a/cime_config/testdefs/testmods_dirs/cam/outfrq9s_tuvx_waccm_ma_mam5/shell_commands
+++ b/cime_config/testdefs/testmods_dirs/cam/outfrq9s_tuvx_waccm_ma_mam5/shell_commands
@@ -1,2 +1,3 @@
+./xmlchange --append CAM_CONFIG_OPTS="-tuvx"
 ./xmlchange ROF_NCPL=\$ATM_NCPL
 ./xmlchange GLC_NCPL=\$ATM_NCPL
diff --git a/cime_config/testdefs/testmods_dirs/cam/outfrq9s_waccm_ma_mam4/shell_commands b/cime_config/testdefs/testmods_dirs/cam/outfrq9s_waccm_ma_mam4/shell_commands
index 8cf20f57e4..25d6b327a1 100644
--- a/cime_config/testdefs/testmods_dirs/cam/outfrq9s_waccm_ma_mam4/shell_commands
+++ b/cime_config/testdefs/testmods_dirs/cam/outfrq9s_waccm_ma_mam4/shell_commands
@@ -1,2 +1,2 @@
 ./xmlchange ROF_NCPL=\$ATM_NCPL
-./xmlchange CAM_CONFIG_OPTS="-phys cam6 -age_of_air_trcs -chem waccm_ma_mam4 -ext_co2_cool"
+./xmlchange CAM_CONFIG_OPTS="-phys cam6 -age_of_air_trcs -chem waccm_ma_mam4 -ext_co2_cool -tuvx"
diff --git a/doc/ChangeLog b/doc/ChangeLog
index ee91c52211..c3cc2ea0fa 100644
--- a/doc/ChangeLog
+++ b/doc/ChangeLog
@@ -1,4 +1,84 @@
+===============================================================
+
+Tag name: cam6_4_182
+Originator(s): fvitt
+Date: 16 Jun 2026
+One-line Summary: Updates to CAM's build of TUV-X library
+Github PR URL: https://github.com/ESCOMP/CAM/pull/1577
+
+Purpose of changes (include the issue number and title text for each relevant GitHub issue):
+
+ Build TUV-X library only in cases where TUV-X is used.  Configure
+ switch -tuvx has been added to CAM_CONFIG_OPTS which activates
+ the build of the TUV-X library.
+
+ Address issues:
+  #1537: TUV-x build issue when users have Conda environments active
+  https://github.com/ESCOMP/CAM/issues/1570
+
+  #1570: TUV-x copies input files to run directory regardless of whether TUV-x is active
+  https://github.com/ESCOMP/CAM/issues/1570
+
+Describe any changes made to build system:
+ Changes TUV-X library build as described above
+
+Describe any changes made to the namelist: N/A
+
+List any changes to the defaults for the boundary datasets: N/A
+
+Describe any substantial timing or memory changes: N/A
+
+Code reviewed by: jimmielin cacraigucar
+
+List all files eliminated: N/A
+
+List all files added and what they do: N/A
+
+List all existing files that have been modified, and describe the changes:
+
+M       bld/build-namelist
+ - error out if tuvx_active is TRUE and not configured for TUV-X
+
+M       bld/config_files/definition.xml
+M       bld/configure
+ - add "-tuvx" configure switch -- define "TUVX" CPP def
+
+M       cime_config/buildlib
+ - build TUV-X lib only if "-tuvx" is included in CAM_CONFIG_OPTS
+
+M       cime_config/buildnml
+ - copy TUV-X input data to run directory only if "-tuvx" is included in CAM_CONFIG_OPTS
+
+M       cime_config/config_component.xml
+ - remove tuvx and yaml-cpp libs from default setting of CAM_LINKED_LIBS
+   -- buildlib will add these only only if cam is configured for tuvx
 
