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7.1 Example 1: Offline initial run, one day, global

When the model is run in offline mode using a pre-existing surface dataset, the minimum namelist parameters are: CASEID, NSREST, NESTEP or NELAPSE, FSURDAT, FPFTCON, OFFLINE_ATMDIR, START_YMD, and DTIME. If FSURDAT is blank, a surface dataset will be generated at run time and additional variables need to be specified (see section 4.2 and Examples 5 and 6). All other namelist parameters will be set to default values. The following gives an example of a simple namelist.

 &clmexp 
 CASEID         =  'test01'
 NSREST         =   0 
 NESTEP         =  -1 
 FSURDAT        =  '$CSMDATA/srfdata/cam/clms_64x128_T42_c020514.nc'
 FINIDAT        =  ' '
 FPFTCON        =  '$CSMDATA/pftdata/pft-physiology' 
 FRIVINP_RTM    =  '$CSMDATA/rtmdata/rdirc.05'
 OFFLINE_ATMDIR =  '$CSMDATA/NCEPDATA' 
 START_YMD      =  19971231
 DTIME          =  1800
 HIST_NHTFRQ(1) =  -24
 /


CASEID = 'test01'
Case identifier which distinguishes this particular simulation from another. The string in CASEID shows up in the names of history, restart, and initial files, in the restart pointer file name (see Example 2) and in the Mass Store pathname where history and restart files are placed if the Mass Store is used. In a branch run, the user must specify a new CASEID.


NSREST = 0
Requests an initial run, as opposed to a restart or a branch run. An initial run does not require the use of an initial input datafile (FINIDAT). If none is provided, the model uses non spun-up initialization provided in the code (see src/main/iniTimeVar.F90).


NESTEP = -1
Specifies the run's ending time to be at the end of day 1. Since NESTEP overrides any value given to NELAPSE, NELAPSE has been omitted in this example.


FSURDAT = '$CSMDATA/srfdata/cam/clms_64x128_T42_c020514.nc'
Specifies the name of the surface data input file. This T42 surface dataset can be used both in cam and offline mode. The model resolution, (i.e. parameters lsmlon and lsmlat) must be compatible with the resolution of FSURDAT. If the filename appeared without a path specifying its exact location, the file would be expected in the executable directory, defined by the environment variable $MODEL_EXEDIR.


FINIDAT = ' ' Specifies that model-specified initial values be used.


FPFTCON = '$CSMDATA/pftdata/pft-physiology'
Specifies a file with PFT (Plant Functional Type) information.


FRIVINP_RTM = '$CSMDATA/rtmdata/rdirc.05'
Specifies the input file required for the operation of RTM (the River Transport Model of Branstetter et al). By default, RTM will operate at half degree horizontal resolution and will be invoked every 3 hours, where the RTM input fluxes are averaged over the 3 hour period. If the user wants the RTM scheme to be invoked every timestep, RTM_NSTEPS should be set to 1. If the user wants the RTM scheme to operate at a different frequency than once every 3 hours, RTM_NSTEPS should be set to the desired value. Use of RTM is activated in the jobscript.csh with the C pre-processor (cpp) directive #define RTM in the header file preproc.h (see 3.1.3).


OFFLINE_ATMDIR = '$CSMDATA/NCEPDATA'
Specifies the location of the atmospheric driver data set. Such a data set is required for the model to run in offline mode.


START_YMD = 19971231
Specifies the base date of the simulation and must be compatible with the atmospheric input data. For example, START_YMD = 19971231 will use the atmospheric input file 1997-12.nc. In a restart or branch run, START_YMD need not be changed, as long as it refers to a date earlier than the date of restart or branch.


DTIME = 1800
Specifies the simulation's timestep in seconds. In offline mode, the model can handle a timestep of up to 3600 seconds.


HIST_NHTFRQ(1) = -24
Primary history files and restart files will be produced in the executable directory and will be written every 24 hours.


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Next: 7.2 Example 2: Restart Up: 7 Offline Mode Namelist Previous: 7 Offline Mode Namelist   Contents
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