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arXiv · 1408.4366

Localized vorticity enhancement through superhelical coherent structure in observed tornadic supercells

Marcus Büker·Luke Odell·Joshua Wurman·Karen Kosiba·James Marquis
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Abstract

New diagnostic methods are presented for localized, barotropic vorticity evolution in tornadic environments. These methods focus on superhelicity, a quantity shown to be strongly related to local maxima in vorticity tendency. Mobile Doppler radar retrievals from three well-known cases of tornadogenesis were studied with this new approach. The results show promise for detecting and tracking coherent dynamical features known to be related to tornadogenesis, as well as detecting signals of imminent tornadogenesis at an earlier stage than vorticity tendency analysis. Furthermore, these methods may provide physical insight into vortex-vortex interactions and vortex modes in the vicinity of the mesocyclone.

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Marcus Büker, Luke Odell, Joshua Wurman, Karen Kosiba, James Marquis. 2014-08-19. Localized vorticity enhancement through superhelical coherent structure in observed tornadic supercells. https://arxiv.org/abs/1408.4366

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