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adele-morrison / easterlies-collaborative-project

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Wind stress change #15

Closed adele-morrison closed 3 years ago

adele-morrison commented 3 years ago

Plot maps and zonal averages of the tau_x and tau_y stress on the ocean.

julia-neme commented 3 years ago

Notebook: https://github.com/adele157/easterlies-collaborative-project/blob/master/notebooks/Wind-stress-change.ipynb

These are using tau_x and tau_y which are not strictly wind stresses, but total relative stress if I remember correctly? So ice+wind relative stresses. Should I do this for the JRA forcing files?

tau_xy-ryf-mean (2)

tau_xy-easup-mean (2)

tau_xy-easdown-mean (2)

Zonal averages:

zonalwind

adele-morrison commented 3 years ago

Nice! Yes, I think it would be nice to do these for the JRA forcing files also (there's another issue for that here where Matt suggested vector plots actually). That way we have some idea of the expected impact of the winds on sea ice also.

StephenGriffies commented 3 years ago

Very nice images.

It would indeed be nice to see what is pure wind stress and what is under-ice stresses. Perhaps one only needs to apply an ice mask.

Also, small comment: it would be useful to colour the land light gray to help distinguish land from ocean. As there is white currently in the ocean colormap, it can be tough in some places to know what is land and what is ocean.

julia-neme commented 3 years ago

I think that the model calculates relative stresses, weighted by sea ice concentration. So, tau is:

tau = \alpha \tau_{ice\ocean} + (1-\alpha) \tau_{air/ocean}

The figures below are purely wind stress (calculated from the forcing files), but unlike tau_x and tau_y this is total stress. I think that in spite of this, in the zonal averages you can see how sea ice dampens the stress (wind + ice < wind). Spatial patterns seem very much alike..

tau_xy_wind-ryf-mean tau_xy_wind-easup-mean tau_xy_wind-easdown-mean image871