The env_build.xml file sets variables that control various aspects of building the model executable. Most of the variables should not be modified by users. The variables that you can modify are discussed in more detail below.
The CCSM 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, CCSM 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.
The directory where the executable will be run. By default this is set
to $EXEROOT/run. RUNDIR allows you to keep the run
directory separate from the build directory.
Valid values are TRUE and FALSE. The default is FALSE.
If FALSE, the 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.
Flag to turn on debugging for run time and compile time. Valid values are TRUE, FALSE. The default is FALSE.
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.
Number of processors for gmake (integer). 0 < GMAKE_J < [number of
processors/node]. $GMAKE_J allows a faster build on multi-processor
machines. If the build fails in different places without other
changes, setting this to 1 may help.
A POP2-specific setting for turning on different ocean tracer modules. Valid values are any combination of: iage, cfc, ecosys.