12. Appendices¶
12.1. The configure utility¶
12.1.1. Arguments to configure¶
All configuration options can be specified using command line arguments to
CAM’s configure script (a Perl script). Options not specified on the
command line will be set to default values which are either hard-coded, or
come from the definition file
components/cam/bld/config_files/definition.xml. Those that depend on
the values of other options are set by logic contained in configure.
The user is able to pass arguments to CAM’s configure by issuing an
xlmchange command for CAM_CONFIG_OPTS. It is important to use the
--append option if a compset’s settings are to be maintained.
The options may all be specified with either one or two leading dashes,
e.g., -help or --help. A consequence of allowing long names with
single leading dashes is that the few options that can be expressed as
single letter switches may not be bundled, e.g., -h -s -v may NOT
be expressed as -hsv.
User supplied values are denoted in angle brackets “<>”. Any value that contains white-space must be quoted. For options that can be set from small set of legal values, those values are given as a vertical bar separated list.
The arguments to configure are:
-[no]age_of_air_trcs
Switch on [off] age of air tracers. Default: on for waccm_phys, otherwise off.
-analytic_ic Enables the (namelist controlled) dycore testing infrastructure.
-aquaplanet Switch on aqua-planet mode.
-build_chem_proc Switch forces the build of the chemistry preprocessor (primarily for testing).
-cache <file> Name of output cache file which contains all configuration parameters
set by configure script.
Default: config_cache.xml
-cachedir <file> Name of directory where output cache file is written.
Default: current working directory
-camiop Configure CAM to generate an IOP file that can be used to drive SCAM.
This switch only works with the Eulerian dycore.
-carma <name> Build CAM with specified CARMA microphysics model
[ none (disabled) | bc_strat (Stratospheric Black Carbon) |
cirrus (Cirrus Clouds) | cirrus_dust (Cirrus Clouds with dust) |
dust (Dust) | meteor_impact (Meteor Impact) | meteor_smoke (Meteor Smoke) |
mixed_sulfate (Meteor Smoke and Sulfate) | pmc (Polar Mesospheric Clouds) |
pmc_sulfate (PMC and Sulfate) | sea_salt (Sea Salt) |
sulfate (Sulfate Aerosols) | tholin (early earth haze) |
test_detrain (Detrainment) | test_growth (Particle Growth) |
test_passive (Passive Dust) | test_radiative (Radiatively Active Dust) |
test_swelling (Sea Salt) | test_tracers (Asian Monsoon) |
test_tracers2 (Guam)].
Default: none.
-chem <name> Build CAM with specified prognostic chemistry package
[ trop_mam3 | trop_mam4 | trop_mam7 | trop_mozart | trop_strat_mam4_vbs |
trop_bam | trop_ghg | waccm_ma | waccm_mad_mam4 | waccm_ma_mam4 |
waccm_ma_sulfur | waccm_sc | waccm_sc_mam4 | waccm_tsmlt |
waccm_tsmlt_mam4 | waccm_tsmlt_sulfur | super_fast_llnl |
super_fast_llnl_mam3 | terminator | none ].
Default: trop_mam4 for cam6, trop_mam3 for cam5,
otherwise none.
-[no]clubb_sgs Switch on [off] CLUBB_SGS. Default: on for cam6, otherwise off.
-clubb_opts <list> Comma separated list of CLUBB options to turn on.
[clubb_do_adv (Advect CLUBB moments)]
-co2_cycle Switch to turn on the carbon cycle code (adds 4 advected constituents)
-cosp Enable the COSP simulator.
-dyn <name> Dynamical core option.
[eul (Eulerian) | fv (Finite Volume)].
-edit_chem_mech Invokes CAMCHEM_EDITOR to allow the user to edit the chemistry mechanism file.
-help [or -h] Print usage to STDOUT.
-hgrid <name> Specify horizontal grid. For spectral grids use nlatxnlon where
nlat and nlon are the number of latitude and longitude grid
points respectively in the global Gaussian grid (e.g., T42 is
specified 64x128). For FV grids use dlatxdlon where dlat and
dlon are the grid cell size in degrees for latitude and longitude
respectively (e.g., 1.9x2.5).
-ionosphere Ionophere module used in WACCMX [ none | wxi | wxie ].
Default: none
-macrophys <name> Override the default macrophysics set by the physics package
[rk | park | clubb_sgs | spcam_sam1mom | spcam_m2005]
Defaults:
clubb_sgs if cam6
park if cam6 and noclubb_sgs, or cam5
rk if cam3 or cam4
-max_n_rad_cnst <n> Maximum number of constituents that are either radiatively
active, or in any single diagnostic list for the radiation.
