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branch or hybrid run using CLM4.5 in CESM1.2.1

Hi,

I tried to use the compset CLM4.5 in CESM1.2.1 for a branch or hybrid run, but it doesn' work. When I tried to do cesm_setup, It shows that "rtm.buildnml.csh could not find restart file for branch or hybrid start". I think I should change RUN_REFCASE in env_run.xml, but I don't know how and where to put the restart file. Any one has some experience?

cheers,

Zichong

 
About the restart file. I know this is a rookie question. But I really want to know how you guys do with it? Spin it up yourself or download it from somewhere? Thx. Zichong
 

santos

Member
I don't know about CLM specifically, but here is the documentation on setting up a hybrid/branch run:http://www.cesm.ucar.edu/models/cesm1.2/cesm/doc/usersguide/x1892.htmlThe restart files should go in the run directory ($RUNDIR). These files come from a previous model run (which can be one you do yourself or one someone else has done), since that's really the only reason to do a hybrid/branch run in the first place. If starting from an old case, I think that RTM can use CLM restart files, but I don't know what the requirements for that are.
 

erik

Erik Kluzek
CSEG and Liaisons
Staff member
This was an issue that was fixed with cesm1.2.2. Try using the later version and you should be OK.
 
I am currently using CESM1.2.1. I want to run a branch run from a old B_2000 run and I met the same problem. Can I fix it under version 1.2.1?Thanks.
 

erik

Erik Kluzek
CSEG and Liaisons
Staff member
This is a known bug documented in this bug report.http://bugs.cgd.ucar.edu/show_bug.cgi?id=1777 The fix is shown as the first comment in the report.
 
Hi Erik, this method doesn't work for me. I try to build a newcase using hybrid run and reference case will be one of my restart file. I have already put the restar file in the $RUN directory, but I still got the same error: rtm.buildnml.csh could not find restart file for branch or hybrid start.
Thanks!
Melody
 

Mengyao Xu

Mengyao Xu
New Member
Hi! I also encountered the same problem and getting the error "rtm.buildnml.csh could not find restart file for branch or hybrid start.". But I am using CESM1.2.2, and the compset is BRCP26C5CN. Even though I read the script of "rtm.buildnml.csh" and learned that RTM can use CLM restart file and have placed it in the run directory, I still get the error. Can anyone help or explain this? Thanks a lot!
 

Cliff Chen

New Member
Hi! I also encountered the same problem and getting the error "rtm.buildnml.csh could not find restart file for branch or hybrid start.". But I am using CESM1.2.2, and the compset is BRCP26C5CN. Even though I read the script of "rtm.buildnml.csh" and learned that RTM can use CLM restart file and have placed it in the run directory, I still get the error. Can anyone help or explain this? Thanks a lot!
You can get the restart files by running a startup case(you should set STOP_OPTION and STOP_N in env_run.xml), then cp them to the #CASEROOT/run where the case you build. I have succeed in CESM121,but I don't know if that is what you want.
 
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