+M       cime_config/testdefs/testmods_dirs/cam/carma_mixed_sulfate/shell_commands
+M       cime_config/testdefs/testmods_dirs/cam/outfrq9s_tuvx_waccm_ma_mam5/shell_commands
+M       cime_config/testdefs/testmods_dirs/cam/outfrq9s_waccm_ma_mam4/shell_commands
+ -- append "-tuvx" to CAM_CONFIG_OPTS
+
+M       src/chemistry/mozart/mo_tuvx.F90
+ - use ifdefs to stub out the module for cases where TUV-X lib is not available
+
+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.
+
+derecho/intel/aux_cam: All PASS
+
+derecho/nvhpc/aux_cam: All PASS
+
+izumi/nag/aux_cam:
+  FAIL ERC_D_Ln9.f10_f10_mt232.FHIST_C5.izumi_nag.cam-outfrq3s_subcol COMPARE_base_rest
+  - pre-existing failure -- see https://github.com/ESCOMP/CAM/issues/1514
+
+izumi/gnu/aux_cam: All PASS
+
+Summarize any changes to answers: bit-for-bit
+
+===============================================================
 ===============================================================
 
 Tag name: cam6_4_181
diff --git a/src/chemistry/mozart/mo_tuvx.F90 b/src/chemistry/mozart/mo_tuvx.F90
index 7644277f39..29c7d800eb 100644
--- a/src/chemistry/mozart/mo_tuvx.F90
+++ b/src/chemistry/mozart/mo_tuvx.F90
@@ -2,12 +2,18 @@
 ! Wrapper for TUV-x photolysis rate constant calculator
 !----------------------------------------------------------------------
 module mo_tuvx
-
+   use shr_kind_mod, only : r8 => shr_kind_r8, cl=>shr_kind_cl
+   use spmd_utils, only : is_main_task => masterproc
+   use spmd_utils, only : main_task_id => masterprocid
+   use cam_abortutils, only : endrun
+   use cam_logfile, only : iulog ! log info output unit
+   use spmd_utils, only : mpicom, mpi_character, mpi_integer, mpi_logical, mpi_success
+   use ppgrid, only : pver, &  ! number of vertical layers
+                      pverp, & ! number of vertical interfaces (pver + 1)
+                      pcols    ! maximum number of columns
+#ifdef TUVX
    use musica_map,              only : map_t
    use musica_string,           only : string_t
-   use ppgrid,                  only : pver, & ! number of vertical layers
-                                       pverp   ! number of vertical interfaces (pver + 1)
-   use shr_kind_mod,            only : r8 => shr_kind_r8, cl=>shr_kind_cl
    use tuvx_core,               only : core_t
    use tuvx_grid_from_host,     only : grid_updater_t
    use tuvx_profile_from_host,  only : profile_updater_t
@@ -19,13 +25,8 @@ module mo_tuvx
    use ppgrid, only : pcols ! maximum number of columns
    use radconstants, only : get_sw_spectral_boundaries
    use cam_history, only : fieldname_len, horiz_only, addfld, outfld !, add_default
-   use spmd_utils, only : is_main_task => masterproc
-   use spmd_utils, only : main_task_id => masterprocid
-   use spmd_utils, only : mpicom, mpi_character, mpi_integer, mpi_logical, mpi_success
-   use cam_abortutils, only : endrun
-   use cam_logfile, only : iulog ! log info output unit
    use shr_const_mod, only : pi => shr_const_pi
-
+#endif
    implicit none
 
    private
@@ -38,6 +39,7 @@ module mo_tuvx
    public :: tuvx_finalize
    public :: tuvx_active
 
