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choose a F compset to compare with B1850


Siyu Zhao
New Member

I am a new user to CESM. I have a naive question: Is there a defined F compset to compare with B1850? My study purpose is to examine the role of ocean dynamics in tropical rainfall.

I found two defined F1850 compset:
And the long name for B1850 is:

The land model component is not exactly the same among the compsets (CLM50%SP in F1850, CLM50%BGC in F1850_BDRD, CLM50%BGC-CROP in B1850). Would this land model difference interfere with the comparison between F1850(_BDRD) and B1850 simulations to differentiate oceanic effects?

Any help would be really appreciated.


I will answer about the land model:
Yes, comparing SP versus BGC versus CROP will not give you a clean comparison. For a clean comparison, you should pick one.

I have not used the following capability in a while to tell you exactly how it's done:
If you do not find what you want in the "short-hand" compsets, you can make your own compsets by modifying the long names.


Siyu Zhao
New Member
Thank you for your answer!

I added a F compset <alias> and <lname> to a script that is originally located in $SRCROOT/components/cam/cime_config/config_compsets.xml. The model was able to run. Does this seem right?


Bill Sacks
CSEG and Liaisons
Staff member
@zhaos - yes, that approach is a good one. Another way to do it is to use the long name directly as the --compset argument to create_newcase. That method is easier so you don't need to modify an xml file, but if you have things working by modifying the xml file, then your approach is a good one.