Default: 30
-microphys <name> Override the microphysics set by the physics package
[mg1 | mg2 | rk | spcam_m2005 | spcam_sam1mom].
Defaults:
mg2 if cam6
mg1 if cam5
rk if cam3 or cam4
-nadv <n> Override the total number of advected species set by the
physics and chemistry packages.
-nadv_tt <n> Set number of advected test tracers.
Default: 0
-nlev <n> Override the number of levels set by the physics or chemistry package.
Default:
32 if cam6
30 if cam5, simple physics, or spcam_m2005
26 if cam3, cam4, or spcam_sam1mom
66 if waccm and cam4
70 if waccm and cam5 or cam6
81 if waccmx
126 if waccmx and ionosphere is wxie
-offline_drv <name> Specify offline unit driver.
[rad (PORT)]
-offline_dyn Enable offline driver for FV dycore.
-ocn <name> Allows build system to inform CAM which ocean component is being used.
This information is stored in the cache file and used by build-namelist
for selecting the default values of some tuning parameters.
[docn | som | socn | aquaplanet | pop].
-pbl <name> Override the PBL scheme set by the physics package.
[clubb_sys | uw | hb | spcam_sam1mom | spcam_m2005].
Default PBL schemes:
clubb_sgs if cam6
uw if cam5
hb if cam3 or cam4
spacm_m2005 if the physics package is spcam_m2005
spacm_sam1mom if the physics package is spcam_sam1mom
-pcols <n> Maximum number of columns in a chunk.
Default: 16, or if SCAM mode then 1.
-pergro Switch enables building CAM for perturbation growth tests.
Only valid with cam3 or cam4 physics.
-phys <name> Physics option.
[cam3 | cam4 | cam5 | cam6 | held_suarez | adiabatic | kessler |
spcam_sam1mom | spcam_m2005].
Default: cam6, or if waccmx then cam4.
-prog_species <list>Comma-separate list of prognostic mozart species packages.
Currently available: DST,SSLT,SO4,GHG,OC,BC,CARBON16
-psubcols <n> Maximum number of sub-columns in a grid column.
Default: 1
-rad <name> Override the radiation scheme set by the physics package.
[rrtmg | camrt].
Default radiation scheme:
rrtmg if cam5, cam6, or spcam_m2005
camrt if cam3, cam4, or spcam_sam1mom
-scam Compiles model in single column (SCAM) mode.
Only works with Eulerian dycore.
-silent [or -s] Turns on silent mode - only fatal messages issued.
-[no]smp Switch on [off] SMP parallelism (OpenMP)
-spcam_clubb_sgs Turn on the SPCAM version of CLUBB
-spcam_nx <n> SPCAM x-grid. (note the CRM requires spcam_nx to be greater
than or equal to 4)
Default: 4
-spcam_ny <n> SPCAM y-grid.
Default: 1
-spcam_dx <n> SPCAM horizontal grid spacing.
-spcam_dt <n> SPCAM timestep in seconds.
-[no]spmd Switch on [off] SPMD parallelism (MPI).
-unicon Switch to turn on the UNICON scheme.
-usr_mech_infile Absolute pathname of the user supplied chemistry mechanism file.
-usr_src <dir1>[,<dir2>[,<dir3>[...]]]
Directories containing user source code. Note that these
directories will also be searched for modified versions of the
files needed by the build-namelist script, e.g., the
namelist definition, defaults, and use case files.
-verbose [or -v] Turn on verbose echoing of settings made by configure.
-version Echo the tag name of the CAM component.
-waccm_phys Switch enables the use of WACCM physics in any chemistry configuration.
Default: off unless one of the waccm chemistry options is chosen.
-waccmx Build CAM/WACCM with WACCM upper Thermosphere/Ionosphere extended package.
-zmconv_org Enable sub-grid scale convective organization for the ZM deep
convective scheme based on Mapes and Neale (2011)
12.2. The build-namelist utility¶
The build-namelist utility produces namelists for the CAM
component (in the file atm_in), and namelists for the control of dry
deposition which is shared by CAM and CLM (in the file drv_flds_in).
The task of constructing a correct namelist is extremely complex
due to the large number of configurations supported by CAM. Editing
namelists by hand is a fragile process due to the number of variables that
need to be set, and to the many interdependencies among them. We strongly
discourage editing namelists by hand. All customizations of the CAM
namelist are possible by making use of the build-namelist command line
options. The most common way to do this is by adding customized variables
to the user_nl_cam file which is then processed by build-namelist
via the -infile option.