+#ifdef TUVX
    ! Inidices for grid updaters
    integer, parameter :: NUM_GRIDS = 2             ! number of grids that CAM will update at runtime
    integer, parameter :: GRID_INDEX_HEIGHT     = 1 ! Height grid index
@@ -140,21 +142,21 @@ module mo_tuvx
       integer :: index_                      ! index of the photolysis rate constant from TUV-x
    end type diagnostic_t
    type(diagnostic_t), allocatable :: diagnostics(:)
-
+#endif
    ! namelist options
    character(len=cl) :: tuvx_config_path = 'NONE'  ! absolute path to TUVX configuration file
    logical, protected :: tuvx_active = .false.
-
-  integer :: swaertau_idx   = -1       ! shortwave aerosol extinction optical depth. tau
-  integer :: swaertauw_idx  = -1       ! shortwave aerosol extinction optical depth * single scattering albedo. tau*w
-  integer :: swaertauwg_idx = -1       ! shortwave aerosol extinction optical depth * single scattering albedo * asymmetry parameter. tau*w*g
-  integer :: swcldtau_idx   = -1       ! shortwave cloud extinction optical depth. tau
-  integer :: swcldtauw_idx  = -1       ! shortwave cloud extinction optical depth * single scattering albedo. tau*w
-  integer :: swcldtauwg_idx = -1       ! shortwave cloud extinction optical depth * single scattering albedo * asymmetry parameter. tau*w*g
-  type (interp_type) :: interp_wgts
-  real(r8) :: rrtmg_wavelength(nswbands-1)
-  integer :: nwave
-
+#ifdef TUVX
+   integer :: swaertau_idx   = -1       ! shortwave aerosol extinction optical depth. tau
+   integer :: swaertauw_idx  = -1       ! shortwave aerosol extinction optical depth * single scattering albedo. tau*w
+   integer :: swaertauwg_idx = -1       ! shortwave aerosol extinction optical depth * single scattering albedo * asymmetry parameter. tau*w*g
+   integer :: swcldtau_idx   = -1       ! shortwave cloud extinction optical depth. tau
+   integer :: swcldtauw_idx  = -1       ! shortwave cloud extinction optical depth * single scattering albedo. tau*w
+   integer :: swcldtauwg_idx = -1       ! shortwave cloud extinction optical depth * single scattering albedo * asymmetry parameter. tau*w*g
+   type (interp_type) :: interp_wgts
+   real(r8) :: rrtmg_wavelength(nswbands-1)
+   integer :: nwave
+#endif
 !================================================================================================
 contains
 !================================================================================================
@@ -163,7 +165,7 @@ module mo_tuvx
    ! registers fields in the physics buffer
    !-----------------------------------------------------------------------
    subroutine tuvx_register( )
-
+#ifdef TUVX
       use mo_jeuv,        only : nIonRates
       use physics_buffer, only : pbuf_add_field, dtype_r8
       use ppgrid,         only : pcols ! maximum number of columns
@@ -190,7 +192,7 @@ subroutine tuvx_register( )
       call pbuf_add_field('SWCLDTAU',   'global',dtype_r8,(/pcols,pver,nswbands/), swcldtau_idx)   ! shortwave tau
       call pbuf_add_field('SWCLDTAUW',  'global',dtype_r8,(/pcols,pver,nswbands/), swcldtauw_idx)  ! shortwave tau * w
       call pbuf_add_field('SWCLDTAUWG', 'global',dtype_r8,(/pcols,pver,nswbands/), swcldtauwg_idx) ! shortwave tau * w * g
-
+#endif
    end subroutine tuvx_register
 
 !================================================================================================
@@ -200,7 +202,7 @@ end subroutine tuvx_register
    !-----------------------------------------------------------------------
    subroutine tuvx_readnl(nlfile)
 
-      use namelist_utils, only : find_group_name
+     use namelist_utils, only : find_group_name
 
       character(len=*), intent(in)  :: nlfile  ! filepath for file containing namelist input
 
@@ -235,6 +237,7 @@ subroutine tuvx_readnl(nlfile)
       call mpi_bcast(tuvx_active,      1,                     mpi_logical,   main_task_id, mpicom, ierr)
       if (ierr /= mpi_success) call endrun(subname//': mpi_bcast error : tuvx_active')
 
+#ifdef TUVX
       if (tuvx_active .and. tuvx_config_path == 'NONE') then
          call endrun(subname // ' : must set tuvx_config_path when TUV-X is active')
       end if
@@ -243,7 +246,11 @@ subroutine tuvx_readnl(nlfile)
          write(iulog,*) 'tuvx_readnl: tuvx_config_path = ', trim(tuvx_config_path)
          write(iulog,*) 'tuvx_readnl: tuvx_active = ', tuvx_active
       end if
-
+#else
+      if (tuvx_active .or. tuvx_config_path /= 'NONE') then
+         call endrun(subname // ' : use -tuvx configure CAM option to build TUV-X library')
+      end if
+#endif
    end subroutine tuvx_readnl
 
