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CLIMATE/EARTH 401�Geophysical Fluid Dynamics�Dynamical Meteorology

Richard B. Rood

rbrood@umich.edu

https://clasp.engin.umich.edu/people/richard-b-rood/

https://openclimate.org/

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Vorticity 5: Tilting Term

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Vorticity and Divergence

  • Related to shear �of the velocity field.

∂v/∂x-∂u/∂y

  • Related to stretching �of the velocity field.

∂u/∂x+∂v/∂y

​

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Let’s go through this term by term

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Tilting term

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Remember the definition of relative vorticity

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Tilting Term

Tilting:

  • Change in vertical component of vorticity by tilting horizontal vorticity into the vertical

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Tilting Term

y

x

z

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Tilting Term

y

x

z

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Tilting Term

y

x

z

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Tilting Term

rotation in, say, (y, z) plane, “vorticity” in x plane

as the wheel is turned there is a component of “vorticity” in the z plane

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End: Vorticity 5: Tilting Term

Richard B. Rood

rbrood@umich.edu

https://clasp.engin.umich.edu/people/richard-b-rood/

https://openclimate.org/