operating system - DO NOT EDIT UNLESS for userdefined machine - ignored once Macros has been created  

machine compiler (must match one the supported compilers) - ignored once Macros has been created . 
Set in $CCSMROOT/scripts/ccsm_utils/Machines/config_machines.xml for each machine.

Machine compiler (must match one the supported compilers) . 
Set in $CCSMROOT/scripts/ccsm_utils/Machines/config_machines.xml for each supported machine.
Must be explicitly set in env_build.xml for userdefined machine.

supported mpi libraries for target machine - set in config_machines.xml - (DO NOT EDIT) . 
Set in $CCSMROOT/scripts/ccsm_utils/Machines/config_machines.xml for each supported machine.
Must be explicitly set in env_build.xml for userdefined machine.

mpi library (must match one of the supported libraries) - ignored once Macros has been created . 
Set in $CCSMROOT/scripts/ccsm_utils/Machines/config_machines.xml for each supported machine.
Must be explicitly set in env_build.xml for userdefined machine.

PIO configure options, see PIO configure utility for details

case executable root directory (executable is $EXEROOT/cesm.exe, component libraries are in $EXEROOT/bld) . 
The CESM executable root directory.  This is where the model builds
its executable and by default runs the executable.  Note that EXEROOT
needs to have enough disk space for the experimental configuration
requirements. As an example, CESM can produce more than a terabyte of
data during a 100-year run, so you should set EXEROOT to scratch or
tmp space and frequently back up the data to a mass storage device
EXEROOT is set in CCSMROOT/scripts/ccsm_utils/Machines/config_machines.xml
for each supported machine.  Must explicitly set it in env_build.xml for a
userdefined machine.

email address of person (or group) that supports the build and port for this machine (do not edit)

calendar type
Valid Values: NO_LEAP,GREGORIAN 

use MCT or ESMF component interfaces
Valid Values: MCT,ESMF 

TRUE implies using the ESMF library specified by ESMF_LIBDIR or ESMFMKFILE
Valid Values: TRUE,FALSE 

TRUE implies turning on run and compile time debugging . 
Flag to turn on debugging for run time and compile time. 
If TRUE, compile-time debugging flags are activated that you can use to verify 
software robustness, such as bounds checking.
Important:: On IBM machines, floating point trapping is not activated for production 
runs (i.e., non-DEBUG), due to performance penalties associated with turning on these flags. 
The default is FALSE.
Valid Values: TRUE,FALSE 

TRUE implies always build model for openmp capability . 
If FALSE, component libraries are built with OpenMP capability only if 
the NTHREADS_ setting for that component is greater than 1 in env_mach_pes.xml.
If TRUE, the component libraries are always built with OpenMP capability. 
The default is FALSE.
Valid Values: TRUE,FALSE 

GNU make command

Number of processors for gmake

CAM configure options, see CAM configure utility for details . 
Provides option(s) for the CAM configure utility. 
CAM_CONFIG_OPTS are normally set as compset variables (e.g., -phys  cam3_5_1 -chem waccm_mozart) 
and in general should not be modified for supported compsets.  It is recommended that if you want 
to modify this value for your experiment, you should use your own user-defined
component sets via using create_newcase with a compset_file argument.

CAM dynamical core
Valid Values: eul,fv,homme 

Option to the CICE configure utility for the -mode argument (default is prognostic)
Valid Values: prognostic,prescribed,thermo_only 

CICE configure options, see CICE configure utility for details . 
Provides option(s) for the CLM configure utility.
CICE_CONFIG_OPTS are normally set as compset variables (e.g., -ntr_aero 3)
and in general should not be modified for supported compsets.  
It is recommended that if you want to modify this value for your experiment, 
you should use your own user-defined component sets via using create_newcase 
with a compset_file argument. 
This is an advanced flag and should only be used by expert users.

if false, user must set the CICE decomp, otherwise cesm_setup script sets it . 
This is for experts only - if CICE_AUTO_DECOMP is set to false, then
can manually set the values of CICE_BLCKX, CICE_BLCKY, CICE_MXBLCKS, 
CICE_DECOMPTYPE, and CICE_DECOMPSETTING
Valid Values: true,false 

Size of cice block in first horiz dimension (do not edit if CICE_AUTO_DECOMP is true) . 
This is for experts only - automatically set if CICE_AUTO_DECOMP is true,
to set this value, must first set CICE_AUTO_DECOMP to false 