 !================================================================================================
@@ -252,7 +259,10 @@ end subroutine tuvx_readnl
    ! Initializes TUV-x for photolysis calculations
    !-----------------------------------------------------------------------
    subroutine tuvx_init( photon_file, electron_file, max_solar_zenith_angle, pbuf2d )
-
+      use physics_buffer,          only : physics_buffer_desc
+      use physics_buffer,          only : pbuf_set_field
+      use ppgrid,                  only : pcols ! maximum number of columns
+#ifdef TUVX
       use infnan,                  only : nan, assignment(=)
       use mo_chem_utls,            only : get_spc_ndx, get_inv_ndx
       use mo_jeuv,                 only : neuv ! number of extreme-UV rates
@@ -262,9 +272,6 @@ subroutine tuvx_init( photon_file, electron_file, max_solar_zenith_angle, pbuf2d
                                           musica_mpi_pack, &
                                           musica_mpi_unpack
       use musica_string,           only : string_t, to_char
-      use physics_buffer,          only : physics_buffer_desc
-      use physics_buffer,          only : pbuf_set_field
-      use ppgrid,                  only : pcols ! maximum number of columns
       use solar_irrad_data,        only : has_spectrum
       use tuvx_grid,               only : grid_t
       use tuvx_grid_warehouse,     only : grid_warehouse_t
@@ -273,13 +280,14 @@ subroutine tuvx_init( photon_file, electron_file, max_solar_zenith_angle, pbuf2d
       use time_manager,            only : is_first_step
 
       use physics_buffer,  only: pbuf_get_index
-
+#endif
       character(len=*), intent(in) :: photon_file   ! photon file used in extended-UV module setup
       character(len=*), intent(in) :: electron_file ! electron file used in extended-UV module setup
       real(r8),         intent(in) :: max_solar_zenith_angle ! cutoff solar zenith angle for
                                                              !    photo rate calculations [degrees]
       type(physics_buffer_desc), pointer :: pbuf2d(:,:) ! Physics buffer
 
+#ifdef TUVX
       character(len=*), parameter :: my_name = "TUV-x wrapper initialization"
       class(core_t), pointer :: core
       character, allocatable :: buffer(:)
@@ -551,7 +559,7 @@ subroutine tuvx_init( photon_file, electron_file, max_solar_zenith_angle, pbuf2d
       deallocate(wc)
 
       if( is_main_task ) call log_initialization( labels )
-
+#endif
    end subroutine tuvx_init
 
 !================================================================================================
@@ -564,13 +572,13 @@ subroutine tuvx_timestep_init( )
       integer :: i_thread
 
       if( .not. tuvx_active ) return
-
+#ifdef TUVX
       do i_thread = 1, size( tuvx_ptrs )
          associate( tuvx => tuvx_ptrs( i_thread ) )
             call set_et_flux( tuvx )
          end associate
       end do
-
+#endif
    end subroutine tuvx_timestep_init
 
 !================================================================================================
@@ -614,6 +622,7 @@ subroutine tuvx_get_photo_rates( pbuf, ncol, lchnk, height_mid, &
       real(r8), intent(in)    :: liquid_water_content(ncol,pver)    ! liquid water content (kg/kg)
       real(r8), intent(inout) :: photolysis_rates(ncol,pver,phtcnt) ! photolysis rate
                                                                     !   constants (1/s)
+#ifdef TUVX
       integer :: ipht, k, idose
       integer  :: i_col   ! column index
       integer  :: i_level ! vertical level index
@@ -797,7 +806,7 @@ subroutine tuvx_get_photo_rates( pbuf, ncol, lchnk, height_mid, &
          end do
          call outfld('CPE_jO3b', cpe_jo3_b(:ncol,:), ncol, lchnk )
       end if
-
+#endif
    end subroutine tuvx_get_photo_rates
 
 !================================================================================================
@@ -806,7 +815,7 @@ end subroutine tuvx_get_photo_rates
    ! Cleans up memory associated with TUV-x calculators
    !-----------------------------------------------------------------------
    subroutine tuvx_finalize( )
-
+#ifdef TUVX
       integer :: i_core, i_diag
 
       if( allocated( tuvx_ptrs ) ) then
@@ -828,9 +837,9 @@ subroutine tuvx_finalize( )
       if (allocated(dose_rate_hist_name)) then
          deallocate(dose_rate_hist_name)
       end if
-
+#endif
    end subroutine tuvx_finalize
-
+#ifdef TUVX
 !================================================================================================
 !================================================================================================
 !
@@ -2028,7 +2037,7 @@ subroutine calculate_jno( solar_zenith_angle, et_flux, fixed_species_conc, speci
       jno(:pver) = work_jno(:pver)
 
    end subroutine calculate_jno
-
+#endif
 !================================================================================================
 
 end module mo_tuvx