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Running CLM offline for a particular year

Now I have a real noob question.

If I want to run CLM offline for say 2003 using the I4804 compset . What are the things I need to change to make sure I am actually providing correct atm forcing data for the year 2003 run.

I know I must change the start_ymd in drv_in . I must als specify how many years I need to run.

I am confused about the datm_atm_in stream data namelist. Should I change year_align in the stream data :
from - clm_qian.T62.stream.Solar.txt 1 1948 2004 to clm_qian.T62.stream.Solar.txt 1948 1948 2004 ?

Is there any other change I must to to make sure this offline run is correct ?

Thank you
 

erik

Erik Kluzek
CSEG and Liaisons
Staff member
Hi Raj

First of all check this part of the manual out...

http://www.cesm.ucar.edu/models/cesm1.0/clm/models/lnd/clm/doc/UsersGuide/x1427.html#other_config

running with CLM_QIAN forcing you use DATM_CLMNCEP_YR_START, DATM_CLMNCEP_YR_END, DATM_CLMNCEP_YR_ALIGN to control which years the forcing data is run over. If running over JUST 2003 you want them to be 2003. You'll also want to set the CCSM_CO2 level to an appropriate level for 2003 (the default is probably close enough), and if running with CN you'll want to tell the Nitrogen-deposition to run for 2003.

See the *_ndep variables in the namelist-definition file for CLM

http://www.cesm.ucar.edu/models/ces...lm/bld/namelist_files/namelist_definition.xml

such as...

stream_year_first_ndep

As you pointed out you want your STARTDATE to be 2003-01-01 and you'll want to run for just a year.
 
Thanks for the reply,

I have read through the User's guide before , so for running the Qian et al 1948-2004 data over the year 2003

I should have :
DATM_CLMNCEP_YR_START - 1948
DATM_CLMNCEP_YR_END - 2004
DATM_CLMNCEP_YR_ALIGN- 2003


With other changes to the Co2 conc. and changes in the drv_in namelist.
Thank You,
Raj
 
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