Scheduled Downtime
On Tuesday 24 October 2023 @ 5pm MT the forums will be in read only mode in preparation for the downtime. On Wednesday 25 October 2023 @ 5am MT, this website will be down for maintenance and expected to return online later in the morning.
Normal Operations
The forums are back online with normal operations. If you notice any issues or errors related to the forums, please reach out to help@ucar.edu

FAQ: Data ocean slab mode (DOCN-SOM)

E

edu061

Etienne Dunn-Sigouin
New Member
Hi Dave,

I'd like to run a F1850C5 compset with SST/ICEFRAC boundary conditions derived from the climatology of a E1850C5CN compset run. I am running CESM 1.1.2. My questions are:

1) Is there an example boundary condition file available in the online repository I can look at to help me create my own?
2) Do I need to do the 'diddling' procedure using 'icesst tools' mentioned in other threads (e.g. here)? Or is this just for using observations as boundary conditions?
3) How do I point the model to the boundary condition file I created?
4) What type of run should I do, start-up, branch or hybrid ? The simulation will go from slab-ocean to fixed sst so not sure what is recommended here.
5) Is there a way to make an F1850C5CN type compset by running F1850C5 and adding a flag for 'CN' ?
6) Is it possible to do a similar F compset using boundary conditions derived from the climatology of a QSC5 compset run? (Here i'd be using another version of the model cesm 2.1.0)

Thanks for your help,
Etienne
 
R

Riley

hanzy
New Member
Hello Dave,
I have a question. Would the global mean Qflux in the default SOM file (e.g. pop_frc.b.e11.B1850C5CN.f09_g16.005.150217.nc) be zero or a fixed value XXX W/m2? I would like to create my own SOM forcing file calculated from a fully coupled simulation similar to the pre-industrial run. Is the new Qflux equal to the default Qflux globally?

When I run the model with my own SOM forcing file, it caused an error after running 40 years:
Starting thermo, Tsn < Tmin
Tsn= -100.003310145348
Tmin= -100.000000000000
istep1, my_task, i, j: 378046 6 13 5
qsn -179993222.795575
istep1, my_task, iblk = 378046 6 1
Global block: 79
Global i and j: 300 52
Lat, Lon: -76.7792188253289 -60.0624999999955
(shr_sys_abort) ERROR: ice: Vertical thermo error
(shr_sys_abort) WARNING: calling shr_mpi_abort() and stopping

Most places are covered in ice. Thus, it seems that the SOM forcing file calculated from a fully coupled simulation is not conserved?
 
D

dbailey

CSEG and Liaisons
Staff member
The key part of this is that the surface temperature is dropping below -100C. This likely starts sooner in the run. Check your atmospheric state to make sure it is not going off the rails. Sounds like you may have missing values in your SOM file. Values of zero would be ok, but you also need to check the TOA imbalance in the atmosphere.
 
R

Riley

hanzy
New Member
Hello Dave,
Thanks a lot, there are some missing values in my modified forcing file. I had set the missing values to zero. But I have another trouble.

I found that the model became progressively colder and colder after ~20-30 years, when the TOA imbalance in the atmosphere began (net longwave flux is bigger than net shortwave flux). 40 years later or 70 years later, the global surface temperature will below 10 degrees.
I check the net flux of atmospheric ((FLNT-FSNT) -(FLNS-FSNS) -(LHFLX+SHFLX)), it keeps the positive imbalance.
It looks like the atmosphere is losing energy gradually.

The trouble exists whether the default SOM file (e.g. pop_frc.b.e11.B1850C5CN.f09_g16.005.150217.nc) or my modified forcing file is used.
It seems that the SOM forcing file is not balanced state?

Thanks,
Riley.
 
D

dbailey

CSEG and Liaisons
Staff member
How big is the TOA imbalance? This might explain the cooling. Ideally the SOM forcing should not be removing heat globally.

Dave
 
K

KumarSumit

Sumit Kumar
New Member
mpb20@st-andrews_ac_uk said:
Hi there,

I've recently been running cesm2.1.3 at resolution f19_g16 with the following compset: 1850_CAM40_CLM40%CN_CICE_DOCN%SOM_RTM_SGLC_SWAV

The slab-ocean forcing file is: pop_frc.b.c40.B1850CN.f19_g16.100105.nc

What I find is that the model becomes progressively colder and colder before crashing after approximately 35 years. This behaviour is surprising, and I'm wondering whether anyone else has seen this using cesm2 and a similar compset?

Cheers,

Mike
Click to expand...
Yes, Mike
I am getting the same error with the same compset.
Have you fixed that now?
can you suggest me something?
Thanks.
Sumit.
 
O

ohmpawat

ohmpawat chen
Member
edu061 said:
Hi Dave,

I'd like to run a F1850C5 compset with SST/ICEFRAC boundary conditions derived from the climatology of a E1850C5CN compset run. I am running CESM 1.1.2. My questions are:

1) Is there an example boundary condition file available in the online repository I can look at to help me create my own?
2) Do I need to do the 'diddling' procedure using 'icesst tools' mentioned in other threads (e.g. here)? Or is this just for using observations as boundary conditions?
3) How do I point the model to the boundary condition file I created?
4) What type of run should I do, start-up, branch or hybrid ? The simulation will go from slab-ocean to fixed sst so not sure what is recommended here.
5) Is there a way to make an F1850C5CN type compset by running F1850C5 and adding a flag for 'CN' ?
6) Is it possible to do a similar F compset using boundary conditions derived from the climatology of a QSC5 compset run? (Here i'd be using another version of the model cesm 2.1.0)

Thanks for your help,
Etienne
Click to expand...
Hi, Etienne,

I'd also curious about these questions. Have you solved?


