1: Control case#

NOTE: Building the control case for the CICE challenge exercises is idential to building the control case in the POP challenge exercises. If you have already completed the POP challenge exercises you can skip this step.

Exercise: Run a control case

Create a case called g_control using the compset G at T62_g37 resolution.

Set the run length to 1 year.

Build and run the model. Since this is a control case, we want to build it “out of the box” without any modifications.

Click here for hints

How do I compile?

You can compile with the command:

qcmd -- ./case.build

How do I control the output?

Use namelist variables: histfreq, histfreq_n, and f_var.

histfreq = 'm','d','x','x','x'
histfreq_n = 1,1,1,1,1

f_aice = 'mdxxx'
f_hi = 'mdxxx'

CICE History

How do I check my solution?

When your run is completed, go to the archive directory.

(1) Check that your archive directory contains the files:

  • h files

g_control.cice.h.0001-01.nc

  • h1 files

g_control.cice.h1.0001-01-01.nc
g_control.cice.h1.0001-01-02.nc

(2) Compare the contents of the h and h1 files using ncdump.

ncdump -h g_control.cice.h.0001-01.nc
ncdump -h g_control.cice.h1.0001-01-01.nc

Look at the sizes of the files.

ls -l g_control.cice.h.0001-01.nc
ls -l g_control.cice.h1.0001*.nc
Click here for the solution

Create a new case g_control with the command:

cd /glade/work/$USER/code/my_cesm_code/cime/scripts/
./create_newcase --case /glade/work/$USER/cases/g_control  --compset G --res T62_g37

Case setup:

cd ~/cases/g_control 
./case.setup

Change the run length:

./xmlchange STOP_N=1,STOP_OPTION=nyears

If needed, change job queue and account number. For instance:

./xmlchange JOB_QUEUE=regular,PROJECT=UESM0011

Build and submit:

qcmd -- ./case.build
./case.submit

When the run is completed, look into the archive directory for: g_control.

(1) Check that your archive directory on cheyenne (The path will be different on other machines):

cd /glade/scratch/$USER/archive/g_control/ice/hist

ls

(2) Compare the contents of the h and h1 files using ncdump.

(3) Check the number of timesteps / files for the h and the h1 files.

  • h1 has 31 time samples / files.

  • Check the size of the files

du –ks –h /glade/scratch/$USER/archive/g_control/ice/hist/*