Some of the important features of build-namelist are:
- All valid namelist variables are known to
build-namelist. So an invalid variable specified by the user (supplied either by the-infileor-namelistoptions) will causebuild-namelistto fail with an error message telling which namelist variable is invalid. This is a big improvement over a runtime failure caused by an invalid variable which typically gives no hint as to which variable caused the problem. - In addition to knowing all valid variable names and their types,
build-namelistalso knows which namelist group each variable belongs to. This means that the user only needs to specify variable names tobuild-namelistand not the group names. The-infileand-namelistoptions still require valid namelist syntax as input, but the group name is ignored. So all variables can be put in a single group with an arbitrary name, for example, “&xxx … /” where “xxx” is the namelist group name. - Since
build-namelistknows all namelist variables specified by the user it is able to do consistency checking. In general however,build-namelistassumes that the user is the expert and will not override a user specification unless there is a major inconsistency, for example if variables have been set to use parameterizations which can not be run at the same time. - All configurations have namelist variables that must be specified,
and
build-namelisthas a mechanism to provide default values for these variables. When an appropriate default value cannot be found thenbuild-namelistwill fail with an informative message. - When running a configuration for the first time there are often many
input datasets that may not be in the local input data directory. In
order to facilitate getting the required datasets
build-namelisthas an option,-test, that can be used to produce a complete list of required datasets and report status of whether or not they are present in the local filesystem. This list can then be used to obtain the needed datasets from the CESM SVN input data repository. - One required input for
build-namelistis a configuration cache file produced by a previous invocation ofconfigure(config_cache.xmlby default).build-namelistlooks at this file to determine the features of the CAM executable, such as the dynamical core and horizontal resolution, that affect the default specifications for namelist variables. The default values themselves are specified in the filecomponents/cam/bld/namelist_files/namelist_defaults_cam.xml, and in the use case files located in the directorycomponents/cam/bld/namelist_files/use_cases/. - The other required input for
build-namelistis the root directory for the input datasets. This is required since nearly all input files must be specified using absolute filepaths, but the defaults are stored as filepaths which are relative to the root directory. It is expected that the actual location of the root directory is something that will be resolved at runtime. The way this is done is to either specify it using the-csmdataargument, or to set the environment variableCSMDATA.
The methods for setting the values of namelist variables, listed from highest to lowest precedence, are:
- using the
-namelistoption, - setting values in a file specified by
-infile, - specifying a
-use_caseoption, - setting values in the namelist defaults file.
- The first three of these methods for specifying namelist variables are the ones available to the user without requiring code modification. Any namelist variable recognized by CAM can be modified using method 1 or 2. The final two methods represent defaults that are hard coded as part of the code base.
12.2.1. Arguments to build namelist¶
The options may all be specified with either one or two leading dashes,
e.g., -help or --help. A consequence of allowing long names with
single leading dashes is that the few options that can be expressed as
single letter switches may not be bundled, e.g., -h -s -v may NOT
be expressed as -hsv.
User supplied values are denoted in angle brackets “<>”. Any value that contains white-space must be quoted. For options that can be set from small set of legal values, those values are given as a vertical bar separated list.
-config <filepath> Read the given configuration cache file to determine the configuration
of the CAM executable.
Default: "config_cache.xml".
-csmdata <dir> Root directory of CESM input data.
Can also be set by using the CSMDATA environment variable.
-dir <directory> Directory where output namelist files will be written,
i.e., atm_in, and drv_flds_in.
Default: current working directory.
-help [or -h] Print usage to STDOUT.
-ignore_ic_date Ignore the date of the initial condition files
when determining the default.
-ignore_ic_year Ignore just the year part of the date of the initial condition files
when determining the default.
-infile <filepath> Specify a file containing namelists to read values from.
-inputdata <filepath> Writes out a list containing pathnames for required input datasets to
the specified filepath.
-namelist <namelist> Specify namelist settings directly on the commandline by supplying
a string containing FORTRAN namelist syntax, e.g.,
-namelist "&camexp state_debug_checks=.true. /"
-ntasks <n> Specify the number of MPI tasks being used by the run. This is used
to set a default decomposition for the FV dycore only (npr_yz).
-silent [-s] Turns on silent mode - only fatal messages issued.
-test Enable checking that input datasets exist on local filesystem.
-use_case Specify a use case.
-verbose [or -v] Turn on verbose echoing of informational messages.
-version Echo the tag name of the CAM component.
12.2.2. CAM Namelist variables¶
Follow link for a searchable (or browsable) page containing all CAM namelist variables