Setup for a hybrid run

[nick_szapiro@ou_edu]

Hi,
I'm trying to set up a non "out-of-the-box" case, and I'm afraid I'm a bit lost.
For concreteness, say I have restart files for CLM+POP+CICE from the CESM Large Ensemble for 2006-01-01 (end of B20TRC5CN run). I'm using MPAS as the CAM dynamical core with separate initial conditions (and mapping files to the land and ocean grids, dry deposition file,...). The following is as far as I've gotten for configuring this case:

1) create_newcase -case mpas.B20TRC5CN.t01 -compset B20TRC5CN -res mp120km -mach yellowstone -compiler intel -pes_file sample_pes_file.xml

2) In user_nl_cam:
ncdata='path to mpas-a IC file'
drydep_srf_file = 'path to mpas-a drydep file'

3) In user_nl_cice:
ice_ic = 'path to cice restart'

4) In user_nl_clm
finidat = 'path to clm restart'
Change fsurfdat to a different dataset?

5) Do nothing for cpl

6) POP2: I'm not sure what variables to set

7) In user_nl_rtm
finidat_rtm = 'path to rtm restart'
Change frivinp_rtm to match fsurfdat in clm?

This is all in version 1.2.2.
Any help is greatly appreciated.
Thanks in advance!
Nick

 

[nick_szapiro@ou_edu]

Is it necessary to use the "startup" setting for the spun-up ocean (http://www.cesm.ucar.edu/models/cesm1.2/cesm/doc/usersguide/x2370.html)?
I think this setup is a "hybrid" run, no?

 

[santos]

I think that, unless there is some specific reason why you need to re-initialize POP, you should use a hybrid run. In this situation, you do not need to specify the restart/initial files for components other than CAM (CAM itself will use your specified ncdata and ignore any restart files for a hybrid run). Instead, what you want to do is to set RUN_REFCASE and RUN_REFDATE in env_run.xml, to give the name of the case you want to start from and the year that you're using from that case.Note that the restart files by themselves are not enough. You also need the rpointer files that were generated by the run. I also believe that POP has multiple files read during restarts, so you will need all of those.As for changing mapping and drydep files for MPAS, if you need any help with that, someone else will have to answer, since I'm not really familiar with what we do for new dycores/grids. If you have any MPAS-specific questions, you'll have to ask whoever gave you the code modifications to run MPAS; using MPAS as the CAM dycore is not a feature that's part of CESM right now, so I expect that few-to-none of us have any experience with it.Edit: It's probably obvious from context, but I meant RUN_REFDATE, not RUN_STARTDATE.

 

[nick_szapiro@ou_edu]

Thank you so much for your reply! Everything makes much more sense...the non-MPAS setup is good now.