Size of cice block in second horiz dimension (do not edit if CICE_AUTO_DECOMP is true) . 
This is for experts only - automatically set if CICE_AUTO_DECOMP is true,
to set this value, must first set CICE_AUTO_DECOMP to false 

Max number of cice blocks per processor (do not edit if CICE_AUTO_DECOMP is true) . 
This is for experts only - automatically set if CICE_AUTO_DECOMP is true,
to set this value, must first set CICE_AUTO_DECOMP to false 

cice block distribution type (do not edit if CICE_AUTO_DECOMP is true) . 
This is for experts only - automatically set if CICE_AUTO_DECOMP is true,
to set this value, must first set CICE_AUTO_DECOMP to false 

cice decomp setting for decomp type (do not edit if CICE_AUTO_DECOMP is true) . 
This is for experts only - automatically set if CICE_AUTO_DECOMP is true,
to set this value, must first set CICE_AUTO_DECOMP to false 

CLM configure options . Provides option(s) for the CLM configure utility.
CLM_CONFIG_OPTS are normally set as compset variables (e.g., -bgc cn)
and in general should not be modified for supported compsets.  
It is recommended that if you want to modify this value for your experiment, 
you should use your own user-defined component sets via using create_newcase 
with a compset_file argument. 
This is an advanced flag and should only be used by expert users.

Optional ocean submodel option.  Any one of: moby

Optional ocean tracers.  Valid values are Any combination of: iage cfc ecosys

Optional ocean tracers option.  Any one of: darwin quota mono

if false, user must set the POP decomp, otherwise cesm_setup script sets it
Valid Values: true,false 

Size of pop block in first horiz dimension (do not edit if POP_AUTO_DECOMP is true)

Size of pop block in second horiz dimension (do not edit if POP_AUTO_DECOMP is true)

Number of pop blocks in first horiz dimension (do not edit if POP_AUTO_DECOMP is true)

Number of pop blocks in second horiz dimension (do not edit if POP_AUTO_DECOMP is true)

Max number of pop blocks per processor (do not edit if POP_AUTO_DECOMP is true)

pop block distribution type (do not edit if POP_AUTO_DECOMP is true)

Status output: if TRUE, models have been built successfully. (DO NOT EDIT)
Valid Values: TRUE,FALSE 

Status: smp status of previous build, coded string. (DO NOT EDIT)

Status: smp status of current case, coded string (DO NOT EDIT)

Status: ninst status of previous build, coded string. (DO NOT EDIT)

Status: ninst status of current case, coded string (DO NOT EDIT)

Status: of prior build. (DO NOT EDIT)

case build directory (set automatically to $EXEROOT, - DO NOT EDIT)

case lib directory (set automatically to $EXEROOT/lib - DO NOT EDIT)

case lib include directory (set automatically to $EXEROOT/lib/include - DO NOT EDIT)

Operate on only a single point of the global grid  - DO NOT EDIT (for experts only)
Valid Values: TRUE,FALSE 

CESM grid - DO NOT EDIT (for experts only)

number of glc cells in i direction - DO NOT EDIT (for experts only) . 
Currently the GLC grid and GLC_NX and GLC_NY is assumed to be identical to the land grid.

number of glc cells in j direction - DO NOT EDIT (for experts only) . 
Currently the GLC grid and GLC_NX and GLC_NY is assumed to be
identical to the land grid.

atmosphere grid - DO NOT EDIT (for experts only)

number of atmosphere cells in i direction - DO NOT EDIT (for experts only)

number of atmosphere cells in j direction - DO NOT EDIT (for experts only)

land grid - DO NOT EDIT (for experts only)

number of land cells in i direction - DO NOT EDIT (for experts only)

number of land cells in j direction - DO NOT EDIT (for experts only)

ocn grid - DO NOT EDIT (for experts only)

number of ocn cells in i direction - DO NOT EDIT (for experts only)

number of ocn cells in j direction - DO NOT EDIT (for experts only)

ice grid (must equal ocn grid) - DO NOT EDIT (for experts only)

number of ice cells in i direction - DO NOT EDIT (for experts only)

number of ice cells in j direction - DO NOT EDIT (for experts only)

river runoff (rof) grid
Valid Values: rx1,r01,r05,null 

number of rof cells in i direction - DO NOT EDIT (for experts only)

number of rof cells in j direction - DO NOT EDIT (for experts only)