List of experiments



The goal is to run the experiment of your choice for 14 months starting on 1st of January until 1st of March the following year. For this use the same restart file you used for the test experiment. Each of the 4 experiments is given an experiment name:
  1. EXPNAME=CO2:Quadrupling of CO2 (change CO2 value to 4x367 ppm = 1468 ppm > change the name list)
  2. EXPNAME=sea_ice: Melt of Arctic sea ice (set sea ice fraction to zero North of 30N > change the input data set)
  3. EXPNAME=SST: Super El Nino (add +8 K to tropical Central and East Pacific SST from 5S to 5N, 180W to 85W > change the input data set)
  4. EXPNAME=himalaya: Lowering of Himalaya Mountains (set surface Geopotential to 0 from 25N to 40N and 70E to 100E > change the input data set)

Make sure you define an environment variable EXPNAME, every time you login on Abel: 
# define an environment variable for your experiment (CO2, sea_ice, SST, himalaya)
export EXPNAME=CO2

Here is the list of tasks to perform for the experiment of your choice:
  1. Create a new case for your experiment
  2. Setup experiment duration (5 days)
  3. Experiment namelist or dataset change

Create a new case for your experiment


Use an appropriate name for your new experiment depending on your experiment (tripling CO2, Sea ice, etc.). Suggested EXPNAME are given above.
Create a new case always involve executing create_newcase.

On Abel: 
cd $HOME/cesm/cesm1_2_2/scripts

# Adjust EXPNAME depending on your experiment (CO2, sea_ice, SST, himalaya)

export EXPNAME=CO2
#
# Simulation 2: Long simulation
#
./create_newcase -case ~/cesm_case/f2000.T31T31.$EXPNAME -res T31_T31 -compset F_2000_CAM5 -mach abel


Now you should have a new directory in $HOME/cesm_case/f2000.T31T31.$EXPNAME corresponding to your new case.
On Abel: 

# Make sure EXPNAME is correctly defined!

cd ~/cesm_case/f2000.T31T31.$EXPNAME

As before we start from the control experiment:
On Abel: 
./xmlchange RUN_TYPE=hybrid
./xmlchange RUN_REFCASE=f2000.T31T31.control
./xmlchange RUN_REFDATE=0009-01-01

Setup your new experiment duration


Before running the long simulation (14 months), you would like to check your new settings on a short experiment. You will first run 5 days; check the results and then restart the same experiment for 14 months.
Make sure you set the duration of your experiment properly. Here we wish to run 5 days from the control experiment: 
./xmlchange -file env_run.xml -id STOP_N -val 5
./xmlchange -file env_run.xml -id STOP_OPTION -val ndays

Now we are ready to set-up the model configuration and build the cesm executable.

On Abel: 
./cesm_setup

# Make sure EXPNAME is set properly!

./f2000.T31T31.$EXPNAME.build


The default history file from CAM is a monthly average. We can change the output frequency with the namelist variable nhtfrq For instance to change the history file from monthly average to daily average, we set the namelist variable nhtfrq = -24. We also need to copy restart files in your running directory, etc.:

On Abel: 
cat >> user_nl_cam << EOF
nhtfrq = 0,-24
fincl2 = 'T', 'U', 'V', 'PS', 'OMEGA'
EOF
cat >> user_nl_cice << EOF
grid_file = '/work/users/$USER/inputdata/share/domains/domain.ocn.48x96_gx3v7_100114.nc'
kmt_file = '/work/users/$USER/inputdata/share/domains/domain.ocn.48x96_gx3v7_100114.nc'
EOF

# Make sure EXPNAME is set properly!      

scp login3.norstore.uio.no:/projects/NS1000K/GEF4530/outputs/runs/f2000.T31T31.control/run/f2000.T31T31.control.*.0009-01-01-00000.nc  /work/users/$USER/f2000.T31T31.$EXPNAME/run/.
scp login3.norstore.uio.no:/projects/NS1000K/GEF4530/outputs/runs/f2000.T31T31.control/run/rpointer.* /work/users/$USER/f2000.T31T31.$EXPNAME/run/.


Now depending on your experiment case, you would have either to change the namelist or to change the input dataset.

Experiment namelist or dataset change