| 1 | ------- |
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| 2 | purpose |
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| 3 | ------- |
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| 4 | This demonstration case allows for examining the sea ice rheology under idealised |
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| 5 | forcing. The set-up follows the paper "Stress and deformation characteristics of sea |
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| 6 | ice in a high-resolution, anisotropic sea ice model" by Heorton et al, Phil. Trans, |
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| 7 | R. Soc. 2018. |
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| 8 | |
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| 9 | ----------- |
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| 10 | Experiments |
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| 11 | ----------- |
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| 12 | A range of experiments can be configured: |
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| 13 | |
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| 14 | - The suggested experiment is to examine the different shear patterns formed |
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| 15 | by different rheologies. The default set-up reproduces the leftmost panels |
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| 16 | of figure 3a (ln_rhg_EAP true in namelist_ice_cfg) and 3b (ln_rhg_EVP true in |
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| 17 | namelist_ice_cfg). Increase the last time step in namelist_cfg appropriately |
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| 18 | to generate the other panels. |
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| 19 | |
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| 20 | - The resolution of the box can be changed analogous to figure 2 of the paper |
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| 21 | (change rn_dx and rn_dy in namelist_cfg, default is 2000m) |
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| 22 | |
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| 23 | - The ratio of the windstress component can be changed to cause different modes |
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| 24 | of failure (Rwind in usrdef_sbc.F90, default is -0.8) |
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| 25 | |
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| 26 | It takes about 10 minutes to run a simulation on 16 processors |
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| 27 | |
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| 28 | ---------- |
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| 29 | How to run |
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| 30 | ---------- |
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| 31 | |
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| 32 | a) Compile and run the model once to get mesh_mask_xxxx.nc files. |
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| 33 | E.g., starting in the root NEMO directory: |
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| 34 | |
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| 35 | ./makenemo -a ICE_RHEO -r ICE_RHEO_TEST -m X64_MOBILIS -j 4 |
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| 36 | cd tests/ICE_RHEO_TEST/EXP00 |
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| 37 | mpirun -np 1 ./nemo |
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| 38 | |
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| 39 | c) Create the initial condition file for sea-ice (initice.nc) by running |
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| 40 | this python script: |
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| 41 | |
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| 42 | python ../../ICE_RHEO/EXPREF/make_INITICE.py |
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| 43 | |
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| 44 | d) Run the model a second time |
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| 45 | |
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| 46 | mpirun -np 16 ./nemo |
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| 47 | |
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| 48 | --------------- |
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| 49 | What to look at |
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| 50 | --------------- |
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| 51 | EVP rheology has less defined shear strain maxima (linear kinematic |
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| 52 | features). If the model is run longer one can see that the LKFs appearing |
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| 53 | with EVP rheology intersect at a different angle than with EAP rheology |
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| 54 | |
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