vorticity

vortex +‎ -ity

vorticity (countable and uncountable, plural vorticities)

1. (mathematics, fluid dynamics) A property of a fluid flow related to local angular rotation; defined as the curl of the flow's velocity field.
   • 2004, Zhu Xun, ‎Li Xiaofan, & ‎Cai Ming, Observation, Theory And Modeling Of Atmospheric Variability, →ISBN, page 13:

     It might sound puzzling that the ageostrophic geopotential (or the ageostrophic pressure in z-coordinate) has no impact on the evolution of the vorticity of a quasi-geostrophic disturbance and yet it affects the perturbation kinetic energetics (not globally but locally).

   • 2009 February 20, William M. Durham et al., “Disruption of Vertical Motility by Shear Triggers Formation of Thin Phytoplankton Layers”, in Science‎, volume 323, number 5917, DOI:10.1126/science.1167334, pages 1067-1070:

     This results from the vorticity component of shear, whereas elongated cells would further be affected by the rate of strain component.

   • 2013 March 1, Frank Fish, George Lauder, “Not Just Going with the Flow”, in American Scientist‎, volume 101, number 2, page 114:

     An extreme version of vorticity is a vortex. The vortex is a spinning, cyclonic mass of fluid, which can be observed in the rotation of water going down a drain, as well as in smoke rings, tornados and hurricanes.