HW Linear Baroclinic Model¶

Individual Work¶

Credits: 15%¶

Grading:¶

Yu-Chiao Liang (15%)

Deadline: xxx¶

The Tasks¶

Set up and run the model successfully.
Learn how to change forcing strength, shape, and location.
Reproduce the results with Central Pacific warming.
Check:
- Background fields and forcings.
- Winds, sea-level pressure, geopotential height, temperature fields.
Use diagnostic tools to analyze the wave activity features.
Group work will be to modify Arctic forcing. For example, you can move the tropical forcing to Arctic region.

The Model¶

This linear baroclinic model (LBM) was developed and maintained by Dr Michiya Hayashi. The official website is here. I have ported LBM on workstation xxx. Please ask your group leaders for login information.

Running the Model¶

Copy folder LBM_standard to your own directory.
export LNHOME=’/home/xxx/LBM_xxx/ln_solver’
Edit Lmake.inc file
Compile model:
- cd $LNHOME/model/src
- make clean
- make lib
- You should find a file called liblbm2t21ml11c.a under $LNHOME/model/lib/linux/
Builde model:
- cd $LNHOME/model/src
- make clean.special
- make lbm
- You should find a file called lbm2.t21ml11ctintgr under $LNHOME/model/bin/linux
Prepare forcing:
- cd $LNHOME/solver/util
- Edit SETPAR
- make clean
- make
- ./mkfrcng
- cd $LNHOME/sample/
- You should see the forcing file you created.
- Use Grads to check forcing (e.g., (1) edit xxx.ctl, (2) type grads, (3) open xxx.ctl, (4) d t)
Run model:
- cd $LNHOME/model/sh/tintgr
- Edit xxx.csh (e.g., linear-run.t21l5.test.csh)
- ./xxx.csh
- Monitor output log file under $LNHOME/data/out
Postprocess and visualize results
- cd $LNHOME/solver/util
- Edit SETPAR
- ./gt2gr
- Convert grd file to nc file: cdo -f nc import_binary xxx.ctl output_temp.nc

CTL File Example¶

* sample file fot products of a linear integration
DSET ^linear.test.grd
OPTIONS SEQUENTIAL YREV BIG_ENDIAN
TITLE time-integration
UNDEF -999.
XDEF 64 LINEAR 0. 5.625
YDEF 32 LEVELS -85.761 -80.269 -74.745 -69.213 -63.679 -58.143 -52.607
-47.070 -41.532 -35.995 -30.458 -24.920 -19.382 -13.844 -8.3067 -2.7689
2.7689 8.3067 13.844 19.382 24.920 30.458 35.995 41.532 47.070 52.607
58.143 63.679 69.213 74.745 80.269 85.761
ZDEF 11  LEVELS 1000 950 900 850 700 500 300 200 100 30 10
TDEF 60 LINEAR 01jan0000 1dy
VARS 8
psi    11 99 stream function     [m**2/s]
chi    11 99 velocity potential  [m**2/s]
u      11 99 zonal wind          [m/s]
v      11 99 meridional wind     [m/s]
w      11 99 p-vertical velocity [hPa/s]
t      11 99 temperature         [K]
z      11 99 geopotential height [m]
p       1 99 surface pressure    [hPa]
ENDVARS

Tropical Forcing Example¶

Diagnostic Tools¶

Eliassen-Palm (EP) flux
- NCL function
- Python function
Wave Activity Fluxes
- GrADS
- Python
Rossby Wave Source
- Python
Streamfunction and Velocity Potential
- Python

Polar Climate Change