Best,
ohmpawat
 
M

m_dvorak

Michelle
New Member
Hello Dave,

I'm having difficulty accessing the file that describes how to create a Qflx and mixed layer depth data file for a SOM simulation. My cheyenne account credentials do not grant me access; how might I view this document?

I am looking to create a CESM1.2 piControl SOM file. Unless I am mistaken, the list of available files does not include CESM1.2. Is this correct?

Thank you,

Michelle
 
D

dbailey

CSEG and Liaisons
Staff member
There is a special guest account for the svn repository. You can get the "super secret" userid and password by registering here:

CESM | User Registration

www.cesm.ucar.edu www.cesm.ucar.edu

We do have some from CESM1.0, 1.1, 1.3 and 1.5. There is a string like e11 in the filename which is the version of CESM it came from. The 1.1 files would be fine with CESM1.2. The CESM1 large ensemble (including SOM runs) was done with CESM1.1.
 
M

m_dvorak

Michelle
New Member
dbailey said:
There is a special guest account for the svn repository. You can get the "super secret" userid and password by registering here:

CESM | User Registration

www.cesm.ucar.edu www.cesm.ucar.edu

We do have some from CESM1.0, 1.1, 1.3 and 1.5. There is a string like e11 in the filename which is the version of CESM it came from. The 1.1 files would be fine with CESM1.2. The CESM1 large ensemble (including SOM runs) was done with CESM1.1.
Click to expand...

Thank you!
 
M

m_dvorak

Michelle
New Member
Hello again,

I am having an issue with CESM1.2 reading my modified user_docn.streams.txt.som file at build time, which I copied from CaseDocs, edited to point toward the path of my own DOCN_SOM file, and placed in the $CASEROOT/ directory as instructed. The issue occurs when I attempt to build the model, where it seems to stall while reading/writing the DOCN namelists. This is where the model gets to before it does not do anything anymore (no error messages are thrown):

CESM BUILDNML SCRIPT STARTING
- To prestage restarts, untar a restart.tar file into /glade/scratch/mtdvorak/e.e12.E1850C5.f09_fg16.piControl/run
infile is /glade/u/home/mtdvorak/cases/SOM/e.e12.E1850C5.f09_fg16.piControl/Buildconf/cplconf/cesm_namelist
CAM writing dry deposition namelist to drv_flds_in
CAM writing namelist to atm_in
CLM configure done.
CLM adding use_case 1850_control defaults for var sim_year with val 1850
CLM adding use_case 1850_control defaults for var sim_year_range with val constant
CLM adding use_case 1850_control defaults for var use_case_desc with val Conditions to simulate 1850 land-use
CICE configure done.

At this point I have to terminate the script.

I moved a preexisting DOCN file from the /ocn/docn7/SOM directory to my own directory to see if the problem was with my particular file, but the same problem occurs. Does anyone have experience with this issue?

Thank you,

Michelle
 
D

dbailey

CSEG and Liaisons
Staff member
Looks like the path to your SOM file is not complete:

/glade/work/mtdvorak//pop_frc.b.e12.B1850C5CN.f09_g16.preind.751-800.nc

I assume the case directory is missing?
 
M

m_dvorak

Michelle
New Member
Thank you -- you are correct, I was missing the /SOM/ directory in that path for DOCN_SOM_FILENAME. But, the file paths in the docn.streams.txt.som file are correct, and the problem seems to arise regardless of env_run.xml settings. I believe it's a namelist issue.
 
D

dbailey

CSEG and Liaisons
Staff member
You don't seem to have any log files for your build. Is there nothing from DOCN that says where the build is having troubles? Also, try a clean build:

./e.e12.E1850C5.f09_fg16.piControl.clean_build

Also, while I don't think it is and issue, the case name has a resolution combination of f09_fg16 ... I think this should be f09_g16.
 
M

m_dvorak

Michelle
New Member
It seems that it can't complete ./preview_namelists. I don't see any build logs because I don't think it has actually gotten to the build phase. I think the issue is with the user_docn.streams.txt.som file and the customized pathway. When I create a case with a DOCN file that lives in the default /docn7/SOM directory, I have no issues.
 
D

dbailey

CSEG and Liaisons
Staff member
You can move it there, but just know that everyone can access it there. What is the error message from preview_namelist?

Dave
 
M

m_dvorak

Michelle
New Member
I am not getting any error messages from preview_namelist, or $CASE.build. They just does not complete the task (stalls out at 'CICE configure done.'). I don't get an error when I interrupt it either.

I don't seem to have permission to move a file into the docn7/SOM directory.
 
D

dbailey

CSEG and Liaisons
Staff member
Ok. I just copied it there for you. Let me know if that works. What if you just run:

./preview_namelists

Dave
 
You must log in or register to reply here.
Top